Java in Hindi Updated

Java in Hindi BccFalna.com 097994-55505

Kuldeep Chand

This EBook is not Just Core Java, but also includes some concepts of Advance Java like Basics of JDBC, Event Driven Programming, GUI development with AWT and Basics of Java Networking too. In Java, all GUI development like SWT/Swing, JavaFX etc… are totally based on AWT. So, learning AWT helps very much in learning GUI Development using Java. So, in this EBook, I have covered GUI Development from and covered AWT and Event Driven Programming with Good Detail in Last Chapter. So that, after reading this EBook, you can start developing GUI Applications using Java easily. Even Applets are out of market now, but I have included it frequently in this EBook to easily using and understanding GUI Development. Basics. I have covered each Java Programming Concept with hundreds of example programs. So, it would be very easy to learn Java with this EBook.

Java in Hindi

Kuldeep Chand BetaLab Computer Center Falna

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Java in Hindi Programming Language JAVA in Hindi Copyright © 2011 by Kuldeep Chand All rights reserved. No part of this work may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopying, recording, or by any information storage or retrieval system, without the prior written permission of the copyright owner and the publisher. Trademarked names may appear in this book. Rather than use a trademark symbol with every occurrence of a trademarked name, we use the names only in an editorial fashion and to the benefit of the trademark owner, with no intention of infringement of the trademark. Lead Editors: Kuldeep Chand Distributed to the book trade worldwide by Betalab Computer Center, Behind of Vidhya Jyoti School, Falna Station Dist. Pali (Raj.) Pin 306116 e-mail [email protected] or visit http://www.bccfalna.com For information on translations, please contact Betalab Computer Center, Behind of Vidhya Jyoti School, Falna Station Dist. Pali (Raj.) Pin 306116 Phone 97994-55505 The information in this book is distributed on an “as is” basis, without warranty. Although every precaution has been taken in the preparation of this work, the author shall not have any liability to any person or entity with respect to any loss or damage caused or alleged to be caused directly or indirectly by the information contained in this book.


Java in Hindi

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Java in Hindi

Index of Contents


Java in Hindi Table of Contents Java – Basics and Programming Fundamentals ....................................................... 13 Features of JAVA .................................................................................................. 17 Small and Simple ............................................................................................... 17 Object Oriented .................................................................................................. 17 Distributed .......................................................................................................... 18 Compiled and Interpreted .................................................................................. 18 Robust and Safe ................................................................................................ 19 Architecture Neutral / Platform Independent / Portable / Byte Coded ................ 19 Garbage Collective ............................................................................................ 20 High Performance .............................................................................................. 20 Multithreaded and Interactive ............................................................................. 20 Dynamic and Extensible .................................................................................... 20 Java – Working ...................................................................................................... 22 Java Platform ......................................................................................................... 23 The Essentials: .................................................................................................. 24 Applets: .............................................................................................................. 24 Networking: ........................................................................................................ 24 Internationalization: ............................................................................................ 24 Security: ............................................................................................................. 25 Software components: ....................................................................................... 25 Object serialization: ............................................................................................ 25 Java Database Connectivity (JDBC): ................................................................. 25 Program ................................................................................................................. 25 Procedural Techniques and OOPS ....................................................................... 27 The Object-Oriented Approach .............................................................................. 29 Difference Between C++ and Java ........................................................................ 31 Preprocessor ...................................................................................................... 31 Pointers .............................................................................................................. 32 Structure and Union ........................................................................................... 32 Functions ........................................................................................................... 33 Multiple Inheritance ............................................................................................ 33 Strings ................................................................................................................ 34 goto Statement ................................................................................................... 34 Operator Overloading ........................................................................................ 34 Automatic Type Casting ..................................................................................... 34 Variable Number of Arguments .......................................................................... 35 Command Line Argument .................................................................................. 35 Programming – The Basic Concept ....................................................................... 36 System Software: ............................................................................................... 37 Application Software: ......................................................................................... 37 Computer Architecture ....................................................................................... 37 Hardware Programming ..................................................................................... 39 Software Programming ...................................................................................... 40 Language ............................................................................................................... 40 Java Compiler (javac) ........................................................................................ 41 Java Interpreter (java) ........................................................................................ 42 Structure of Java Programs ................................................................................... 43 Documentation Section ...................................................................................... 43 Package Statements .......................................................................................... 43 Import Statements .............................................................................................. 44


Java in Hindi Interface Statements .......................................................................................... 44 Main Method Class ............................................................................................ 44 Definition – The Applet and Application ................................................................. 44 Java - Applications ............................................................................................. 45 First Application in Java ..................................................................................... 45 Compiling Java Source File ............................................................................... 46 Running Java Application .................................................................................. 48 Anatomy of Java Application .............................................................................. 48 Comments in Java ............................................................................................. 48 Java – Applet ......................................................................................................... 51 Applet – Local and Remote ................................................................................ 51 Clients and Servers ............................................................................................ 52 Difference – Applet and Application ...................................................................... 53 Preparation – The Applet Writing ....................................................................... 53 System Package – Predefined (Built-In) Library of Java Classes ...................... 54 Using – The System Packages ......................................................................... 55 Keyword / Reserve Word ................................................................................... 56 Building – The Applet Code ............................................................................... 57 Applet Package – The Applet Class .................................................................. 57 OOPS and OOPL – The Definition ........................................................................ 58 Problem – The Definition ....................................................................................... 58 Data – Value OR a Set of Values .......................................................................... 59 Integer ................................................................................................................ 59 Float ................................................................................................................... 59 Character ........................................................................................................... 59 Object – The Definition .......................................................................................... 59 Objects – Based on Problem ................................................................................. 60 Abstraction – The Problem Simplifying Process .................................................... 60 Abstract Data Type - Logical Representation of a Real World Object ................... 61 Attributes – The Data Members of The Class .................................................... 62 Behaviors – The Methods of The Class ............................................................. 62 Problem Design (OOPS) v/s Problem Implementation (OOPL) ............................ 63 Encapsulation – The Unitizing Process of Attributes and Behaviors ..................... 64 Class – A Logical Specification of Problem Related Object .................................. 65 Identifier Naming System ...................................................................................... 70 Java – Graphical User Interface and Graphics Management ................................ 72 Web Page – The Part of Website .......................................................................... 72 HTML Tags for Web Pages ................................................................................... 74 Comment Section .............................................................................................. 74 Head Section ..................................................................................................... 75 Body Section ...................................................................................................... 75 Adding Applet in HTML File ................................................................................... 75 Applet Architecture – The Event Based GUI Application Program ........................ 76 First Applet in Java ................................................................................................ 82 GUI – The Event Driven Programming System ................................................. 84 Components of an Event ....................................................................................... 86 Event Object ...................................................................................................... 86 Event Source ..................................................................................................... 87 Event Handler .................................................................................................... 87 Java Fundamentals – Core Concepts ....................................................................... 91 Constants .............................................................................................................. 91 Variables ................................................................................................................ 93


Java in Hindi Naming Constants and Variables – The Identifiers ............................................... 93 “Java” Characterset ............................................................................................... 95 “Java” Tokens ........................................................................................................ 95 Keywords ;k Reserve Words .............................................................................. 96 Identifiers ........................................................................................................... 96 Literal ................................................................................................................. 97 Variables ............................................................................................................ 99 Operators ......................................................................................................... 100 Precedence Of Operators ................................................................................ 105 Data Types .......................................................................................................... 106 Identifier (Variable / Constant) Declaration ...................................................... 107 Value Initialization ............................................................................................ 108 Garbage Values ............................................................................................... 109 Integer Data Types .......................................................................................... 109 Floating – Point Data Types ............................................................................. 110 Boolean Data Type .......................................................................................... 111 Character Data Type ........................................................................................ 111 Variable Scope .................................................................................................... 118 Code Block .......................................................................................................... 118 Type Casting ....................................................................................................... 118 Arrays .................................................................................................................. 121 Array Memory Allocation .................................................................................. 122 Array Initialization ............................................................................................. 122 Strings ................................................................................................................. 129 String Methods ................................................................................................. 131 StringBuffer Class ............................................................................................ 136 Command Line Arguments .................................................................................. 138 Wrapper Classes ................................................................................................. 140 Control Statements .............................................................................................. 152 Program Control ............................................................................................... 153 Types Of Control Statement ............................................................................ 153 Compound Statement or Block ........................................................................ 154 Increment and Decrement ............................................................................... 164 Loops ................................................................................................................... 166 for Loop ............................................................................................................ 167 Assignment Operators ..................................................................................... 170 Nesting of Loop ................................................................................................ 171 while Loop ........................................................................................................ 176 do while Loop ................................................................................................... 178 Jump Statements ................................................................................................. 180 break Statement ............................................................................................... 180 continue Statement .......................................................................................... 182 return Statement .............................................................................................. 183 Drawing Graphics ................................................................................................ 183 Applet Canvas .................................................................................................. 183 Colors ............................................................................................................... 185 Drawing Shapes ............................................................................................... 186 Drawing Line and Rectangles .......................................................................... 186 Drawing Circles and Ellipses ........................................................................... 187 Drawing Arcs .................................................................................................... 188 Drawing Polygons ............................................................................................ 188 Building Graphical User Interface ........................................................................ 193


Java in Hindi Abstract Windowing Toolkit .............................................................................. 194 Components ..................................................................................................... 194 Panel Class – The Panel Container ................................................................. 196 Push Button Control ......................................................................................... 196 Label Control .................................................................................................... 199 Rectangles and Windows ................................................................................ 204 GUI Components – On The Absolute Placement ................................................ 204 Handling Multiple-Button Events ......................................................................... 206 Java OOPS – Object Oriented Programming Concept ........................................... 212 Class and Objects ............................................................................................... 212 Attributes .......................................................................................................... 216 Declaring Objects ............................................................................................. 224 new Operator – A Closer Look ......................................................................... 225 Object Reference ............................................................................................. 226 Abstract Data Types ........................................................................................ 238 Adding Methods to Box Class .......................................................................... 241 Methods Overloading .......................................................................................... 253 this Keyword ........................................................................................................ 254 Automatic Garbage Collection ............................................................................. 256 Finalize() Method ................................................................................................. 256 Methods Overloading .......................................................................................... 257 Constructors ........................................................................................................ 261 Arguments Passing ............................................................................................. 266 Pass By Value .................................................................................................. 266 Pass By Reference .......................................................................................... 267 Access Controls ................................................................................................... 269 public and private Access Specifier ................................................................. 270 static Data Members and Methods ...................................................................... 273 final Keyword ....................................................................................................... 276 Nested and Inner Classes ................................................................................... 276 GUI Application Of Java ...................................................................................... 278 Java Application – The Frame Class ............................................................... 279 Java Inheritance – Code Reusability ....................................................................... 285 Reusability ........................................................................................................... 285 Inheritance and Program Design ......................................................................... 286 Composition: A “Has a” Relationship ............................................................... 286 Inheritance: A “Kind of” Relationship ............................................................... 287 Superclass and Subclass .................................................................................... 289 Implementing Inheritance .................................................................................... 291 Method Overriding ............................................................................................... 299 Constructors and Inheritance .............................................................................. 302 Multilevel Hierarchy ............................................................................................. 311 Constructor Calling Convention ........................................................................... 311 Dynamic Method Dispatch – The Run Time Polymorphism ................................ 312 Abstract Classes .................................................................................................. 317 Final Classes ....................................................................................................... 322 Java Interfaces – Multiple Inheritances ................................................................... 326 Declaring Interfaces ............................................................................................. 327 Extending Interfaces ............................................................................................ 328 Implementing Interfaces ...................................................................................... 330 Java Exception – Error Handling ............................................................................. 336 Compile Time Errors ............................................................................................ 336


Java in Hindi Run Time Errors .................................................................................................. 337 Exceptions ........................................................................................................... 338 Exception Types .............................................................................................. 341 try and catch Block – The Exception Handling Process .................................. 341 Multiple catch Blocks ....................................................................................... 343 Nested try Statement ....................................................................................... 347 The throw Keyword .......................................................................................... 347 The throws Keyword ........................................................................................ 349 The finally Code Block ..................................................................................... 349 Types of Exceptions – The Java Built – In Exceptions Classes .......................... 352 java.lang Exceptions ........................................................................................ 352 java.io Exceptions ............................................................................................ 354 java.net Exceptions .......................................................................................... 354 The java.awt Exceptions .................................................................................. 354 The java.util Exceptions ................................................................................... 355 Creating Own Exception Sub Class .................................................................... 355 Java Package – Code Reusability .......................................................................... 358 Naming Conventions ........................................................................................... 359 Creating Packages .............................................................................................. 360 Java Multithreaded Programming ........................................................................... 369 Java Thread Model .............................................................................................. 370 Thread Priorities .................................................................................................. 371 The Thread Class and the Runnable Interface .................................................... 371 The Main Thread ................................................................................................. 371 Two Kinds of Threads .......................................................................................... 374 Converting a Class to a Thread ....................................................................... 374 Deriving a Class From Thread ......................................................................... 389 Thread Exception ................................................................................................ 393 Thread Scheduling – Setting Thread Priority ....................................................... 394 Establishing Thread Priority ............................................................................. 395 Daemons ............................................................................................................. 399 The ThreadGroup ................................................................................................ 400 Thread States – The Life Cycle of a Thread ........................................................ 402 NEWBORN State ............................................................................................. 403 RUNNABLE State ............................................................................................ 403 RUNNIG State ................................................................................................. 404 BLOCKED State .............................................................................................. 405 DEAD State ...................................................................................................... 405 Synchronization ................................................................................................... 407 Deadlock .............................................................................................................. 408 Java Networking ...................................................................................................... 410 World Wide Web (WWW) Concepts .................................................................... 410 Distributed Programs ........................................................................................... 410 Protocol ............................................................................................................... 411 IP Address ....................................................................................................... 411 Host .................................................................................................................. 412 Hostname ......................................................................................................... 412 IETF (Internet Engineering Task Force) .......................................................... 413 Internet ............................................................................................................. 413 Intranet ............................................................................................................. 413 Packet .............................................................................................................. 413 Protocol ............................................................................................................ 413


Java in Hindi Protocol Stack .................................................................................................. 414 Router .............................................................................................................. 414 Sockets ............................................................................................................ 414 Internet Protocols ................................................................................................ 414 TCP/IP Network Architecture ........................................................................... 414 IPv4 And IPv6 .................................................................................................. 416 URL Class ........................................................................................................... 417 Socket Class ........................................................................................................ 417 Reliable ............................................................................................................ 417 Ordered Stream ............................................................................................... 418 ServerSocket Class ......................................................................................... 418 DatagramSocket Class ........................................................................................ 418 Unreliable ......................................................................................................... 418 Connectionless ................................................................................................ 419 Ports .................................................................................................................... 419 Client/Server Technology Fundamentals ............................................................ 421 Client/Server Architecture ................................................................................ 421 Client/Server Communication .......................................................................... 422 Identifying a Computer ..................................................................................... 423 Testing A Program Without A Network ............................................................ 426 Socket Introduction .............................................................................................. 426 Creating A Simple Server and Client ................................................................... 428 Socket Transmission Modes ............................................................................... 432 Reading From a Socket and Writing To a Socket................................................ 434 Working With URL ............................................................................................... 437 What Is a URL .................................................................................................. 437 Creating and Manipulating URL ....................................................................... 438 Java RMI – Remote Method Invocation .................................................................. 444 RMI Applications .................................................................................................. 444 Advantage of Dynamic Code Loading ................................................................. 445 Remote Interfaces, Objects and Methods ........................................................... 445 Creating Distributed Application Using RMI ........................................................ 446 Design and Implement the components of Distributed Application .................. 446 Compile Sources and Generate Stubs ............................................................ 447 Make Classes Network Accessible .................................................................. 447 Start The Application ........................................................................................ 447 Creating RMI Server ............................................................................................ 448 Designing A Remote Interface ......................................................................... 448 RMI Technology .................................................................................................. 450 Java Database Management .................................................................................. 452 Database Management System Software ........................................................... 452 Database Connectivity ......................................................................................... 453 ODBC Application Programming Interface ( ODBC API)..................................... 453 JDBC Application Programming Interface ( JDBC API)....................................... 454 JDBC Driver Manager ...................................................................................... 455 JDBC-ODBC Bridge ......................................................................................... 455 Installing The ODBC Driver ................................................................................. 455 Connection to A Database ................................................................................... 458 Querying A Database .......................................................................................... 460 Using The Statement Object ............................................................................ 461 The Statement Object ...................................................................................... 461 The ResultSet Object ....................................................................................... 462


Java in Hindi Using PreparedStatement Object .................................................................... 465 The PreparedStatement Object ....................................................................... 465 Passing INPUT Parameter At Runtime ............................................................ 465 Java AWT – Abstract Windowing Toolkit ................................................................ 472 Event Driven Programming System .................................................................... 472 Components of an Event ..................................................................................... 473 Event Object .................................................................................................... 474 Event Source ................................................................................................... 474 Event Handler .................................................................................................. 475 Event Handling Mechanism – Double Approach ................................................. 475 The JDK 1.02 Event Model .............................................................................. 475 Delegation Event Handling Model .................................................................... 476 Event Classes .................................................................................................. 477 Event Listeners ................................................................................................ 479 Using The Delegation Event Model - Handling An Event .................................... 483 The ActionEvent Class ..................................................................................... 484 Handling Mouse Events ................................................................................... 493 Handling Keyboard Events .............................................................................. 499 Adapters ........................................................................................................... 503 Inner Classes and Anonymouse Inner Classes for Simplifying Adapter Classes ......................................................................................................................... 509 Window Fundamentals of JAVA .......................................................................... 514 Container Class ............................................................................................... 514 Panel Class ...................................................................................................... 515 Window Class .................................................................................................. 515 Frame Class ..................................................................................................... 515 Canvas Class ................................................................................................... 515 Frame Windows ................................................................................................... 516 Closing a Frame Window ................................................................................. 517 User Interface Control Fundamentals .................................................................. 519 Adding and Removing Controls ........................................................................... 520 Labels .............................................................................................................. 520 Buttons ............................................................................................................. 521 Check Boxes .................................................................................................... 522 Choice Controls ............................................................................................... 523 List Control ....................................................................................................... 524 Scroll Bars ........................................................................................................ 526 TextField Control .............................................................................................. 528 TextArea Control .............................................................................................. 530 CheckboxGroup Control .................................................................................. 531 Layout Manager ............................................................................................... 531 Menu Bars and Menus ..................................................................................... 536 Dialog Boxes .................................................................................................... 542 FileDialog Class ............................................................................................... 547 Explicit Event Handling .................................................................................... 549 Extending Buttons ............................................................................................ 550 Extending Checkbox ........................................................................................ 552 Fonts Handling In Java .................................................................................... 554 Last but not Least. There is more… ........................................................................ 558


Java in Hindi

Java Basics and Programming Fundamentals


Java in Hindi Java – Basics and Programming Fundamentals

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blfy, ,d ckj fQj Programmers dks ;s eglwl gksus yxk fd mUgsa dqN vkSj vf/kd ljy rjhds dh t:jr gS] ftlls os cMs o tfVy Programs dks Handle dj ldsaA ;s u;k rjhdk Hkh t:jr ds vuqlkj Develop fd;k x;k vkSj bl rjhds dks Object Oriented Concept dgk x;kA bl Object Oriented Concept dks /;ku esa j[k dj Programming language “C” esa


Java in Hindi fQj fodkl fd;k x;k vkSj bl fodkl dk ifj.kke “C++” Programming Language ds :i esa izkIr gqvkA gkykafd vkt Java dk ftl mn~ns”; ds fy, T;knkrj iz;ksx fd;k tk jgk gS vkSj tkok ftl izdkj dh Programming ds fy, tkuh tkrh gS] okLro esa Java dk fodkl blds fy, ugha fd;k x;k FkkA tkok dk fodkl General Electronic Equipments dks vf/kd le>nkj cukus ds fy, fd;k tk jgk Fkk] rkfd fofHkUu izdkj ds Equipments dks Artificial Intelligence iznku dh tk ldsA gkykafd ,slk rks ugha gks ldk] ysfdu tkok ,d Dynamic Internet Programming Language ds :i esa dke vkus yxhA Java dk fodkl djus okys yksx ftl Project ij dke dj jgs Fks] os mlesa “C++” Language dk iz;ksx dj jgs Fks] tks fd “C” Language dk gh fodflr :i gSA ysfdu os tks djuk pkgrs Fks] oSlk “C++” ds iz;ksx ls ugha dj ik jgs FksA blfy, mUgksaus ,d ubZ Language Develop dhA bl Language dks mUgksaus “C” o “C++” ds vk/kkj ij gh Develop fd;k gSA os Java dks ,d cgqr gh ljy Language cukuk pkgrs Fks] blfy, mUgksaus “C” o “C++” dh lHkh vklku Concepts dks T;ksa dk R;ksa mi;ksx esa fy;k vkSj tfVy Concepts dks NksM fn;kA

mUgksaus Java Language ds Programming Syntax dks Hkh yxHkx oSls gh mi;ksx esa fy;k ftl rjg ls “C” o “C++” esa fy;k tkrk gSA lkFk gh mUgksaus dbZ vU; Languages ds Concepts dk Hkh iz;ksx tkok esa fd;k rkfd blesa fdlh Hkh izdkj dk Software vklkuh ls cuk;k tk lds vkSj Software iwjh rjg ls fo”oluh; cusA bl rjg ls Java dsoy “C” o “C++” dk Modified Version gh ugha gS] cfYd dbZ vU; Languages ds Concepts ij vk/kkfjr ,d iw.kZ Programming Language gSA gkykafd blds T;knkrj Syntax o Coding Procedures “C” o “C++” Language ds vuqlkj gSa] blfy, bls “C++” Language dk Modified Version Hkh dgk tk ldrk gSA tSls&tSls t:jr cs fcuk] vxyh Generation dh Languages dks le>uk dkQh eqf”dy gSA gkykafd tkok dk fodkl ftl dke ds fy, fd;k tk jgk Fkk] ml dke ds fy, tkok mi;ksxh ugha cu ik;kA ysfdu tc tkok ds Developers us ns[kk fd bl Language dk iz;ksx Internet dh Interactive Programming esa dkQh mi;ksxh lkfcr gks ldrk gS] rc mUgksaus bl Language dks Internet ds fy, Develop djuk “kq: fd;kA os ftl Platform Independent Equipment Technology ij dke dj jgs Fks] og rduhd Internet ds fy, mi;ksxh lkfcr gks xbZA


Java in Hindi Features of JAVA

Java dsoy ,d Programming Language gh ugha gS cfYd ;s ,d Platform Hkh gSA tc Sun Microsystems us November 1995 esa Java dks nqfu;k ls ifjfpr djok;k rc Company ds Cofounder Bill Joy us Java dh fuEu ifjHkk’kk nh Fkh fd Java ,d Small, Simple, Safe, Object-Oriented, Interpreted ;k Dynamically Optimized, Byte-Coded, Architecture-Neutral, Garbage-Collected, Multithreaded Programming Language gS ftlesa Distributed, Dynamically Extensible Programs fy[kus ds fy, ,d Strongly Typed Exception-Handling Mechanism gSA tkok ds bUgha xq.akksa dks tkok ds Features Hkh dgrs gSaA

Small and Simple Java ,d NksVh vkSj ljy Hkk’kk gS ftls vklkuh ls lh[kk tk ldrk gSA tkok dks bl rjg ls Design fd;k x;k gS fd bls dksbZ Hkh Programmer vklkuh ls lh[k lds vkSj Computer Programming ds Internal Functionality dks tkus fcuk Hkh T;knk ls T;knk Efficient Program Develop dj ldsA ;fn fdlh Programmer dks fdlh Hkh Programming Language dk FkksMk Hkh Kku gS] rks og cgqr gh vklkuh ls o tYnh ls Window Based Application o Internet Based Distributed Application (Applets) Develop djuk lh[k ldrk gSA tc tkok dks igyh ckj Release fd;k x;k Fkk] rc og dkQh NksVh Hkk’kk FkhA ysfdu vkt ;s dkQh cMh Hkk’kk cu pqdh gS vkSj lHkh izdkj ds Applications dks Efficiently Develop djus esa l{ke gSA ;s Language C/C++, Simula, Ada tSlh dbZ vU; Languages ls izsfjr gS] ysfdu bldh T;knkrj Coding C++ Language ds leku gh gSA blfy, fdlh C/C++ Programmer dks tkok lh[kus esa dksbZ dfBukbZ ugha gksrh gSA bl Language esa C o C++ ds vPNs Features dks Use dj fy;k x;k gS tcfd bu Languages ds Confusing rFkk Typical Features dks NksM dj muds LFkku ij vf/kd ljy Concepts dks Include dj fy;k x;k gSA tSls C++ ds Operator Overloading o Pointer tSls Concepts dks tkok esa NksM fn;k x;k gS] tcfd Multithreading tSlh Advance Technique dks Add dj fy;k x;k gSA Object Oriented Java esa gj pht Object o Class ds :i esa ifjHkkf’kr gS] ftls Object Oriented Programming Concept dgk tkrk gSA OOPS gesa Abstraction and Encapsulation, Polymorphism vkSj Inheritance tSls Features iznku djrk gS] ftlls ge ,d leL;k dks mlh rjg ls Computer esa Logically Organize dj ldrs gSa] ftl rjg ls leL;k Real World esa Actually ;k Physically Organized jgrh gSA tkok esa cgqr lkjh t:jh Classes igys ls gh Packages ds Form esa gesa izkIr gksrh gS] ftUgsa fcuk Rewrite fd, ge T;ksa dk R;ksa Use dj ldrs gSaA


Java in Hindi Distributed Java ds Programs Network ij ;kuh Web Pages ij Hkh Execute gksrs gSaA blfy, bls Distributed Language dgk tkrk gSA Distribution dk eryc ;s gksrk gS fd Java ds Program fdlh Hkh Platform ij Run gks ldrs gSaA ge tkurs gSa fd vkt dbZ rjg ds Operating Systems miyC/k gSa vkSj vyx&vyx yksx viuh t:jr o bPNk ds vuqlkj vyx&vyx Operating Systems dk iz;ksx djrs gSaA dksbZ Windows Operating System Use djrk gS rks dksbZ Linux rks dksbZ MacOS ;k OS/2 Use djrk gSA ;s lHkh vyx&vyx Platform dgykrs gSaA ;fn ge Windows Based Computer ij dksbZ Program “C” ;k Visual Basic tSlh Hkk’kk esa Create djrs gSa] rks os Program mu lHkh Computers ij vklkuh ls Run gksrs gSa tks Windows dks Use djrs gSaA ysfdu ;fn bUgha Programs dks Linux ;k MacOS ij Execute djus dh dksf”k”k dh tk, rks ;s Program ml Operating System ij Execute ugha gksrsA bu Platforms ds fy, Program dks okil bUgha Platform okys Computers ij Compile djuk iMrk gSA tcfd Java ds lkFk ,slk ugha gSA tkok esa ge fdlh Hkh Platform ij Program Create djds Compile djsa] os Program lHkh vU; Platforms ij leku :i ls Execute gksrs gSaA ;kuh Java ds Programs dks fofHkUu Platforms ij Distribute fd;k tk ldrk gSA blfy, Java dks Distributed Language dgk tkrk gSA tkok dks bl izdkj ls Design fd;k x;k gS fd ge blesa ,sls Applications Develop dj ldsa] tks Internet ij py ldsA bl Language esa ;s Ability gS fd ;s Data o Program nksuksa dks Internet ij fofHkUu Computers ij Share dj ldrk gSA tkok Applications Remote Objects dks Hkh mruh gh vklkuh ls Access o Open dj ldrs gSa] ftruh vklkuh ls os Local Computer ds Objects dks Open o Access djrs gSaA tkok ,slh Networking dh lqfo/kk iznku djrk gS fd fofHkUu Remote Locations ij fLFkr fofHkUu Programmers ,d gh Single Project ij leku le; ij ,d lkFk dke dj ldrs gSaA Compiled and Interpreted T;knkrj vU; Languages ds Programs ;k rks Compile gksrs gSa ;k fQj Interpreted gksrs gSaA ysfdu Java ds Programs Compile Hkh gksrs gSa vkSj Interpreted HkhA Java ds Programs dks lcls igys Compile fd;k tkrk gSA Java ds Program Compile gksus ds ckn lh/ks gh Machine Language esa Convert ugha gksrs gSa] cfYd ;s Source Code o Machine Code ds chp dh fLFkfr esa Convert gksrs gSa ftls Bytecodes dgk tkrk gSA bu Bytecodes dks tc fdlh Hkh Platform ij Run djuk gksrk gS rc ;s Bytecodes ml Computer ds Platform ds vuqlkj Interpreted gks dj iwjh rjg ls ml Machine ds vuqlkj Machine Code esa Convert gksrs gSa vkSj ml Platform ij Execute gks ldrs gSaA


Java in Hindi Robust and Safe Java ds Programs esa Errors vkus dh lEHkkouk vU; Languages dh rqyuk esa fcYdqy de gksrh gSA blfy, Java ds Programs dks Robust dgk tkrk gSA blds Compiler esa fofHkUu izdkj ls Generate gksus okyh Errors dks Handle djus ds fy, dbZ Built-In rjhds Develop dj fn, x, gS vkSj tkok dks bl rjg ls Design fd;k x;k gS] fd ,d ckj lgh rjhds ls Compiled Program esa dHkh Hkh Error vkus dh lEHkkouk ugha jgrh gSA ftruh Hkh Errors vkuh gksrh gSa] os lHkh Program Development o Testing ds le; gh vk tkrh gSa] ftUgsa Handle dj fy;k tkrk gSA blesa Compile Time o Runtime nksuksa LFkkuksa ij fofHkUu izdkj ds Errors ds fy, fofHkUu Data Types dh Checking gksrh gSA fofHkUu izdkj ds Objects }kjk yh tkus okyh Memory dks ;s Lo;a gh Release dj nsrk gS] ftlls gesa bl ckr dh fpUrk djus dh t:jr ugha gksrh gS] fd geus lHkh Unrequited Objects dks Destroy djds mudh Memory dks Release fd;k ;k ughaA tkok esa Exception Handling ds fy, Hkh lqfo/kk iznku dh xbZ gS] ftldk iz;ksx ge Serious Errors dks Trap djus o mUgsa Solve djus ds fy, dj ldrs gSa] ftlls gekjs Program dh vkSj lqj{kk gks tkrh gSA tc ge Internet dh ckr djrs gSa] rc Security dkQh ek;uk j[krh gSA tkok Lo;a gh fofHkUu izdkj ds Memory Management o Memory Access ls lEcaf/kr dke djrk gS] blfy, ;s dHkh Hkh Memory o mlesa Stored Data dks xyr rjhds ls Access djus dh NwV ugha nsrk gSA bl otg ls Applet }kjk fdlh Computer esa Virus vkus dh lEHkkouk gh ugha gksrh gSA D;ksafd tkok esa Pointers dh lqfo/kk ugha gS tks Directly Memory dks Access dj lds] blfy, ge fdlh Hkh Computer dh Memory dks Directly Access ugha dj ldrs gSaA lkFk gh tkok Applets dHkh fdlh Client Computer ds Resources dks Access ugha djrs gSa] blfy, tkok Applets dHkh Hkh Clients ds Computer ;k mlds Data dks uqdlku ugha igqapk ldrs gSaA Architecture Neutral / Platform Independent / Portable / Byte Coded Java ds Bytecodes fofHkUu izdkj ds Processors o Operating Systems ij leku :i ls Run gks ldrs gSaA blfy, bls Architecture Neutral or Portable dgk tkrk gSA tkok ds Programs dks dsoy ,d gh ckj Develop djuk gksrk gSA ,d ckj bls Develop djus ds ckn bls fdlh Hkh Computer ij fdlh Hkh Platform ij Run fd;k tk ldrk gSA ;fn Operating System, System Resources ;k Processor esa Change fd;k tkrk gS] rc Hkh gesa tkok ds Program esa fdlh izdkj dk Change djus dh t:jr ugha gksrh gSA ;gh tkok ds lcls T;knk Popular gksus dh eq[; otg gS] ftlls ge tkok dk iz;ksx Internet Programming ds fy, djds World Wide Web ij Run gksus okys Applications Develop djrs gSa vkSj fofHkUu Computers dks vkil esa Interconnected djrs gq, World Wide Web ij dke djus ds fy, ,sls Programs dks Use djrs gSaA


Java in Hindi ge tkok Applet dks Remote Computer ls Download dj ldrs gSa vkSj fQj mls vius Computer ij Run dj ldrs gSaA bl izdkj dh lqfo/kk gksus ls ,d User dks mlds ?kj ij gh fofHkUu izdkj ds Applications o Applets izkIr gks tkrs gSa] ftUgsa og Use djuk pkgrk gSA tkok nks rjhdksa ls Portable gksrk gS% ,d rks tkok Compiler Byte Codes Instructions Generate djrk gS] ftls fdlh Hkh Computer ij Implement fd;k tk ldrk gS vkSj nwljk tkok ds Primitive ;k Basic Data Types Machine ij fuHkZj ugha gksrs gSa cfYd tkok Platform ij fuHkZj gksrs gSaA ;kuh fdlh Hkh Compute ij tkok ds lHkh Data Types dh Size leku gksrh gS] pkgs ge Pentium Computer ij tkok Program dks Use djsa] pkgs AMD ijA

Garbage Collective Java ,d Programmer dks Memory Manage djus dh lqfo/kk iznku ugha djrk gS cfYd t:jr ds vuqlkj Lo;a gh Memory Management djrk gSA blfy, Programmer }kjk Memory Management ds le; fdlh nwljs Data dks uqdlku igqapkus dh lEHkkouk ugha gksrh gSA blfy, ;s Language “C” o “C++” tSlh Hkk’kkvksa dh rqyuk esa vf/kd lqjf{kr ;k Secure Language gSA High Performance Java ds Program Interpreted Mode esa Run gksrs gSa ysfdu fQj Hkh vU; Interpreted Based Languages dh rqyuk esa Java dh Speed o Performance cgqr vPNh gksrh gSA blfy, bls High Performance Language dgk tkrk gSA Multithreaded and Interactive Java ;s lqfo/kk iznku djrk gS fd ,d gh Software Program ds fofHkUu Hkkxksa dks ,d gh le; esa ,d lkFk Run fd;k tk ldrk gSA blfy, bls Multithreaded Language dgk tkrk gSA mnkgj.k ds fy, ekuyks fd ge fdlh Program ls Audio Sound rks lqu gh jgs gSa] lkFk gh mlh Program esa Scroll Bars dks Hkh Use dj jgs gSaA fdlh Window esa ,d rjQ dksbZ Movie Clip rks Play gks gh jgk gS] lkFk gh ge fdlh vU; Movie Clip dks Open djus ds fy, Open Dialog Box esa fdlh nqljh Movie Clip dks Hkh [kkst jgs gSaA bl rjg ls ,d gh Program ds fofHkUu fgLlksa dk ,d gh le; esa ,d lkFk Run gksuk Multithreaded Concept ds dkj.k gh lEHko gksrk gSA Dynamic and Extensible Java esa ,d gh Program ds dbZ Versions dks ,d lkFk Maintain fd;k tk ldrk gSA blfy, bls Dynamic Language Hkh dgk tkrk gSA ;kuh tkok ,d Dynamic Language gSA tkok esa fdlh Program ds fy, Required Classes tkok ds Program ds Run gksrs le; mlesa Link gks ldrh gS vkSj tSls gh ml Class dk dke lekIr gksrk gS] og Class


Java in Hindi Lo;a gh Memory ls Release gks tkrh gSA bl izfØ;k dks Dynamic Process dgk tkrk gSA tkok ,d Query }kjk ;s Hkh Determine dj ldrk gS fd Program ds Run Time esa mlls dkSulh Class Link gks jgh gSA lkFk gh og Program ds Run Time esa Hkh fdlh Hkh Dynamic Class ;k Dynamic Link Library ls Link gks ldrk gS vkSj Run Time lqfo/kkvksa dks izkIr dj ldrk gSA bl izfØ;k dks Dynamic Linking Hkh dgrs gSaA tkok gesa vU; Languages ds Methods dks Hkh tkok esa Use djus dh lqfo/kk iznku djrk gSA bu Methods dks Native Methods dgrs gSa vkSj ;s Program ds Run Time esa Dynamically Link gks dj viuk dke djrs gSaA ;kuh ge tkok esa vU; Languages dh lqfo/kkvksa dks Use djds tkok ds Program dh {kerkvksa dks c
;s ,sls Programs gksrs gSa ftUgsa Run gksus ds fy, Browser dh t:jr gksrh gSA ;s Programs Web Pages ij Run gksrs gSaA ,d Applet Program dHkh Hkh fdlh Local Machine ds Resources dks Access ugha djrk gSA

Servlet ;s Programs Web Servers dh Functionality dks c
;kuh lHkh Objects viuh lwpukvksa dk ,d nwljs ds chp Transaction dj ldrs gSaA OOPS esa nqfu;k dh gj pht dks Object ekuk tkrk gSA ekuyks fd ,d Worker Object Money Object dks CompanyFunds Object ls ysrk gS vkSj vius Lo;a ds BankAccount Object esa tek djokrk gSA ;fn nwljk dksbZ Worker Object DoublecheckFund Object dks Use djrk gS rks Polish Object dks cqyk;k tkrk gSA Java Program dh lcls cMh ;fn dksbZ fo”ks’krk gS] rks og ;s gS fd Java ds Program dks World Wide Web Pages ij Execute fd;k tk ldrk gSA bu Programs dks Applets dgrs gSaA Java ls igys HTML Format esa gh fofHkUu Web Pages dks fy[kk tkrk FkkA ;s Web Pages ,sls gksrs Fks] ftlesa ftl Page dks ns[kuk gks mlds Hyperlink ij Click djks vkSj nwljk Page ns[kuk gS rks mlds Hyperlink ij Click djks vkSj vkxs ls vkxs c
Java in Hindi tcfd Java Applet tks fd Web Pages ij Run gksrs gSa] vf/kd vPNk vuqHko iznku djrk gSA blesa User ds Response ds vuqlkj Web Page Dynamically Update gksrk gSA tSls vkt ge dbZ TV Channel ij ns[krs gSa tgka dksbZ loky iwNk tkrk gS vkSj yksx SMS Hkst dj viuk i{k crkrs gSaA tSls&tSls yksx SMS Hkstrs jgrs gSa] SMS dh la[;k Hkh cnyrh jgrh gSA ;s dke Dynamically gksrk gS tks fd Java ds dkj.k gh lEHko gqvk gSA vkt User Internet ij miyC/k fofHkUu izdkj ds Web Pages ls Java ds dkj.k gh Interact dj ldrk gSA ;fn bldk mnkgj.k ysuk pkgsa] rks Share Market dk lkjk dke Online gksrk gSA User tc pkgs vius Account dh Information dks izkIr dj ldrk gSA ;fn og fdlh Company dk Share [kjhnuk pkgrk gS] rks og Online [kjhn ldrk gSA tSls gh og Share [kjhnrk gS] ml Company ds Buyers dh la[;k c< tkrh gSA blh rjg ls ;fn Share dks cspk tkrk gS] rks Company ds Sellers dh la[;k c< tkrh gSA ;s tks ifjorZu Web Pages ds Data esa gksrk gS] og Dynamic ifjorZu dgykrk gSA ;kuh Web Page Dynamically ;k Run Time esa User ds Interaction ls Update gksrk gSA bl izdkj dh Secure Dynamic o Online lqfo/kk gesa Java ds dkj.k gh izkIr gks ik jgh gSA gkykafd Web Based Programs dh otg ls Java vf/kd egRoiw.kZ yxrh gS ysfdu ;s ,d General Purpose Language Hkh gS ftldk iz;ksx lHkh rjg ds Programs dks Develop djus esa gksrk gSA vkt ge Mobile ds ftrus Hkh Software ns[krs gSa muesa ls T;knkrj Java Based gSaA Mobile esa tks Games Run gksrs gSa os T;knkrj Java esa Develop fd, tkrs gSaA

Java – Working

tc Java ds fdlh Program dks Compile fd;k tkrk gS rc Java dk Program iwjh rjg ls Machine Language esa Convert ugha gksrk gS cfYd ,d Intermediate Language esa Convert gksrk gS] ftls Java Bytecodes dgk tkrk gSA ;s Codes Platform Independent gksrs gSa] blfy, bUgsa fdlh Hkh Operating System o fdlh Hkh Processor ij pyk;k tk ldrk gSA Java ds Program dh Compilation dsoy ,d gh ckj gksrh gS ysfdu ftruh ckj Hkh Java ds Program dks pyk;k tkrk gS] gj ckj ml Program dk Interpretation gksrk gSA bls ge fuEu fp= }kjk le> ldrs gSa&

Java Bytecodes dks ge Java Virtual Machine (Java VM) ds fy, Machine Codes eku ldrs gSaA gj Java Interpreter pkgs og Java Development Tool gks ;k dksbZ Browser tks fd Java Applets dks Run djrk gks] Java Virtual Machine dk gh Implementation gSA Java Virtual Machine dks Hardware esa Hkh Implement fd;k tk ldrk gS] ftldk ifj.kke vkt ds Mobile System Software gSaA


Java in Hindi Java Bytecodes gesa ;s lqfo/kk nsrs gSa fd ge Java ds Program dks ,d ckj Compile djsa vkSj dgha Hkh Run djsaA ge fdlh Java Program dks fdlh Hkh ml Computer ij Compile dj ldrs gSa ftl ij Java Compiler gksA fQj ml Java Program ds Bytecodes dks fdlh Hkh ml Computer ij Run fd;k tk ldrk gS ftl ij Java VM gksA

mnkgj.k ds fy, ,d gh Java Program Windows, OS/2 MacOS NT, Macintosh vkfn fofHkUu Platform ij Execute gks ldrs gSaA

Java Platform

Platform ,d ,d ,slk Software ;k Hardware Environment gksrk gS ftlesa dksbZ Program Run gksrk gSA Java Platform dbZ vU; Platforms ls vyx gSA Java Platform ,d Software Platform gS] tks lHkh vU; Hardware Based Platform ds Top ij ;kuh Åij Run gksrk gSA T;knkrj vU; Platforms Hardware o Operating System dk Combination

gksrs gSaA

Java Platform ds nks Components gSaA igyk gS Java Virtual Machine (Java VM) ftlds ckjs esa ge tku pqds gSaA ;s Java Platform dk Base ;k vk/kkj gS vkSj fofHkUu Hardware Base Platform ds Åij jgrk gSA nwljk gksrk gS Java Application Programming Interface (Java API) ftlds ckjs essa ge vc tkusaxsA Java API Ready Made Software Components dk ,d cgqr cMk Collection gS tks fd Programmer dks GUI (Graphical User Interface) tSlh dbZ mi;ksxh {kerk,a iznku djrk gSA Java API dks Related Components dh Libraries ds :i esa Group dj fn;k x;k gSA bu fofHkUu Related Components ds Group dks gh Packages dgrs gSaA ,d Java Program

dks ge fuEu fp=kuqlkj n”kkZ ldrs gSa%

tc ,d Java Program dks fdlh Computer ij Execute fd;k tkrk gS rks Java Program o Hardware Based Platform ds chp Java API o Java Virtual Machine dh Layer gksrh gSa tks Java ds Program dks Hardware Dependencies ls vyx djrh gSaA


Java in Hindi ;kuh bu nksuksa dh otg ls Java dk dksbZ Program fdlh Hkh Computer ds Hardware ij fuHkZj ugha gksrk gSA ,d Platform Independent Environment ds :i esa Java dk Program vU; Native Codes Programs dh rqyuk esa dqN /khek gksrk gSA ysfdu fQj Hkh vPNs Compilers, Java ds lkFk vPNh rjg ls Tune gksus okys Interpreters vkSj Bytecodes Compilers dh otg ls Java dh Performance dks Native Code dh Performance ds vkl&ikl yk;k tk ldrk gS vkSj oks Hkh tkok dh lHkh fo”ks’krkvksa ds lkFkA Java Programs dk lcls vf/kd tkuk igpkuk ;fn dksbZ :i gS rks og Java Applets dk gSA ,d Applet Hkh ,d Java Program gh gksrk gS ysfdu bldh fo”ks’krk ;s gS fd ;s fdlh Java Enabled Browser tSls fd Internet Explorer, Google Chrome, Firefox, Safari, Opera vkfn esa Run gksrk gS] Lora= :i ls ;s Run ugha gks ldrkA tcfd Java Application Standalone Run gks ldrs gSaA Applets Application ds leku gh gksrs gSaA ,slk Hkh ugha gS fd Java dk iz;ksx dsoy Web Pages Applications fy[kus ds fy, gh fd;k tk ldrk gSA cfYd Java ,d Powerful Software Platform vkSj General Purpose High Level Programming Language Hkh gSA Java ds lcls Common Application Programs ds mnkgj.k Servers gSa tks fdlh Network ds fofHkUu Clients dks Service iznku djus dk dke djrs gSaA Web Servers, Proxy Servers, Mail Servers, Print Servers o Boot Servers Java Applications ds fofHkUu mnkgj.k gSaA Servlets Applets ds leku gh gksrs gS]a ysfdu fdlh Browser esa Run gksus ds ctk; ;s Java Servers esa Run gksrs gSa vkSj Java Server dh Configuring ;k Tailoring djrs gSaA

,d loky iSnk gks ldrk gS fd Java API bu lHkh izdkj ds Programs dks fdl izdkj ls Support djrk gSA bldk tokc ;s gS fd ;s bu lHkh izdkj ds Programs dks ,d Software Components ds Package ds ek/;e ls Support djrk gS ftlesa fofHkUu izdkj dh Functionalities gksrh gSaA Core API ,d ,slk API gS tks gj Java Platform esa iwjh rjg ls Implemented gksrk gSA Core API gesa fuEu Features iznku djrk gS& The Essentials:

Objects, strings, threads, numbers, input and output, data structures, system properties, date and time tSlh dbZ phtksa dks Handle djus dh lqfo/kk iznku djrk gSA

Applets:

Java applets cukus ds fy, fofHkUu Components iznku djrk gSA

Networking: Networking dh lqfo/kk izkIr djus ds fy, URLs, TCP o UDP sockets rFkk IP addresses iznku djrk gSA Internationalization: ;s gesa ,slh lqfo/kk iznku djrk gS fd ge ,sls Programs fy[k ldrs gSa tks lkjh nqfu;k esa leku :i ls py ldrk gSA 24 Any Question or Suggestion, Just Discuss Here...

Java in Hindi Security: ;s gesa Low-level vkSj high-level nksuksa izdkj dh lqj{kk iznku djrk gSA lkFk gh electronic signatures, public/private key management, access control vkSj certificates dh Hkh lqfo/kk iznku djrk gSA Software components: ;s gesa JavaBeans tSls Components iznku djrk gS tks fdlh igys ls cus gq, Component Architecture esa tSls fd Microsoft's OLE/COM/Active-X architecture, OpenDoc vkSj Netscape's Live Connect esa Plug in gks ldrk gSA Object serialization: ;s gesa Remote Method Invocation (RMI) }kjk nwljs ljy midj.kksa ls Communication djus dh lqfo/kk iznku djrk gS] ftldk iz;ksx vkt Mobile Technology esa Hkh gks jgk gSA Java Database Connectivity (JDBC): ;s gesa Relational databases ls Connect gksus o mUgsa Access djus dh lqfo/kk iznku djrk gSA Java esa dsoy Core API gh ugha gSa cfYd dqN Standard Extensions Hkh gSaA ;s Standard Extensions 3D, Servers, Collaboration, Telephony, Speech, Animation o dbZ vU; phtksa ds fy, Hkh APIs Define djrs gSaA

Program

Computer Program ,d rjhdk gS tks Computer dks ;s crkrk gS fd mls dc, D;k djuk gSA Computer ds Boot gksus ls ysdj Shut Down gksus rd tks Hkh dqN gksrk gS] fdlh uk fdlh Program dh otg ls gksrk gSA MS-Word ,d Program gS] Norton Antivirus ,d Program gS] DOS Prompt ij fy[kk tkus okyk gj Command ,d Program gS] ;gka rd fd fofHkUu izdkj ds Computer Viruses Hkh ,d Program gSaA

vkt Artificial Intelligence dk ,d mnkgj.k Robots gSaA bu Robots dks vehj yksx vius ?kjksa esa j[krs gSaA ;s Robots ,sls gksrs gSa fd bUgsa tks dke djus ds fy, dg fn;k tkrk gS ;k fdlh rjhds ls crk fn;k tkrk gS] ;s Robots os lHkh dke cMh gh vPNh rjg ls dj ysrs gSaA tSls ;fn vki bu [kksyuk gSA rks ;s ftlesa vki fdlh ckr ekurk gS vkSj

Robots dks dgsa fd tc vkids ?kj dh Bell Ring gks rks bUgsa ?kj dk njoktk oSlk gh djrs gSaA ;s Computer Program dk ,d lk/kkj.k lk mnkgj.k gS futhZo Robot dks dqN Instruction nsrs gSa] vkSj og futhZo Robot vkidh

vkids }kjk crk;k x;k dke dj nsrk gSA

blh rjg ls Computer dks Hkh fofHkUu izdkj ds Instructions iznku fd, tkrs gSa] ftuds vuqlkj Computer dke djrk gSA tSls fd Microsoft Company us Windows ds Program


Java in Hindi }kjk Computer dks ;s Instruction fn;k gS fd ;fn dksbZ Mouse dks Move djrk gS] rks Monitor dh Screen ij fLFkr Cursor ;k Pointer Hkh mlh rjg ls Move gksuk pkfg,A ;fn dksbZ Start Button ij Click djrk gS rks Start Menu Popup gksuk pkfg,] vkfn&vkfnA ;kuh Computer ij ge tks dksbZ Action djrs gSa] mls Response djus ds fy, igys ls gh Program fy[kk x;k gSA tc dksbZ Event gksrk gS] Computer ml Event ls lEcaf/kr Program ds vuqlkj dke djus yxrk gS vkSj gesa gekjk Required Result iznku djrk gSA Computer esa tks Hkh dqN gksrk gS mls Event dgrs gSaA tSls ;fn ge Mouse dks Move djrs gSa rks MouseMove Event Generate gksrk gS] ;fn ge Mouse ls Click djrs gSa rks MouseClick] Event Generate gksrk gSA blh rjg ls ;fn ge Keyboard ij dksbZ Key Press djrs gSa rks Keypress Event Generate gksrk gSA

;s rks Hardware Events ds mnkgj.k gSaA Computer esa Software Events Hkh Generate gksrs gSa ftUgsa Response djus ds fy, Hkh fofHkUu izdkj ds Programs fy[ks x, gSaA mnkgj.k ds fy, fdlh Window dks Minimize djuk] Restore djuk] fdlh Window dks Close djuk vkfn Software Events ds mnkgj.k gSaA fuEu Program nsf[k,& #include main() { printf("Hello Gopala"); }

bl Program }kjk ge gekjs Computer dks dsoy ,d Message Screen ij Print djus ds fy, ,d Instruction iznku dj jgs gSaA ;s Program Computer Screen ij “Hello Gopala” Print djrk gSA ge fdlh Computer Program esa ftruh Hkh Coding Lines fy[krs gSa] ;s lHkh Lines Program Statements dgykrh gSaA Computer mu lHkh Statements dks ,d fuf”pr Øe esa Handle djrk gS] Bhd mlh rjg ls ftl rjg ls ,d jlksbZ;k fdlh fo”ks’k izdkj ds idoku dks cukus ds fy, ,d fo”ks’k Øe dk ikyu djrk gSA pwafd Computer mlh Øe esa fofHkUu Statements ds vuqlkj dke djrk gS ftl Øe esa ,d Programmer fdlh Program dks fy[krk gSA blfy, ;fn dksbZ Program oSlk Result iznku ugha djrk] tSlk ,d Programmer pkgrk gS] rks ;s Computer dh xyrh ugha gS cfYd ml Program dh Mistake gSA T;knkrj Program mlh rjg ls fy[ks tkrs gSa] ftl rjg ls ge dksbZ Letter fy[krs gSa] ftlesa fdlh Word Processor esa ge gj Word dks Type djrs gSaA dqN Programming Languages ds Compilers ds lkFk muds [kqn ds Word Processors vkrs gSa] tSls fd Turbo C++ dk Program Creation dk iwjk IDE vkrk gS tcfd dqN Compilers ds lkFk dksbZ Word Processor ugha vkrkA ftu Compilers ds lkFk dksbZ Word Processor ugha vkrk ftlesa Program dh Coding dh tk lds] rks ,sls Program ds Source Code fy[kus ds fy, fdlh Hkh vU; Word Processor


Java in Hindi dk iz;ksx fd;k tk ldrk gSA ge Java Developer Kit ds lHkh Components dk iz;ksx fdlh Hkh Word Processor tSls fd Notepad ;k WordPad ds lkFk dj ldrs gSaA tc ,d Program ds Source Codes fy[k fy, tkrs gSa] rks mlds ckn ml Source File dks ml Language ds Extension ds lkFk Save djuk gksrk gSA tSls ;fn ge Notepad dk iz;ksx djds “C” Language dk Program fy[krs gSa rks File dks Save djrs le; gesa File ds uke ds ckn .C Extension nsuk gksrk gSA mlh rjg ls ;fn ge Java ds Program dks Save djrs gSa] rks gesa File ds uke ds ckn .java Extension dk iz;ksx djuk gksrk gSA tSls Program.java, Application.java vkfnA ge tks Program fy[krs gSa os English ds dqN lkekU; Words gksrs gSaA ysfdu Computer dsoy Binary Language dks gh le>rk gSA blfy, gesa ,d ,sls Program dh t:jr gksrh gS tks gekjs Source Codes dks Computer ds le>us ;ksX; Machine Language esa Convert dj ldsA Interpreter ,d ,slk Program gS tks fdlh Hkh Program dh Source File ds gj Statement ;k Code dh gj Line dks Computer dh Machine Language esa Convert djds Computer dks crkrk gS fd mls D;k djuk gSA

dqN Languages esa ,d vU; Software ftls Compiler dgrs gSa dk iz;ksx djds Source Code File dks Machine Language esa Convert djrk gSA bu nksuksa esa vUrj dsoy bruk gS fd Interpreter Source File ds gj Line ;k gj Statement dks Computer ds le>us ;ksX; Binary Language esa Convert djrk gS vkSj ;fn fdlh Statement esa dksbZ Error gks rks ml Line ;k Statement ls vkxs Interpret ugha gksrkA tcfd Compiler ,d ,slk Program gksrk gS tks iwjs Program dks ,d lkFk Machine Language esa Convert djrk gSA ;fn Program esa dksbZ Error gks rks Program lHkh Errors dks ,d lkFk Display djrk gS vkSj rc rd Program dks Machine Language esa Convert ugha djrk gS tc rd fd lHkh Errors dks Debug uk dj fn;k tk,A tks Program Interpreted gksrs gSa os Compiled Program dh rqyuk esa /khjs pyrs gSaA ysfdu Java ,d ,slh Language gS ftldks Interpreter o Compiler nksuksa dh t:jr gksrh gSA tc Hkh ge dksbZ Program fy[krs gSa rks mlesa fdlh uk fdlh rjg dh Errors gesa”kk vkrh gSA bu Errors dks Computer Programming dh Hkk’kk esa Bug dgk tkrk gS vkSj bu Errors dks lgh djus ds Process dks Debug djuk dgrs gSaA

Procedural Techniques and OOPS

Pascal, C, Basic, Fortran tSlh ikjEifjd Hkk’kk,a Procedural Languages ds mnkgj.k gSa] ftlesa izR;sd Statement Computer dks dqN djus dk vkns”k nsrk gSA ;kuh Procedural Languages Instructions dk ,d lewg gksrk gSA Procedural Languages esa NksVs Programs ds fy;s fdlh Hkh vU; izdkj ds Pattern dh vko”;drk ugh gksrh gSA Programmer Instructions dh List cukrk gS vkSj Computer muds vuqlkj dke djrk gSA

tc izksxzke dkQh cMs o tfVy gks tkrs gSa] rc Instructions dh ;g List dkQh ijs”kkuh iSnk djrh gSA blfy;s ,d cMs izksxzke dks NksVs&NksVs VqdMksa esa ckaV fn;k tkrk gSA bu NksVs&NksVs 27 Any Question or Suggestion, Just Discuss Here...

Java in Hindi VqdMksa dks Functions dgk tkrk gSA Functions dks nwljh vU; Hkk’kkvksa esa Subroutine, Subprogram ;k Procedure dgk tkrk gSA ,d cMs izksxzke dks NksVs&NksVs Functions esa foHkkftr djus ls iwjk Program Functions dk ,d lewg cu tkrk gSA bls Module dgk tkrk gSA ysfdu ;s Modules Hkh Procedural Programming esa gh vkrs gaS D;ksafd lHkh Functions esa Statements dh ,d List gksrh gS vkSj lHkh Functions fey dj iwjk Program cukrs gSa] ftlls iwjk Program Instructions dh ,d cgqr cMh List cu tkrh gSA Procedural Languages ds “kq:vkrh nkSj esa buesa gh Program Develop fd, tkrs FksA “C” Hkh ,d Procedural Languages gS vkSj tc “C” Hkk’kk dk vkfo’dkj gqvk Fkk rc Programmers vU; Hkk’kkvksa dks NksM dj “C” esa gh vius Program Develop djus yxs FksA

ysfdu le; o vko”;drk ds vuqlkj tc Program cMs o tfVy gksus yxs] rc Programmers dks bl Hkk’kk esa izksxzke cukus esa fnDdrsa vkus yxhaA mUgksus eglwl fd;k fd bl Hkk’kk esa dqN lq/kkj dh vko”;drk gS rkfd ;s Hkk’kk ljy o yksdfiz; cu ldsA ;s Hkk’kk ljy cu lds blds fy;s bldk okLrfod thou ds vuqlkj gksuk t:jh FkkA ;kuh ge gekjs lkekU; thou esa ftl izdkj ls O;ogkj djrs gSa] bl Hkk’kk dk Hkh oSlk gh gksuk t:jh Fkk rkfd Programmers blesa vf/kd ljyrk o lQyrk ls Program cuk ldsaA Hkk’kk okLrfod thou ds vuqlkj gks] ;gh Concept Object Oriented Programming ;kuh OOP dk vk/kkj cukA “C” Hkk’kk dh bu dfe;ksa dks igpkuk x;k vkSj blesa lq/kkj fd;k x;kA QyLo:i gesa “C” Hkk’kk dk ,d u;k laLdj.k “C++” izkIr gqvk tks fd Object Oriented Concept ij vk/kkfjr gSA vko”;drk ds vuqlkj bl Hkk’kk dh dfe;ksa dks Hkh igpkuk x;k vkSj mlesa lq/kkj djus ij tks ubZ Hkk’kk lkeus vkbZ og Java FkhA vkb;sa] ge Hkh tkuus dh dksf”k”k djrs gSa fd “C” Hkk’kk esa ,slh dkSulh dfe;ka Fkha] ftuesa lq/kkj dh vko”;drk eglwl dh xbZ \ Procedural Languages esa dke gksus dk egRo Fkk Data dk ugha] ;kuh fd Keyboard ls Data Input fd;k tk,] Data ij Processing dh tk,] Errors dks Check fd;k tk, vkfnA Functions esa Hkh blh egRo dks tkjh j[kk x;kA Functions dksbZ dke djrs gSa] mlh izdkj ls ftl izdkj ls lk/kkj.k Statement djrk gSA Functions dksbZ tfVy dke Hkh dj ldrs gSa

ysfdu buesa Hkh dke ds gksus dk gh egRo FkkA

iwjs Program esa Data ij dksbZ /;ku ugha fn;k tkrk Fkk tcfd iwjs izksxzke dk ewy vk/kkj Data gh gksrk gSA fdlh Inventory ds Program esa bl ckr dk dksbZ T;knk egRo ugha gksrk gS fd Data dks fdl izdkj ls Display fd;k tkrk gS ;k ,d Function fdl izdkj ls Corrupt Data dks Check djrk gS] cfYd bl ckr dk gksrk gS fd Data D;k gS vkSj og fdl izdkj ls Program esa dke vk jgk gSA Procedural Program esa Data dks f}rh; Lrj ij j[kk x;k Fkk tcfd fdlh Hkh Program dk ewy vk/kkj Data gh gksrk gSA mnkgj.k ds fy;s] fdlh Inventory ds Program esa fdlh Data File dks Memory esa Load fd;k tkrk gS] rc ;s File ,d Global Variable dh rjg gksrh gS] ftls dksbZ Hkh Function Use dj ldrk gSA ;s Functions Data ij fofHkUu izdkj ds Operations djrs gSaA ;kuh ;s Data dks Read djrs gS] Analyze djrs gSa] Update djrs gSa] Rearrange djrs gSa] Display djrs gSa vkSj okil Disk ij Write djrs gSaA “C” esa Local Variables Hkh gksrs gSa ysfdu Local Variables, egRoiw.kZ Data ds fy;s brus mi;ksxh ugha gksrs gSa] tks fd fofHkUu Functions }kjk Access fd, tkrs gSaA 28 Any Question or Suggestion, Just Discuss Here...

Java in Hindi eku yksa fd ,d u, Programmer dks Data dks fdlh [kkl rjhds ls Analyze djus ds fy;s ,d Function fy[kus dks dgk x;kA izksxzke dh tfVyrk ls vufHkK Programmer ,d ,slk Function cukrk gS] tks fd vpkud fdlh egRoiw.kZ Data dks u’V dj nsrk gSA ,slk gksuk dkQh vklku gS D;ksafd dksbZ Hkh Function Data dks Access dj ldrk gSA blfy;s D;ksafd Procedural Language esa Data Global gksrk gSA ;s dqN ,slk gh gS tSls fd vki vius Personal dkxtkr dks Telephone Directory ds ikl j[k nsa tgka dHkh Hkh dksbZ Hkh igqap ldrk gS] mlls NsMNkM dj ldrk gS vkSj mls u’V dj ldrk gSA blh izdkj ls Procedural Languages esa gksrk gS tgka vkidk Data Global gksrk gS vkSj dksbZ Hkh Function mls Use djds [kjkc dj ldrk gS ;k uqdlku igqapk ldrk gSA Procedural Languages dh nwljh deh ;s Fkh fd dbZ Functions ,d lkFk ,d gh Data dks Use dj jgs gksrs gSa] blfy;s Data dks Store djus dk rjhdk dkQh tfVy gks tkrk gSA leku Data dks Use dj jgs lHkh Functions dks Modify fd, fcuk Data esa fdlh izdkj dk dksbZ

ifjorZu ugha fd;k tk ldrk gSA

mnkgj.k ds fy;s ;fn vki ,d u;k Data Add djrs gSa rks mu lHkh Functions dks Modify djuk gksxk tks fd Data dks Use dj jgs gSa] rkfd ;s lHkh Functions Add fd, x, u, Data dks Use dj ldsaA ;s irk djuk fd dkSu&dkSu ls Function Data dks Use dj jgs gSa vkSj lHkh dks fcYdqy lgh rjhds ls Modify djuk dkQh dfBu gksrk gSA Procedural Programs dks Design djuk dkQh eqf”dy gksrk gSA leL;k ;s gksrh gS fd Design okLrfod thou ls Related ugha gksrk gSA tSls fd] ekuk vki ,d Graphics Interface esa Menus, Windows ds fy;s Code fy[kuk pkgrs gSa] rks vkidks ;s r; eqf”dy gksxk fd dkSuls Functions Use fd, tk,\ dkSulk Data Structure Use fd;k

vkfnA budk dksbZ Li’V mRrj ugha gSA

budk

User

djuk tk,\

Procedural Programs ds lkFk dbZ vkSj ijs”kkfu;ka gSaA muesa ls ,d leL;k u, Data Type dh gSA Computer Languages esa dbZ izdkj ds Built-in Data Types gksrs gSa] tSls fd Integer, Float, Character vkfnA ekuyks fd vki Complex Numbers ds lkFk izfØ;k djuk pkgrs gSa ;k Two-dimensional Coordinates ds lkFk dke djuk pkgrs gSa ;k Data ds lkFk izfØ;k djuk pkgrs gSaA Built-in Data Type budks vklkuh ls Handle ugha dj ldrs gSaA

blfy, gesa gekjh vko”;drkuqlkj Lo;a ds Data Type cukus dh t:jr gksrh gSA Procedural Language esa Lo;a ds Data Type cuk dj ge mUgs fcYdqy Built-in Data Type dh rjg Use ugha dj ldrs gSaA Procedural Language brus mUur ugha gSaA fcuk vizkd`frd tfVy rjhdksa ds vki Procedural Languages esa x o y nksuksa Coordinates dks ,d gh Variable esa Store djds ml ij Processing ugha dj ldrs gSaA Procedural Languages dks fy[kuk o Maintain djuk dkQh eqf”dy dke gksrk gSA

The Object-Oriented Approach

Object Oriented Language dk ewyHkwr fopkj ;s gS fd ftl leL;k dk lek/kku Computer ij izkIr djuk gS ml leL;k ds ewy Data vkSj ml Data ij dke djus okys Functions dks Combine djds ,d Unit ds :i esa ys fy;k tkrk gSA bl Unit dks Object dgk tkrk gSA


Java in Hindi ,d Object ds Data ij dke djus ds fy;s fy[ks x, Operations ;k Functions dks Java esa Methods dgk tkrk gSA ;s Methods fdlh Object ds Data dks Access djus dk ,d ek= ek/;e gksrs gSaA ;fn vki fdlh Object ds vUnj j[ks fdlh Data dks Read djuk pkgrs gSa] rks vkidks blh Object ds vUnj Define fd, x, ml Method dks Use djuk iMrk gS] ftls ml Object ds Data dks Access djus ds fy;s gh ifjHkkf’kr fd;k x;k gSA ;gh ,d Method gksrk gS ftldh enn ls vki ml Object ds Data dks Read dj ldrs gSaA vki lh/ks gh Data ds lkFk fdlh izdkj dh izfØ;k ugha dj ldrs gSa D;ksafd Data Hidden jgrk gSA blfy;s fdlh izdkj ls vpkud gq, ifjorZu ls Data lqjf{kr jgrk gSA Data o Data dks Use dj ldus okys Functions ;k Operations dk ,d lkFk ,d gh Unit ds :i esa gksuk Encapsulation dgykrk gSA Data dk Hidden jguk ;kuh Data Hiding o Encapsulation Object Oriented Programming dk ewy rF; ;k Key Terms gSA ;fn vki fdlh Data dks Modify djuk pkgrs gSa] rks vkidks irk gksuk pkfg, fd dkSulk Method ml Data ij Required Operation djus dh {kerk j[krk gSA dksbZ Hkh vU; Method ml Data dks Access ugha dj ldrk gSA ;s Processing Program dks fy[kuk] Debug djuk o Maintain djuk vklku cukrh gSA

,d Java dk izksxzke
fd [kkuk [kkus okys esgekuksa dh la[;k lhfer gksA ysfdu ;fn esgekuksa dh la[;k vf/kd gks rks ;s rjhdk Bhd ugha dgk tk ldrk gSA

D;ksafd tc esgeku vf/kd gksaxs rks Table Hkh cMk gksxk vkSj [kkus ds fofHkUu lkeku iwjs Table ij dkQh nwj&nwj gksaxsA ,sls esa ;fn dksbZ esgeku fdlh nwj j[ks O;atu rd igqapus dh dksf”k”k djrk gS] rks gks ldrk gS fd dksf”k”k djrs le; mlds Shirt dh Sleeves fdlh nwljs esgeku ds [kkus esa pyh tk, ;k ,slk Hkh gks ldrk gS fd dbZ esgeku ,d lkFk fdlh ,d gh O;atu ij gkFk c

Java in Hindi bl leL;k ds lek/kku ds :i esa ;fn dbZ NksVs&NksVs Tables gksa vkSj mu ij ,d lhfer ek=k esa esgeku gksa vkSj lcds ikl mudk viuk Hkkstu gks] rks ;s ,d vPNh O;oLFkk gks ldrh gSA bl NksVs Table ij lHkh esgeku fdlh Hkh O;atu ij vklkuh ls igqap ldrs gSaA ;fn dksbZ esgeku fdlh vU; Table ij j[ks fdlh O;atu dks ysuk pkgrk gS rks lEHkor;k og fdlh vU; esgeku ls ml O;atu dks ykus ds fy;s dg ldrk gSA ;s rjhdk Object Oriented Programming dk gS ftlesa gjsd NksVh Table dks ,d Object dgk tk ldrk gSA gjsd Object esa mldk Lo;a dk Data vkSj Data ij Perform gksus okyk Operation ;k Function gksrk gSA Data o Operations ds chp gksus okys fofHkUu ysu&nsu vf/kdrj Object ds vUnj gh gksrs gSa ysfdu vko”;drkuqlkj ;s Hkh lEHko gS fd fdlh vU; Object ds Data dks Hkh Use fd;k tk ldsA pwafd ,d Object ds Data dks dsoy ogh Object Access dj ldrk gS] blfy, ;fn fdlh Object A ds Data dks dksbZ nwljk Object B Access djuk pkgrk gS] rks og Object B Object A ls Data dks Access djus ds fy, dgrk gSA bl izfØ;k dks Message Passing djuk dgrs gSaA Object A Object B dh Request dks iwjk djrk gS vkSj vius Data dks Access djds djus ds fy, ml nwljs Object B dks ns nsrk gSA

Difference Between C++ and Java

okLro esa Java “C” o “C++” dk gh Modified :i gSA pwafd vkt Hkh T;knkrj Professional yksx cMs Projects ds fy, “C++” dks gh pqurs gSa] blfy, ;s tkuuk t:jh gS fd Java esa “C++” dh fdu fo”ks’krkvksa dks fy;k x;k gS vkSj fdu phtksa dks NksMk x;k gS tks lkekU; Programmer dks ijs”kku djrh gSaA Preprocessor “C” o “C++” esa Program ds Compilation dks Control djus ds fy, Preprocessors dk iz;ksx fd;k tkrk gSA “C++” dk Compiler fdlh Hkh Source Program dks Compile djus ls igys lHkh Preprocessor Directives dks Expand djus dk dke djrk gSA lHkh “C” o “C++” ds Programmers tkurs gSa fd Preprocessors dk iz;ksx djus ij Program dh tfVyrk c< tkrh gSA “C++” ds Programmer Preprocessors dk iz;ksx djds yxHkx Lo;a dh Language cukuk “kq: dj nsrs gSaA T;knkrj Statement ds fy, o Constant ekuksa ds fy, os Preprocessors dk iz;ksx djrs gSaA blls Program dh tfVyrk bruh c< tkrh gS fd dksbZ Hkh u;k Programmer ;fn ml Program dks le>uk pkgs rks mls dkQh ijs”kkuh vkrh gSA lkFk gh bu Program Codes dks Reuse Hkh ugha fd;k tk ldrk gSA Preprocessor Directives dh ,d deh ;s Hkh gS fd budh Type Checking dHkh Hkh fuf”pr ugha gksrhA ;kuh ;s gesa”kk ,d String Format dks Follow djrs gSaA ;fn ge #define MAX 10 Statement fy[krs gSa] rks ;gka eku 10 Integer ugha cfYd ,d String gksrk gSA Java esa Preprocessors dks gVk fn;k x;k gSA gkykafd Java Preprocessor Directives ds leku gh Functionality iznku djrk gS ysfdu vf/kd Control ds lkFkA Java esa #define ds LFkku ij Constant Data Members dk iz;ksx fd;k tkrk gSA


Java in Hindi bldk ifj.kke ;s gS fd Java ds Codes dks iuk “C++” ds Codes dks ius dh rqyuk esa vf/kd ljy gks tkrk gSA lkFk gh Java ds Programs esa Header Files dk iz;ksx ugha gksrk gS cfYd Java dk Compiler Source Code File ls lh/ks gh Class Definitions cuk ysrk gS ftlesa Class Definitions o Methods nksuksa gksrs gSaA Pointers ftrus Hkh “C” ;k “C++” ds Programmers gSa] os lHkh ekurs gSa fd ;fn Pointers dks iwjh lko/kkuh ls iz;ksx uk fd;k tk, rks ,sls Errors Generate gksrs gSa] ftUgsa Debug djus esa fnekx dk ilhuk fudy tkrk gSA lkFk gh Pointers ds iz;ksx ls Program gesa”kk le>us esa tfVy gks tkrk gS] gkykafd Pointers ds iz;ksx ls gekjk Program Directly Memory Locations dks Access dj ldrk gS] blfy, Program dh Speed rqyuk esa rst gks tkrh gSA “C++” ds Programmers gesa”kk Dynamic Data Structure dks Create o Maintain djus ds fy, Pointers Arithmetic dk iz;ksx djrs gSa vkSj gesa”kk tfVy Bugs esa Qalrs gSaA “C++” Programmers dk T;knkrj le; mu Programs dks Create djus esa ugha chrrk ftuesa Pointer dk iz;ksx gksrk gS] cfYd mu Programs dks Debug djus esa chrrk gSA Java Pointers dks Support ugha djrk gSA ;kuh Java esa Pointes tSlh dksbZ O;oLFkk ugha gS tks Directly Memory dks Access dj ldsA gkykafd Pointers ds LFkku ij Java esa References dk cgqr iz;ksx fd;k tkrk gS tks fd Pointers ds leku gh dke djrs gSa ysfdu References dk Arithmetic lkekU; Arithmetic tSlk gh gksrk gS uk fd Pointer Arithmetic

tSlkA

bl Process ls mu lHkh Errors ls NqVdkjk fey tkrk gS tks Pointers ds Mismanagement ds dkj.k Generate gksrh gSaA References dk iz;ksx djus ls Java ds Program i;kZIr Readable o le>us ;ksX; gksrs gSa tcfd Pointers dk pkgs iwjh rjg ls lgh iz;ksx fd;k tk,] ysfdu Program vklkuh ls le>us ;ksX; o Readable ugha gksrk gSA “C” o “C++” ds Programmers lksap ldrs gSa fd os tks dke Pointers dk iz;ksx djds dkQh vklkuh ls dqN Data Structures dks Implement dj ldrs Fks os dke Java esa ugha fd, tk ldsaxsA tSls fd Dynamic Arrays Java esa Create ugha gks ldrsA ysfdu ,slk ugha gSA okLrfodrk ;s gS fd os lHkh dke Java esa Objects o Objects ds Array ds iz;ksx ls vf/kd vklkuh o Reliability ds lkFk fd, tk ldrs gSaA Java gesa dqN Runtime Security Hkh iznku djrk gS tks dksbZ vU; Language Provide ugha djrhA tSls fd ;fn ge “C” ;k “C++” esa fdlh Array dh Size dks 10 Define fd;k gS vkSj ge 11th Index Number ij dksbZ eku Input djuk pkgsa rks Java gesa ,slk ugha djus nsrk tcfd “C” o “C++” esa ge ,slk djds fdlh nwljs Data dks Damage dj ldrs gSaA

Structure and Union “C” esa nks rjg ds (Structure and Union) vkSj “C++” esa rhu rjg ds (Structure Union and Class ) Complex Data Types gSaA Java esa dsoy ,d gh Complex Data Type gS ftls Class dgrs gSaA “C” o “C++” esa ftrus dke bu rhuksa dks iz;ksx djds fd, tkrs gSa Java esa os lHkh dke dsoy ,d Class ls gh fd;k tk ldrk gSA tc gesa Structure ;k Union ds Functionality dh t:jr gksrh gS rks Java gesa bu Functionality dks Class }kjk izkIr djus ds fy, ck/; djrk gSA 32 Any Question or Suggestion, Just Discuss Here...

Java in Hindi gkykafd ,slk yx ldrk gS fd Java esa Programmers dks Structure o Union ds LFkku ij Class Use djus ds fy, Extra dke djuk iMsxk ysfdu ,slk ugha gSA cfYd Class ds iz;ksx ls Program dh tfVyrk de gks tkrh gSA Java cukus okyksa us blh ckr dks izkFkfedrk nh gS fd ftruk gks lds mruk Java dks Simple o vklkuh ls le>us ;ksX; Language esa j[kk tk,] blfy, Java esa ls “C” o “C++” dh mu phtksa dks gVk fn;k x;k gS tks lh[kus o le>us esa ijs”kkuh Create djrh gSa vkSj Language dks

tfVy cukrh gSaA

oSls “C” o “C++” dks mu yksxksa ds fy, fy[kk x;k Fkk tks igys ls gh is”ksoj Programmer Fks] ysfdu Java dks u, Programmers dks /;ku esa j[k dj Develop fd;k x;k gS] tks fd is”ksoj ugha gSa vkSj Computer dks cgqr xgjkbZ ls ugha tkurs cfYd ftUgsa Computer dk lkekU; Kku gh gSA pwafd Java esa Structure o Union ugha gSa blfy, Java ,d iw.kZ Object Oriented Programming Language gS] D;ksafd blesa tks Hkh dke djuk gksrk gS] mlds fy, Class Develop djuh iMrh gSA blls Program Codes dks uk dsoy Reuse fd;k tk ldrk gS cfYd Program dks Maintain djuk Hkh vU; Languages dh rqyuk esa dkQh ljy gksrk gSA

Functions “C” o “C++” esa lHkh Program Codes dks fdlh uk fdlh Function esa fy[kk tkrk gSA ;gka rd fd Main Program Hkh ,d Function main() esa gksrk gS tgka vko”;drkuqlkj vU; Functions dks Call djds viuk dke iwjk fd;k tkrk gSA ;s Functions Global j[ks tkrs gSa rkfd iwjs Program dk dksbZ Hkh vU; Function bUgsa Call dj lds vkSj Data ij Required Processing dj ldsA “C++” esa Hkh Functions gksrs gSa ftuds ek/;e ls Class ds Data dks Access fd;k tkrk gSA bu Functions dks gh Method dgk tkrk gSA “C++” Class ds Methods Java Class ds Methods ds leku gh gksrs gSaA fQj Hkh pwafd “C++” “C” tSlh Procedural Language dks Hkh Support djrk gS blfy, bls iwjh rjg ls Object Oriented Programming Language ugha dgk tk ldrk] cfYd bls Hybrid Language dgk tkrk gSA bl fLFkfr esa “C++” ds Class ds Methods o Class ds ckgj ds Functions nksuksa dk Mixture gksrk gS] blfy, dqN gn rd “C++” esa Confusion dh fLFkfr Hkh cuh jgrh gS ftlls dbZ ckj vthc rjg ds Bugs dk lkeuk djuk iMrk gSA Java esa dksbZ Function ugha gksrk gS] blfy, Java “C++” dh rqyuk Oriented Programming Language gSA Java Programmer dks bl gS fd Programmer vius lHkh Routines dks Class Methods ds :i Java dh bl ck/;rk ds dkj.k Programmer vius Codes dks Organize djds j[krk gSA

esa iwjh rjg ls Object ckr ds fy, ck/; djrh esa O;ofLFkr djds j[ksA vf/kd vPNs rjhds ls

Multiple Inheritance

Multiple Inheritance “C++” dh ,d ,slh O;oLFkk gS ftlesa ge dbZ Classes ls viuh vko”;drkuqlkj dqN&dqN Features dks ysdj ,d ubZ Class cuk ldrs gSaA ;kuh ge ,d Class dks dbZ Parent Class ls Derive dj ldrs gSaA gkykafd Multiple Inheritance okLro 33 Any Question or Suggestion, Just Discuss Here...

Java in Hindi esa dkQh Powerful gS] ysfdu dbZ Classes ls ,d Derive Class cukus o mls Maintain djus esa Programmer dks dkQh ijs”kkuh dk lkeuk djuk iMrk gSA Java Multiple Inheritance dks Support ugha djrk gSA “C++” dh bl Functionality dks ge Java esa Interfaces dk iz;ksx djds izkIr dj ldrs gSaA Java ds Interfaces Object Method Description Provide djrs gSa ysfdu buesa dksbZ Implementation ugha gksrk gSA

Strings “C” o “C++” esa Text Strings dks Handle djus ds fy, dksbZ Built – In Support ugha gSA String dks Handle djus ds fy, “C” o “C++” Programmers dks ,d Null Terminated Array dk iz;ksx djuk iMrk gSA Java esa Strings dks ,d First Class Object dh rjg Implement fd;k tkrk gS ;kuh] Strings Java Language dk eq[; fcUnq ;k Core gSA Java esa ge ,d Object ds :i esa String dks Implement djrs gSa] ftlls gesa dbZ Advantages izkIr gksrh gSA

goto Statement “C” o “C++” esa bl Statement dks vko”;drkuqlkj dkQh Use fd;k tkrk gSA ysfdu blds Use djus ij ftruh rjg dh ijs”kkfu;ka vkrh gSa] mUgsa r; djuk gh eqf”dy gSA goto Statement dk iz;ksx ;fn cMs Program esa fd;k tkrk gS] rks fdlh u, Programmer ds fy, ml Program dks le>uk ukeqefdu gks tkrk gSA ;s ,d Branching Statement gS] ysfdu Program esa ;s Statement Program Control dks dkQh Jump djokrk gS] ftlls Program dh Efficiency Hkh izHkkfor gksrh gSA Java esa bl Statement dks Support ugha fd;k x;k gSA Java us goto dks ,d Keyword ds :i esa ekU;rk nh gS ysfdu blds mi;ksx dks Support ugha fd;k gSA

Operator Overloading Operator Overloading dks Java esa Support ugha fd;k x;k gSA Operator Overloading “C++” dh ,d ,slh rduhd gS ftlls fdlh Hkh Primary Operator dks vko”;drkuqlkj nwljk vFkZ iznku dj fn;k tkrk gSA tSls + Operator dk iz;ksx nks Objects dks tksMus ds fy, fd;k tk ldrk gSA gkykafd Java esa bl dke dks Class esa fd;k tkrk gSA ysfdu Operator Overloading rduhd dks Java esa NksM fn;k x;k gSA Operator Overloading Programmer ds fy, ,d lqfo/kk gksrh gS] ysfdu blls ,d gh Operator dks ,d gh Program esa fofHkUu vFkZ iznku dj fn, tkus ls Program dks le>us esa Confusion gks tkus dh lEHkkouk jgrh gSA blfy, bl rduhd dks Java esa NksM fn;k x;k gSA Automatic Type Casting “C” o “C++” esa Automatic Type Casting gks ldrh gSA ;kuh ,d Integer izdkj ds Variable dks ;fn Float izdkj dk eku iznku djuk gks] rks “C” o “C++” dk Compiler Automatic Type Casting djds ,d Variable ds eku dks nwljs Variable ds eku esa Automatically Convert dj nsrk gSA ;g Automatic Type Casting dgykrh gSA tcfd Java esa bls Support ugha fd;k x;k gSA


Java in Hindi D;ksafd tc fdlh ,d Data Type ds Variable dks nwljs izdkj ds Data Type ds Variable dk eku iznku fd;k tkrk gS] rks Data ds eku dk Loss gks tkrk gSA tSls ;fn Integer izdkj ds Variable dks fdlh Float izdkj ds Variable dk eku iznku fd;k tk,] rks Integer izdkj ds Variable esa Float izdkj ds eku esa nleyo ds ckn dh la[;k Store ugha gksrh gSA ;kuh nleyo ds ckn dh la[;k dk Loss gks tkrk gSA blfy, Java esa bl Automatic Type Casting dks Support ugha fd;k x;k gSA Java esa ;fn fdlh Data ds eku dk fdlh Hkh izdkj dh izfØ;k ls Loss gksrk gS rks Java Automatic Type Casting ugha djrk gSA bldh Type Casting Programmer dks gh djuh iMrh gSA Variable Number of Arguments “C” o “C++” esa geus ns[kk gS fd ge printf() Function ;k Scanf() Function esa viuh vko”;drkuqlkj ,d ;k ,d ls vf/kd pkgs ftrus Hkh Arguments iznku dj ldrs gSaA ;fn gesa pkj Variable ds eku Output esa Print djus gksa rks ge printf() Function esa pkj Variable Argument ds :i esa Hkst ldrs gSa vkSj ;fn dsoy ,d gh Variable dk eku Print djuk gks rks dsoy ,d Argument Hkh printf() Function esa Hkst ldrs gSA gkykafd ;s ,d vPNk rjhdk gS ysfdu Java esa bls Support ugha fd;k x;k gSA D;ksafd Compiler ;s dHkh Check ugha dj ikrk gS fd mls ftl Argument ds eku dks Print djuk gS og mfpr Data Type dk gS ;k ughaA Command Line Argument Java Program esa ftl rjg ls Command Line ij Argument Pass fd, tkrs gSa os “C” o “C++” ds Program esa Pass fd, tkus okys Arguments dh rqyuk esa FkksMs vyx gksrs gSaA “C” o “C++” esa System main() Function dks nks Arguments Pass djrk gSA igyk Argument argc vkSj nwljk Argument argv gksrk gSA igyk Argument argc ;s Specify djrk gS fd nwljs Argument argv esa fdrus Arguments gSaA nwljk Argument argv ,d Array of Characters dk Pointer gksrk gSA blh Argument esa Command Prompt ij fn, tkus okys Actual Arguments gksrs gSaA Java esa System Command Line ls dsoy ,d gh Argument args Java Program esa Pass djrk gSA ;s ,d Strings dk Array gksrk gS ftlesa Command Line Arguments gksrs

gSaA

“C” o “C++” esa Command Line Arguments ,d Program esa Pass gksrs gSaA bl Argument esa ml Program dk uke Hkh gksrk gS ftlesa Arguments dks Pass djuk gksrk gSA ;s uke Command Line ij lcls igys First Argument ds :i esa fy[kk tkrk gSA Java esa ge igys ls gh ml Program dk uke tkurs gksrs gSa ftlesa gesa Argument Hkstuk gksrk gSA ;s uke gesa”kk ml Program ds Class dk uke gh gksrk gS] blfy, Command Prompt ij gesa dsoy Argument gh Pass djuk gksrk gSA


Java in Hindi Programming – The Basic Concept

Computer Programming le>us ls igys gesa ;s le>uk gksrk gS fd Computer D;k dke djrk gS vkSj dSls dke djrk gSA dEI;qVj dk eq[; dke Data dk Management djuk gksrk gSA gekjs vkl&ikl tks Hkh phtsa gesa fn[kkbZ nsrh gSa os lHkh ,d Object Oriented Programming Language ds fy, Objects gSaA

gj Objects ds dqN Attributes gksrs gSa] ftuls fdlh Particular Object dh igpku gksrh gSA bl Attribute esa Numerical ;k Non–Numerical fdlh uk fdlh izdkj dk eku iznku fd;k tk ldrk gSA ;s eku gh Computer dk og Data gksrk gS] ftls Computer Manage djrk gSA ;fn fcYdqy gh ljy “kCnksa esa dgsa rks dksbZ eku ;k ekuksa dk lewg Computer ds fy, Data gksrk gSA ;s eku nks rjg ds gks ldrs gSa % Numerical ;k Non-Numerical, Computer esa ge bUgha Data dks Store djrs gSa] Process djrs gSa vkSj fdlh uk fdlh izdkj dh Information Generate djrs gSaA Computer dsoy Electrical Signals ;k e”khuh Hkk’kk dks le>rk gSA ;s e”khuh Hkk’kk ck;ujh :i esa gksrh gS tgka fdlh Signal ds gksus dks 1 o uk gksus dks 0 ls iznf”kZr fd;k tkrk gSA ;fn ge gekjh fdlh ckr dks Binary Format esa Computer esa Feed dj ldsa] rks Computer gekjh ckr dks le> ldrk gSA Computer Hkk’kk og Hkk’kk gksrh gS] ftls Computer le> ldrk gSA gj Computer Hkk’kk dk ,d Software gksrk gS] ftls Compiler ;k Interpreter dgrs gSaA ;s Software gekjh ckr dks Computer ds le>us ;ksX; e”khuh Hkk’kk ;k Binary Format esa Convert djrk gSA Computer dks dksbZ ckr le>kus ds fy, mls ,d fuf”pr Øe esa lwpuk,a nsuh gksrh gSa] ftUgsa Instructions dgk tkrk gSA Computer bu nh xbZ Instructions ds vuqlkj dke djrk gS vkSj gekjh bPNkuqlkj gesa ifj.kke iznku djrk gSA Instructions ds bl lewg dks gh Program dgk

tkrk gSA

Computer esa gj Electrical Signal ;k mlds lewg dks Store djds j[kus dh lqfo/kk gksrh gSA bu Electrical Signals ds lewg dks File dgrs gSaA Computer esa tks Hkh dqN gksrk gS og File ds :i esa gksrk gSA Computer esa nks rjg dh File gksrh gSA igyh og File gksrh gS ftlesa ge gekjs egRoiw.kZ Data Store djds j[krs gSaA bls Data File dgk tkrk gSA

nwljh File og File gksrh gS] ftlesa Computer ds fy;s os Instructions gksrh gSa] tks Computer dks crkrh gSa fd mls fdlh Data ij fdl izdkj ls Processing djds Result Generate djuk gSA bl nwljh izdkj dh File dks Program File dgk tkrk gSA ge fofHkUu izdkj dh Computer Languages esa Program Files gh Create djrs gSaA tc cgqr lkjh Program Files fey dj fdlh leL;k dk lek/kku izkIr djokrh gSa] rks mu Program Files ds lewg dks Software dgk tkrk gSA Computer Software eq[;r;k nks izdkj ds gksrs gSa%


Java in Hindi System Software: ;s Software mu izksxzkeksa dk ,d lewg gksrk gSa tks dEI;wVj dh Performance dks Control djrk gSA ;kuh Computer ij fdl rjg ls ,d izksxzke ju gksxk vkSj fdl rjg ls izksxzke Output nsxkA fdl rjg Hard Disk ij Files Save gksaxh] fdl rjg iqu% izkIr gksaxh] vkfnA Windows, Unix, Linux, vkfn System Software ds mnkgj.k gSaA Application Software: ;s Software izksxzkejksa }kjk fy[ks tkrs gSa o ;s Software fdlh [kkl izdkj dh leL;k dk lek/kku izkIr djus ds fy;s gksrs gSaA tSls Tally, MS–Office vkfn Application Software ds mnkgj.k gSaA

Computer Architecture Computer ls viuk eupkgk dke djokus ds fy,] lcls igys gesa Computer ds Architecture dks le>uk gksxkA Computer ds Architecture dks le>s fcuk] ge Computer Programming dks Bhd ls ugha le> ldrsA Computer System ds eq[;&eq[; rhu Hkkx gksrs gSa&

I/O Devices os Devices ftuls Computer esa Data Input fd;k tkrk gS vkSj Computer ls Data Output esa izkIr fd;k tkrk gS] I/O Devices dgykrh gSaA Keyboard ,d Standard Input Device gS vkSj Monitor ,d Standard Output Device gSA

Center Processing unit (CPU) ;g ,d Microprocessor Chip gksrk gSA bls Computer dk fnekx Hkh dgk tkrk gS D;ksafd Computer esa tks Hkh dke gksrk gS] mu lHkh dkeksa dks ;k rks CPU djrk gS ;k Computer ds vU; Devices ls mu dkeksa dks djokrk gSA bldk eq[; dke fofHkUu izdkj ds Programs dks Execute djuk gksrk gSA bl CPU esa Hkh fuEu foHkkx gksrs gSa tks vyx&vyx dke djrs gSa&


Java in Hindi Control Unit bl Unit dk eq[; dke lkjs Computer dks Control djuk gksrk gSA CPU dk ;s Hkkx Computer dh vkarfjd izfØ;kvksa dk lapkyu djrk gSA ;g Input/Output fØ;kvksa dks Control djrk gS] lkFk gh ALU o Memory ds chp Data ds vknku&iznku dks funsZf”kr djrk gSA ;g Program dks Execute djus ds fy, Program ds Instructions dks Memory ls izkIr djrk gS vkSj bu Instructions dks Electrical Signals esa Convert djds mfpr Devices rd igqapkrk gS] ftlls Data ij Processing gks ldsA Control Unit ALU dks crkrk gS fd Processing ds fy, Data Memory esa dgka ij fLFkr gSa] Data ij D;k izfØ;k djuh gS vkSj Processing ds ckn Data dks okil Memory esa dgka ij Store djuk gSA Arithmetic Logic Unit (ALU) CPU ds bl Hkkx esa lHkh izdkj dh vadxf.krh; o rkfdZd izfØ;k,a gksrh gSaA bl Hkkx esa ,slk Electronic Circuit gksrk gS tks Binary Arithmetic dh x.kuk,a djrk gSA ALU Control Unit ls funsZ”k ;k ekxZn”kZu ysrk gS] Memory ls Data izkIr djrk gS vkSj ifj.kke dks ;k Processed Data dks okil Memory esa gh Store djrk gSA Registers

Microprocessor esa dqN ,slh Memory gksrh gS tks FkksMs le; ds fy, Data dks Store dj ldrh gSA bUgsa Registers dgk tkrk gSA Control Unit ds funsZ”kkuqlkj tks Hkh Program Instructions o Data Memory ls vkrs gSa os ALU esa Calculation ds fy, bUgha Registers esa Store jgrs gSaA ALU esa Processing ds ckn okil ;s Data Memory esa Store gks tkrs gSaA

Memory Memory Computer dh Working Storage ;k dk;Zdkjh eseksjh gksrh gSA ;g Computer dk lcls egRoiw.kZ Hkkx gksrk gSA bls RAM dgrs gSaA blh esa Process gksus okys Data vkSj Data ij Processing djus ds fy[ks x, Program Instructions gksrs gSa] ftUgsa Control Unit ALU esa Processing ds fy, Registers esa Hkstrk gSA Processing ds ckn tks lwpuk,a ;k Processed Data Generate gksrs gSa] os Hkh Memory esa gh vkdj Store gksrs gSaA Memory esa Data dks laxzg djus ds fy, dbZ Storage Locations gksrh gSaA gj Storage Location ,d Byte dh gksrh gS vkSj gj Storage Location dk ,d iw.kkZad Number gksrk gS] ftls ml Memory Location dk Address dgrs gSaA gj Storage Location dh igpku mlds Address ls gksrh gSA 1 Byte dh RAM esa ,d gh Character Store gks ldrk gS vkSj blesa flQZ ,d gh Storage Location gks ldrh gSA

blh rjg 1 KB dh RAM esa 1024 Storage Locations gks ldrh gSa vkSj blesa 1024 v{kj Store gks ldrs gSaA tks Memory ftrus Byte dh gksrh gS mlesa mrus gh Characters Store gks ldrs gSa vkSj mlesa mruh gh Storage Locations gks ldrh gSaA


Java in Hindi ftl rjg ls fdlh “kgj esa us dh dksf”k”k djrs gSaA tc ge Keyboard (Input Device) ij dksbZ Key Press djrs gSa] rks CPU dk Control Unit Active gks tkrk gS vkSj Input gks jgs Character dks Memory esa fdlh Storage Location ij Store dj nsrk gSA ekuk ge Keyboard ls ,d vad 6 Input djrs gSa] rks CPU dk Control Unit bl eku dks Memory dh fdlh Storage Location ij Store dj nsrk gSA vc ge + dk fpUg Keyboard ls Press djrs gSaA Control Unit mls Hkh Memory dh fdlh Storage Cell esa Store dj nsrk gSA vc ge 4 Input djrs gSaA Control Unit bls Hkh Memory esa Store djrk gSA ekuk fd ;s rhuksa eku fuEukuqlkj Memory dh fofHkUu Storage locations ij Save gks jgh gSa &

vc ;fn Input fd, x, nksuksa vadksa dks tksMuk gks rks Control Unit Input fd, x, igys eku Storage Cell 1001 ls mBkrk gS vkSj mls Binary Format esa Convert djds CPU Registers esa Hkst nsrk gSA fQj bl vad ij Processing djus ds fy, Control Unit + Memory Location 1003 ls mBkrk gS vkSj CPU dks bl vad dks tksMus dh izfØ;k djus Instruction nsrk gSA

dks ds dks dh

fQj Control Unit nwljs eku 4 dks Binary Format esa Convert djds CPU ds Register esa Hkst nsrk gS vkSj ALU dks bu nksuksa vadks dks tksMus dh lwpuk nsrk gSA ALU Registers ls bu Data dks izkIr djds mUgsa tksMrk gS vkSj tksMs x, eku dks CPU ds Registers esa Store dj nsrk gSA ;gka ls okil Control Unit Registers esa Stored eku dks Memory esa Storage Cell 1009 o 1010 ij Store dj nsrk gSA bl rjg ls nks la[;kvksa dks tksMus dh izfØ;k iwjh gksrh gSA Computer ,d Digital Machine gSA Computer rHkh dksbZ dke dj ldrk gS tc mls fdlh dke dks djus ds fy, Program fd;k x;k gksA Programming nks rjg dh gksrh gSA igyh Programming og gksrh gS tks fdlh Computer dks dke djus yk;d voLFkk esa ykus ds fy, dh tkrh gSA bl Programming dks Hkh nks Hkkxksa esa ckaVk tk ldrk gS%

Hardware Programming bl Programming ds vUrxZr Computer ds Hardware ;kuh Computer ds Motherboard ij yxk, x, fofHkUu izdkj ds Chips o Computer ls tqMs gq, vU; fofHkUu izdkj ds Peripherals tSls fd Keyboard, Mouse, Speaker, Monitor, Hard Disk, Floppy Disk, 39 Any Question or Suggestion, Just Discuss Here...

Java in Hindi CD Drive vkfn dks Check djus o Control djus ds fy, gj Mother Board ij ,d BIOS Chip yxkbZ tkrh gSA bl BIOS Chip dk eq[; dke Computer dks ON djrs gh fofHkUu izdkj ds Devices dks Check djuk gksrk gSA

;fn Computer ds lkFk tqMh gqbZ dksbZ Device
Software Programming Computer dks dke djus yk;d voLFkk esa ykus ds fy, ftl Software dks cuk;k tkrk gS] mls Operating System Software dgk tkrk gSA BIOS Chip dk dke iwjk gksus ds ckn Computer dk iwjk Control Operating System Software ds ikl vk tkrk gSA Computer ds ikl BIOS ls Controlling vkus ds ckn lcls igys Memory esa Load gksus okyk Software Operating System Software gh gksrk gSA bls Master Software ;k Operating System Software Hkh dgrs gSaA vkt fofHkUu izdkj ds Operating System Software cu pqds gSa tSls DOS, Windows, OS/2, WRAP, Unix, Linux vkfnA bu lHkh Software dk eq[; dke Computer dks Boot djds User ds dke djus ;ksX; voLFkk esa ykuk gksrk gSA nwljh Programming og Programming gksrh gS] ftlls Computer gekjh ckr dks le>rk gS vkSj gekjh bPNkuqlkj dke djds gesa ifj.kke iznku djrk gSA bUgsa Application Software dgk tkrk gSA ge fdlh Hkh Operating System ds fy, fdlh Hkh Hkk’kk esa tc dksbZ Program fy[krs gSa] rks okLro esa ge Application Software gh fy[k jgs gksrs gSaA Application Software dk eq[; dke fdlh fo”ks’k leL;k dk lek/kku iznku djuk gksrk gSA MS-Office, Corel-Draw, PageMaker, PhotoShop vkfn Application Software ds mnkgj.k gSa] tks gesa fdlh fo”ks’k leL;k dk lek/kku iznku djrs gSaA tSls ;fn gesa Photo Editing ls lEcaf/kr dksbZ dke djuk gks rks ge PhotoShop tSls fdlh Application Software

dks mi;ksx esa ysrs gSaA

Language Hkk’kk] nks O;fDr;ksa ds chp laokn] Hkkoukvksa ;k fopkjksa ds vknku&iznku dk ek/;e iznku djrh gSA ge yksxksa rd vius fopkj igqapk ldsa o vU; yksxkas ds fopkjksa dk ykHk izkIr dj ldsa] blds fy;s t:jh gS fd laokn LFkkfir djus okys nksuksa O;fDr;ksa ds chp laokn dk ek/;e leku gksA ;gh laokn dk ek/;e Hkk’kk dgykrh gSA vyx&vyx LFkku] jkT;] ns”k] ifjfLFkfr;ksa ds vuqlkj Hkk’kk Hkh cnyrh jgrh gSa] Yksfdu lHkh Hkk’kkvksa dk edln lans'kksa ;k lwpukvkas dk vknku iznku djuk gh gksrk gSA


Java in Hindi Bhd blh rjg dEI;wVj dh Hkh viuh dbZ Hkk’kk,a gS] tks t:jr o mi;ksx ds vuqlkj fodflr dh xbZ gSA ge tkurs gSa] fd dEI;wVj ,d bysDVªkWfud e”khu ek= gSA ;s ge lthoksa dh rjg lksap fopkj ugha dj ldrk gS vkSj uk gh gekjh rjg budh viuh dksbZ Hkk’kk gS] ftlls ge buls lEca/k cuk dj lwpukvksa dk ysu&nsu dj ldsaA blfy;s dEI;wVj dks mi;ksx esa ysus ds fy;s ,d ,slh Hkk’kk dh t:jr gksrh gS] ftlls ge gekjh Hkk’kk esa dEI;wVj dks lwpuk,a nsa o dEI;wVj mls mldh e”khuh Hkk’kk esa le>s vkSj gekjh pkgh xbZ lwpuk ;k ifj.kke dks gesa gekjh Hkk’kk esa ns rkfd ge mls gekjh Hkk’kk esa le> ldsaA Java ,d ,slh gh Hkk’kk gSA ;s ,d High Level Language gSA bl Language esa ge lkekU; English ds “kCnksa esa Code fy[krs gSaA bu Codes dks Java dk ,d Software Program ftls Compiler dgrs gSa] ml Hkk’kk esa Convert djrk gS] ftls Computer le> ldrk gSA bl Software dh enn ls Compute gekjs fy[ks x, Codes ds vuqlkj dke djrk gS vkSj gesa og ifj.kke iznku djrk gS] tks ge Computer ls pkgrs gSaA Java dk Program fy[kus ds fy, ,d Simple Word Processor dh t:jr gksrh gSA Windows ds lkFk vkus okys Notepad dks ge Java dk Program fy[kus ds fy, Use dj ldrs gSaA Java esa gj Program dks ,d Class ds :i esa fy[kk tkrk gSA Program fy[kus ds ckn Source File dks .Java Extension ds lkFk Save fd;k tkrk gSA Java esa nks rjg ds Programs lcls T;knk fy[ks tkrs gSaA tc ge Java Application fy[krs gSa rks ml Application esa gesa”kk ,d main() Method gksrk gSA Java ,d Case Sensitive Language gS blfy, Capital Letters esa fy[kk x;k uke o Small Letters esa fy[kk x;k uke

nksuksa uke vyx&vyx gksrs gSaA

Java Compiler (javac)

Java Compiler (Javac) Java Developer’s Kit dk ,d Component gS] ftldk iz;ksx Java dh Source Code File dks Bytecodes Executable File esa Convert djus ds fy, fd;k tkrk gS] rkfd og File Java Runtime Environment (JRE) System esa Run gks ldsA Java dh Source Code File dk Extension .java gksrk gSA Java dh Source Code File ,d Standard ASCII Text File gksrh gSA ;s Java ds Compiler dk dke gksrk gS fd og Java Source Code File dks Process djs vkSj Executable Java Bytecodes Class File Create djsA Executable Bytecodes Class File dk Extension .class gksrk gS vkSj ;s viuh Useable Form esa Java Class dks Represent

djrs gSaA

Java Compiler gekjh Source File dh gj Class ds fy, ,d .Class File Generate djrk gSA rduhdh :i ls ge ,d gh Source File esa ,d ls vf/kd Class Define dj ldrs gSa ysfdu Compiler ,d gh Source File esa Define dh xbZ ,d ls vf/kd Classes ds fy, Hkh vyx&vyx .class File Create djrk gSA Java Compilers bl ckr ds fy, ftEesnkj gksrs gSa fd ,d Java Source File ls Java Executable Bytecodes File fdl izdkj ls Generate dh tk, tks fd Java Runtime System esa Run gks ldsa vkSj Java Virtual Machine, tks fd Java Runtime System dk


Java in Hindi ,d fgLlk gS] bl ckr ds fy, ftEesnkj gksrk gS] fd Bytecodes dks fdl izdkj ls Interpret fd;k tk,A Java Compiler ,d Command Line Tool gSA bldk eryc ;s gqvk fd bUgsa DOS Prompt ij gh Execute fd;k tk ldrk gSA budks Use djus dk Syntax fuEukuqlkj gksrk gS% Command Prompt > javac Options Filename

bl Command esa Filename Argument ml Java Source Code File dk uke gksrk gS ftls Compile djuk gSA bl File esa ftruh Hkh Classes Define dh xbZ gksrh gSa] mu lHkh dh Bytecodes okyh .class File curh gSA ;s Compiler mu lHkh Classes dks Bytecodes Class File esa Convert dj nsrk gS tks ,d nwljs ij Depend gksrh gSaA ;kuh ekuyks fd ,d File X.Java gS vkSj bl File esa ,d nwljh File ftldk uke B.Java gS] dh Class dks Derive fd;k x;k gSA rks bl fLFkfr esa ge ;fn B.Java dks Compile djrs gSa rks Compiler X.Java dh Hkh Compiling djsxk vkSj nksuksa Qkbyksa ds lHkh Classes dh Bytecodes (.Class) File Generate djsxkA

Java Interpreter (java)

Java Runtime Interpreter (Java) Hkh Java Developer’s Kit dk ,d Component gS ftldk iz;ksx Executable Java Bytecodes Classes dks Run djus ds fy, fd;k tkrk gSA Java Interpreter ,d rjhdk iznku djrk gS ftlls Java ds Programs dks fdlh Web Browser ds fcuk Execute fd;k tk ldrk gSA Java Compiler ftl Class Format dh Executable Bytecodes File dks Generate djrk gS] ml Bytecodes File dks Java Interpreter }kjk Execute fd;k tkrk gSA

fdlh Java Applet o Java Application Program esa bruk gh vUrj gS fd Applet fdlh uk fdlh Java Enabled Web Browser esa Run gksrs gSa] tcfd Application dk Lo;a dk Window gksrk gSA fdlh Compile fd, x, Java Source File dh Bytecodes (.Class) File dks ge fuEukuqlkj Syntax }kjk Command Prompt ij Run dj ldrs gSa& Command Prompt>Java ClassName Arguments

;gka ClassName ml Class File dks Specify djrk gS] ftls Execute djuk gSA ;fn ;s Class File fdlh Package esa gks rks gesa Class File dk iwjk uke nsuk gksrk gSA tSls ekuyks fd dksbZ Hello.class uke dh Class File India uke ds Package esa gS] rks gesa bl File dks Run djus ds fy, fuEukuqlkj Command fy[kuk gksxk% Command Prompt>Java India.Hello

tc Java Interpreter fdlh Class dks Execute djrk gS rks og okLro esa ml Class ds main() Method dks Execute dj jgk gksrk gSA main() Method esa ge dqN Arguments Hkh ns ldrs gSa ftudk iz;ksx main() Method ds Execution dks Control djus ds fy, fd;k tkrk gSA


Java in Hindi Structure of Java Programs

fdlh tkok ds Program esa ge vko”;drkuqlkj ,d ls vf/kd Classes dks Define dj ldrs gSaA ysfdu fQj Hkh ge ,d Program esa fdlh ,d Class esa gh main() Method dks Define dj ldrs gSaA fofHkUu Classes esa fofHkUu izdkj ds Data vkSj mu Data ij Perform gksus okys Operations dks Define fd;k tkrk gSA tkok dk Program cukus ds fy, ge lcls igys fofHkUu izdkj dh Classes cukrs gSa vkSj fQj mu lHkh Classes dks Combine dj ysrs gSaA ,d tkok Program ds fofHkUu foHkkxksa dks ge fuEukuqlkj n”kkZ ldrs gSa % Documentation Section Package Statements Import Statements Interface Statements Class Definitions { Data Members Methods Main Method Class { Main Method Definitions }

Documentation Section fdlh Hkh Program ds bl Section esa gesa Program ls lEcaf/kr Descriptions nsus gksrs gSaA tSls fd Author dk uke, Program Creation dh Date] Program Create djus dk dkj.k] Program dh mi;ksfxrk vkfn ls lEcaf/kr ckrsa gesa Comment ds :i esa Documentation Section esa fy[kuh gksrh gSaA gkykafd ;s ,d Optional Section gS] fQj Hkh Program dks Readable cukus ds fy, gesa gj Program dks Well Documented djuk pkfg,A ;gka gesa ;s crkuk pkfg, fd geus Program esa fdu Classes dks Use fd;k gS vkSj fdl dkj.k ls Use fd;k gSA lkFk gh Program ds Algorithm ;kuh Flow dks Hkh lkjka”k :i esa Describe djus dh dksf”k”k djuh pkfg,A lkekU;r;k Documentation dks /** . . . */ Format esa fy[kuk pkfg,A bl rjg ls Comment djus ij ge Documentation dh ,d File JDK Tools ds mi;ksx }kjk Generate dj ldrs gSaA

Package Statements Package Statement fdlh Hkh tkok Program dk igyk Statement gksrk gSA ;s Statement ,d Package dk uke Declare djrk gS vkSj tkok Program dks crkrk gS fd Program esa Use gksus okyh Classes bu Packages esa Defined dh xbZ gSaA fdlh Package dks ge fuEukuqlkj tkok ds Source Program esa Use dj ldrs gSa %


Java in Hindi package StudentInformation;

;s Statement StudentInformation uke ds Package dks ml Program ;k Source File esa Include dj ysxk] ftlesa ;s Statement fy[kk x;k gksxkA Import Statements fdlh Package Statement ds ckn tks vxyk Statement gks ldrk gS og import Statements gksrk gSA igys ls cuh gqbZ fdlh Class dks tkok ds Source Program esa Include djus ds fy, gesa tkok ds import Keyword ds lkFk ml Class dk uke fy[kuk gksrk gS] ftls vius Program esa Use djuk gksrk gSA ;s dke ge fuEukuqlkj Statement }kjk dj ldrs gSa % import StudentInformation.testMarks;

;s Statement tkok Interpreter dks testMarks uke dh Class dks Source File esa Include djus dk Message nsrk gS] tks fd StudentInformation uke ds Package esa miyC/k gS vkSj bl package dk ,d fgLlk gSA

Interface Statements Interface ,d Class ds leku gh gksrk gS ysfdu blesa Methods ds Declarations dk ,d Group gksrk gSA ;s Hkh ,d Optional Statement gS vkSj bldk iz;ksx ge rHkh djrs gSa tc gesa vius Program esa Multiple Inheritance dh lqfo/kk izkIr djuh gksrh gSA bl fo’k; esa ge vkxs foLrkj ls i
Main Method Class tkok ds gj Application Program esa gesa ,d Main() Method dh t:jr gksrh gS] ftldks tkok Compiler lcls igys Execute djrk gSA ;s fdlh Hkh tkok Application Program dk ,d cgqr gh t:jh fgLlk gSA fdlh Simple tkok Program esa dsoy ;s ,d Method Hkh gks ldrk gSA Main Method fofHkUu izdkj dh Classes ds Objects Create djrk gS vkSj muds chp esa Communication dks Establish djrk gSA Main Method ds vUr esa igqapus ij Program Terminate gks tkrk gS vkSj Program Control iqu% Operating System dks Transfer gks tkrk

gSA

Definition – The Applet and Application

tkok esa ge nks rjg ds Programs Develop dj ldrs gSaA igys Program os Program gksrs gSa tks fdlh ,d Computer ij Execute gksrs gSa vkSj fdlh leL;k dk lek/kku iznku djrs gSaA ;s Programs ftl Computer ij Store gksrs gSa mlh Computer ij Run gksrs gSa vkSj ml Computer ds Resources dks Use djrs gSaA


Java in Hindi bl izdkj ds Programs dks Application Programs dgrs gSaA tcfd tkok esa ftl nwljs izdkj ds Program dks Develop fd;k tk ldrk gS] mu Programs dks Run gksus ds fy, tkok Platform Enabled Web Browser dh t:jr gksrh gSA ;kuh ;s os Programs gksrs gSa tks fdlh uk fdlh Web Page esa Run gksrs gSa vkSj bUgsa mi;ksx esa ysus ds fy, gesa Web Browser dh t:jr gksrh gSA tkok esa Develop fd, tkus okys bl nwljs izdkj ds Programs dks Java Applets dgrs gSaA

Java - Applications tkok bruk l{ke gS fd ge blesa Professional Applications Develop dj ldrs gSaA ge blesa fofHkUu izdkj ds Window Based Applications cuk ldrs gSa vkSj mUgsa lQyrk iwoZd mi;ksx esa ys ldrs gSaA ysfdu pwafd tkok ,d Interpreted Language gS] blfy, blds Programs dh Speed “C” o “C++” Languages esa Develop fd, x, Applications dh rqyuk esa de gksrh gSA blfy, lkekU;r;k tkok Based Applications rHkh cuk, tkrs gSa] tc Application Distributed gks o Network ij Execute gksrk gksA D;ksafd tkok Internet ds fy, ,d cgqr gh vPNh o Powerful Programming Language blfy, blesa Desktop Applications ugha cuk, tkrs gSaA D;ksafd Desktop Applications fy, Visual Basic, “C” o “C++” Programming Languages dkQh vPNh Languages blfy, tkok dk iz;ksx lkekU;r;k Web Pages ds Applets cukus ds fy, fd;k tkrk ftlds ckjs esa ge vkxs foLrkj ls le>saxsA

gS] ds gSa] gS]

First Application in Java fdlh Hkh Language esa Programming lh[kus ds fy, ge lcls igys Hello World Program ls “kq:vkr djrs gSaA ;s Program dqN ugha djrk gS] dsoy Screen ij “Hello World” Message Print djrk gS] ysfdu bl Program ds }kjk ge Language ds Program dh Basic phtksa dks Clear djrs gSaA “Hello World” Application

lcls igys uhps fy[ks x, Program dks Notepad esa Type djsa% "Hello World" Application Program class HelloWorld { public static void main(String[] args) { System.out.println("Hello World"); } }

//Display this String


Java in Hindi Notepad esa bl Coding dks Type djus ds ckn File Menu ls Save Option dks Select djsaA fuEukuqlkj ,d Save As Dialog Box Display gksxk%

bl Dialog Box esa Save as type Drop Down List esa All Files dks Select djsa] D;ksafd ;gka gesa”kk Default :i ls Text Documents (*.txt) Option Selected jgrk gSA vc Save in Drop Down List ls ml Folder dks Select djsa] tgka ij Java dh File dks Save djuk gS vkSj File name Text Box esa File dk ogh uke fy[ksa tks uke Source File esa ml Class dk gS ftlesa main() Method fy[kk x;k gSA pwafd gekjs bl Example dh Source File esa main() Method dks HelloWorld Class esa fy[kk x;k gS blfy, gekjh Source File dk uke gesa HelloWorld gh nsuk gksxk lkFk gh gekjh Source File, Java dh ,d Program File gS] blfy, bls .java Extension ds lkFk Save djuk gksxkA bl izdkj ls gekjh bl File dk uke HelloWorld.java gksxkA ,slk ugha gS fd ge bl Source File dk ogh uke nsa tks geus Source File esa Class dk uke fn;k gSA ge File dk uke dqN Hkh ns ldrs gSa] ysfdu tc File dks Compile fd;k tkrk gS] rks ,d Class File curh gSA bl Class File dk uke fcYdqy ogh gksrk gS] tks ml Source File dh ml Class dk uke gksrk gS] ftlesa main() Method fy[kk x;k gksrk gSA blfy, fdlh Hkh rjg ds Confusion ;k ijs”kkuh ls cpus ds fy, Bhd ;gh jgrk gS] fd ge gesa”kk gekjh Source File dks Hkh mlh uke ls Save djsa] ftl uke ls ge og Class cukrs gSa] ftlesa main() Function gksrk gSA

Compiling Java Source File Source File Create djus ds ckn vc gesa bl Source File dks Compile djuk gksrk gS] rkfd ;s File Byte Codes esa Convert gks ldsA Compile djus ds fy, gesa Command Prompt ;k DOS Prompt ij tkuk gksrk gS vkSj fuEukuqlkj Command fy[kus gksrs gSa& Command Prompt \>cd\ C:\>path=C:\jdk\bin\

( Press Enter ) ( Press Enter )


Java in Hindi ge ;s eku jgs gSa fd tc Java dks Install fd;k tkrk gS rc Java dk 7th Version C: Drive ij jdk uke ds Folder esa Install gksrk gSA ;gka igys Command ls ge Root Directory ;kuh C: Drive ij vk tkrs gSa vkSj nwljk Statement Path Statement gSA ge fdlh QkbZy dks ogha ls Run dj ldrs gSa] tgka og File j[kh gqbZ gSA ysfdu DOS ds Path Command dh ;s fo”ks’krk gS fd ge fdlh File dks ogka ls Directly Run dj ldrs gSa] tgka dk Path ge Command Prompt ij Path Statement }kjk fy[k nsrs gSaA ge tkurs gSa fd Java ds Bin uke ds Folder esa gh Java ds lHkh t:jh Tools gksrs gSaA blfy, ge pkgrs gSa fd ge dgha ls Hkh Java ds Commands dks Execute dj ldsa vkSj ge ,slk rHkh dj ldrs gSa tc Computer dks igys gh ;s crk;k tk, fd mls Command Prompt ij fn, tkus okys fofHkUu Command dks dgka ij [kkstuk gSA pwafd ge pkgrs gSa fd ge fdlh Hkh LFkku ij Java dk tks Hkh Command fy[ksa] og Execute gks] rks gesa path=C:\jdk\bin\ fy[kuk gksrk gSA ;s Path Set fd, fcuk vkxs fy[ks x, dksbZ Command ugha pysaxsA blfy, lcls igys blh Command dks fy[k dj Path Set fd;k x;k gSA ge ftruh ckj Hkh Command Prompt ij vkrs gSa] gesa ;s Path Set djuk iMrk gSA ysfdu ;fn gesa gesa”kk ds fy, bl Path dks Permanently Set djuk gks] rks Command Prompt Open djds ge fuEu Command Fire dj ldrs gSa% CommandPrompt>setx PATH "c:\jdk\bin"

;s Commend Fire djrs gh gekjk Path, Windows Operating System dh Registry esa Add gks tkrk gSA ifj.kkeLo:i vc ge tc Hkh dHkh Command Prompt Open djrs gSa] gesa gekjs Path dks fQj ls Set djus dh t:jr ugha gksrhA Path Set djus ds ckn gesa ml Folder esa tkuk gksrk gS] tgka geus gekjh Source File dks Save dh gSA ekuyks fd geus gekjh Source File dks C: Drive esa Java uke dk ,d Folder cuk dj mlesa Save dh gS] rks ge fuEu Command }kjk vius Java Folder rd tkrs gSa& C:\>cd java C:\Java>

(Press Enter )

vc gesa HelloWorld.Java dks fuEukuqlkj Command fy[k dj Compile djuk gksxk& C:\Java>javac HelloWorld.Java

( Press Enter )

;fn Source File esa fdlh izdkj dh Error uk gks] rks Java dh File Compile gks tk,xhA tc Java dh File Compile gks tkrh gS] rc Java dh File dh ,d Class File curh gS] ftldk uke ogh gksrk gS tks gekjh Source File dk gksrk gS] ysfdu ml File dk Extension .class gksrk gSA ;s Class File Java dh Bytecodes File gksrh gS] tks fd Platform Independent gksrh gS vkSj fdlh Hkh Java Runtime Environment esa Interpret gksrh gSA


Java in Hindi Running Java Application tc Source File Bhd ls fcuk fdlh Error ds Compile gks tkrh gS] rc mldh ,d Class File curh gSA ;s Class File gh Java Runtime Environment esa Run gksrh gSA vc HelloWorld Application dks Run djus ds fy, gesa Command Prompt ij fuEu Command fy[kuk gksrk gS& C:\Java>java HelloWorld

( Press Enter )

vc gesa File dk Extension Use djus dh t:jr ugha gksrh gSA tkok dk ;s Interpreter lgh File dks Lo;a gh Run djrk gS vkSj gekjs Screen ij “Hello World” Display gksrk gSA ;gka ;s ckr /;ku j[kus okyh gksrh gS fd Source File dk uke ge pkgs tSlk Hkh nsa ysfdu File dks Run djrs le; gesa ogh uke nsuk iMrk gS] tks uke Class dk gksrk gS vkSj Bhd mlh rjg ls Class dk uke fy[kuk iMrk gS] ftl rjg ls Source File esa geus Class dk uke fy[kk gSA ;fn ge uke fy[kus esa tjk lh Hkh Mistake djrs gSa] rks gesa fuEukuqlkj Error Message izkIr gksrk gS& C:\JAVA>java helloworld Exception in thread "main" java.lang.NoClassDefFoundError: helloworld (wrong name: HelloWorld)

Anatomy of Java Application geus Java esa ,d NksVk lk Program Develop fd;k vkSj mls Compile djds Run Hkh dj fy;kA vc ge bldh cukoV o blds dke djus ds rjhds dks le>rs gSaA lcls igyh ckr rks ;gh gS fd Java Application Standalone Java Programs gksrs gSaA bUgsa Java Applets dh rjg fdlh Java Enabled Web Browser dh t:jr ugha gksrh gSA Comments in Java Java esa Comments nsus ds fy, rhu rjhdksa dk iz;ksx fd;k tk ldrk gSA rhuksa rjhdksa ls fuEukuqlkj Comment fn;k tk ldrk gS & /* This is a Comment in Java which Java Compiler Ignores. */

bl /* */ ds chp fy[ks x, Comments dks Java dk Compiler iwjh rjg ls Ignore dj nsrk gSA ;kuh buds chp fy[ks x, fdlh Hkh Word dks Compiler Check ugha djrk gS uk gh Compile djrk gSA ;s Comments ,d Programmer vius Program ds chp&chp esa nsrk jgrk gS] rkfd mls mlds Program dk Flow irk jgsA /** Documentation */ bl Comment dks Documentation Comment ;k Doc Comment dgk tkrk gSA tc ge gekjh fdlh Class File dk Documentation djuk pkgrs gSa rks Documentation dks /** . . . */ ds chp esa fy[krs gSaA bl izdkj ds Documentation dks Java Developer’s Kit ds Javadoc Tool dk iz;ksx djds ,d vyx Documentation HTML File esa Store fd;k tk ldrk gSA bl Documentation dks vyx File esa Store djus ds fy, ge Command Prompt ij Javadoc Tool dk fuEukuqlkj mi;ksx djds viuh Class ds fy, Documentation File rS;kj dj ldrs gSaA


Java in Hindi Command Prompt> Javadoc // This is Third Comment Style

tc gesa dsoy ,d gh Line dk Comment nsuk gksrk gS] rc ge bl rjhds ls Comment fy[krs gSaA Compiler bl izdkj ds Comments dks Ignore dj nsrk gS ;kuh Compile ugha djrk gSA ,d ckr gesa”kk /;ku j[ksa fd ,d Comment ds vUnj nwljk Comments ugha fy[kk tk ldrkA ;kuh Comments dh Nesting ugha dh tk ldrh gSA tSls /** Madhav is a Union Leader /* and I am his Friend*/ He is a Programmer too.*/ Java esa fdlh Hkh Application Program esa de ls de ,d Class t:j gksrh gS vkSj ml Class esa ,d main() Method gksrk gSA Java dk Compiler blh main() Method ls Java ds Application dh Compiling “kq: djrk gSA Class Statement

bl Program dh igyh Code Line dks nsf[k,% class HelloWorld {

tc bl Program dks Compile fd;k tkrk gS rc ;s Code Line Compiler dks ;s Instruction nsrk gS fd | | “Computer, Java ds bl Program dk uke HelloWorld Assign dj nsA”

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tSlkfd geus igys Hkh crk;k Fkk fd ,d Program ds :i esa ge Computer dks ftrus Hkh Instructions nsrs gSa] os lHkh Statements dgykrs gSaA ;gka class Statement og rjhdk gS] ftlls ge gekjs Program dks ,d uke nsrs gSaA ;s Statement dbZ vU; ckrksa dks Hkh Determine djrk gS ftlds ckjs esa ge vkxs i
;s Line Computer dks dgrh gS fd | | “Program dk Main Part ;gka ls “kq: gks jgk gSA”

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Java dk Program dbZ Sections esa Organized jgrk gS] blfy, gesa ,d ,sls rjhds dh t:jr gksrh gS ftlls ;s irk py lds fd Program dk dkSulk fgLlk igys Handle gksxk vkSj


Java in Hindi dkSulk ckn esaA ;gka ls vkxs ge ftrus Hkh Application Programs Create djsaxs] mu lHkh esa main Part gh Starting Point gksxkA Bracket Mark

ge ns[k ldrs gSa fd gekjs Program esa Brackets dk Hkh iz;ksx gqvk gSA ;s Bracket fdlh Hkh Java Program dk cgqr gh egRoiw.kZ fgLlk gSaA Java esa ;s Bracket Program ds fofHkUu fgLlksa dks Group djus dk rjhdk gSA Bracket dh rjg gh Parenthesis dk Hkh iz;ksx fd;k tkrk gSA Opening Bracket o Closing Bracket ds chp tks dqN Hkh fy[kk tkrk gS] og lcdqN ml Group dk fgLlk gksrk gSA Opening o Closing Bracket ds chp fy[ks Statements dks Block dgk tkrk gSA

ge gesa”kk gekjs Program ds fofHkUu fgLlksa dh “kq:vkr dks n”kkZus ds fy, Opening Bracket “{“ dk iz;ksx djrs gSa vkSj fdlh fo”ks’k fgLls dk vUr n”kkZus ds fy, Closing Bracket “}” dk iz;ksx djrs gSaA ,d Block ds vUnj nwljs Block dks Use fd;k tk ldrk gS] tSlkfd gekjs Program esa HelloWorld Class ds Block esa Main() Method ds Block Use fd;k x;k gSA main() Method Block ds vUnj tks Hkh Statement fy[ks tkrs gSa] os lHkh Statements Computer ds fy, Instructions ;k Commands gksrs gSa ftUgsa Computer Execute djrk gSA geus main() Method esa fuEukuqlkj dsoy ,d gh Statement fy[kk gS& System.out.println(“Hello World”);

//Display this String

;s Statement Screen ij ml Data ;k Information dks Print dj nsrk gS] ftls bl Statement ds Parenthesis esa fy[kk tkrk gSA tSls ;fn ge “Hello World” ds LFkku ij “Java Is a Web Language” fy[k nsa] rks Hello World ds LFkku ij ;gh Statement Screen ij Print gksxkA tc fdlh Characters ds ,d lewg dks Double Quote ds chp fy[kk tkrk gS] rks bl Characters ds lewg dks String dgk tkrk gSA ;kuh “Hello World” o “Java Is A Web Language” nksuksa Strings gSa] D;ksafd ;s Characters dk ,d lewg gSa ftUgsa Double Quote ds chp fy[kk x;k gSA bl rjg ls geus Java dk ,d lk/kkj.k lk Program cuk;kA gesa blh rjg ls tkok esa fofHkUu Programs Develop djus gksrs gSaA ge pkgs tks Hkh Program cukuk pkgsa] gesa fuEu Statements rks gesa”kk fy[kus gh gksrs gSa tks Compiler dks crkrk gS fd Program dh “kq:vkr o vUr dgka ij gks jgk gSA public class ClassName //Name of the Class of the Java Program { //Starting of Program Level Class Block //Other program specific statements } //End of the Program Level Class Block Javac Compiler ls ge fdlh Hkh Java Class dks Compile dj ldrs gSa] ysfdu java Interpreter ls ogh Class Command Prompt ij Run gksrh gS] ftlesa main() Method gksrk


Java in Hindi gSA blfy, ftl Class esa main() Method gksrk gS] ml Class dk uke gh ml Class dh Source File dk uke Hkh gksuk t:jh gksrk gSA pwafd tkok ,d Highly Case Sensitive Language gS] blfy, ftl izdkj dk uke ge Class dk fy[krs gSa] mlh rjhds dk uke gesa Source File dk Hkh j[kuk gksrk gSA lkFk gh Source File dk uke gesa”kk .java Extension ds lkFk fy[kk tkrk gS] rHkh javac Compiler mls Compile dj ldrk gSA gesa gekjs Program ds ftrus Hkh Codes fy[kus gksrs gSa] os lHkh Codes ;k Statements gesa Class Block ds vUnj gh fy[kus gksrs gSaA

Java – Applet

tkok Applet Internet Computing esa Use fd, tkus okys NksVs&NksVs Programs gksrs gSaA bu Programs dks ,d Computer ls nwljs Computer esa Internet ij Transport fd;k tk ldrk gS vkSj Applet Viewer ;k fdlh Java Enabled Web Browser }kjk Run fd;k tk ldrk gSA fdlh Hkh vU; Application Program dh rjg gh ,d Applet Hkh gekjs fy, dbZ t:jh dke dj ldrs gSaA mnkgj.k ds fy, Applet fofHkUu izdkj ds Arithmetical Operations Perform dj ldrs gSa] Applet esa fofHkUu izdkj ds Graphics Display gks ldrs gSa tks fd Web Page ij fn[kkbZ nsrs gSa] ;s Applets fofHkUu izdkj ds Sounds Play dj ldrs gSa vkSj Browser esa fofHkUu izdkj ds Animations Display dj ldrs gSaA ;kuh ,d Web Browser esa Java Applets dks Use djds ge fdlh Web Site esa Multimedia dks Use djds Web Page dks vf/kd mi;ksxh] Informative, ljy] Interactive o Dynamic cuk ldrs gSaA tkok ds dkj.k gh ge Internet ds vkt ds Lo:i dks ns[k ldrs gSa ftlesa
Applet – Local and Remote fdlh Applet dks ge Web Page esa nks rjhdksa ls Embed dj ldrs gSaA igys rjhds esa ge gekjk Lo;a dk Web Page cukrs gSa vkSj mlesa Applet dks Embed dj nsrs gSaA nwljs rjhds esa ge fdlh Applet dks fdlh Remote Computer System ls Download djrs gSa vkSj fQj mls vius Web Page esa Embed dj ysrs gSaA


Java in Hindi ,d ,slk Applet ftls Local Computer ij Develop fd;k x;k gks vkSj mlh Local System ij ml Applet dks Store fd;k x;k gks] rks bl izdkj ds Applet dks Local Applet dgrs gSaA tc ,d Local Web Page fdlh Local Applet dks [kkstrk gS] rc mldk Internet ls Connected jguk t:jh ugha gksrk gSA ,slk Web Page lkekU;r;k Local Computer dh fofHkUu Directories dks Search djds Applet dks [kkstrk gS vkSj Web Page esa Load dj nsrk gSA Remote Applet ,slk Applet gksrk gS ftls fdlh vU; Developer us Develop fd;k gksrk gS vkSj fdlh ,sls Computer System ij Store fd;k gksrk gS tks fd Internet ls Connected gksrk gSA ;fn gekjk Computer Internet ls Connected gks rks ge ml Remote Applet dks Internet }kjk Download djds vius Local Computer System ij Run dj ldrs gSaA

fdlh Remote Computer ij j[ks Remote Applet dks [kkstus o vius Computer System ds Web Browser esa Load djus ds fy, gesa ml Applet ds Web Address dh tkudkjh gksuk t:jh gksrk gSA fdlh Applet ds bl Web Address dks Uniform Resource Locator (URL) dgrs gSa vkSj bl Address dks gesa gekjh HTML File esa APPLET Tag ds CODEBASE Attribute ds ,d eku ds :i esa Specify djuk gksrk gSA ge fdlh Remote Applet dks viuh HTML File esa fuEu Code Statement }kjk Specify dj ldrs gSa% CODEBASE = http:// www.achyut.com/applets

ysfdu tc ge Local System ij fdlh Applet dks Locate djuk pkgrs gSa] rc bl CODEBASE Tag esa gesa gekjs Applet ds Local Address ;kuh Applet dk Directory Path nsuk gksrk gSA Clients and Servers ;fn fdlh User dks fdlh Applet dh t:jr gS vkSj og Applet mlds Computer ij miyC/k ugha gS] rks og User ml Applet dks fdlh Remote Computer ls izkIr djds Use dj ldrk gSA mls ;s tkuus dh t:jr ugha gksrh gS fd og Applet fdl Remote Computer ij fLFkr gS ;k fdl rjg ls cuk gSA ,d rjg ls ns[kk tk, rks ,d User Internet }kjk iwjh nqfu;ka ds Computers ls tqM tkrk gS vkSj ftl izdkj dh lwpuk pkgs ml rjg dh lwpuk dks Internet ls Applet ds :i esa izkIr dj ldrk gSA Information Technology (I.T.) dh Hkk’kk esa dgsa rks ftl Computer ls User dks lwpuk,a Applet ;k Web Pages ds :i esa izkIr gksrh gSa] ml Remote Computer dks Server dgrs gSa vkSj User dk Local Computer tks fd Applet ;k Web Pages }kjk fdlh izdkj dh Information dks Server ls izkIr djuk pkgrk gS] mls Client dgrs gSaA

bl rjg ls ,d Local Computer ds Browser o ,d Remote Computer ls vkus okys Applet dh Information ds chp esa Client/Server dh Relationship cu tkrh gSA bl fLFkfr esa Client og gksrk gS] tks Web Page ds HTML Documents dks vius Local Computer ij Download djrk gS] tcfd Server og gksrk gS] tks Web Pages dks Client ds Computer ij Upload djrk gSA User dk Computer gesa”kk Client ugha gksrk gS vkSj Remote Computer gesa”kk Server ugha gksrk gSA dc dkSulk Computer Client gksxk vkSj dc dkSulk Computer Server gksxk] ;s bl ckr ij fuHkZj gksrk gS fd fdlh le; dkSulk Computer fdl rjg dk dke dj jgk gSA


Java in Hindi mnkgj.k ds fy, tc ,d User fdlh Web Site dk Address vius Browser esa Fill djds Internet ls ml Web Page dks ns[kuk pkgrk gS] ml le; og Web Page ftl Computer ij gksrk gS] og Remote Computer Server gksrk gS vkSj User dk Local Computer Client gksrk gSA ysfdu tSls gh Web Page User ds Computer esa Download gks tkrk gS vkSj User fdlh vU; Web Page dks Search djus ds fy, fdlh Search Engine esa dqN Texts Input djrk gS] oSls gh User dk Computer Server cu tkrk gS vkSj File dks Search djus okyk Program Client cu tkrk gSA

Difference – Applet and Application

Applications o Applets nksuksa gh tkok Programs gksrs gSa] ysfdu nksuksa gh izdkj ds Programs esa dqN vUrj gksrk gSA Applets dHkh Hkh Full Featured Application Programs

ugha gksrs gSaA lkekU;r;k bUgsa fdlh NksVs ls dke dks iwjk djus ds fy, fy[kk tkrk gSA pwafd bUgsa Internet ij Run djus ds fy, Design fd;k x;k gS] blfy, budh Design dh dqN lhek,a gSaA Applets esa Codes ds Initialization ds fy, main() Method ugha gksrk gSA tc Applets Web Browser esa Load gksrs gSa] rc Applet ds Codes Automatically Applet Class ds dqN Methods dks Call djds Applet dks Start o Execute djrs gSaA Applications dh rjg Applets Lora= :i ls Run ugha gks ldrs gSaA bUgsa Run gksus ds fy, Web Page dh t:jr gksrh gS] ftlesa dqN Codes fy[k dj Applets dks HTML Web Page esa Embed fd;k tkrk gSA Applets dHkh Hkh Local Computer ds Resources dks iwjh rjg ls Access ugha dj ldrs gSaA ;kuh Applets }kjk ge fdlh Local Computer dh fdlh File esa Data dks Write ugha dj ldrs gSa vkSj uk gh Local Computer ij miyC/k fdlh File ds Data dks Read dj ldrs gSaA Applets, Network ij miyC/k fdlh vU; Server ls fdlh izdkj dk dksbZ Communication

ugha dj ldrs gSaA

Applets fdlh Local Computer ds fdlh Program dks Run ugha dj ldrs gSaA

Preparation – The Applet Writing tkok Applet Programs fy[kus ls igys gesa blds fy, dqN rS;kfj;ka dj ysuh pkfg,A lcls igys rks gesa ;s r; djuk gksrk gS fd fdlh Program esa tkok Applet dks dc Use djuk pkfg,A bldk tokc fuEukuqlkj gS% 1 tc gesa gekjs Web Page esa dqN Multimedia Operations dks Perform djuk gks o vius Web Page dks Dynamic o Interactive cukuk gks] rc gesa vius Web Page esa Java Applet dks Use djuk pkfg,A


Java in Hindi mnkgj.k ds fy, Share–Market dks gh ysrs gSaA tc Trading gks jgh gksrh gS] rc gj {k.k fofHkUu Shares dh dherksa esa Change gksrk jgrk gSA bu dherksa ds vk/kkj ij fofHkUu izdkj ds Dynamic Graph cuk, tkrs gSaA bu fofHkUu izdkj ds Graphs dks Computer esa Web Page ij Dynamically rHkh n”kkZ;k tk ldrk gS] tc ge Web Page esa Multimedia dks Use djsa vkSj Web Page ij Multimedia Use djus dh lqfo/kk gesa tkok Applet }kjk izkIr gksrh gSA 2 tc gesa gekjs Web Page esa dqN Flash Outputs iznku djus gksrs gSa] rc Hkh gesa Java Applets dks Use djuk t:jh gks tkrk gSA tSls ekuyks fd gekjs Web Page dks ;fn dksbZ Hacker Hack djus dh dksf”k”k djs] rks Web Page ls ,d fo”ks’k izdkj dh Sound Play gksuh pkfg,] vkSj Web Page ds dqN Matters Blink gksus pkfg, ;fn ge gekjs Web Page esa bl izdkj dh lqfo/kk pkgrs gSa] rks gesa gekjs Web Page esa Java Applet dks Use djuk pkfg,A 3 tc ge fdlh Program dks Develop djrs gSa vkSj mls vU; Users ds mi;ksx ds fy, Internet ij miyC/k djokuk pkgrs gSa] rc gesa tkok Applet dk mi;ksx djuk pkfg,A

System Package – Predefined (Built-In) Library of Java Classes Reusability Object Oriented Programming System (OOPS) dk ,d egRoiw.kZ Concept gSA bl Concept ds vUrxZr ge fdlh dke dks djus ds fy, ftl Coding dks ,d ckj fy[k nsrs gSa] ml Coding dk iz;ksx ckj&ckj dj ldrs gSaA tkok ,d iw.kZ Object Oriented Programming Language gS] blfy, tkok esa ge OOPS ds bl Concept dks iwjh rjg ls Apply dj ldrs gSa vkSj fofHkUu izdkj ds Common Program Codes dks bl rjg ls fy[k dj Store dj ldrs gSa] ftUgsa fcuk nqckjk fy[ks ;k Modify fd, T;ksa dk T;ksa fQj ls Use dj ldsA tkok esa bl dke dks ftl Concept ds vk/kkj ij Perform fd;k tkrk gS] mls Package dgrs gSaA Package dks ge ,slh Classes dh Library Hkh dg ldrs gSa] ftUgsa ckj&ckj Use fd;k tk ldrk gSA ;fn nwljs “kCnksa esa dgsa rks dg ldrs gSa fd Particular fdlh ,d dke dks djus ls lEcaf/kr lHkh Classes dks ;fn ,d Group ds :i esa ifjHkkf’kr djds Store dj fn;k tk,] rks tkok esa bl Classes ds bl Group dks Package dgrs gSaA ;kuh ,d Package ,d gh dke ls lEcaf/kr fofHkUu izdkj dh Classes dk ,d Container gksrk gSA Java API (Application Programming Interface) Programmer dks Application Development ls lEcaf/kr fofHkUu izdkj ds Predefined Components iznku djrk gSA bu fofHkUu izdkj ds Predefined Components (Program Codes) dks muds dke ds vk/kkj ij fofHkUu izdkj ds Group esa foHkkftr fd;k x;k gS] ftUgsa Package dgrs gSaA

tkok esa ge tks Hkh Program cukrs gSa] muesa fofHkUu izdkj dh Predefined Classes dks Use djrs gSa] tks fd fdlh uk fdlh Package dk fgLlk gksrs gSa vkSj ;s lHkh Packages Java API


Java in Hindi ds fgLls gSaA blfy, ge Directly ;k Indirectly Java API dks Use djds gh viuk Program cukrs gSaA ;fn ge lkjka”k esa dgsa rks dg ldrs gSa fd Java gesa dqN Built-In ;k Predefined Classes iznku djrk gS] ftUgsa ge fcuk fdlh izdkj dk Modification fd, T;ksa dk R;ksa vius Program esa Reuse dj ldrs gSaA bu Predefined Classes dks mudh Functionality ds vk/kkj ij Group esa Store fd, x, gSa] ftUgsa Packages dgrs gSa vkSj ;s fofHkUu izdkj ds Packages Java API ds fgLls gSaA blfy, ;fn ge fdlh Java Package dks vius Program esa Use djuk pkgsa] rks gesa ml Package dks vius Program esa Use djuk t:jh gksrk gSA

Using – The System Packages tkok esa fofHkUu izdkj ds Packages dks Hierarchical Structure esa Organize fd;k x;k gSA fofHkUu izdkj dh Classes fofHkUu izdkj ds Packages esa Stored jgrs gSa vkSj fofHkUu izdkj ds Packages Java API uke ds Java Platform ds fgLls gSaA bl fuEukuqlkj fp= }kjk ljyrk ls le> ldrs gSa%

fofHkUu izdkj dh Required Classes dks muds Package ls vius Program esa Reuse djds Access djus ds nks rjhds gSaA igyk rjhdk ;s gS fd vius Program esa ftl Class dh t:jr gS mlh Class dks vius Program esa Include fd;k tk,A dsoy Required Class dks gh vius Program esa Include djus ds fy, gesa ml Class dk iwjk Qualified uke fy[kuk t:jh gksrk gSA mnkgj.k ds fy, eku yks fd gesa gekjs Program esa awt Package ds dsoy Color Class o Font Class dh t:jr gS] rks dsoy bu nksuksa Class dks vius Program esa Reuse djus ds fy, gesa fuEu fuEukuqlkj Statement fy[kuk gksxk% import import

java.awt.Color ; java.awt.Font ;

ge tkurs gSa fd lHkh izdkj ds Packages Java API dk fgLlk gSa] blfy, gesa ftl fdlh Hkh Package dh Class dks Use djuk gks] Java ds lkFk ml Package ds uke dks Dot Operator ds lkFk fy[kuk gksxkA


Java in Hindi gkykafd awt Package esa dbZ Classes o Subclasses gSa] ysfdu gesa dsoy Color Class ds Codes o Font Class ds Codes dks gh vius Source Program esa Reuse djuk gS] blfy, geus Package ds uke ds lkFk ml Required Class ds uke dks Dot Operator }kjk Specify dj fn;k gSA gekjs Source Program esa fdlh Predefined Class ds Codes dks Include djus dk dke import uke dk “kCn djrk gS] tks fd Java dk ,d Keyword ;k Reserve Word gSA Keyword / Reserve Word Keyword ;k Reserve Word dqN ,sls “kCn gksrs gSa] ftudk tkok Compiler ds fy, fo”ks’k vFkZ gksrk gSA tc Hkh ge gekjs Program esa fdlh Keyword dks Use djrs gSa] tkok Compiler ml Keyword ds fy, fu/kkZfjr dke djus ds fy, ck/; gks tkrk gSA mnkgj.k ds fy, ;fn ge import Statement dks gh ysa] rks tkok Compiler dks tSls gh import Keyword izkIr gksrk gS] og ml Predefined Program Code dks Source Program esa Reuse dj ysrk gS] ftldk uke bl Keyword ds ckn fy[kk x;k gksrk gSA ;fn gesa gekjs Program esa Particular fdlh ,d gh Class dks Use djuk gks] rks mijksDr rjhds ls ml Class dks vius Source Program esa Reuse fd;k tk ldrk gSA ysfdu ;fn gesa Particular fdlh ,d Class dh ugha cfYd fdlh Package dh lHkh Classes dh vius Source Program esa t:jr gks] rks gesa * Operator dk fuEukuqlkj iz;ksx djuk t:jh gksrk gS% import import

java.awt.* ; java.applet.*.

tc ge bl rjg dk Statement fy[krs gSa] rks bldk eryc gksrk gS] fd ge awt Package dh lHkh Predefined Classes dks vius Source Program esa Reuse djus ds fy, Import dj jgs gSa] tks fd Lo;a java uke ds Package esa miyC/k gSA blh rjg ls nwljs Statement }kjk ge applet Package dh lHkh Classes dks vius Program esa fcuk fQj ls fy[ks gq, Use dj jgs gSa] tks fd Lo;a java uke ds Package esa miyC/k gSA bl rjg ls ge nks rjhdksa ls fdlh igys ls cuh Class dks mldh Class Library }kjk Access djds vius Program esa Use dj ldrs gSaA ;fn ge pkgsa rks fcuk import Keyword dk Use fd, gq, Hkh fdlh Predefined Package ds fdlh Class dks Directly Access dj ldrs gSaA blds fy, gesa Class dks Access djrs gh mldk Object Create djuk t:jh gksrk gSA ;kuh

java.awt.Button OKBtn;

bl rjg ls ge gekjs Program esa fcuk import Statement dk iz;ksx fd, gq, Hkh Predefined Button Class dks Use dj ldrs gSa] ysfdu ;s Class dsoy OKBtn Object ds fy, gh mi;ksxh gksxhA ;s Button Create djds gekjs Program ls fQj ls Invisible gks tk,xhA blfy, import Statement dk iz;ksx djds bls vius Program esa Use djuk Bhd jgrk gS] vU;Fkk gesa gj Class dk iwjk Path /;ku j[kuk t:jh gks tkrk gSA


Java in Hindi Building – The Applet Code Applets dks dHkh Hkh Console Mode esa Run ugha fd;k tk ldrk gSA ;s gesa”kk fdlh uk fdlh Browser Window esa ;k fQj ,d Special Program ftls Applet Viewer dgrs gSa] esa gh Run gksrs gSaA pwafd lHkh Java Applets Graphical gksrs gSa] blfy, bUgsa GUI Mode esa gh Run fd;k tk ldrk gSA tkok esa Graphical User Interface cukus ds fy, AWT (Abstract Windowing Toolkit) uke dh ,d Class Library ;k Package gS] ftlesa Applet ij Graphics Display djus ls lEcaf/kr fofHkUu izdkj dh Classes dks ifjHkkf’kr fd;k x;k gSA pwafd gj Applet ,d Window esa Run gksrk gS] blfy, gj Applet ds fy, gesa Window Support dks izkIr djuk t:jh gksrk gS vkSj Window Creation o Management ls lEcaf/kr tkok dh ftruh Hkh Classes gSa] os lHkh Classes AWT uke ds Package esa miyC/k gSa] blfy, gesa bl Package dks vius gj Applet Program esa Include djuk t:jh gksrk gSA pwafd fdlh Applet dks gesa”kk GUI Form esa gh Display fd;k tk ldrk gS] blfy, fdlh Applet dks GUI Form esa Display djus ds fy, ftu Functionality dh t:jr gksrh gS] mUgsa applet uke ds ,d Package esa Predefine dj fn;k x;k gS] ftUgsa ge fcuk Extra Coding fd, gq, T;ksa dk R;ksa Reuse dj ldrs gSaA vr% ;fn ge Applet Development dj jgs gSa] rks gesa bl Package dks Hkh vius Source Program esa Import djuk t:jh gksrk gS rkfd ge Applet ls lEcaf/kr lkekU; Functionality dks izkIr dj ldsaA bl izdkj ge le> ldrs gSa fd ,d Applet Develop djus ds fy, gesa applet Package vkSj awt Package dks vius Program esa Include djuk t:jh gksrk gS vkSj bUgsa viuh Source File esa Include djus ds fy, gesa fuEu Statement fy[kus gksrs gSaA import java.applet.*; import java.awt.*;

// Statement 01 // Statement 02

Applet Package – The Applet Class applet Package Java API dk lcls NksVk Package gS vkSj Applet Class bl Package dh bdykSrh Class gSA applet Package esa Applet Class ds vykok nwljh dksbZ Class gh ugha gSA tc Hkh ge fdlh ,sls Web Page dks Open djrs gSa] ftlesa Applet Embed gksrk gS] rks og Applet Automatically Browser esa Load gks tkrk gSA pwafd Applet gesa”kk fdlh uk fdlh HTML File ;k Web Page esa Run gksrs gSa] tks fd fdlh uk fdlh Browser esa Load gksrs gSa] blfy, Applet ds bl Environment dks “Context of the Applet” dgk tkrk gSA Applets o Applications nksuksa dks gh Compile djus ds fy, gesa javac Compiler dk iz;ksx djuk iMrk gS] tcfd ,d Console Mode Application dks Execute djus ds fy, gesa java Interpreter dk iz;ksx djuk iMrk gS vkSj ,d GUI Applet dks Execute djus ds fy, gesa Appletviewer dk iz;ksx djuk iMrk gSA fdlh Applet dks ge ,sls Browser }kjk Hkh ns[k ldrs gSa] tks Java Enabled gksA Netscape Navigator ,d Java Enabled Browser gS] ftlesa Applets dks fcuk Appletviewer dk iz;ksx fd, ns[kk tk ldrk gSA


Java in Hindi OOPS and OOPL – The Definition

ge Computer ij tks Hkh Program cukrs gSa oks Program fdlh uk fdlh Real Life Problem dks Solve djus ds fy, cukrs gSa vkSj gj Real World Problem esa Real World Objects gksrs gSaA bl fLFkfr esa OOPS ,d ,slk Concept gS ftlds vk/kkj ij ge fofHkUu izdkj dh Real Life ls Related Problems dks Solve djus ds fy, gekjh leL;k ls lEcaf/kr fofHkUu Real World ds Physical Objects dks Computer esa Logically Represent dj ldrs gSa vkSj ml Real Life ls lEcaf/kr leL;k dks Computer esa Logically Hkh mlh rjg ls Solve dj ldrs gSa] ftl rjg ls ml leL;k dks Real World esa Physically Solve djrs gSaA fdlh Problem dks Solve djus dk og System ;k rjhdk ftlds vk/kkj ij fdlh Real World Problem dks Solve djus ds fy, ml Real World Problem ls lEcaf/kr Physical Objects dks Computer esa Logically Represent djds Problem dks Computer }kjk Solve fd;k tk lds] Object Oriented Programming System (OOPS) dgykrk gS vkSj ftl Computer Programming Language esa OOPS ds Concepts dks Bhd rjg ls Implement fd;k tk ldrk gS] ml Programming Language dks Object Oriented Programming Language (OOPL) dgk tkrk gSA tkok ,d ,slh gh Object Oriented Programming Language gS] ftlesa fdlh Real World leL;k ls lEcaf/kr fofHkUu Real World Physical Objects dks Computer esa Logically Represent djds leL;k dks mlh izdkj ls Logically Solve fd;k tk ldrk gS] ftl rjg ls ml leL;k dks Real World esa Physically Solve fd;k tkrk gSA

Problem – The Definition nqfu;ka ds gj dke dks lEiUu djus ds fy, gesa ,d fo”ks’k Øe dk ikyu djuk iMrk gS vkSj tc ge fdlh dke dks Bhd rjhds ls dj ysrs gSa] rks ifj.kke Lo:i gesa dqN uk dqN mfpr Output izkIr gksrk gSA Bhd blh rjhds ls Computer ls Hkh fdlh dke dks djokus ds fy, gesa mlls ,d fo”ks’k Øe dk ikyu djokuk iMrk gS vkSj tc Computer gekjs crk, x, fdlh Øe ds vuqlkj dke dj ysrk gS] rks gesa dqN uk dqN mfpr ifj.kke Hkh izkIr gksrk gSA ftl fdlh Hkh dke dks djus ds fy, gesa fdlh fo”ks’k Øe dk ikyu djuk iMrk gS] ml dke dks ge ,d Problem dg ldrs gSaA bl fLFkfr esa gj dke ,d izdkj dh leL;k gksrh gS D;ksafd nqfu;ka ds fdlh Hkh NksVs ls NksVs dke dks lEiUu djus ds fy, Hkh gesa fdlh uk fdlh Øe dk ikyu rks djuk gh iMrk gSA ,d mnkgj.k ls le>sa rks ;fn gesa ikuh ihuk gks rks Hkh gesa ,d fuf”pr Øe dk ikyu djuk iMrk gSA ikuh ihus ds fy, Hkh gesa% 1 2 3 4

lcls igys fxykl ysuk iMsxkA fxykl esa ikuh ysuk iMsxkA fQj ml ikuh dks eqag rd ykuk iMsxk ikuh eqag esa tk,xk vkSj r`fIr dk vglkl gksxkA

[ Variable Declaration ] [ Input ] [ Process ] [ Output ]

;kuh ikuh ihus ds fy, Hkh gesa ,d fuf”pr Øe dk ikyu djuk iM jgk gS] blfy, ikuh ihus dks Hkh ge ,d izdkj dh leL;k ds :i esa ns[k ldrs gSaA


Java in Hindi Data – Value OR a Set of Values

ewy :i ls ns[kk tk, rks Computer ds fy, fdlh Hkh izdkj dk eku ;k ekuksa dk lewg Data dgykrk gSA Computer esa ge fdlh Hkh eku dks eq[;r% rhu izdkj ls Specify dj ldrs gSaA Integer tc gesa Computer esa fdlh ,sls eku dks Store djuk gksrk gS] ftlesa dsoy iw.kZ la[;k,a gh gksrh gSa] rc ml Value dks Integer izdkj dh Value dgk tkrk gSA Float tc gesa Computer esa fdlh ,sls eku dks Store djuk gksrk gS ftlesa nleyo okyh la[;k gksrh gS] rc ml Value dks Float izdkj dh Value dgk tkrk gSA Character tc gesa Computer esa dsoy Characters Store djus gksrs gSa] rc bl izdkj ds eku dks Character izdkj dk eku dgrs gSaA

Object – The Definition

nqfu;ka dh gj ml pht dks Object dg ldrs gSa] ftls Physically ns[kk tk lds ;k Logically fdlh fn[kkbZ nsus okyh pht ds Reference esa eglwl fd;k tk ldsA tSlkfd geus dgk fd Object dks ns[kk tk ldrk gS] bldk eryc ;s gqvk fd gj og pht ftldk dksbZ jax] :i o vkdkj gks og Object gSA tSls fd Keyboard, Employee, Client vkfnA blh izdkj ls gj og pht ftls fdlh fn[kkbZ nsus okyh pht ds Reference esa eglwl fd;k tk lds] Object gSA tSls Bank Account.

gj Object dh dqN fo”ks’krk,a gksrh gSa] ftldh otg ls dksbZ ,d Object fdlh nwljs Object ls vyx igpkuk tkrk gSA fdlh Hkh Object dh bu fo”ks’krkvksa dks ge ml Object ds Attributes ;k ml Object dh Properties dgrs gSaA fdlh Object ds Attribute ds eku esa ifjorZu djus ij og Object cny tkrk gSA mnkgj.k ds fy, fdlh Account Object dh ,d Property, mldk Account Number gks ldrk gSA vc ;fn fdlh Account ds Account Number Property dk eku Change fd;k tk,] rks og Account fdlh nwljs Account Object dks Refer djus yxrk gSA ;kuh Object ds Attribute ds eku esa ;fn ifjorZu dj fn;k tk, rks Object cny tkrk gSA ftl rjg ls gj Object Uniquely Identify gksus ds fy, vius dqN Unique Attributes dk iz;ksx djrk gS] mlh rjg ls gj Object fdlh uk fdlh rjhds ls dksbZ uk dksbZ dke djrk gSA Object ds bl dke djus dh izo`fr dks Object dk Behavior dgrs gSaA


Java in Hindi Objects – Based on Problem

okLrfod thou (Real World) esa ge fdlh Hkh leL;k dks ftl izdkj ls ns[krs gSa] mlh izdkj ls ge ml leL;k dks Computer esa Hkh Represent dj ldrs gSaA leL;k dks Computer esa Logically rHkh Represent fd;k tk ldrk gS] tc leL;k dks Bhd izdkj ls le>k tk, vkSj ;s irk fd;k tk, fd leL;k ds eq[; Objects dkSu&dkSu ls gSaA mnkgj.k ds fy, eku yhft, fd ,d Company esa mlds lHkh Employees ds Bio – Data dks Manual Register ls Upgrade djds Computerized djuk gSA vc gesa lcls igys bl Real World leL;k ls lEcaf/kr lcls egRoiw.kZ Object dks Identify djuk gSA pwafd] fofHkUu Employees ds Bio – Data dks Computer ij Store djuk gS] blfy, bl leL;k ls lEcaf/kr tks lcls egRoiw.kZ Object gS] og Employee gh gSA Employee ,d Physical Object gS vkSj bls tc Computer esa Represent fd;k tk,xk rks] Computer esa og Employee Logical Object dgyk,xkA

Abstraction – The Problem Simplifying Process

fdlh Hkh Real Life Problem dks tc gesa Computer ij Logically Represent djuk gksrk gS] rks lcls igys gesa ;s r; djuk gksrk gS fd leL;k ls lEcaf/kr os t:jh phtsa dkSu&dkSu lh gSa] tks leL;k ds ifj.kke dks izHkkfor djrh gSaA leL;k ds lek/kku dks izHkkfor djus okyh t:jh ckrksa dks leL;k ds lek/kku dks izHkkfor uk djus okyh fcuk t:jh ckrksa ls vyx djus dh izfØ;k dks Abstraction dgrs gSaA OOPS ds bl Concept dks ge fiNys mnkgj.k }kjk gh le>us dh dksf”k”k djrs gSaA ekuyks fd fdlh Company ds fofHkUu Employees ds Bio – Data dks Computer ij Store djuk gSA pwafd bl dke dks lEiUu djus ds fy, ,d fuf”pr Øe dk ikyu djuk iMrk gS] blfy, Computer ds fy, ;s dke ,d izdkj dh leL;k gS] ftls Solve djuk gSA vc pwafd gekjh leL;k dk eq[; Object Employee gS] blfy, mlds dbZ Attributes gks ldrs gSa tks ,d Employee dks nwljs Employee ls Uniquely Identify djus esa enn djrs gSaA Employee dh fofHkUu Properties esa ls dqN fuEukuqlkj gks ldrs gSa% • • • • • • • • • • • • • •

Employee’s First Name Employee’s Last Name Address City District State Date Of Birth Qualification Extra Ability Degrees Designation Date Of Company Joining Hobbies Contact Number


Java in Hindi • • •

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No. of His Brothers and Sisters His Father’s Date of Birth His Father’s Name His Friends Contact Number

ge ns[k ldrs gSa fd blh rjg ls ,d Employee dh blls Hkh T;knk Properties gks ldrh gSa] ftuds vk/kkj ij mls Uniquely fdlh nwljs Employee ls vyx Identify fd;k tk ldsA ysfdu bl List esa ge ns[k ldrs gSa] fd Employee ds dqN Attributes ,sls gSa] ftudk Employee ds Bio–Data ;kuh eq[; leL;k ds ifj.kke ls dksbZ lEca/k ugha gSA tSls fd Employee ds fdrus HkkbZ&cgu gSa] bl ckr dk Employee ds Bio–Data ls dksbZ lEca/k ugha gSA blh rjg ls Employee ds firk ds Date of Birth dk Employee ds Bio–Data ls dksbZ lEcU/k ugha gS vkSj Employee ds nksLr ds Contact Number dk dksbZ lEca/k Employee ds Bio–Data ls ugha gSaA ;kuh ;s rhu Attributes ,sls Attributes gSa] ftudk Employee ds Bio–Data ls dksbZ lEca/k ugha gSA blfy, bu fcuk t:jh Data dks ckdh ds t:jh Data ls vyx dj nsus ij gekjs lkeus fuEukuqlkj Attributes vkrs gSa% • • • • • • • • • • • • • • •

Employee’s First Name Employee’s Last Name Address City District State Date Of Birth Qualification Extra Ability Degrees Designation Date Of Company Joining Hobbies Contact Number His Father’s Name

bl izdkj ls geus leL;k (Bio–Data of Employee) ds ifj.kke dks izHkkfor djus okys t:jh Attributes dks leL;k ls vlEcaf/kr fcuk t:jh Attributes ls vyx fd;kA bl izfØ;k dks Abstraction dgrs gSa vkSj gesa leL;k ds ifj.kke dks izHkkfor djus okys tks t:jh Attributes izkIr gq, gSa] bu Attributes dks Abstract Attributes dgrs gSaA

Abstract Data Type - Logical Representation of a Real World Object

ge ns[k ldrs gSa fd Bio – Data Problem ls lEcaf/kr Attributes dks izkIr djus ds fy, geus lcls igys fdlh Employee ds lHkh Attributes ij fopkj fd;k vkSj fQj t:jh Attributes dks fcuk t:jh Attributes ls vyx djds t:jh Attributes dks izkIr dj fy;kA 61 Any Question or Suggestion, Just Discuss Here...

Java in Hindi vc blh leL;k ds Employee Object dks ;fn Computer esa Logically Represent djuk gks] rks gesa bu Abstract Attributes ds vk/kkj ij ,d Abstract Data Type cukuk gksrk gSA bl Abstract Data Type dks Object Oriented Programming Languages esa Class Hkh dgrs gSaA Class ,d u, izdkj dk User Defined Data Type gksrk gS] tks leL;k ls lEcaf/kr fdlh Real World Object dks Computer esa Logically Represent djus ds fy, cuk;k tkrk gSA Class ,d Specification gksrk gS] tks fdlh leL;k ls lEcaf/kr fdlh Real World Object ds fofHkUu Abstract Attributes ds ekuksa dh Computer Memory esa Representation dks Specify

djrk gSA

Attributes – The Data Members of The Class fdlh leL;k ds ifj.kke ls lEcaf/kr fdlh Object ds fofHkUu Attributes dks tc Computer esa Represent djuk gksrk gS] rc Computer esa ml Object ds Attributes esa Store gksus okys Data ds vk/kkj ij ge ;s r; djrs gSa fd Object dk dkSulk Attribute fdl izdkj ds eku (Integer, Character ;k Float) }kjk Represent gks ldrk gSA tks Attribute ftl izdkj ds eku }kjk Represent gks ldrk gS] ml Attribute dks mlh izdkj ds Data Type ds lkFk Declare dj fn;k tkrk gSA Data Type ds lkFk Object ds Attributes dks Declare djus ij Object ds fofHkUu Abstract Attributes Class ds Data Members dgykrs gSaA

blh ckr dks ;fn ge nwljs “kCnksa esa dgsa rks Abstraction ls izkIr Abstract Attributes fdl izdkj ds Data Store djsaxs] bl rF; ij fuHkZj djrs gq, ;k bl ckr dks /;ku esa j[krs gq,] bu fofHkUu Abstract Attributes ds Basic Data Type dks r; fd;k tkrk gSA tc bu Abstract Attributes dks muds Data Type ds lkFk Class esa Specify fd;k tkrk gS] rc bu Abstract Attributes ds Declaration dks Class ds Data Members dgrs gSaA

Behaviors – The Methods of The Class dksbZ Object tks dke djrk gS] mu dkeksa dks ml Object dk Behavior dgrs gSaA ysfdu tc ge fdlh Object dks Computer esa Represent djuk pkgrs gSa] rc ge ;s ugha ns[krs gSa fd Object okLro esa D;k&D;k dj ldrk gS] cfYd ge ;s ns[krs gSa] fd Object ds os dkSu ls dke gSa] ftuds }kjk ,d Object vius fdlh ml Attribute dks Change djrk gS] ftUgsa Abstraction dh izfØ;k }kjk Identify fd;k x;k gSA fdlh leL;k ls lEcaf/kr Abstract Attributes dks ml Object ds tks Behaviors izHkkfor djrs gSa] Object ds os Behaviors gh ml leL;k ls lEcaf/kr Behaviors gSaA tkok esa Object dh Class }kjk bu Behaviors dks Represent djus ds fy, gesa Methods dk iz;ksx djuk gksrk gSA Methods tkok ds os Code Segments gksrs gSa] tks fdlh Object ds fdlh uk fdlh Abstract Attribute ds eku dks fdlh uk fdlh izdkj ls Change djrs gSaA ;kuh os Operations ftUgsa lEiUu djus ij Object ds fdlh uk fdlh Abstract Attribute ds eku esa ifjorZu gks] Methods dgykrs gSaA


Java in Hindi Problem Design (OOPS) v/s Problem Implementation (OOPL)

OOPS o OOPL nksuksa ds vk/kkj ij gesa”kk fdlh Hkh OOPS Concept dh nks ifjHkk’kk,a curh gSaA ,d ifjHkk’kk dsoy OOPS ds Concept dks Represent djus dk dke djrh gS tcfd nwljh ifjHkk’kk ml igyh ifjHkk’kk ds vk/kkj ij fdlh Programming Language esa OOPS ds ml Concept dks Implement djus ls lEcaf/kr gksrh gSA tc ge OOPS ds lEca/k esa dksbZ ifjHkk’kk nsrs gSa] rks og ifjHkk’kk fdlh Real World leL;k o mlls lEcaf/kr fdlh Real World Physical Object ds lEca/k esa vkSj fdlh Software dks Design djus ds lEca/k esa gksrh gSA

ysfdu tc ge OOPS dh fofHkUu ifjHkk’kkvksa dks fdlh Programming Language esa Implement djrs gSa] rc OOPS dk eq[; Purpose ;s gksrk gS fd fdlh Real World Object dks Best rjhds ls fdlh Programming Language esa Logically Represent fd;k tk,] rkfd leL;k ls lEcaf/kr fdlh Real World Object dks Computer esa ,d u, Data Type ftls Abstract Data Type dgrs gSa] ds :i esa Represent fd;k tk ldsA fdlh leL;k dks Solve djus ds fy, ge nks Approach Use dj ldrs gSaA igyk Approach iwjh rjg ls OOPS ds Concepts ij vk/kkfjr gksrk gS vkSj Problem ds Solution dks Design djus ls lEcf/kr gksrk gSA ;kuh ge ,d Hkh Line dh Coding fy[ks fcuk Hkh fdlh Software dks OOPS ds Concept ds vk/kkj ij Design dj ldrs gSaA vUrj dsoy bruk gksxk fd bl Design dk dksbZ izR;{k ifj.kke gesa izkIr ugha gksxkA tcfd OOPS ds vk/kkj ij ge ftl Modal dks cuk,axs ml Modal dks ;fn fdlh OOPL Language esa Implement dj fn;k tk, rks gesa leL;k dk izR;{k ifj.kke izkIr gks tk,xkA bl ckr dks ljy rjhds ls dgsa rks nks la[;kvksa dks tksMus dk Algorithm fy[k nsus ls gesa nks la[;kvksa dk ;ksx izkIr ugha gksxk cfYd nks la[;kvksa dk ;ksx djus ds fy, fdl izdkj ls dke djuk gksxk] ml dke djus dh Process dk irk pysxkA tcfd bl Algorithm ds vk/kkj ij fdlh Programming Language esa Computer Codes fy[k fn, tk,a rks gesa nks la[;kvksa dh Actual tksM izkIr gks tk,xhA ;kuh Algorithm cukuk Problem Design djus ls lEcaf/kr dke gS tcfd Program cukuk ml Algorithm dks Implement djus ls lEcaf/kr dke gSA blh rjg ls OOPS ds Concept dks Apply djuk Problem Design djus ls lEcaf/kr gS tcfd OOPS ds Concept ds vk/kkj ij cuus okys Design dks Computer Language esa Implement djuk Problem Solve djus ls lEcaf/kr dke gSA ge ,slk Hkh dg ldrs gSa fd tc fdlh Problem dks Real World esa Define djuk gksrk gS] rc Problem ds fofHkUu Objects dks Physical :i esa Identify dj ldrs gSa] ysfdu tc mlh Problem dks Computer esa Logical :i esa Define djuk gksrk gS] rc Problem dks ,d u, Data Type ds :i esa Represent djuk gksrk gS] ftls ge fdlh Computer Programming Language esa Abstract Data Type ;k Object dh Class ds :i esa Identify djrs gSaA


Java in Hindi Encapsulation – The Unitizing Process of Attributes and Behaviors

tSlkfd geus igys dgk fd OOPS o OOPL ds vk/kkj ij gj OOPS Concept dh nks ifjHkk’kk,a gksrh gSaA ;gh fu;e OOPS ds Encapsulation Concept ds lEca/k esa Hkh ykxw gksrh gSA tc ge OOPS ds lEca/k esa ns[krs gSa] rks fdlh Object dh Internal Workings dks ;k mlds dke djus ds tfVy rjhdksa dks le>s fcuk mls mi;ksx esa ysus ds fy, dqN O;oLFkk,a dj nsuk] bl izfØ;k dks Encapsulation dgrs gSaA bl Concept dks le>us ds fy, ,d mnkgj.k ns[krs gSaA eku yks fd gekjs ikl ,d Computer gSA vc tc ge Computer dks Switch ON djrs gSa] rks ;s tkus fcuk fd Computer fdl izdkj ls ON gksrk gS] ge Computer dks mi;ksx esa ysrs jgrs gSaA blh rjg ls fdlh Car ds Accelerator dks Press djus ij Car dh Speed fdl izdkj ls csa] rks ifjHkk’kk cny tkrh gSA Programming Language tkok ds lEca/k esa tc ge Encapsulation dks ifjHkkf’kr djuk gksrk gS] rks ge bl Concept dks vxzkuqlkj ifjHkkf’kr djrs gSaA leL;k ls lEcaf/kr Abstracted Attributes dks muds Data Type ds lkFk Specify djus dh Process ls ml Object ds Data Members izkIr gksrs gSa vkSj leL;k ls lEcaf/kr ftu Operations dks Perform djds dksbZ Object vius fdlh Abstract Attribute dh fLFkfr ;k eku esa ifjorZu djrk gS] ml Operation dks Object dk Behavior dgrs gSa] ftls tkok esa Implement djus ds fy, ftu Codes dks fy[krs gSa] mu Code Block dks Methods dgrs gSaA ;kuh fdlh leL;k ls lEcaf/kr Object ds Physical Attributes o Behaviors dks Java esa Implement djus ij Object ds leL;k ls lEcaf/kr fofHkUu Abstracted Attributes dks Data Members o fofHkUu Attributes dks Change djus okys Operations dks Methods ds :i esa Specify djrs gSaA fdlh Hkh Object ds xq.k ;kuh mlds Attributes o mlds Behaviors nksuksa fdlh ,d gh Physical Object ds fgLls gksrs gSaA blfy, Object ds Attributes dks Represent djus okys Data Members o Behaviors dks Represent djus okys Methods nksuksa dks ,d bdkbZ ds :i esa Specify djus dh izfØ;k dks OOPL esa Encapsulation dgrs gSaA Encapsulation ds ckn ;kuh Computer esa fdlh leL;k ls lEcaf/kr Object ds fofHkUu Data Members (Attributes) o Methods (Behaviors) dks Combine djds ,d Unit ds :i esa Encapsulate djus ds ckn tks Specification gesa izkIr gksrk gS] ml Specification dks ;fn ,d uke ns fn;k tk,] rks og Specification leL;k ls lEcaf/kr fdlh Object dh Class dk Representation gksrk gSA

tkok ds fy, ;s ,d u, izdkj dk Data Type gksrk gS] tks fdlh Real World leL;k ls lEcaf/kr fdlh Real World Object dks Computer esa Logically Represent djus esa l{ke gksrk gSA bls Abstract Data Type Hkh dg ldrs gSa] D;ksafd ;s fdlh leL;k ds Abstraction ls izkIr Abstracted Attributes ds vk/kkj ij curk gSA


Java in Hindi Class – A Logical Specification of Problem Related Object

vHkh rd geus OOPS ds ftu Concepts o Elements dks ifjHkkf’kr fd;k gS] muesa ls T;knkrj ifjHkk’kk,a Hkzfer djus okyh o le> esa uk vkus okyh gSaA pfy,] ge bu ifjHkk’kkvksa dks dsoy tkok ds lEca/k esa gh Apply djus dh dksf”k”k djrs gSaA fdlh Hkh Real World Problem dks tc gesa Computer ij Solve djuk gksrk gS] rks lcls igys gesa ;s tkuuk gksrk gS] fd Problem ls lEcaf/kr og lcls egRoiw.kZ Object dkSulk gS] ftl ij leL;k vk/kkfjr gSA Object dks igpkuus dk dksbZ fuf”pr rjhdk ;k Trick ugha gSA gj leL;k esa vyx izdkj dk Object izHkkfor gksrk gS vkSj gj leL;k esa ml vyx izdkj ds Object ds vyx izdkj ds Attributes dks Manage djuk gksrk gSA blfy, fdlh leL;k ds lcls egRoiw.kZ Object dk irk yxkus ds fy, gesa ckj&ckj fofHkUu izdkj dh leL;kvksa dks gy djus dh dksf”k”k djuh gksrh gSA dbZ ckj fdlh leL;k dks Solve djrs le; ge xyr Object ys ysrs gSaA ,sls esa tc ge vkxs c
leL;k ls lEcaf/kr egRoiw.kZ Objects igpkuus ds ckn gesa mu Objects ds mu Attributes dks izkIr djuk gksrk gS] tks leL;k ls lEcaf/kr gksaA pwafd ,d Bank Account o ,d Customer nksuksa ds gh fofHkUu izdkj ds Attributes gks ldrs gSa vkSj ;s t:jh ugha gS fd lHkh Attributes leL;k dks Represent djus ds fy, mi;ksxh gksaA blfy, gesa fdlh Object ds leL;k ls lEcaf/kr t:jh Attributes izkIr djus ds fy, leL;k dk Abstraction djuk gksxkA fdlh leL;k ls lEcaf/kr lcls egRoiw.kZ Object ds leL;k ls lEcaf/kr lcls egRoiw.kZ Attributes izkIr djus dk ;kuh Abstraction djus dk lcls vPNk rjhdk ;s gS fd ge ;s irk djsa fd gekjh leL;k esa Object D;k Operation Perform djsxkA ;kuh Object dke D;k djsxk\ ge tkurs gSa fd dksbZ Object tc Hkh dksbZ dke djrk gS ;k Operation Perform djrk gS] rks fdlh uk fdlh rjhds ls og vius gh fdlh Attribute ds eku esa ifjorZu djrk gSA blfy, ;fn gesa ;s irk py tk, fd gekjh leL;k esa gekjk Object vius fdu Attributes ds ekuksa esa ifjorZu djsxk] rks ge mu ifjofrZr gksus okys ekuksa dks Store djus okys Attributes dks Object 65 Any Question or Suggestion, Just Discuss Here...

Java in Hindi ds t:jh Abstract Attributes ds :i esa ifjHkkf’kr dj ldrs gSa] ;kuh Object ds t:jh Data Members dk irk yxk ldrs gSaA ;fn dksbZ Object dksbZ ,slk Operation Perform djrk gS] ftlls Object ds fdlh Hkh Attribute ds eku esa dksbZ ifjorZu ugha gksrk gS] rks le> ysuk pkfg, fd Object dk og Operation leL;k ls lEcaf/kr t:jh Operation ugha gS vkSj Object ds ml Operation dks Neglect dj nsuk pkfg,A ;fn ge ljy “kCnksa esa dgsa rks dg ldrs gSa fd fdlh leL;k ls lEcaf/kr t:jh Data dk irk yxkus ds fy, gesa ml leL;k ls lEcaf/kr lcls egRoiw.kZ Object ds lEca/k esa ;s iwaNuk pkfg, fd Object ds D;k djus ij D;k gksxkA fdlh Object ds dqN djus ij Object dh ftu fo”ks’krkvksa ds eku cny ldrs gSa] os fo”ks’krk,a gh gekjh leL;k ls lEcaf/kr lcls egRoi.kZ Data gSaA pfy,] blh fu;e dks ge Bank Account Object ij Apply djrs gSaA Bank Account Object dk lcls egRoiw.kZ dke ;s gS fd ge fdlh Bank Account esa viuk /ku Deposit djokrs gSaA ;kuh Bank Account Object /ku dks Deposit djus dk dke djrk gSA blh rjg ls ge fdlh Bank Account esa vius Deposited /ku dks Withdraw djrs gSaA ;kuh Bank Account Object Bank esa tek /ku dks fudkyus dk dke Hkh djrk gSA

bl rjg ls ,d Bank Account Object leL;k ls lEcaf/kr nks gh lcls egRoiw.kZ dke dj jgk gSA gkykafd dqN vU; dke Hkh gksrs gSa] ftUgsa Bank Account Object Perform djrk gS] ysfdu ge ;gka ij ;gh eku jgs gSa fd Bank Object ;gh nks dke djrk gSA tc Bank Account esa /ku Deposit djrs gSa] rc Deposit Form Fill djds :i;ksa ds lkFk ml Form dks Hkh Bank esa tek djokuk iMrk gSA Deposit Form esa gesa fuEu lqpuk,a nsuh gksrh gSa% • • • • • •

Branch Name Branch Number Account Number Account Head Name Money Date

blh rjg ls ;fn Bank ls :i, Withdraw djus gksa] rks ,d Withdrawal Form Fill djds tek djokuk iMrk gSA ml Withdrawal Form esa fuEu lqpuk,a nsuh gksrh gSa% • • • • • •


;s lHkh fdlh Bank Account ds os Attributes gSa] ftUgsa Deposit ;k Withdraw Operation }kjk Change fd;k tkrk gSA blfy, ;s lHkh Attributes Bank Account Object ds Abstract Attributes gSa vkSj Deposit o Withdraw os Operations gSa tks t:jr ds vk/kkj ij bu Abstract Attributes dks Change djus ds fy, Use Perform ;k Execute gksrs gSaA


Java in Hindi bl rjg ls gesa Account Object ds fy, nks Operations o 6 Abstract Attributes izkIr gksrs gSaA bUgh Operations o Attributes dks ge ,d Abstract Data Type ;k ,d tkok Class ds :i esa Specify djsa] rks cuus okyk Description leL;k ls lEcaf/kr Real World Object (Account) dks Computer esa Logically Represent djrk gSA leL;k ls lEcaf/kr Account Object ds fofHkUu Abstract Attributes esa ge fuEu izdkj ds Data Feed dj ldrs gSa% • • • • •

•


= = = = = =

Jaipur JPR01 AC1201235 Achyut 2000.00 12-July-2007

ftu Attributes ds ekuksa ds lkFk fdlh izdkj dh Calculation gks ldrh gS] mu Attributes dks Integer ;k Float izdkj dk Declare fd;k tkuk gksrk gSA pwafd Bank Account dk Money Attribute ,d ,slk Attribute ftlds eku ds lkFk fdlh izdkj dh Calculation gks ldrh gS] lkFk gh ;s eku nleyo okyk gS blfy, bl eku dks Hold djus ds fy, Float izdkj ds Data Type ds Variable dh t:jr iMsxhA ftu Attributes esa Character izdkj ds eku gksrs gSa] mUgsa String izdkj ds Variable esa Store fd;k tk ldrk gSA os Attributes tks fdlh izdkj dh Calculation esa Hkkx ugha ysrs gS]a mUgsa Hkh gesa String ;k Character izdkj ds Variable esa Store djuk pkfg,A bl fu;e ds vk/kkj ij ns[ksa rks String dks Store djus okys Attribute dks String Keyword ds lkFk] Character dks Store djus ds fy, char Keyword ds lkFk] Integer izdkj ds eku dks Hold djus okys Attribute ds lkFk int Keyword o Float izdkj ds eku dks Store djus ds fy, float Keyword ds lkFk Attributes dks fy[kus ij gesa fuEukuqlkj Format izkIr gksrk gS% • • • • • •

String String String String float String


tc gess fdlh leL;k ds eq[; Object ds Abstraction ls Abstract Attributes izkIr gksrs gSa] vkSj muesa Store fd, tkus okys ekuksa ds vk/kkj ij ge ;s r; dj ysrs gSa fd fdl Attribute esa fdl izdkj dk eku Store gksxk] vkSj tkok ds vk/kkj ij mu Data Types dks Represent djus okys Keywords dks Abstract Attributes ds lkFk Specify dj nsrs gSa] rks gesa Abstract Attributes dh vc tks Description izkIr gksrh gS] mls tkok Class ds Data Members dgrs gSaA tkok dh fdlh Hkh Class dks gesa”kk fdlh uk fdlh Real World Object dks ,d u, User Defined Data Type dh rjg Represent djus ds fy, Develop fd;k tkrk gS vkSj fdlh Hkh Real World Object ds dqN Attributes ds lkFk mlds dqN Behaviors Hkh gksrs gSa] blfy, tkok dh ml Account Class esa fofHkUu Abstract Attributes dks Represent djus okys Data Members ds lkFk mu Behaviors dks Hkh Specify djuk gksrk gS] tks leL;k ls lEcaf/kr Operations Perform djds bu Data Members ds ekuksa esa ifjorZu djrs gSaA 67 Any Question or Suggestion, Just Discuss Here...

Java in Hindi ;kuh Account Object dks tkok esa rHkh iwjh rjg ls Represent fd;k tk ldrk gS] tc bu Data Account ds Abstract Attributes dks Represent djus okys Data Members ds lkFk Account Object ds Behaviors ;kuh Deposit o Withdraw Operations dks Hkh Specify fd;k tk,A lkekU;r;k Abstract Attributes esa ifjorZu djus okys Operations dks tkok esa Methods dgrs gSaA vr% tc rd ge leL;k ls lEcaf/kr Data Members o Methods dks ,d lkFk ,d Group ds :i esa Specify ugha djsaxs] rc rd tkok fdlh Real World Object dks iwjh rjg ls Logically Represent ugha dj ldsxkA blfy, gesa Account Object ds Abstract Data Members (Attributes) o Methods (Behaviors) nksuksa dks fuEukuqlkj ,d Unit ds :i esa Specify djuk gksxk% Abstract Data Type or Class

//Data Members or Abstract Attributes String Branch Name String Branch Number String Account Number String Account Head Name float Money String Date // Methods or Behaviors Deposit Withdraw

tc gesa tkok esa fdlh Object ds Behavior dks Represent djuk gksrk gS] rc gesa Behavior ;kuh Method ds uke ds lkFk Parenthesis dk iz;ksx djuk gksrk gSA lkFk gh ;s Hkh crkuk gksrk gS fd Method fdlh izdkj dk dksbZ eku Return djsxk ;k ughaA pwafd ge ;gka ij Method dks fcYdqy Simple j[kuk pkgrs gSa] blfy, ge ;s eku jgs gSa fd Method fdlh Hkh rjg dk dksbZ eku Return ugha djsxkA tc ge Method ls fdlh rjg dk dksbZ eku Return djokuk ugha pkgrs gSa] rc tkok Compiler dks bl ckr dh Information nsus ds fy, Method ds uke ds vkxs void fy[krs gSaA tc gesa tkok dh Coding ds :i esa fdlh Object ls lEcaf/kr Abstracted Attributes ;kuh Data Members o Behaviors ;kuh Methods dks ,d Group ;k ,d Single Unit ds :i esa Specify djuk gksrk gS] rc Object ds fofHkUu Data Members o Methods dks Opening o Closing Curly Braces { } ds chp esa Specify djuk gksrk gSA mijksDr nksuksa fu;eksa dks Account Class ds Code Segment ij Apply djus ij gesa Account Object dh Class dk fuEukuqlkj Specification izkIr gksrk gS% // Account Abstract Data Type or Class class Account { // Data Members or Abstract Attributes String Branch Name ;


Java in Hindi String String String float String

}

Branch Number ; Account Number ; Account Head Name ; Money ; Date ;

// Methods or Behaviors void Deposit() void Withdraw()

fdlh Object dks Represent djus okys Data Members o Methods dks ,d Unit ds :i esa Specify djus dh izfØ;k dks OOPS Concept ds vUrxZr Encapsulation uke fn;k x;k gSA ;kuh tc ge Account Object ds Data Members o Methods dks Opening o Closing Curly Braces ds chp esa Specify djrs gSa] rks okLro esa ge Account Object dks Encapsulate dj jgs gksrs gSaA ;kuh geus Account Object dks mijksDr Code Statement }kjk Encapsulated dj fn;k gSA vc bl Code Segment dh “kq:vkr esa class Keyword ds lkFk esa ge Account “kCn Specify dj nsa] rks bldk eryc ;s gS fd geus Account Class cuk nh gS] ftlds Objects dks tkok dk Compiler igpkurk gSA tkok ds lHkh Code Statements ds vUr dks fu/kkZfjr djus ds fy, ;kuh tkok ds Compiler dks ;s crkus ds fy, fd CPU dks fn;k tkus okyk ,d Instruction iwjk gks x;k gS] gesa gj Statement ds ckn esa Semicolon dk iz;ksx djuk gksrk gSA gkykafd vHkh ;s Class v/kwjh gS] D;ksafd geus tkok Compiler dks vHkh ;s ugha crk;k gS fd Deposit() o Withdraw() Methods Account Class ds fofHkUu Data Members dks fdl izdkj ls Change djsaxsA tc gesa Methods dks ;s crkuk gksrk gS fd os fdlh Class ds fofHkUu Data Members ds ekuksa dks fdl izdkj ls Change djsaxs] rc gesa fofHkUu izdkj ds Java Codes fy[kus iMrs gSaA bu fofHkUu izdkj ds Java Codes dks Method ds Parenthesis ds ckn Opening o Closing Curly Braces { } ds chp esa fy[kuk gksrk gSA bu rhuksa fu;eksa dks Apply djus ij gesa Account Object dh Class dk fuEukuqlkj Specification izkIr gksrk gS] tks ,d Real World Account Object dks Computer esa Logically Represent djrk gS% // Account Abstract Data Type or Class class Account { //Data Members or Abstract Attributes String Branch Name ; String Branch Number ; String Account Number ; String Account Head Name ; float Money ; String Date ;


Java in Hindi //Methods or Behaviors void Deposit() { // Java Codes for changing the states of // Data Members based on requirement. }

}

void Withdraw() { // Java Codes for changing the states of // Data Members based on requirement. }

vHkh Hkh bl Class ds Objects Create ugha fd, tk ldrs gSaA D;ksafd tkok esa fofHkUu izdkj ds ekuksa dks Store djus ds fy, ftu Variables dks Declare djrs gSa] mu Variables ds uke nsus ds dqN fu;e gSaA ;fn ge mu esa fdlh Hkh fu;e dks Neglect djrs gSa] rks Java Compiler Program esa Compile Time Error Generate djrk gSA

Identifier Naming System

Computer esa fofHkUu izdkj ds ekuksa dks Store djus ds fy, Data ds vuqlkj Memory esa dqN txg Reserve dh tkrh gS vkSj ml Reserved txg dks igpkuus ds fy, Programmer ml txg dks dksbZ uke nsrk gSA tSls ;fn Programmer fdlh O;fDr dh Age Computer esa Store djuk pkgrs gSa] rks Age Store djus ds fy, mls Integer izdkj dk ,d Identifier Create djuk gksxk ;kuh eku dks Store djus ds fy, Memory esa dqN txg Reserve djuh gksxh vkSj ml Reserved Memory dks ,d uke nsuk gksxkA bl uke ls gh ml Memory Location dks igpkuk tk ldrk gS ftl ij Programmer us Age ds eku dks Store fd;k gSA tkok esa fdlh Identifier dks uke nsus ds dqN fu;e gSa] tks fuEukuqlkj gSa% •

• • • •

Identifier ds uke esa A to Z Capital o Small Letters dk iz;ksx fdlh Hkh izdkj ls fd;k tk ldrk gSA Underscore dk iz;ksx fd;k tk ldrk gSA ;fn uke esa fdlh Digit dk iz;ksx djuk gks] rks uke ds vUr esa Digit dk iz;ksx fd;k tk ldrk gSA uke esa fdlh Operator, Special Symbol ;k Keyword dk iz;ksx ugha fd;k tk ldrk gSA uke esa Blank Space dk iz;ksx ugha fd;k tk ldrk gS] D;ksafd Blank Space ,d rjg dk Special Symbol gSA

geus gekjh Specification esa Abstract Attributes dks Represent djus okys T;knkrj Data Members ds uke ds chp esa Whitespace dk iz;ksx fd;k gSA blfy, tkok bu Identifiers dks Accept ugha djrk gS vkSj gesa Errors nsrk gSA tkok dk ,d Naming Convention gS] ftlesa tc gesa fdlh Class dk uke nsuk gksrk gS vkSj uke esa nks ;k vf/kd “kCn gksrs gSa rc gesa fuEukuqlkj uke nsuk pkfg,%


Java in Hindi PopulationOfIndia, AgeOfMoon, BasicSalary

blh rjg ls tc gesa fofHkUu Data Members dk uke nsuk gksrk gS vkSj uke esa ,d ls T;knk “kCn gksa rks mUgsa fuEukuqlkj uke nsuk pkfg,% populationOfIndia, ageOfMoon, basicSalary

vc pwafd geus gekjs Description esa fofHkUu Data Members ds chp Space dk iz;ksx fd;k gS] blfy, ;fn bl Class dks Bhd izdkj ls Specify djuk gS rks gesa bl Class dks fuEukuqlkj Modify djuk iMsxkA // Account Abstract Data Type or Class class Account { //Data Members or Abstract Attributes String branchName ; String branchNumber ; String accountNumber ; String accountHeadName ; float money ; String date ; //Methods or Behaviors void Deposit() { // Java Codes for changing the states of // Data Members based on requirement. }

}

void Withdraw() { // Java Codes for changing the states of // Data Members based on requirement. }

gkykafd geus Deposit() o Withdraw() Method esa fdlh rjg ds Code ugha fy[ks gSa] blfy, bl Class ds Object fdlh Hkh rjg dk dksbZ Hkh dke ugha djsaxsA fQj Hkh ;s Class iwjh rjg ls Executable gS vkSj ge bl Class ds Objects Create dj ldrs gSaA bl rjg ls ge fdlh leL;k ls lEcaf/kr fdlh t:jh Object dks ,d Abstract Data Type (Class) ds :i esa Specify djds Object dks Computer esa Logically Represent dj ldrs gSaA ,d ckj fdlh leL;k ds vk/kkj ij fdlh Object dh Class cuk nsus ds ckn ge ml Class ds ftrus pkgsa mrus Objects Create dj ldrs gSaA ;kuh mijksDr Account Class ds vk/kkj ij ge ftrus pkgsa mrus Customers ds Account dks Computer esa mlh rjg ls Logically Create o Manage dj ldrs gSa] ftl rjg ls Real World esa yksxksa ds Account dks Physically Create o Manage fd;k tkrk gSA


Java in Hindi Java – Graphical User Interface and Graphics Management

Computer esa GUI o Graphics Management dks Hkh ge ,d leL;k ds :i esa ns[k ldrs gSaA fofHkUu izdkj ds User Interface Components (Button, Scrollbars, Menu Bars, Status Bars, Dialog Boxes, Radio Buttons, Check Boxes, Text Fields) dks Create djus o mUgsa Computer esa Bhd rjg ls Manage djus ds fy, Hkh fofHkUu izdkj dh Graphics Classes dks igys ls gh Develop djds tkok ds Compiler ds lkFk gesa iznku fd;k tkrk gSA

bu fofHkUu izdkj dh Graphics Classes dks tkok esa Abstract Windowing Toolkit (AWT) uke ds ,d Package esa Store djds j[kk x;k gSA pwafd tkok OOPS dks iwjh rjg ls Support djrk gS] blfy, ge blesa Inheritance dh lqfo/kk dks iwjh rjg ls izkIr dj ikrs gSaA Inheritance OOPS dk ,d ,slk Concept gS] ftlds vk/kkj ij ge fofHkUu izdkj dh Classes cuk dj mUgsa muds Group ds vk/kkj ij fofHkUu izdkj ds Packages esa Store dj ldrs gSa vkSj t:jr gksus ij mu Classes ds Codes dks T;ksa dk R;ksa izkIr Hkh dj ldrs gSa vkSj muesa Modification djds viuh t:jr ds vuqlkj ubZ Classes Hkh cuk ldrs gSa] ftuesa mudh iqjkuh Classes ds lHkh Features ekStwn gksrs gSaA

bldk eryc ;s gqvk fd vius Program dks Graphics Mode esa Develop djus ds fy, ;s t:jh ugha gS fd ge fofHkUu izdkj ds Graphical Components dks fQj ls Develop djsa vkSj muds fy, fQj ls fofHkUu izdkj dh Classes Create djsa] cfYd ge AWT Package esa miyC/k fofHkUu izdkj dh Classes dks Inherit djds fQj ls Reuse dj ldrs gSa vkSj vius Program dks Graphical Mode esa Develop dj ldrs gSaA

Web Page – The Part of Website

tSlkfd geus igys Hkh dgk gS fd Applet os NksVs Programs gksrs gSa tks fdlh Web Page dks vf/kd Interactive cukus ds fy, Develop fd, tkrs gSaA Applet dks le>us ls igys ge ;s le>rs gSa fd vkf[kj Web Pages D;k gSa vkSj budh t:jr D;k gSA Web Pages ,sls Electronic Pages gSa] ftu ij Stored Information nqfu;ka esa dgha Hkh ns[kh tk ldrh gSaA Web Pages lwpukvksa dks rsth ls lkjh nqfu;ka esa QSykus dk lcls vPNk ek/;e gS] fQj pkgs ;s lwpuk fdlh University dk Declare fd;k x;k Result gks ;k fdlh Company ds

fdlh u, mRikn ds ckjs esa fn;k x;k foKkiu A

lkekU;r;k Web Pages dk T;knkrj mi;ksx fofHkUu izdkj dh Companies vius mRikn dh Advertisement djus ds fy, djrh gSa] rkfd muds mRikn dks lkjh nqfu;ka tku lds vkSj mudk O;olk; National ls c ikrs gSaA blh


Java in Hindi Concept ds vk/kkj ij ;s ekuk x;k fd ;fn Web Pages Hkh Multimedia ls ;qDr gksa] rks T;knk ls T;knk yksx Web Pages dks ns[ksaxs vkSj fdlh Company ds mRikn dk T;knk ls T;knk yksxksa esa foKkiu gks ldsxkA

blfy, ,sls Web Pages cukus dh t:jr eglwl dh xbZ] ftlesa Multimedia ;kuh Sound, Video, Animation, Graphics vkfn dk T;knk ls T;knk iz;ksx fd;k x;k gks vkSj fdlh Web Page esa Multimedia dks ykus ds fy, tkok Applets lcls vPNk lk/ku gSaA blds lkFk gh vkt tks O;olk; fd, tkrs gSa os fdlh ,d “kgj ;k ,d ns”k rd lhfer ugha gksrs gSaA fofHkUu izdkj dh Multinational Companies vkil esa fey dj O;olk; djrh gSaA ,sls esa fdlh Multinational Company ds fofHkUu Hkkxhnkjksa dks dHkh Hkh viuh Company dh Financial fLFkfr tkuus dh t:jr iM ldrh gSA ,sls esa gj Hkkxhnkj viuh Company dh fLFkfr tkuus ds fy, Center Office ls tkudkjh izkIr dj lds] ;s O;oLFkk Bhd ugha dgh tk ldrhA D;ksafd gks ldrk gS fd Company dk dksbZ Partner India esa jgrk gks vkSj Company dk Center Office America esa gksA ,sls esa India dk og O;fDr ;s dSls tku ldsxk fd mldh Company dh fLFkfr D;k gS] ftlesa mlus viuk /ku Invest fd;k gSA bl izdkj dh fLFkfr esa Company ls lEcaf/kr lHkh lwpukvksa dks America ds Center Office esa ;fn gj jkst Web Pages ds :i esa Internet ij Mky fn;k tk,] rks India dk og Partner Hkh Company dh fLFkfr dks gj jkst fdlh Hkh le; tku ldrk gSA pwafd Company dh orZeku fLFkfr dh fofHkUu izdkj dh lwpukvksa dks Analyze djds fofHkUu izdkj ds Decisions ysus gksrs gSa] blfy, fofHkUu izdkj dh Information dks fofHkUu izdkj ds Graphs, Charts vkfn ds :i esa O;ofLFkr fd;k tkrk gS] rkfd fofHkUu izdkj ds t:jh Decisions rqjUr fy, tk ldsaA bu fofHkUu izdkj ds Graphics o Charts vkfn dks fofHkUu izdkj ds User }kjk fn, tkus okys Data ds vk/kkj ij Online Develop gks ldsa] blds fy, ,sls Interactive Web Pages dh t:jr gksrh gSa] tks User ds lkFk FkksMk cgqr Interaction dj ldsa vkSj ;s lqfo/kk dsoy Applets }kjk gh izkIr dh tk ldrh gSa] D;ksafd tkok Applets os Programs gksrs gSa] tks Web Pages esa Run gksrs gSa vkSj Web Pages iwjh nqfu;ka esa dgha ls Hkh Access fd, tk ldrs gSaA bu Web Pages ij User }kjk Parameter ds :i esa Specify fd, x, Inputs dks Applets Accept dj ldrs gSa vkSj fofHkUu izdkj ls Modify gksdj User dh lkekU; t:jrksa dks Online ;kuh Run Time esa iwjh dj ldrs gSaA lkjka”k ;s gqvk fd Applets dk iz;ksx Web Pages esa djuk gksrk gS] blfy, Applet Programming djus ls igys gesa Web Page cukuk lh[kuk gksxkA Web Site ,d ,slh Book dh rjg gksrh gS] ftlesa cgqr lkjs ,sls Electronic Pages gksrs gSa] ftuesa lwpukvksa dks Present djus ds fy, fofHkUu izdkj ds Multimedia dk iz;ksx fd;k tkrk gSA Web Pages Develop djus ds fy, gesa fdlh fo”ks’k Compiler ;k Software dh t:jr ugha gksrh gS uk gh Web Pages ds Output dks ns[kus ds fy, ;s t:jh gksrk gS fd ge Internet ls Connected gksaA


Java in Hindi ge fdlh Web Site ds fofHkUu Pages dks Notepad esa Develop dj ldrs gSa] vkSj mls Internet Explorer ;k ,sls gh fdlh Browser esa Embed djds ;kuh Run djds ns[k ldrs gSa fd ;s Web Pages Internet ij Run gksus ij fdl izdkj ds fn[kkbZ nsaxsA Web Pages Develop djus ds fy, dqN Basic rS;kfj;ka djuh gksrh gSaA ;kuh gesa ;s r; djuk gksrk gS fd ge Web Pages dks fdu yksxksa ds fy, Develop dj jgs gSa vkSj mu yksxksa dks Web Pages }kjk D;k tkudkjh nsuk pkgrs gSaA ge tks tkudkjh nsuk pkgrs gSa] mlds Contents dks iwjh rjg ls Develop djus ds ckn gesa mu Contents dks Web Pages ds :i esa Represent djuk gksrk gSA

vius Contents dks Web Pages esa Represent djus ds fy, gesa HTML (Hyper Text Markup Language) Tags dk iz;ksx djuk gksrk gSA HTML Tags ,sls Tags gksrs gSa] ftUgsa lHkh Computers Platforms leku :i ls Support djrs gSa] blfy, ge ftl Web Site dks Develop djds Internet ds Web Server ij Store dj nsrs gSa] og Web Site fofHkUu izdkj ds Hardware o Platform dks Use djus okys lHkh yksxksa dks leku :i ls fn[kkbZ nsrh gSA HTML Pages cukus ds fy, gesa HTML ds fofHkUu Tags dks ,d Notepad esa fy[kuk gksrk gS vkSj ml Notepad dh File dks .HTML uke ls Save djuk gksrk gSA tc ge fdlh Notepad esa Create dh xbZ File dks .HTML Extension ls Save djrs gSa] rc og File Internet Explorer ;kuh fdlh Web Browser esa Open gksus okyh File cu tkrh gSA ge Windows Platform ij dke dj jgs gSa] blfy, ge gekjh lHkh Files, Internet Explorer esa Open gksxhA

HTML Tags for Web Pages

HTML File cukus ds fy, gesa tks Tabs fy[kus gksrs gSa] os Tabs Hkh dqN fo”ks’k rjhds ls fy[kus gksrs gSaA ,d Web Page esa Contents o Tags ;kuh dqy nks phtsa gksrh gSaA Tags os Commands gksrs gSa ftUgsa Web Browser le>rk gS vkSj muds vk/kkj ij fn, x, Contents dks fofHkUu izdkj ds Web Pages ij Display djrk gSA fofHkUu izdkj ds HTML Tabs dks Opening o Closing Bracket ( < > ) ds chp fy[kk tkrk gSA

lkFk gh fofHkUu izdkj ds Contents dks < > o ds chp fy[kk tkrk gSA “ / ” dk fpUg ,d Tag ds vUr dks n”kkZrk gSA ,d Web Page ds fofHkUu Tags o Contents dks o Tags ds chp fy[kk tkrk gSA fdlh Hkh Web Page ds eq[;r% rhu Hkkx gksrs gSa% Comment Section ;s ,d Optional Section gSA ge pkgsa rks bls fcuk Specify fd, gq, Hkh Web Page Develop dj ldrs gSaA Comments fdlh Web Page ds ckjs esa General tkudkjh nsrs gSaA Comment nsus ds fy, ds chp Statement fy[kk tkrk gSA bl rjg ds Bracket esa tks Text fy[ks tkrs gSa] os Browser esa fn[kkbZ ugha nsrs gSaA ;s Comment gesa fuEukuqlkj fy[kuk gksrk gS%

gkykafd Comment Text Web Pages esa Front esa fn[kkbZ ugha nsrs gSa] ysfdu fQj Hkh ;s Web Pages ds lkFk Client ds Computer esa Download rks gksrs gh gSa] blfy, gesa gekjs Web 74 Any Question or Suggestion, Just Discuss Here...

Java in Hindi Page esa de ls de Comment fy[kus pkfg,aA gkykafd ge Web Page esa dgha Hkh vkSj fdruh Hkh ckj Comment fy[k ldrs gSaA

Head Section ;s Hkh ,d Optional Section gSA ge pkgsa rks bls Hkh fcuk Specify fd, Web Page Develop dj ldrs gSaA Head Section dks o Tag }kjk Define fd;k tkrk gSA bl Tag dk iz;ksx Web Page dk uke ;kuh Title nsus ds fy, fd;k tkrk gSA bl Section esa o ds chp esa ge tks Text fy[k nsrs gSa] og Text Web Page ds Title Bar esa fn[kkbZ nsus yxrk gSA Web Page esa fn[kkbZ nsus okys Title dks fuEukuqlkj Tags }kjk Define fd;k tk ldrk gS% Betalab Computer Center

Body Section ;s Hkh ,d Optional Section gSA Head Section ds ckn esa Body Section vkrk gS] tgka ge Web Page ds Contents fy[krs gSa vkSj fofHkUu izdkj ds Multimedia dk iz;ksx Hkh ;gha ij djuk gksrk gSA mUgsa fofHkUu rjhdksa ls Web Page ij n”kkZ ldrs gSaA

Adding Applet in HTML File

ftl rjg ls ge fofHkUu izdkj ds Tags dk iz;ksx djds fofHkUu izdkj ls fdlh Web Page dks Design djrs gSa] mlh rjg ls fdlh Applet dks HTML Page esa Embed djus ds fy, gesa Tag dk iz;ksx djuk iMrk gSA bl Tag esa gesa ;s Specify djuk gksrk gS fd Web Page esa Embed fd, tkus okys Applet dk uke D;k gS vkSj ml APPLET dh Web Page esa Size D;k gksxhA ;fn gesa fdlh HellJava uke ds Applet dks Web Page esa Embed djuk gks] rks gesa fuEukuqlkj APPLET Tag Code fy[kuk gksrk gS% Betalab Computer Center Welcome to the world of Java.


Java in Hindi

Applet Architecture – The Event Based GUI Application Program

fdlh Applet dks ,d Web Page esa fdl Code }kjk Embed fd;k tk ldrk gS vkSj Web Page dks Java Applet dk iz;ksx djds fdl izdkj ls vf/kd Interactive cuk;k tk ldrk gS] bl lEca/k esa FkksMh Basic tkudkjh ysus ds ckn vc ge ;s le>saxs fd Applets dks dSls Develop fd;k tkrk gSA lkFk gh ge ;s Hkh tkusaxs fd Applets fdl izdkj ls dke djrs gSa vkSj fdl izdkj ls Define fd, tkrs gSaA ;kuh ge Applets ds Architecture dks le>saxsA Applet ds lEca/k esa lcls igyh ckr ;s gS fd Applet ,d Window-Based Event Driven Program gksrk gSA Event Driven Programming ds ckjs esa ge blh v/;k; esa vkxs le>saxsA pwafd Applet ,d Event Driven Window-Based Program gksrk gS] blfy, bldk Architecture fdlh vU; Normal Console-Based Program ls vyx gksrk gSA

blfy, Applets Develop djus ls igys gesa ;s tkuuk t:jh gS fd Applets fdl izdkj ls dke djrs gSa vkSj fdl izdkj ls bUgsa Design fd;k tkrk gSA Applets fofHkUu izdkj ds Interrupts Service Routines dks Handle djus okys Code Segments ;k Methods ds Implementation ij vk/kkfjr gksrs gSaA GUI Applications esa Mouse ;k Keyboard ls dqN Hkh djuk Event dgykrk gSA ;kuh Mouse ls Click djuk ;k Keyboard ls Key Press djuk] bu nksuksa fLFkfr;ksa esa dqN Events Generate gksrs gS]a ftuds ckjs esa ge vkxs foLrkj ls le>saxsA

gekjk Applet bUgha Events dk bUrtkj djrk jgrk gSA tSls gh dksbZ Event Generate gksrk gS] AWT Package Applet }kjk iznku fd, x, fdlh ,d Event Handler Method dks Call djrk gS vkSj Generate gksus okys Event ds lEca/k esa tkudkjh ns nsrk gS ;k Notify dj nsrk gSA ,d ckj ,slk gks tkus ds ckn Appropriate Action ysus vkSj Control dks okil AWT esa Pass djus dh ftEesnkjh Applet dh gksrh gSA ge fdlh Applet ij tSls gh fdlh Mouse Button ls Click djrs gSa] ,d Mouse Event Generate gksrk gS] ftls Applet esa Define fd;k x;k Handler Respond djrk gSA blh rjg ls ;fn Keyboard ls dksbZ Key Press dh tkrh gS] rks Hkh ,d Event Generate gksrk gS] ftls Applet dk dksbZ Handler Respond djrk gSA fdlh Applet ls lEcaf/kr ftrus Hkh Basic ;k Primary Initializations o Functionality gSa] mUgsa Applet uke dh Class esa Define fd;k x;k gSA Applet uke dh ;s Class applet uke ds Package esa miyC/k gSA pwafd tkok OOPS ds Concepts dks Implement djrk gS vkSj ,d iw.kZ Object Oriented Programming Language gS] blfy, ge blesa Inheritance Concept dks iwjh rjg ls Apply dj ldrs gSa vkSj Packages esa Classes ds :i esa Stored fofHkUu izdkj ds igys ls Define fd, x, Codes dks T;ksa dk R;ksa Reuse dj ldrs gSaA 76 Any Question or Suggestion, Just Discuss Here...

Java in Hindi blfy, Applet Class dks Inherit djds ge ,d Applet ls lEcaf/kr fofHkUu Basic Initializations o Functionality dks izkIr dj ldrs gSaA pfy,] vc ge ,d Applet dks Applet Class ls Inherit djds Applet Class dh fofHkUu Properties o Functionality dks izkIr djrs gSa] ;kuh ,d Applet cukrs gSaA Program: MyFirstApplet.java // Inheriting An Applet from Built–In Applet Class import java.awt.*; import java.applet.*; public class MyFirstApplet extends Applet { }

bl Code dks ,d Notepad esa fy[ksa “C:\” Derive esa ,d JAVASOURCE uke dk Folder cuk dj mlesa MyFirstApplet.java uke ls Save djsaA vc Command Prompt ij tkdj fuEu Statement }kjk ml Folder esa igqaps] tgka ij MyFirstApplet.java dks Save fd;k gS] ;kuh JavaSource Folder esa igqapsaA C:\>CD JAVASOURCE

// Press Enter

vc fn[kkbZ nsus okyk Command Prompt fuEukuqlkj gksxk% C:\JAVASOURCE>

vc Source File dks Compile djus ds fy, fuEu Command Type djsa% C:\JAVASOURCE>javac MyFirstApplet.java

// Press Enter

tc fcuk fdlh Error ds File Compile gks tk,xh] rc JAVASOURCE Folder esa ,d ubZ File cusxh ftldk Extension .class gksxkA ;kuh gekjh Source File Compile gksus ds ckn MyFirstApplet.class uke dh ,d Class File cusxh ;s File ,d Executable File gksrh gS] ftls fdlh Hkh Platform esa fdlh Hkh Browser }kjk ,d Web Page esa Embed djds Run fd;k tk ldrk gSA bl Applet dks Test djus ds fy, gesa ,d Web Page cukuk gksxkA Web Page cukus ds fy, ,d Notepad esa fuEu HTML APPLET Tag fy[k dj mlesa MyFirstApplet.class Filed dks Embed dj ldrs gSaA My First Applet


Java in Hindi Welcome to the world of Java.
Notepad esa ;s HTML Tabs fy[kus ds ckn File dks mlh Folder esa Save djuk gksrk gS] tgka ij Java Applet dh Class File Stored gSA ge ;s eku jgs gSa fd gekjh Source File o mldh Class File nksuksa gh “C:\JAVASOURCE” esa Stored gSaA blfy, bl HTML File dks Hkh gesa ;gha ij Store djuk gksxkA

;fn gekjk Browser Java dks Support djrk gS ;k Java Enabled gS] rks ge Create gksus okys MyFirstApplet.HTML Web Page dks Open djds Applet dks Web Page esa ns[k ldrs gSaA Netscape Navigator ,d Java Enabled Web Browser gS] ftlesa ge fdlh Hkh Web Page esa Contained Applet dks Directly ns[k ldrs gSaA ;kuh ;fn ge MyFirstApplet.HTML File dks Open djsa] rks gesa ;s File fuEukuqlkj fn[kkbZ nsxh%

;fn gekjk Browser Java Enabled ugha gSa] rks gesa tkok ds lkFk vkus okys Appletviewer dk iz;ksx djds gesa vius Applet dks Test djuk gksrk gSA Appletviewer dk iz;ksx djds Applet dks Test djus ds fy, MyFirstApplet.HTML File Create djus ds ckn Command Prompt ij fuEukuqlkj Command fy[kuk gksrk gS% C:\JAVASOURCE>Appletviewer MyFirstApplet

// Press Enter

tc ;s Command fy[kdj Enter Key Press djrs gSa] rks gesa Output esa fuEukuqlkj Applet Viewer fn[kkbZ nsrk gSA


Java in Hindi

pfy,] vc ge bl Applet dh Coding dks le>us dh dksf”k”k djrs gSaA dksbZ Hkh Applet Create djus ds fy, gesa tkok esa igys ls Define dh xbZ Applet Class ds xq.kksa dks Inherit djus ds fy, ,d Sub Class cukuh iMrh gS vkSj igys ls cuh gqbZ Applet Class ds lHkh xq.kksa o Functionality dks Derive djuk iMrk gSA tkok fdlh esa Class dks Inherit djus ds fy, extends Keyword dk iz;ksx djuk gksrk gSA ;kuh tc ge viuh dksbZ Applet Class cukuk pkgrs gSa] rc gesa gekjh Applet Class dks tkok dh Applet Class ls Inherit djuk iMrk gS] rkfd ge gekjh Class esa fdlh Applet ls lEcaf/kr fofHkUu izdkj dh Properties o Functionality dks T;ksa dk R;ksa izkIr dj ldsa vkSj fcuk fdlh izdkj ds fo”ks’k Overhead ds ,d Applet Create dj ldsaA extends Keyword dk iz;ksx blfy, fd;k x;k gS] D;ksafd tkok esa Applet ls lEcaf/kr tks Built–In lqfo/kk,a iznku djrk gS] ge mu lqfo/kkvksa dks rks T;ksa dk R;ksa Use dj ysrs gSa] lkFk gh Create gksus okyh Sub Class esa viuh vko”;drkuqlkj u, Features Hkh Add dj ldrs gSaA geus gekjh Coding esa fuEu Statement }kjk tkok dh Applet Class dks Inherit fd;k gS% public class MyFirstApplet extends Applet { }

bl Statement esa geus tkok Compiler dks crk;k gS fd ,d ubZ Class cuk jgs gSa] ftldk uke MyFirstApplet gS ,d Access Specifier gS] tks ;s crkrk gS fd bl Class esa Create fd;k tk ldrk gSA Access Specifies ds ckjs

ge Applet Class dks Extend djds vkSj ;s ,d Public Class gSA Public ds Objects dks fdlh Hkh vU; Class esa ge vkxs foLrkj ls ppkZ djsaxsA

ge tc Hkh dksbZ Applet Extend djrs gSa] rks Create gksus okys fdlh Hkh Applet dh Lifetime ds eq[;&eq[; pkj Events gksrs gSa vkSj gj Event ls Applet Class dk ,d Method Associated jgrk gSA fdlh Applet dh Life Cycle ds pkjksa Steps dks ge pkj Methods }kjk Represent dj ldrs gSa% public void init() Method tc User fdlh ,sls Web Page dks Open djrk gS] ftlesa Applet Embed gksrk gS] rks Web Page ds Memory esa Load gksrs gh Applet dqN izkjfEHkd ekuksa ls Initialize gksrk gSA Applet ds ;s izkjfEHkd eku Applet Class ds init() Method }kjk Initialize gksrs gSaA ;fn ge Applet ds Initialization ds le; fdUgha Variables dks dksbZ eku iznku djuk pkgsa] ;k dqN ,sls dke djuk pkgsa] tks Applet ds Initialize gksrs gh Execute djus gksa] tSls fd fofHkUu izdkj ds GUI Objects dks Applet ij Add djuk gks] rks bu dkeksa dks djus ds Codes gesa


Java in Hindi init() Method esa fy[kus gksrs gSaA ;s Method fdlh Applet dh Life esa dsoy ,d gh ckj Execute gksrk gSA

;fn nqckjk init() Method dks Execute djuk gks] rks gesa Web Page dks Close djds fQj ls Open djuk iMrk gSA public void start() Method init() Method }kjk Applet Initialize gksus ds ckn start() Method Call gksrk gSA lkFk gh ge ftruh Hkh ckj Applet dks Restart djrs gSa] ;s Method Execute gksrk gSA Applets dks ml le; Stop fd;k tk ldrk gS] ftl le; User ,d Web Site ls nwljh Web Site ij Move gksrk gSA ;fn User dqN le; ckn esa fQj ls ml Web Site ij vkrk gS] rks Applet fQj ls Restart gksrk gSA blfy, start() Method dks Applet dh Life Time esa vko”;drkuqlkj dbZ ckj Call fd;k tk ldrk gSA Applet tc Hkh fdlh Event ds dkj.k Focus Receive djrk gS] ;s Method Execute gksrk gSA ge bl Method esa mu Codes dks fy[k ldrs gSa] ftUgsa Applet ds Restart esa Execute djokuk pkgrs gSaA tSls fd Applet esa fdlh Thread dks Initialize djus ds le; ;k Screen ds Data dks Update djrs le; Applet gj ckj ,d Focus izkIr djrk gS ftlls gj ckj Applet Restart gksrk gSA

public void stop() Method ;s Event rc Generate gksrk gS] tc ,d Web Browser fdlh HTML Page dks NksM dj fdlh nwljs Web Page ij tkrk gS] ;k Web Page ij ls Focus Lost gksrk gSA ge bl Method dks rc Use dj ldrs gSa tc ge Program ds fofHkUu Variables dks Reset djuk pkgrs gSa ;k fdlh Running Thread dks Stop djuk pkgrs gSaA public void destroy() Method tc Applet iwjh rjg ls Execute gksuk cUn gks tkrk gS ;k tc User ,d Page ls nwljs Page ij Move gks tkrk gS] rc ;s Method Execute gksrk gSA ge bl Method dk iz;ksx fdlh Applet }kjk Use gks jgs fdlh Resource dks Free Up djus ds fy, dj ldrs gSaA stop() Method gesa”kk destroy() Method ls igys Call gksrk gSA ;s pkjksa gh Methods Automatically Call gksrs gSa vkSj ge bUgsa fdlh Hkh izdkj ls vyx ls Call ugha djrs gSaA Applet esa tks dqN Hkh Display gksrk gS] mls Display djus ds fy, gesa paint() Method dks Use djuk gksrk gSA bl Method ds fcuk ge Applet esa dqN Hkh Display ugha dj ldrs gSaA bl Method ds vykok nks vU; Methods update() o repaint() Hkh gSa] ftudk iz;ksx vyx&vyx ifjfLFkfr;ksa esa Applet dks Paint djus ds fy, djuk iMrk gSA public void paint() Method tc Hkh gesa Applet Window dks Paint djuk gksrk gS] rc gesa bl Method dks Call djuk iMrk gSA Applet Window dks Paint djus dk eryc ;s gS fd tc Hkh gesa fdlh Information OR Graphics dks Applet esa Display djuk gksrk gS] rks ml Information ;k Graphics dks Applet


Java in Hindi dh Window esa Draw dj nsrs gSaA Information ;k Graphics dks Window esa Display djus dh izfØ;k dks Window Paint djuk dgrs gSaA dqN fLFkfr;ksa esa Paint Method Lo;a gh Automatically Call gks tkrk gSA tSls tc ,d Window Display gks jgk gks vkSj ml Window ij dksbZ nwljk Window Overwrite gks tk, vkSj fQj igys Window dks Activate fd;k tk,] rks gesa nwljk Window fn[kkbZ nsus ls igys Repaint gksrk gSA bls ge fuEu fp= }kjk le> ldrs gSa% bl fp= esa MS Paint ls Media Player Hide gks jgk gSA vc ;fn ge Media Player dks Activate djsa] rks Media Player fQj ls Paint gksrk gS vkSj MS Paint Hide gks tkrk gS] ftls ge fuEu fp= esa ns[k ldrs gSa%

blh rjg ls tc ge fdlh Window dks Minimize ;k Restore djrs gSa] rc Hkh og Window Paint gksrk gSA tc igyh ckj Applet dk Execution “kq: gksrk gS] rc Hkh ;s Method Call gksrk gSA


Java in Hindi dkj.k dksbZ Hkh gks] tc Hkh Window ds Output dks Redraw djuk gksrk gS] ;s Method Call gksrk gSA paint() Method dks repaint() Method dks Call djds Trigger fd;k tk ldrk gSA Applet Class ds paint() Method esa Parameter ds :i esa Graphics Class dk ,d Object Specify djuk gksrk gSA bl Parameter esa ml Graphics Object dh Information gksrh gS] ftls Applet ij Draw djuk gksrk gSA

public void update() Method ;s Method paint() Method dh rjg gh dke djrk gSA bl Method dks Call djus ij ;s Method Screen dks Clear djrk gS vkSj fQj ls paint() Method dks Call djds Screen dks Repaint dj nsrk gSA public void repaint() Method tc ge Applet dks Repaint djuk pkgrs gSa] rc ge repaint() Method dks Call dj ldrs gSaA repaint() Method Automatically update() Method dks Call djds Screen dks Redraw djrk gSA

First Applet in Java

fdlh Applet esa Text dks Display djuk lcls ljy dke gSA ysfdu Applet Window Based GUI dks Support djrk gS vkSj Window esa tks dqN Hkh fn[kkbZ nsrk gS] og lcdqN Graphical Form esa gksrk gS] blfy, tkok ds Graphical Text Function dks Use djds Applet esa String dks Draw djuk iMrk gSA tkok esa String dks Draw djus ds fy, drawString() Method dks Generally Use fd;k tkrk gSA ;s Method awt Package esa fLFkr Graphics Class dk ,d fgLlk gSA Package dqN lEcaf/kr izdkj dh Classes ds Collection ds vykok vkSj dqN ugha gksrk gSA fuEu Code Segment ,d Applet dk gS] ftlesa ,d String dks Display djok;k x;k gSA import java.awt.*; import java.applet.*; public class DrawStringApplet extends Applet { public void paint(Graphics firstString) { firstString.drawString("First String in Java Applet ", 10, 25); } } Output:


Java in Hindi

bl Program esa lcls igys awt o applet Package dks Use djus ds fy, Import fd;k x;k gSA Import Statement ds dkj.k ge Applet Class ds lHkh Features dks DrawStringApplet uke dh ubZ Class esa Derive ;k Inherit djus dh lqfo/kk izkIr djrs gSaA tc ge Applet Class dks Derive djds mlds Features dks DrawStringApplet Class esa izkIr djrs gSa] rks ge blh Class esa Applet Class ds fofHkUu Methods dks Hkh izkIr djrs gSaA paint() Method Hkh Applet Class dk gh ,d Method gSA ;s Method gesa Applet Class dks Derive djus ls izkIr gksrk gSA bl Method dks Override djds ge Applet ij String dks Draw dj ldrs gSaA String dks Draw djus ds fy, Graphics Class dk drawString() Method Execute fd;k x;k gSA

public abstract void drawString(String text, int x, int y)

bl Program esa geus Applet Class ds drawString() Method }kjk ,d String dks Applet ij x o y dh Location ij Display fd;k gSA gesa ftl String dks Screen ij Display djuk gksrk gS] mls bl Method esa igys Argument ds :i esa fy[kuk gksrk gSA nwljk o rhljk Argument ,d Number gksrk gS] tks Applet ij String dh Display gksus dh Location dks Specify djrs gSaA Flow of This Applet

ge tkurs gSa fd tc Hkh Applet dh Screen dks Draw djuk gksrk gS] rc Applet Class dk paint() Method Execute gksrk gSA tc igyh ckj Applet Screen ij Appear gksrk gS] rc paint() Method igyh ckj Execute gksrk gSA bl Program esa tc ge Web Page Run djrs gSa vkSj Applet Appear gksrk gS] rc Applet ds Appear gksrs gh tkok paint() Method dks Call djrk gS vkSj paint() Method drawString() Method dks Call djrk gS] tks fd String dks Applet ij Display dj nsrk gSA paint() Method Graphics Class dk Method gSA ;s Method fdlh Graphics Object dks Applet esa Display djus dk dke djrk gSA bl Program esa ge ns[k ldrs gSa blds Parenthesis esa firstString uke dk ,d Object Pass fd;k x;k gSA

bldk eryc ;s gS fd tkok paint() Method esa Graphics Class dk ,d Object Argument ds :i esa Hkst jgk gS] ftldk uke firstString gSA pwafd firstString Graphics Class dk ,d Object gSA blfy, ;fn ge bl Object dks Display djuk pkgrs gSa] rks gesa Graphics Class ds gh fdlh ,sls Method dks Call djuk gksxk] tks gekjh t:jr dks iwjk dj nsA


Java in Hindi pwafd ge ,d String dks Display djuk pkgrs gSa] blfy, gesa firstString Object ds fy, drawString() Method dks Call djuk gksxkA tc gesa fdlh Object ds fy, fdlh Method dks Call djuk gksrk gS] rc gesa ml Object dks Dot dk iz;ksx djds Method ls tksMrs gq, Call djuk iMrk gS] rkfd Call gksus okyk Method mlh Object ij izfØ;k djs] ftlds lkFk mls Call fd;k x;k gSA blhfy, geus gekjs Program esa fuEu Code Line fy[kh gS% firstString.drawString("First String in Java Applet ", 10, 25);

;s Statement tkok Compiler dks firstString Object ds drawString() Method dks Call djus ds fy, Message nsrk gSA drawString() Method ds Parenthesis esa iznku fd;k tkus okyk eku Argument dgykrk gSA ;s os eku gksrs gSa] ftUgsa Method esa Information ds :i esa Pass djuk gksrk gSA drawString() Method ds Arguments tkok Compiler dks “First String in Java Applet” String dks Column Number 10 o Row Number 25 ij Display djus ds fy, Instruction nsrk gSA Row o Columns dks Pixels esa Measure fd;k tkrk gS uk fd Characters esaA Pixel fdlh Screen ij fn[kkbZ nsus okyk lcls NksVk Dot gksrk gSA Display gksus okys Text dks vyx Location ij Display djuk gks] rks gesa Row o Column dh la[;k Change djuh gksrh gSA

GUI – The Event Driven Programming System ekuyks fd ge lqcg&lqcg tSls gh Office tkus ds fy, ?kj ls ckgj fudyus okys gksrs gh gSa fd rqjUr Phone dh ?k.Vh ctus yxrh gSA Phone dh ?k.Vh dk ctuk ,d izdkj dk Event gSA Real Life esa dbZ ckjs ,sls Events gksrs gSa] ftUgsa ckdh lHkh dkeksa dks Suspend djds rqjUr Respond djuk iMrk gSA mnkgj.k ns[ksa rks ge pkgs ftruh Hkh tYnh esa gksa] ysfdu vxj Phone dh ?k.Vh ctrh gS] rks gesa ml Phone dks Attend djuk gh iMrk gSA blh Concept dks tc ge Programming ds lUnHkZ esa ns[krs gSa] rc fdlh Program o mlds User ds chp ftruh Hkh Activities gksrh gSa] mu lHkh Activities dks tkok esa Events dgk tkrk gSA User Keyboard ls dksbZ Key Press djrk gS ;k Mouse ls Application ds fdlh Command Button ij Click djrk gS ;k Application Program ds Window dks Resize djrk gS] Software ;k Hardware dk Fail gksuk] fdlh List esa ls fdlh Item dks Select djuk] Timer ds Counter dk Increment gksuk vkfn fofHkUu izdkj ds Events gSaA

tc User fdlh Program ds lkFk Interaction djrk gS] rc Computer ,d Event Object Create djrk gSA ;s Event Object ml Action dks Represent djrk gS] ftls User us Perform fd;k gSA ;kuh ekuyks fd User us fdlh Application ds fdlh Button ij Click fd;k] rks Computer ,d Object Create djsxk vkSj ml Object }kjk Click Event Represent gksxkA fQj ge bl Click Event dks ,d Event Handler Coding }kjk Handle dj ldrs gSa vkSj og dke djokrs gSa] tks Click Event ds Generate gksus ij djokuk gksrk gSA 84 Any Question or Suggestion, Just Discuss Here...

Java in Hindi ;s Event Handler Code gh ;s r; djrk gS fd fdlh Event dks fdl izdkj ls Handle djuk gSA fdlh Event dks fofHkUu izdkj ls Drive djds Program Develop djus o mls Handle djus dh rduhd dks Event Driven Programming dgrs gSa] ftlesa fofHkUu izdkj dh Events dks Response djus okys Code Handlers fy[k dj Programming ;k Development fd;k tkrk gSA tkok ,d Pure Object Oriented Programming Language gS] blfy, ge bl Language esa fdlh Hkh pht dks ,d Object ds :i esa Represent djrs gSaA blhfy, User }kjk fdlh Hardware dks Access djus ls dksbZ Event Generate gks ;k fdlh Software }kjk dksbZ Event Generate gks] nksuksa gh fLFkfr;ksa esa fdlh Event dks Represent djus ds fy, ,d Event Object Create gksrk gSA GUI Programming esa Event Handle djuk lcls t:jh dke gksrk gSA GUI Program ;k Event Driven Programming Modal esa gekjk GUI Program User ds fdlh Hkh Action dk

bUrtkj djrk jgrk gSA

tc User ml Application ds lkFk fdlh izdkj dk Interaction djrk gS] rks ml Interaction ls lEcaf/kr dksbZ uk dksbZ Event Generate gksrk gS vkSj ml Event dks Handle djus ds fy, dksbZ uk dksbZ Handler fy[kk x;k gksrk gS] tks fd Event ds Response esa Execute gks tkrk gSA GUI dh lcls cMh fo”ks’krk ;s gS fd fdlh GUI Application ds Operations ds Perform gksus ds Øe dks User fu/kkZfjr djrk gS] ;kuh og fdlh Application ij fn[kkbZ ns jgs fdlh Hkh Button dks ;k fdlh Hkh vU; Control dks fdlh Hkh le; Use dj ldrk gS] tcfd CUI Applications esa Program ds Execution dk Sequence Programmer r; djrk gS vkSj User dks mlh izdkj ls pyuk iMrk gS ftl rjg ls Programmer us Program dks fy[k dj r; fd;k gSA Event Driven Program fuEukuqlkj Execute gksrs gSa% Algorithm of GUI Application 1 START [Starting the Window Based GUI Application ] 2 CREATE GUI OBJECT [Create a GUI Application Object like A Window] 3 LISTEN EVENT [Listen for an Event Occurred by the Interaction] 4 IF EVENT = CLOSE APPLICATION [If Event is for closing the Application] EXIT ELSE PROCESS EVENT 5 GOTO STEP 3 [Go to the Step 4 again and get next Event ]


Java in Hindi Flow of GUI Application START

Create a GUI Interface Object

Listen for an Event

Is Event = Close Window

Yes

END

No Process the Event

Components of an Event

tkok esa fdlh Hkh Event dks rhu fgLlksa esa caVk gqvk ekuk tk ldrk gS% Event Object tc User Keyboard ds fdlh Button dks Press djds ;k Mouse ds fdlh Button dks Click djds fdlh Application ls Interact djrk gS] rc ,d Event Generate gksrk gSA Event Driven Architecture ij vk/kkfjr Operating System bl Event o Event ls Related t:jh Data dks Trap dj ysrk gSA mnkgj.k ds fy, User fdlh Application ds Window ij Click djrk gS] rc User us fdl Button ls Click fd;k gS vkSj fdl x, y Location ij Click fd;k gS] bl ckr dh tkudkjh Data ds :i esa mlh Application ds mlh Object dks okil Hkst nsrk gS] ftl Object ij Click djus ij Event Generate gqvk gksrk gSA tkok esa gj Event dks ,d Object }kjk Represent fd;k tkrk gS vkSj og Object Generate gksus okys Event ls lEcaf/kr fofHkUu tkudkfj;ksa dks Hold djds j[krk gSA Event Object ds fdlh Data Member ds eku esa ifjorZu gksus dk eryc gS fd dksbZ Event Generate gqvk gSA ;k fQj ge ,slk Hkh dg ldrs gSa fd fdlh Event Object ds fdlh Data Member ds eku esa ifjorZu gksus dks gh ge Indirectly Event Generate gksuk dg ldrs gSaA tkok esa fofHkUu


Java in Hindi izdkj ds Events dks Describe o Handle djus ds fy, dbZ Classes igys ls gh Develop djds Library ds :i esa iznku dj nh xbZ gSAa Event Source

Event Source ,d ,slk Object gS tks Event Generate djus esa l{ke gksrk gS ;k Event Generate djrk gSA Event rc Generate gksrk gS] tc fdlh rjhds ls fdlh Event Object dh Internal State ;kuh Object ds fdlh Data Member dh fLFkfr esa ifjorZu gksrk gSA dksbZ Event Source ,d ls vf/kd izdkj dh Events dks Hkh Generate dj

ldrk gSA

mnkgj.k ds fy, ;fn ge fdlh Button ij Click djrs gSa] rks ,d ActionEvent Object Generate gksrk gSA ActionEvent Class ds Object esa bl Event ds ckjs esa fofHkUu izdkj dh Information Stored jgrh gSaA Event Handler

Event – Handler ,d Method gksrk gS tks Generate gksus okyh Event dks le>rk gS vkSj mls Process djus esa l{ke gksrk gSA Event Handler Method ,d Event izdkj ds Object dks Parameter ds :i esa ysrk gSA

ActionEvent Class esa getSource() uke dk ,d Method gksrk gSA ;s Method ml Component dk Reference Return djrk gS] ftlus Event Generate fd;k gSA ;kuh fdlh Application Window ij fLFkr ,d Command Button dks Click djus ij tks Click Event Generate gksrk gS] ml Click Event dks Generate djus okys Command Button dks getSource() Method Refer djrk gSA import java.awt.*; import java.applet.*; public class DrawStringAppletWithEvent extends Applet { TextField textBox = new TextField(50); public void init() { add(textBox); } public void paint(Graphics firstString) { firstString.drawString("Enter String in Text Box ", 6, 50); String strOfTextBox = textBox.getText();

}

firstString.drawString("String in Text Box is ", 6, 100); firstString.drawString(strOfTextBox, 30, 120);


Java in Hindi

}

public boolean action(Event evnt, Object obj) { repaint(); return true; }

Output:

bl Program esa geus Applet Class dks Derive djds DrawStringAppletWithEvent uke dh ,d Class cukbZ gS vkSj blesa Applet Class ds lHkh Attributes o Functionality dks Inherit fd;k gSA fQj geus TextField Class dk ,d Object textBox Create fd;k gS vkSj mldh Size 50 Define dh gSA ;kuh ge Text Box esa ,d le; esa 50 v{kj ns[k ldrs gSaA Create gksus okyk ;s Object vHkh Memory esa gh Create gqvk gSA ge bls rc rd Applet ij ugha ns[k ldrs gSa] tc rd fd ge bls Applet ij Add uk djsaA Applet ij bl textBox Object dks Add djus ds fy, Applet Class ds init() Method dks Override djds Create fd, x, textBox Object dks Add() Method }kjk Applet ij Add fd;k x;k gSA blds ckn Applet Class ds paint() Method dks Override djds ,d Message “Enter String in Text Box” dks Applet ij Display fd;k gSA fQj String Class dk ,d Object strOfTextBox Create fd;k gS vkSj TextField Class ds ,d getText() Method dks Call djds textBox Object esa Type fd, x, Texts dks bl strOfTextBox Object esa Hold fd;k x;k gSA fQj drawString() Method dk iz;ksx djds textBox esa Type dh xbZ String dks T;ksa dk R;ksa Applet ij Display djok fn;k x;k gSA bl Program esa geus action uke ds Event Method dks Override fd;k gS vkSj bl Method esa repaint() Method dks Call fd;k gSA bl Applet Program dks Compile djds Run djus ij gesa Applet Window esa ,d Text Box fn[kkbZ nsrk gSA bl Text Box esa tks dqN Hkh Type djds ge Enter Key Press djrs gSa] gesa og lc dqN Applet ij fn[kkbZ nsus yxrk gSA bldk dkj.k ;s gS fd tc Hkh ge Text Box esa dqN fy[krs gSa vkSj Enter Key Press djrs gSa] rks ,d action Event Generate gksrk gSA bl action Event ds Generate gksrs gh] bl Event dks Handle djus ds fy, Applet esa action uke dk ,d Method fy[kk x;k gSA bl Method esa repaint() Method dks Call fd;k x;k gSA


Java in Hindi tSls gh ge Text Box esa dqN Type djds Enter Key Press djrs gSa] action Event Trigger gksrk gSA ;s Event Trigger gksrs gh] action() Method Execute gksrk gS vkSj Applet ds paint() Method dks fQj ls Call djrk gS] ysfdu bl ckj Text Box esa tks Texts fy[kk tkrk gS] og Text Applet ij fn[kkbZ nsus yxrk gSA


Java in Hindi

Java Fundamentals The Core Concepts


Java in Hindi Java Fundamentals – Core Concepts

lHkh Programming Languages esa ;fn dksbZ pht Common gksrh gS rks og ;gh gS fd lHkh Programming Languages esa Develop fd, tkus okys Programs esa Data dks Input fd;k tkrk gS vkSj mu ij Required Processing Perform djds Output Generate fd;k tkrk gSA pwafd fdlh Hkh Computer Program esa lcls Important pht Data gh gksrh gS] blfy, gj Computer Program esa blh ckr dk /;ku j[kk tkrk gS fd Data dks fofHkUu rjhdksa ls Store fd;k tk,] rkfd mu ij fofHkUu izdkj dh Processing dks Apply djds fofHkUu izdkj ds Results Generate fd, tk ldsaA Data Memory esa fdl izdkj ls Store gksaxs vkSj fdl izdkj ls mu ij Processing dks Apply fd;k tk,xk] bl ckr dk Track j[kus ds fy, Programs esa Constants o Variables dk iz;ksx fd;k tkrk gSA

Constants

fdlh Hkh Computer Program esa ge fofHkUu izdkj ds ekuksa dks Computer esa Store djrs gSa] mUgsa Manage djrs gSa] mu ij Required Processing Apply djrs gSa vkSj muds ifj.kke dks Output esa izkIr djrs gSaA ;fn ge Real World esa ns[ksa rks nks rjg ds eku gksrs gSaA ,d eku os gksrs gSa ftUgsa dHkh Change ugha fd;k tkrk gSA tSls fd lky esa dqy 12 eghus gksrs gSaA eghuksa dh la[;k fuf”pr gSA dHkh Hkh fdlh Hkh lky esa 11 ;k 13 eghus ugha gks ldrsA blh rjg ls gj eghus dk ,d fuf”pr uke gksrk gSA gj Week esa lkr fnu gksrs gSaA gj fnu dk ,d fuf”pr uke gksrk gSA blh rjg ls PI dk eku 22/7 gksrk gSA ge le> ldrs gSa fd ,slh gh gtkjksa phtsa gSa] ftuds eku gesa”kk fuf”pr gksrs gSaA tks eku gesa”kk fuf”pr gksrs gSa] mu ekuksa dks Constants dgk tkrk gSA blh rjg ls fdlh Computer Program esa Use fd;k x;k og eku tks iwjs Program esa Change ugha gksrk gS] Constant dgykrk gSA ge fdlh Hkh Data dks eku ;k ekuksa ds ,d lewg ds :i esa eku ldrs gSaA ;kuh fdlh Hkh rF; dks Computer Program esa Represent djus ds fy, gesa ml rF; dks fdlh uk fdlh eku ds :i esa ifjHkkf’kr djuk gksrk gSA Computer esa ekuksa dks ;k rks Texts ds :i esa Represent fd;k tkrk gS ;k fQj fdlh vad ds :i esaA mnkgj.k ds fy, ;fn gesa lky ds dqy fnuksa dks Computer esa Store djuk gks rks ge vad 12 dks mi;ksx esa ysrs gSa] tks fd ,d la[;k gSA tcfd ;fn gesa fdlh eghus ds uke ekuk “January” dks Computer esa Store djuk gks rks ge Characters ds lewg dk iz;kssx djrs gSaA bl mnkgj.k ds vk/kkj ij ge dg ldrs gSa fd fdlh Hkh Real World eku dks Computer esa ;k rks fdlh vad ;k vadksa ds lewg ds :i esa Define fd;k tkrk gS ;k fdlh Character ;k Character ds lewg ds :i esaA fofHkUu vad ;k vadksa ds lewg dks ge Numeral Constants dg ldrs gSa vkSj fofHkUu Characters o Characters ds lewg dks Character ;k String Constants dg ldrs gSaA


Java in Hindi mnkgj.k ds fy, eku yks fd gesa 100 :i;s dk 6.0 izfr”kr C;kt Kkr djuk gSA ;s Calculation ge fuEukuqlkj dj ldrs gSa% Interest = 100 * 6.0 / 100

bl Line esa Numerical eku 100 o 6.0 fLFkr eku gSa] blfy, bUgsa Constant dgk tkrk gSA ekuyks fd gesa fdlh Program esa bl Calculation dks dbZ ckj Perform djuk iMrk gSA bl fLFkfr esa ge bl Statement dks iwjs Program esa dbZ ckj fy[k ldrs gSaA ysfdu FkksMs le; ckn ;fn gesa 6.0 ds ctk; 7.0 izfr”kr C;kt Calculate djus ds fy, blh Program dks Modify djuk iMs] rks geus Program esa ftruh ckj bl Calculation dks Perform fd;k gS] mruh gh ckj vad 6.0 ds LFkku ij 7.0 dks Replace djuk iMsxkA ;fn gekjs Program esa 200 ckj bl Statement dks Use fd; x;k gks rks gesa gekjs Program esa 200 LFkkuksa ij 6.0 ds LFkku ij 7.0 djuk iMsxkA bl izdkj ls fdlh Program dks Modify djus esa dkQh le; yxrk gS vkSj xyfr;ka gksus dh Hkh dkQh lEHkkouk jgrh gSA bl izdkj dh fLFkfr;ksa dks Avoid djus ds fy, Programmers gesa”kk dqN Symbolic Constants dk iz;ksx djrs gSa] tks lkekU;r;k os “kCn gksrs gSa] tks Program esa fdlh eku dks Represent djrs gSaA gekjs bl Statement ds lEca/k esa ns[ksa rks 6.0 dks Represent djus ds fy, ge Percent uke dk ,d Symbolic Content Use dj ldrs gSa] tks Current Percent dks Represent djrk gS vkSj Program dh “kq:vkr esa Percent dks og nj iznku dj nsrs gSa] ftls iwjs Program esa Calculate djuk gSA tkok esa fdlh Constant dks Represent djus ds fy, tks Statement fy[kk tkrk gS] mls Constant Declare djuk dgrs gSa vkSj bls fuEukuqlkj Declare djrs gSa% final float PERCENT = 6.0;

tkok esa final “kCn dk iz;ksx rc fd;k tkrk gS] tc gesa tkok Compiler dks ;s crkuk gksrk gS] fd ge fdlh eku dks iwjs Program esa fLFkj ;k Constant j[kuk pkgrs gSaA float “kCn tkok Compiler dks ;s crkrk gS fd ge ftl Constant eku dks Store djuk pkgrs gSa] og eku ,d Floating Point eku ;k nleyo okyk eku gSA PERCENT “kCn ,d Symbolic Content gSA bl Statement esa = dk fpUg crkrk gS fd = ds Left Side esa tks Word gS og Word ml eku ds cjkcj gS tks = fpUg ds Right Side esa gS tks fd gekjs bl Statement esa 6.0 gSA

;kuh ge fdlh Calculation esa 6.0 fy[ksa ;k PERCENT fy[ksa] nksuksa ls fudyus okyk ifj.kke leku gh izkIr gksxk] D;ksafd nksuksa gh leku eku dks Represent dj jgs gSaA ;kuh ;fn ge pkgsa rks fuEukuqlkj Hkh Interest Kkr djus dk Statement fy[k ldrs gSa% Interest = 100 * PERCENT / 100;

lkekU;r;k Symbolic Constants dks Program ds vU; Codes ls vyx fn[kkus ds fy, Symbolic Constants dks UPPERCASE esa fy[kk tkrk gSA


Java in Hindi Variables

Program ds os eku tks iwjs Program esa le;≤ ij vko”;drkuqlkj cnyrs jgrs gSa] Variables dgykrs gSaA Variables dHkh Hkh fdlh fLFkj eku dks Represent djus ds fy, Use ugha fd, tkrs gSaA tc Hkh gesa fdlh Constant dks Program esa Use djuk gksrk gS] rks ml Constant dks Represent djus ds fy, gesa Symbolic Constants dh t:jr gksrh gSA

bu Symbolic Constants dks gh Literal Hkh dgk tkrk gSA loky ;s iSnk gksrk gS fd Program esa Variables dh D;k t:jr gS\ bls le>us ds fy, fiNys Statement dks gh ysrs gSa] tks fd fuEukuqlkj gS% Interest = 100 * PERCENT / 100;

bl Statement esa Interest ,d Variable gSA ;kuh fdlh Calculation ds Result dks Store djus ds fy, gesa gekjs Program esa gesa”kk ,d ,slh Memory dh t:jr gksrh gS] ftlesa fofHkUu izdkj ds cnyrs gq, eku Store gks ldsaA bl Statement }kjk ge dsoy 100 dk gh PERCENT Kkr dj ldrs gSaA ysfdu lkekU;r;k gesa vyx&vyx LFkkuksa ij vyx&vyx izdkj ds ekuksa dk Percent Kkr djuk gksrk gSA ,sls esa gj la[;k dk Percent Kkr djus ds fy, ;fn gesa vyx ls Program cukuk iMs rks ;s ,d cgqr gh vlqfo/kktud ckr gksxhA Program ,slk gksuk pkfg, fd fdlh ,d gh Program ls ,d izdkj ls Perform gksus okyh fofHkUu izdkj dh Calculations dks Perform fd;k tk ldsA ;kuh ge ;fn 100 dh txg 200 dj nsa] rks gesa 200 dk Interest izkIr gks tk,A ;fn ge Program dks Multipurpose cukuk pkgrs gSa] rks gesa 100 dks Hkh fdlh Symbolic rjhds ls Represent djuk gksxkA ;s dke ge fuEukuqlkj Statement }kjk dj ldrs gSa% Principal = 100; Interest = Principal * PERCENT / 100;

ge ns[k ldrs gSa fd ;fn Principal dk eku 100 ls 200 dj fn;k tk, rks Interest uke ds Variable esa gesa Principal 200 dk Interest izkIr gksxkA pwafd ewy/ku 100 ds Symbolic Representative Principal dk eku cny dj 200, 300, 400 vkfn fd;k tk ldrk gS] blfy, Principal Hkh ,d Variable gS vkSj Principal ds Change gksus ls Calculate gksus okys Interest esa Hkh ifjorZu gksrk gS] blfy, Interest Hkh ,d Variable gSA

Naming Constants and Variables – The Identifiers

tks lcls igyh Computer Language Develop dh xbZ Fkh og xf.krKksa ds fy, xf.krh; leL;kvksa dks gy djus ds fy, Develop dh xbZ FkhA bl otg ls fofHkUu Calculations esa Use fd, tkus okys Variables o Calculations dks bl izdkj ls Model fd;k x;k Fkk ftl izdkj ls xf.krK le>rs FksA mnkgj.k ds fy, iqjkus le; esa C;kt Kkr djus ds fy, xf.krK fuEukuqlkj Syntax dk iz;ksx djrs Fks% 93 Any Question or Suggestion, Just Discuss Here...

Java in Hindi a = b * c / 100;

ge bl Statement }kjk ;s irk ugha yxk ldrs gSa] fd ;s Expression fdl dke dks iwjk djus ds fy, fy[kk x;k gSA bl izdkj dh Coding fy[kus ij Programmers dks cgqr lkjk Comment Hkh fy[kuk iMrk Fkk] rkfd ;s Clear gks lds fd Program D;k dke djsxkA ;kuh ge mijksDr Statement dks fcuk mfpr Comment ds ugha le> ldrs gSaA ;fn mijksDr Statement dks fuEukuqlkj fy[kk tk, rks ge cgqr gh vklkuh ls tku ldrs gSa fd ;s Statement D;k dke djus ds fy, fy[kk x;k gS% Interest = Principal * PERCENT / 100;

;fn ge bl rjg ls Variables ds uke pqurs gSa rks ge fcuk fdlh fo”ks’k Commenting ds Hkh vklkuh ls le> ldrs gSa fd Program D;k dke djus ds fy, cuk;k tk jgk gS vkSj Program dk dksbZ Statement D;k dke dj jgk gSA ;kuh Program Lo;a gh Self Commenting cu tkrk gS vkSj Program dk gj Statement Lo;a gh crkrk gS fd dkSulk Statement D;k dke dj jgk gSA bu ukeksa dks Identifiers Hkh dgrs gSa] D;ksafd bu ukeksa dks Use djds gh ge fdlh Program Object dks Identify djrs gSaA cnyrs gq, (Variable) o fLFkj (Constant) ekuksa dks Represent djus ds fy, mfpr ukeksa dks pquus ds lEca/k esa tkok esa dqN fu;e Hkh gSaA ;kuh ge vadksa ;k v{kjksa ds fdlh lewg dks Identifier ds :i esa Use ugha dj ldrs gSaA tkok esa fdlh Identifier dk uke nsus dk igyk fu;e ;s gS fd fdlh Hkh Identifier (Variable ;k Constant) dk uke fdlh Character, $ ;k _ (Underscore) ds fpUg ls gh “kq: gks ldrk gSA Characters Uppercase ;k Lowercase fdlh Hkh rjg ds gks ldrs gSa vkSj ge bu Valid Characters dh vkil esa Mixing Hkh dj ldrs gSaA ;fn gesa fdlh uke esa vad dk iz;ksx djuk gks] rks vadksa dk iz;kssx ge dsoy uke ds ckn esa gh dj ldrs gSaA mnkgj.k ds fy, fdlh fuEu uke Valid gSa% number number2 amount_of_sale $amount salary daysOfWeek monthsOfYear

blh rjg ls vkxs fn, tk jgs uke xyr gSa] D;ksafd ;s uke tkok ds Naming Rules dk iwjh rjg ls ikyu ugha djrs gSa% number# number2* 1amount_of_sale &$amount days Of Week months OfYear10


Java in Hindi “Java” Characterset izR;sd Hkk’kk esa fpUgks] vadksa] v{kjksa dk ,d lewg gksrk gSA bu fpUgks] vadksa o v{kjksa dks ,d fo”ks’k Øe esa j[kus ij ,d “kCn curk gS] ftldk fd viuk ,d [kkl vFkZ gksrk gSA tSls j~ $ v $ e~ feydj jke “kCn cukrs gSa ftldk viuk ,d mfpr vFkZ gSA blh rjg ^^tkok** esa Hkh dqN [kkl fpUgks] vadks o v{kjksa dks ekU;rk nh xbZ gS] ftuds feyus ls dqN [kkl vFkZ fudyrs gSaA bu vFkksZa dks okLrfod rkSj ij flQZ dEI;wVj gh le>rk gSA ;s “kCn lewg fuEu fyf[kr gSa] ftudk iz;ksx tkok dk Program fy[kus esa fd;k tkrk gS& 1 2 3 4

Uppercase (A-Z) and Lowercase (a-z) Alphabet 0 to 9 Digits Whitespace Characters (Blank Space, H-Tab, V-Tab, Form Feed, New Line Character, Carriage Return ) Special Characters , Comma ; Semi Colon : Colon ? Question Mark . Dot ' Single Quote " Double Quote | V-Bar $ Dollar Sign # Pound Sign & Ampersand * Asterisk ( Left Parentheses ) Right parentheses [ Left Bracket ] Right Bracket { Left Curly Brace } Right Curly Brace < Less Then Sign > Greater Then Sign Blank = Equal to \ Back Slash / Slash _ Under Score % Percent ~ Tilde ^ Upper Carat + Plus Minus ! Exclamation mark

“Java” Tokens ftl izdkj ls “kCn] fdlh Hkh iSjkxzkQ dh og y?kqRre bdkbZ gksrh gS] ftlesa ,d fo”ks’k vFkZ fo/keku jgrk gS] Bhd blh rjg bl Hkk’kk esa Hkh ,sls gh dqN “kCn] fpUg vkfn gSa] tks Lora= :i ls viuk dqN vFkZ j[krs gSaA ^^tkok** Hkk’kk dh og y?kqRre bdkbZ tks Lora= :i ls viuk dksbZ vFkZ j[krh gS] Vksdu~ dgykrh gSA tc ge fdlh Java Source Program dks Compile djrs gSa] rc Compiler ml Source Program esa Tokens dks Extract djrk gSA Token og Smallest Element gksrk gS ftldk Compiler ds fy, ,d Meaningful vFkZ gksrk gSA ;s Tokens gh Java Program ds Structure dks ifjHkkf’kr djrs gSaA ;kuh ;s r; djrs gSa] fd Java Program ds fofHkUu Statements Java ds fu;eksa ds vuqlkj fy[ks x, gSa vFkok ughaA lHkh Languages esa ;s Tokens gksrs gSa vkSj budh la[;k lHkh Hkk’kkvksa esa lkekU;r;k ikap gh


Java in Hindi gksrh gSA ;s ikap Tokens Keywords, Literals, Identifiers, Operators o Separators gksrs gSaA Java Compiler bu Tokens ds vykok Blank Space o Comments dks Hkh igpkurk gSA tc Java Program dks Compile fd;k tkrk gS] rc Java Compiler Java Program esa ls lHkh Comments o Blank Spaces dks Remove djds “ks’k Program esa ls Tokens dks izkIr dj ysrk gSA tks Tokens mls izkIr gksrs gSa] og Compiler mu Tokens dks Computer ds le>us ;ksX; Machine Independent Java Bytecodes esa Convert dj nsrk gSA Keywords ;k Reserve Words ^^tkok** Hkk’kk ds dqN Reserve Words gSaA budk iz;ksx lkekU; :i esa ugha gksrk gS] cfYd ;s dqN [kkl dkeksa esa mi;ksx esa vkrs gSa vkSj budk Compiler ds fy, fo”ks’k vFkZ gksrk gS] ftUgsa le> dj Compiler ml fo”ks’k vFkZ ds vuqlkj dke djrk gSA abstract catch do finally import new short this volatile

assert char double float instanceof package static throw while

Boolean class else for int private strictfp throws

break const enum goto interface protected super transit

byte continue extends if long public switch try

case default final implements native return synchronized void

;s Keywords Java ds fy, Reserve fd, x, gSaA ysfdu bu esa ls dqN Keywords ,sls gSa] ftUgsa Future Use ds fy, Reserve fd;k x;k Fkk ysfdu vHkh rd mi;ksx esa ugha fy;k x;k gSA lEHkor;k Future esa dHkh fdlh t:jr dks iwjk djus ds fy, budk mi;ksx fd;k tk,A blds vykok tkok esa true, false o null dks Hkh Reserve fd;k x;k gSA gkykafd ;s Keywords ugha gSa] ysfdu bu ukeksa dk iz;ksx fdlh Variable, Constant ;k Class ds uke ds :i esa ugha fd;k tk ldrk gSA

Identifiers Identifiers os Token gksrs gSa] tks uke dks Represent djrs gSaA ;s os uke gksrs gSa tks ,d Programmer vius Program ds fofHkUu vo;oksa dh Compiler ls igpku djokus ds fy, mUgsa iznku djrk gSA ;s uke Variables, Methods o Classes dks iznku fd, tkrs gSaA geus Java dk tks igyk Program Create fd;k gS] mldh Class dk uke geus HelloWorld fn;k gS vkSj ml File dk uke HelloWorld.Java fn;k gSA ;s nksuksa os uke gSa] ftUgsa Compiler igpkurk gSA ;s uke Compiler ds fy, Identifiers gSaA lHkh izdkj dh Hkk’kkvksa esa pkgs og Real World Language gks ;k dksbZ Computer Language, uke nsus ;k uke j[kus dk ,d fuf”pr fu;e gksrk gSA mnkgj.k ds fy, Real World esa Hkh ge fdlh dk dksbZ ,slk uke ugha j[krs gSa] ftlds mPpkj.k ls xyr vFkZ fudyrk gksA


Java in Hindi blh rjg ls Java Language esa Hkh uke nsus ds dqN fu;e gSa vkSj ge bu fu;eksa dh vogsyuk ugha dj ldrs gSaA tkok esa fdlh Identifier (Variable ;k Constant) dks uke nsus ds fu;eksa dks ge fuEukuqlkj Point Wise fy[k ldrs gSa% 1 Java esa fdlh uke dh “kq:vkr Alphabet ds fdlh Hkh Character ls pkgs og Character Lowercase gks ;k Uppercase vkSj Under Score ;k Dollar ds fpUg ls gks ldrh gSA 2 fdlh Identifier ds uke esa 0 ls 9 rd ds vadksa dk Hkh iz;ksx fd;k tk ldrk gS] ysfdu ;s vad uke ds chp esa ;k vUr esa vk ldrs gSaA uke dh “kq:vkr fdlh vad ls ugha gks ldrhA 3 uke esa fdlh Special Symbols tSls fd Blank Space, % dk fpUg ;k fdlh Reserve Word dk iz;ksx ugha fd;k tk ldrk gSA Java esa dqN vU; fu;eksa dk Hkh ikyu fd; tkrk gSA gkykafd ;fn bu fu;eksa dk ikyu uk fd;k tk,] rks Hkh Program iwjh rjg ls dke djrk gS] ysfdu fQj Hkh budk ikyu djuk Bhd jgrk gSA budk ikyu djus ls Program vf/kd ljy o le>us ;ksX; gks tkrk gSA

;fn uke esa nks ls vf/kd “kCnksa dk iz;ksx djuk gks] rks uke dh “kq:vkr Lowercase Letter ls djuh pkfg,A ckdh ds vU; ftrus Hkh Words gSa] muds ukeksa dh “kq:vkr Capital Letter ls djuh pkfg,A tSls totalSellingAmount ,d lgh uke gSA bl uke dks iuk dkQh ljy jgrk gS] tcfd totalsellingamount ;k TOTALSELLINGAMOUNT ,d xyr uke gSA

Literal tSlkfd geus igys Hkh dgk fd dqN phtksa ds eku Real World esa Hkh fLFkj gksrs gSaA tSls lIrkg ds lkr fnuksa ds gj fnu dk ,d fuf”pr uke] lky ds ckjg eghuksa ds gj ekg dk ,d fLFkj ukeA PI dk eku tks fd 3.14 ds yxHkx gksrk gSA ,sls gh gtkjksa mnkgj.k fn, tk ldrs gSaA ftl rjg ls Real World esa dqN eku fLFkj gks ldrs gSa mlh rjg ls fdlh Hkh Computer Hkk’kk esa Hkh dqN ,sls ekuksa dh t:jr iM ldrh gS] ftudk eku iwjs Program esa fLFkj jgsA bl izdkj ds Data dks Computer Language esa Literals dgk tkrk gSA ;s eku Numerical gks ldrs gSa vkSj Non-Numerical Hkh gks ldrs gSa vkSj ekuksa dk ,d lewg Hkh gks ldrk gSA Literals dks Constants Hkh dgrs gSa vkSj bUgsa lkekU;r;k Symbolic Form esa Represent fd;k tkrk gS vkSj bUgsa budh izd`fr ds vk/kkj ij fuEukuqlkj Hkkxksa esa foHkkftr djds le>k tk ldrk gSA

Integer Constant iw.kkZd a la[;k,a Integer dgykrh gSaA ftu la[;kvksa ds eku esa nleyo ugha gksrk gS] os la[;k,a iw.kkZad la[;k,a dgykrh gSaA blesa $ o – fpUg gks ldrs gSaA ftl vad ij dksbZ fpUg u gks og +ve gksrh gSaA tSls 124, 3223, 545, 23 vkfnA bles la[;kvksa ds chp dksek dk iz;ksx ugh fd;k tkrk gSA tSls 1233,33,000 ,d xyr fLFkjkad gSA ;s eq[;r% rhu rjg ds gksrs gS& Decimal Octal Constant

& blesa 0 ls 9 rd dh la[;k, gksrh gSaA & blesa 0 ls 7 rd dh la[;k,a gksrh gSa] o gj la[;k dh “kq:vkr O ls gksrh gSA 97 Any Question or Suggestion, Just Discuss Here...

Java in Hindi Hexadecimal

& blesa 0 ls 9 rd ds vad o A ls F ;k a ls f rd ds v{kj lfEefyr gksrs gSaA bu la[;kvksa dh “kq:vkr geas”kk ox ;k OX ls gksrh gSA

Floating Point Constant ;s os eku gksrs gSa ftuesa n”keyo gksrk gSA ;g okLrfod fLFkjkad (Real Constant) dgykrk gSA bls nkss Hkkxksa esa ckaVk tk ldrk gS& ⇒ Fractional Form:- bl izdkj ds fLFkjkad esa de ls de ,d vad n”keyo ds iwoZ o ,d vad n”keyo ds ckn gksuk pkfg;sA ckdh ds lkjs fu;e Integer Constant dh rjg gh gSaA tSls %& 12122-122] 11-22 vkfn ⇒ Exponent Form :-blds nks Hkkx gksrs gSa& (1) Mantissa o (2) Exponent blesa cMh & cMh la[;kvksa dks ?kkrkad ds :i esa n”kkZ;k tkrk gSA tSls 1200000000 dks ?kkrkad :i esa ge fuEukuqlkj Hkh fy[k ldrs gSaA 1200000000=1.200000000 X 1010 vc 1.2 Mantissa okyk Hkkx gksxk o 1010 Exponent okyk Hkkx gks tk,xkA bl rjg ge fdlh Hkh eku dks ?kkrkad esa Convert djus ds fy;s fuEu lw= dk iz;ksx dj ldrs gSa & Value 1200000000

= =

Mantissa 1.2

e/E +E

Exponent 10

=

1.2+E10

bl rjg ls fdlh Hkh la[;k dk ?kkrkad :i izkIr fd;k tk ldrk gSA ;fn ?kkrkad /kukRed gks rks +e ;k +E vkrk gS vU;Fkk -e ;k -E vkrk gSA

Boolean Constants bu Constants dk iz;ksx true ;k false dks Represent djus ds fy, gksrk gSA Programming esa dbZ LFkkuksa ij ,sls ekuksa dh t:jr iMrh gS] tks fdlh Statement ds lR; ;k vlR; gksus dks Represent djrs gSaA

Character Constant tc fLFkjkad ds :i esa Alphanumeric Characters dk iz;ksx fd;k tkrk gS] rks bls Character Constant dgrs gSaA ;s rhu rjg ds gksrs gSa&  Single Character Constant bls ges”kk Single Quote esa can djrs gSA tSls ‘n’, ‘e’, ‘e’, ‘l’, ‘u’ vkfnA  String Constant bls ges”kk Double Quote esa can djrs gSaA tSls “Madhav“, “Raghav”, “Gopal” vkfn


Java in Hindi  Back slash Character Constant ^^tkok** Hkk’kk esa dqN Characters Back Slash ds lkFk iz;ksx dj ldrs gSa] ftudk mi;ksx eupkgk Output izkIr djus esa gksrk gSA ;s Control Characters gksrs gSa tks fuEukuqlkj gSa& ‘\\’ ‘\b’ ‘\f’ ‘\r’ ‘\’’ ‘\\’

‘\’ ‘\udddd ‘\n’ ‘\t’ ‘\”’ ‘\ddd’

Back Slash Backspace Form Feed Carriage Return Single Quote Back Slash

Continuation Unicode Character New Line Horizontal Tab Double Quote Octal Character

igys Computer tc T;knk fodflr ugha Fks rc dsoy English Language esa gh Information dks Store fd;k tkrk FkkA blds fy, dsoy ASCII Character Code dk iz;ksx fd;k tkrk FkkA ;s 8-Bit ij vk/kkfjr Fks blfy, dsoy 128 Characters dks gh Represent dj ldrs FksA mlds ckn tc dbZ Languages esa Data dks Store o Manage djus dh t:jr iMh] rc Unicode dk fodkl fd;k x;kA blesa 16-Bit Code ls Characters dk Representation gksrk gS] blfy, nqfu;k dh yxHkx lHkh Hkk’kkvksa ds fy, blesa Code miyC/k gksrs gSaA mnkgj.k ds fy, Unicode ‘\u0048’ Character ‘H’ dk Hexadecimal Representation gS tks fd Octal esa ‘\110’ ds leku gSA

Variables chtxf.kr esa fdlh leL;k dk lek/kku izkIr djus ds fy, geus Equations esa dbZ ckj x o y dk iz;ksx fd;k gSA fdlh Equation esa ;s x o y fdlh eku dks Represent djrs gSaA bUgsa pj (Variable) dgk tkrk gS] D;ksafd budk eku Equation esa le;≤ ij cnyrk jgrk gSA mnkgj.k ds fy, fuEu Equation nsf[k,& X = Y + 10

bl Equation esa X dk eku Y ds eku ds cnyus ds lkFk cnyrk jgrk gSA ;fn Y = 1 gks rks X = 11 gks tk,xkA ;fn Y = 20 gks rks X dk eku 30 gks tk,xkA ;kuh X ,d pj (Variable) gS ftldk eku fdlh vU; pj Y ds eku ij fuHkZj gSA ftl izdkj ls Y dk eku cnyrk gS mlh rjg ls X dk eku Hkh cnyrk jgrk gSA dbZ ckj dbZ Equations esa dqN ekuksa dks fLFkj dj fn;k tkrk gSA bu fLFkj ekuksa dks vpj eku (Constants) dgrs gSa] D;ksafd budk eku iwjs Equation esa dgha ij Hkh ugha cnyrk gSA tSls ekuyks fd% pi = 3.14 X = 2 * pi * R

bl Equation esa Hkh ge ns[k ldrs gSa fd bl pj (Variable) X dk eku R ij fuHkZj gSA ;fn R dk eku cnyk tk, rks X dk eku Hkh cny tkrk gS] tcfd R dk eku cnyus ij Hkh pi ds eku esa fdlh izdkj dk dksbZ ifjorZu ugha gksrk gSA blfy, ge dg ldrs gSa fd R o X pj (Variable) eku (Data) dks Represent dj jgs gSa tcfd pi ,d vpj (Constant) eku (Data) dks Represent dj jgk gSA


Java in Hindi Computer esa fdlh Hkh eku (Data) ds lkFk fdlh Hkh izdkj dh izfØ;k rHkh dh tk ldrh gS] tc og Data Memory esa Stored gksA Computer esa ekuksa dks Store djus ds fy, Computer Memory Location dk iz;ksx djrk gSA

pwafd Java esa ge Directly fdlh Hkh Memory Location dks Access ugha dj ldrs gSa] blfy, gesa fdlh Memory Location dks dksbZ uke nsuk gksrk gSA bl uke }kjk gh Compiler fdlh Specific Memory Location dks Identify dj ikrk gSA ;s uke ,d Identifier gksrk gS tks Programmer Lo;a viuh bPNkuqlkj r; djrk gSA lkFk gh ge fdl izdkj ds eku dks Computer dh Memory esa Store djuk pkgrs gSa] ml eku ds izdkj ;kuh Data Type dks Hkh Compiler dks crkuk iMrk gSA Compiler ml Data Type ds vuqlkj Memory esa dqN Space Reserve dj ysrk gS vkSj ml Space dks Identify djus ds fy, ml Reserve fd, x, Memory Block dk ,d uke j[k nsrk gSA ;s uke ogh uke gksrk gS] tks Programmer r; djrk gSA

Operators fdlh Hkh izksxzkfeax Hkk’kk esa Mathematical o Logical Calculations djus ds fy;s dEI;wVj dks funsZf”kr djus okys fpUgksa dks Operators dgrs gSaA ;s ftu Elements ds lkFk fØ;k djrs gSa] mUgs bu Operators dk Operand dgrs gSaA Operators nks rjg ds gksrs gSa& Unary Operator ftl Operator dks dke djus ds fy;s flQZ ,d Operand dh vko”;drk gks mls Unary Operator dgrs gSaA tSls - ,d Unary Operator gSA ftl fdlh Hkh la[;k ds lkFk - fpUg yxk fn;k tkrk gS] ml la[;k dk eku cny tkrk gSA tSls 6 ds lkFk - fpUg yxk nsus ls la[;k -6 gks tkrh gSA Unary Operators fuEu gksrs gSaA & * + ~ + !

Address Operator Indirection Operator Unary Plus Unary Minus Bit wise Operator Unary Increment Operator Decrement Operator Logical Operator

Binary Operators ftu Operators dks dke djus ds fy;s nks Operands dh t:jr gksrh gS] mUgsa Binary Operators dgrs gSaA tSls 2 $ 3 dks tksMus ds fy;s nks Operands dh t:jr gksrh gS] vr% Plus ,d Binary Operator Hkh gSA ^^lh** ds Binary Operators dks Category ds vuqlkj fuEu Hkkxksa esa ckaVk x;k gS& A Arithmetic Operators


Java in Hindi budk mi;ksx xf.kr ds la[;kRed ekuksa dh x.kuk djus ds fy;s gksrk gSA ;s dqy ikap gksrs gSa& $ & * / %

nks Operands dks tksMus esa mi;ksx gksrk gSA igys Operand esa ls nwljs dks ?kVkus ds fy;s mi;ksx gksrk gSA nks Operands dks vkil esa xq.kk djus ds fy;s mi;ksx gksrk gSA HkkxQy izkIr djus ds fy;s mi;ksx gksrk gSA Hkkx ds ckn cpus okys “ks’kQy dks izkIr djus ds fy;s mi;ksx gksrk gSA

tSls% 4+2=6

4–2=2

4*2=8

4/2=2

2%4=0

ftl rjg ls ge Integer o Float izdkj ds ekuksa dks bu Operators dk iz;ksx djds tksM ldrs gSa] mlh rjg ls ge Strings ( Characters ds ,d lewg ) dks Hkh vkil esa tksM ldrs gSaA tSls & “Bal” “5” “30”

+ + +

“Gopal” “20” “Madhav”

= = =

“BalGopal” “520” “30Madhav”

Java esa Modules Operator dk iz;ksx Floating Point Values ij Hkh mlh izdkj ls fd;k tk ldrk gS] ftl izdkj ls Integer izdkj ds ekuksa ij fd;k tkrk gSA ;kuh X = 49 Y = 50.20 A = X % 10 = 9 (Resultant Reminder Value of A) B = Y % 10 = 0.20 (Resultant Reminder Value of B)

Relational Operators tc izksxzke esa nks ekuksa dh vkil esa rqyuk djuh gksrh gS] rc Relational Operators dk iz;ksx fd;k tkrk gSA budk iz;ksx fdlh izksxzke esa djus ij ;fn dFku lR; gksrk gS] rks izksxzke true Return djrk gS vU;Fkk false Return djrk gSA Relational Operators fuEu gSa& Operator Equal to Not Equal to Less then Greater then Less then or Equal to Greater then or Equal to

Mathematical Symbol = <> < > < >

“Java” Symbol == != < > <= >=


Java in Hindi Logical Operators tc nks ;k nks ls vf/kd Conditions ds lkFk izfØ;k djds ifj.kke izkIr djuk gksrk gS] rc Logical Operators dk mi;ksx fd;k tkrk gSA ;s Java esa eq[;r% nks gksrs gSa& 1

2

AND (&&) - tc nksuksa Conditions lR; gksa rks izksxzke true Return djrk gS] vU;Fkk false Return gksrk gSA OR ( || ) - tc nks esa ls dksbZ Hkh ,d Condition lR; gks rks true Return djrk gS] vU;Fkk false Return gksrk gSA

true Return gksus dk eryc gS fd Condition lR; gSA Condition lR; gksus dh fLFkfr esa dqN [kkl Statements dk Execution gksuk gksrk gSA

Assignment Operators tc gesa izksxzke esa fdlh osfj;scy dks fdlh izdkj dh x.kuk ls izkIr gksus okyk eku iznku djuk gks] ;k dksbZ fLFkj eku iznku djuk gks] rks bls ge Assignment Operators }kjk iznku djrs gSaA Assignment Operator eq[;r% ,d gh gS ysfdu bls fofHkUu :iksa esa iz;ksx dj ldrs gSaSA tks fuEukuqlkj gS& Operator = += -= *= /= %=

Declaration Assignment Assigning Sum Assigning Difference Assigning Product Assigning Dividend Assigning Reminder

Example A = 10 A += 10 A -= 10 A *= 10 A /= 10 A %= 10

Explanation A = 10 A = A + 10 A = A – 10 A = A *10 A = A / 10 A = A % 10

Increment and Decrement Operators tc ges fdlh osfj;scy esa Øe ls ,d tksMuk ;k ?kVkuk gks] rks ge Increment ( ++ ) ;k Decrement ( - - ) Operators dk iz;ksx djrs gSaA osfj;scy ds lkFk budh fn”kk cny nsus ls buds LoHkko esa ifjorZu vk tkrk gSA budk iz;ksx Looping Statements esa fd;k tkrk gS] tgka Øe ls fdlh Calculation dks rc rd djrs jguk gksrk gS] tc rd fd Condition vlR; uk gks tk,A fuEu mnkgj.k ns[ksa if sum = 10 ++sum = 11 sum++ =11 --sum = 9 sum-- = 9

1 + 10 = 11 10 + 1 = 11 -1 + 10 = 9 10 – 1 = 9

Conditional Operators ;g if . . . else Conditional Statement dk laf{kIr :i gSA bldk Syntax ? : :i dk gksrk gSA ;kuh blesa nks Operand gksrs gSaA ;fn Condition True gksrh gS rks igyk Statement


Java in Hindi Execute gksrk gS ;k igys osfj;scy dk eku Output esa izkIr gksrk gSA ;fn igyh Condition lR; ugha gksrh gS rks nwljs osfj;scy dk eku Return gksrk gSA bls ,d mnkgj.k ls le>s rks &

ekuk a = 2, b = 3, x = 4 vc ;fn ge pkgrs gSa fd Data Input ds le; y = x gks] rks a dk eku z esa Store gks tk, vU;Fkk b dk eku z esa Store gks tk, rks ;s dke ge fuEukuqlkj Statements fy[kdj dj ldrs gSa& if ( x = = y ) z = a; else z = b;

bls Conditional Operator }kjk fy[kus ij fuEukuqlkj fy[k ldrs gSa%

;kuh ;fn “krZ lR; gksxh rks z = a gks tk,xk vU;Fkk z = b gks tk,xkA Bitwise Operators bu Operator dk mi;ksx fcV dks tkapus vkSj Bit dks nk;sa ls ck;sa ;k ck;sa ls nk;sa f[kldkus ds fy;s gksrk gSA bl Operator dk mi;ksx lh/ks gh dEI;wVj dh Bits ij dke djus ds fy;s gksrk gSA bl Operator dk iz;ksx gesa”kk Integer izdkj ds Data Type ds lkFk gh gksrk gSA bls vPNh rjg rHkh le>k tk ldrk gS tc izksxzfeax dk Bhd&Bhd Kku gks tk,A blfy;s bls vkxs le>k;k tk,xkA bldk iz;ksx rc fd;k tkrk gS tc fdlh osfj;scy esa LVksj eku dks cnyuk gksrk gSA ;s Operators fuEukuqlkj gSa& & | ^ ~

AND OR Exclusive OR Ones Compliment

Shift Operators Computer dh Memory esa lHkh Data Binary Format esa Store gksrs gSa] ftlesa gj Bit dk eku ;k rks 1 ;k fQj 0 gksrk gSA ekuyks fd ge 0 ls 4 rd dh la[;k dks Memory esa Store djsa] rks os la[;k,a fuEukuqlkj Store gksaxh& Decimal Number 0 1

Binary Equivalent

0000000000000000 0000000000000001


Java in Hindi 2 3 4

0000000000000010 0000000000000011 0000000000000100

Shift Operators os Operators gksrs gSa tks lh/ks gh Data ds Bits ij dke djrs gSa vkSj Data ds Bits dks Left ;k Right esa Shift djrs gSa ftlls Data ds eku esa ifjorZu gks tkrk gSA ge Shift Operators dk iz;ksx dsoy Integer izdkj ds ekuksa ij gh dj ldrs gSaA ;s Operators fuEukuqlkj gSa& << >> >>>

SHIFT LEFT SHIFT RIGHT UNSIGNED SHIFT

;fn ge ekuysa fd Memory esa eku 1 Stored gS vkSj ge bl ij Left Shift Operator dk iz;ksx djsa rks ge ;s dke fuEukuqlkj dj ldrs gSa& ( 1 << 4 )

=

( 0000000000000001 << 0000000000010000 ) =

16

ge ns[k ldrs gSa Left Shift Operator Bit 1 dks pkj Bit Left esa Shift dj jgk gS] ftlls eku 1 dk eku cny dj eku 16 gks tkrk gSA blh rjg ls 16 ij ge Right Shift Operator dk fuEukuqlkj iz;ksx dj ldrs gSa& ( 16 >> 3 ) = ( 0000000000010000 >> 0000000000000010 )

=

2

;fn gesa la[;k 16 dk fpUg cnyuk gks rks ge bl ij Negation dk iz;ksx djds blds lkjs Bits dks mYVk djrs gSaA ;kuh ~ (16) = ~( 0000000000010000 ) = (1111111111111101 ) =

-16

Punctuation dqN Special Symbols dk iz;ksx izksxzke esa “kCnksa o okD;ksa dks vyx djus ds fy;s fd;k tkrk gSA bUgs Punctuation ;k Separator Hkh dgrs gSaSA [] {} ( ) , ; : .

Array dh Size Define djus esa mi;ksx gksrk gSA lHkh Functions ds Executables Code bUgh dks’Bdks ds chp fy[ks tkrs gSaA ;s fpUg crkrk gS fd Use gks jgk Statement ,d Function gSA bls Separator dh rjg Use djrs gSaA gj Executable Statement dk vUr Semi Colon ls gh gksrk gSA Label Statement esa Use gksrk gSA Class ls Package o Sub-Packages dks Separate djus ds fy, bldk iz;ksx

fd;k tkrk gSA


Java in Hindi new Operator bl Operator dk iz;ksx fdlh Class dk u;k Instance ;k Object Create djds mls Memory iznku djus dk dke djrk gSA bls le>us ls igys gesa Class dks le>uk t:jh gksrk gS] rHkh bldk iz;ksx Bhd ls le> esa vkrk gSA

Precedence Of Operators ^^lh** Hkk’kk esa gj Operator dk ,d izkFkfedrk dk Øe gksrk gSA ftlls x.kukvksa esa gksus okyh ijs”kkfu;ka lekIr gks tkrh gSaA tSls fuEu Expression ns[ksa %& 11 + 23+20/6 – 4 = 5 11 + 23+20/6 – 4 = 27 11 + 23+20/6 – 4 = 33.333

bl rjg ls ftl ifj.kke dh gesa t:jr gS] og dkSulk gS] ;s irk yxkuk cgqr gh eqf”dy gks tk,xk D;ksafd rhuksa gh eku lgh gSaA ,sls esa ,d ,sls Øe dh vko”;drk gqbZ] ftlls ;g irk py lds fd igys dkSulh x.kuk gksxh o ckn esa dkSulh] rkfd gesa izkIr gksus okyk eku ogh gks tks ge pkgrs gSaA ^^tkok** esa bl izdkj dh ijs”kkuh ls cpus ds fy;s Operators dks ,d izkFkfedrk Øe esa O;ofLFkr fd;k x;kA blesa x.kuk, blh Øe esa gksrh gSaA tks Operator izkFkfedrk Øe esa igys vkrk gS] mlds Operands dh x.kuk igys gksrh gS vkSj tks Operator izkFkfedrk Øe esa ckn esa vkrk gS] mlds Operands dh x.kuk ckn esa gksrh gSA ;s izkFkfedrk Øe Lkkj.kh fuEukuqlkj gS& Category Highest Precedence Unary

Multiplication Additive Shift Relational

Equality Bit wise AND

Operator ( ) [ ] . + ~ ! ++ -* / % + << >> >>> < <= >= > == != &

Operations Function Call Array Subscript Dot Operator Unary Plus Unary Minus Bit wise 1st complement Logical Negation Increment Decrement Multiply Divide Reminder Binary Plus Binary Minus Shift Left Shift Right Unsigned Shift Less Than Less Than of equal to Greater Than or Equal to Greater Than Equal To Not Equal To Bit wise AND

Precedence 1 2

Associatively Left To Right Right To

3 4 5

Left Left To Right Left To Right Left To Right

6

Left To Right

7

Left To Right L to R

8


Java in Hindi Bit wise XOR Bit wise OR Logical AND Logical OR Conditional Assignment

^ | && || ?: = *= /= %= += -= &= ^= |= << >> ,

Comma

Bit wise XOR Bit wise OR Logical AND Logical OR Ternary Operator Simple Assignment Assign Product Assign Quotient Assign Reminder Assign Sum Assign Difference Assign Bit wise AND Assign Bit wise XOR Assign Bit wise OR Assign Left Shift Assign Right Shift Evaluate

9 10 11 12 13 14

L to R L to R L to R L to R L to R R TO L

15

L to R

Data Types

Real World esa Hkh Data (eku ;k ekuksa dk lewg [Value or a Set of Values]) dbZ izdkj ds gksrs gSaA tSls fdlh O;fDr dh mez dks ge la[;k ds :i esa fn[kkrs gSa tcfd ml O;fDr ds uke dks Characters ds lewg ds :i esa ifjHkkf’kr djrs gSaA

tkok esa fofHkUu izdkj ds Data dks Represent djus ds fy, eq[; :i ls nks rjg ds Data Type cuk, x, gS]a ftUgsa Øe”k% Primary (Standard) Data Type o Secondary (Abstract or Derived) Data Type dgk tkrk gSA Primitive Data Type Standard Data Type gksrs gSa] tcfd Derived ;k Abstract Data Type Primitive Data Type ij vk/kkfjr gksrs gSaA ^^tkok** ds fofHkUu Data Types dks ge

fuEukuqlkj foHkkftr dj ldrs gSa%

Data Type fdlh Hkh Programming Language dk ,d Fundamental Concept gksrk gSA Data Type dk iz;ksx djds ,d Programmer Compiler dks ;s crkrk gS fd mls fdl izdkj ds eku dks Store djuk gSA Compiler Programmer }kjk r; fd, x, Data Type ds vk/kkj

ij nks dke djrk gSA


Java in Hindi 1 Compiler Data Type ds vuqlkj Memory Reserve djrk gSA 2 ml Reserved Memory dks ,d uke nsrk gSA ftl rjg ls Real World esa NksVh pht dks j[kus ds fy, de txg dh t:jr gksrh gS vkSj cMh pht dks Store djus ds fy, vf/kd txg dh] mlh rjg ls Computer esa Hkh gksrk gSA ;fn Computer esa NksVs eku dks Store djuk gks] rks de Memory dh t:jr gksrh gS vkSj ;fn cMs eku dks Store djuk gks rks vf/kd Memory dh t:jr gksrh gSA bl rF; dks ,d mnkgj.k ls le>us dh dksf”k”k djrs gSaA ge tkurs gSa fd Computer esa ,d

Character Store djus ds fy, ,d Byte dh Memory dh t:jr gksrh gSA

;kuh ;fn fdlh Student dk uke 10 v{kjksa dk gks rks ml Student ds uke dks Memory esa Store djus ds fy, 10 Bytes dh t:jr gksxh tcfd ;fn fdlh Student dk uke 15 v{kjksa dk gks] rks 15 Bytes dh Memory dh t:jr gksxhA blh izdkj ls ;fn fdlh Student dh Age Computer esa Store djuh gks rks gesa de Memory dh t:jr gksxhA tcfd ;fn gesa fdlh ns”k dh dqy tula[;k dks Computer esa Store djuk gks rks gesa Age dks Store gksus ds fy, Age }kjk yh tkus okyh Memory dh rqyuk esa dkQh vf/kd Memory dh t:jr gksxh] D;ksafd Practically fdlh Hkh ns”k dh tula[;k de ls de gksxh rks Hkh djksMksa esa gksxhA ;kuh ;fn ge lkjka”k esa dgsa rks vyx&vyx izdkj (Data Type) ds ekuksa dks Memory esa Store djus ds fy, vyx&vyx Memory Size dh t:jr gksrh gSA

Identifier (Variable / Constant) Declaration tc gesa Computer esa fdlh eku ;k Data ij fdlh izdkj dh izfØ;k ;k Processing djuh gksrh gS] rc lcls igys gesa ml Data dks Computer dh Memory esa Store djuk iMrk gSA Computer dh Memory esa fdlh Data dks Store djus ds fy, Java esa fofHkUu izdkj ds Keywords r; fd, x, gSaA bu Keywords }kjk Compiler ;s r; djrk gS fd User dks fdl izdkj ds eku dks Store djus ds fy, Memory pkfg,A User ftl Data Type ds Keyword dk iz;ksx djrk gS] Compiler ml Keyword dh Size ds vuqlkj Memory Reserve dj ysrk gSA ysfdu vHkh Hkh ,d leL;k jgrh gS vkSj oks leL;k ;s gS fd Compiler tks Memory Reserve djrk gS] ml Memory ij ekuksa (Data) dks Hkstus ds fy, vkSj fdlh Processing esa mu Memory Locations ls Data dks okil izkIr djus ds fy, Programmer dks ,d uke dh t:jr gksrh gS] rkfd og Compiler dks ;s crk lds fd og fdl Memory Location ds eku dks Access djuk pkgrk gSA

blfy, Data Type dks Represent djus okys Keyword ds lkFk Programmer dks ,d uke Hkh nsuk gksrk gSA bl uke dks gh Variable ;k Constant dgrs gSaA Computer esa fdlh eku dks Store djus ds fy, Compiler dks nks ckrsa crkuh iMrh gSA igyh ;s fd Programmer fdl izdkj dk eku Memory esa Store djuk pkgrk gSA bl igyh ckr dks crkus ds fy, Programmer vko”;drkuqlkj fdlh Keyword dk iz;ksx djrk gSA


Java in Hindi bl Keyword ds vk/kkj ij Compiler Memory Reserve djrk gSA Compiler dks nwljh ckr ;s crkuh gksrh gS fd Programmer ml Reserve dh xbZ Memory dks fdl uke ls Access djsxkA blds fy, Programmer Data Type ds Keyword ds lkFk ,d uke Hkh r; djrk gS vkSj Compiler ml Reserve dh xbZ Memory dks og uke iznku dj nsrk gS tks Programmer r; djrk gSA ,d Programmer tc Compiler dks ;s tkudkjh nsrk gS fd og fdl izdkj ds eku dks Memory esa Store djuk pkgrk gS vkSj Compiler }kjk Reserve dh tkus okyh ml Memory dks fdl uke ls Access djuk pkgrk gS] rks bl iwjh izfØ;k dks Identifier Declaration dgrs gSaA dksbZ Identifier Declare djus ds fy, Programmer dks fuEu Syntax ds vuqlkj Java dh Source File esa viuk Code fy[krk gS& Identifier Declaration Syntax :

Data_Type Identifier_Name

;fn gesa ,d gh le; esa ,d gh Syntax }kjk ,d gh Data Type ds ,d ls vf/kd Identifiers Create djus gksa ;k Declare djus gksa rks gesa fuEu Syntax Use djuk iMrk gS& Identifier Declaration Syntax : Data_Type Identifier_Name_1, Identifier_Name_2, , . . . , Identifier_Name_n, Variable o Constants nksuksa gh izdkj ds Identifiers dks Declare djus dk rjhdk ,d tSlk gh gksrk gSA vUrj dsoy buesa Store fd, tkus okys Data dks Store djus ds rjhds dk gksrk gSA tc fdlh Identifier dks Declare djrs gh mls ,d fuf”pr eku iznku dj fn;k tkrk gS vkSj Programmer ml eku dks iwjs Program esa Change djuk ugha pkgrk gS] rks Declare fd, x, ml Identifier dks Constant dgk tkrk gSA tcfd ;fn Identifier dks Declare djus ds ckn Programmer mlesa ,d Permanent eku Initialize ugha djrk gS] rks ml Identifier dks Variable dgk tkrk gSA

Value Initialization tc Programmer fdlh Identifier dks Declare djrk gS vkSj Declaration ds lkFk gh mlesa dksbZ izkjfEHkd eku iznku dj nsrk gS] rks bl izfØ;k dks Identifier Initialization dgrs gSaA lkekU;r;k yxHkx lHkh Languages Identifiers dks Initialize fd;k tkrk gSA dqN High Level Languages ,slh Hkh gksrh gSa] ftuesa ;fn Identifier dks Declare djrs gh mls Initialize uk fd;k tk,] rks Hkh mu Languages dk Compiler mu Identifiers esa Default eku Initialize dj nsrk gSA Java Hkh ,d ,slh gh Language gSA ;fn ge blds fdlh Identifier dks Create djds mls dksbZ eku Initialize uk djsa] rks Hkh Java Lo;a mlds Identifiers dks muds Data Type ds vuqlkj Initialize dj nsrk gSA dbZ Hkk’kkvksa esa ;s lqfo/kk ugha gksrh gSA ftu Hkk’kkvksa esa ;s lqfo/kk ugha gksrh gS] mu Hkk’kkvksa esa ;fn fdlh Identifier dks Create djus ds ckn mls Initialize uk fd;k tk,] rks muesa Garbage Values Stored jgrh gSaA ;s Garbage Values dHkh&dHkh Program esa dkQh tfVy Errors Generate dj nsrh gSa] ftuls Program dks Debug djuk dkQh dfBu gks tkrk gSA


Java in Hindi tc ge fdlh Class ds fdlh Method esa Identifier Create djrs gSa] rc mu Identifiers esa ;s Default eku Initialize ugha gksrs gSaA bl fLFkfr esa gesa fdlh Class ds Methods esa ekuksa dks Initialize djuk t:jh gksrk gSA

Garbage Values Computer dh Memory ds gj Memory Location ij gj le; dksbZ uk dksbZ eku Store gksrk jgrk gSA fofHkUu Program ds fofHkUu izdkj ds Data Memory esa gj Location ij Store gksrs jgrs gSaA fdlh Program dks Terminate djus ds ckn Hkh mu LFkkuksa ij ,sls eku Store jgrs gSa] ftudk dksbZ eryc ugha gksrk gSA bu ekuksa dks Garbage Values dgk tkrk gSA Java ds fofHkUu Data Types dks ge eq[;r% nks Hkkxksa esa ckaV ldrs gSa % igys Hkkx dks Simple Data Type dg ldrs gSaA ;s Java ds eq[; Data Types gksrs gSaA bUgsa fdlh Hkh vU; Data Type ls Derive ugha fd;k x;k gksrk gSA bl Data Type dks eq[; :i ls pkj vU; Data Types Integer, Floating-Point, Boolean and Characters esa foHkkftr fd;k tk ldrk

gSA

nwljs Hkkx dks Composite Data Type dgrs gSa vkSj ;s iwjh rjg ls Simple Data Types ij vk/kkfjr gSaA ;kuh ;s Primary Data Type ds gh Modified :i gSaA Array, String, Class vkSj Interface (Methods) blds eq[; Hkkx gSaA Integer Data Types tc gesa fdlh leL;k ds ,sls Data dks Computer esa Store djuk gksrk gS] tks iwjh rjg ls iw.kkZad ysfdu fpUg okys (Signed) eku gksrs gSa] rc ge bl Class ds Data Type dk iz;ksx djds Identifiers Declare djrs gSaA bl Class ds Data Type dks Hkh ge pkj vU; SubClasses byte, short, int o long esa foHkkftr dj ldrs gSaA ;s pkjksa Data Types vyx&vyx Size dh Memory Reserve djrs gSaA budh Size fuEukuqlkj gksrh gS% Data Type Byte Short Int Long

Size 8 bits 16 bits 32 bits 64 bits

Integer Data Types of JAVA

Range -128 to +128 (-27 to +27-1) -32768 to +32767 (-215 to +215-1) (-231 to +231-1) (-263 to +263-1)

byte, short, int o long ;s pkjksa Java Keywords gSaA pwafd ;fn Computer esa Store fd;k tkus okyk eku cgqr gh NksVk gks] rks ge byte Data Type dk iz;ksx djrs gSaA tSls fd gesa Student dh Age dks Computer esa Store djuk gSA

pwafd ge lHkh tkurs gSa fd T;knkrj bUlkuksa dh mez dh vf/kdre lhek 100–125 lky rd gh gks ikrh gSA blfy, mez dks Computer esa Store djus ds fy, ge byte Data Type dk iz;ksx dj ldrs gSaA fdlh Student dh mez dks Computer esa Store djus ds fy, ge fuEukuqlkj Identifier Create dj ldrs gSa% byte age;


Java in Hindi ;fn gesa Computer esa fdlh Employee dh Salary Store djuh gks] rks ge Salary Store djus ds fy, fuEukuqlkj short izdkj dk Variable Create dj ldrs gSa% short salary;

pwafd ;fn fdlh Company esa Employees dh Salary ;fn 32767 rd gks] rks ge short Data Type dk iz;ksx dj ldrs gSaA ysfdu ;fn fdlh Company esa Employees dh Salary blls vf/kd gks rks ge Salary Store djus ds fy, fuEukuqlkj int izdkj dk Variable Declare dj ldrs gSa%

int salary;

dbZ ckj gesa dkQh cMh la[;kvksa dh x.kuk djus dh t:jr iMrh gSA mnkgj.k ds fy, ;fn gesa fdlh ns”k dh dqy tula[;k dks Computer esa Store djuk gks] rks gesa cgqr cMh la[;k dks Store djus dh t:jr iMrh gSA bl t:jr dks byte, short ;k int izdkj ds Data Type }kjk iwjk ugha fd;k tk ldrkA blfy, bl fLFkfr esa gesa long izdkj dk Variable Declare djuk gksrk gSA ;s Data Type rc Use fd;k tkrk gS tc cgqr cMs eku dks Computer esa Store djuk gksrk gSA bl Data Type dk Variable ge fuEukuqlkj Declare dj ldrs gSa% long population;

Floating – Point Data Types tc gesa Computer esa ,sls ekuksa dks Store djuk gksrk gS] ftuesa nleyo gks] rks ,slh la[;kvksa dks Computer esa Store djus ds fy, gesa Floating Point Data Type ds Variables Create djus iMrs gSaA bl izdkj ds Data dks Hkh nks Hkkxksa float o double esa foHkkftr fd;k tk ldrk gSA float izdkj dk Data Memory esa 32 Bits ;k 4 Bytes dh Space ysrk gS tcfd double izdkj dk Data Memory esa 64 Bits ;k 8 Bytes dh Space ysrk gSA tc gesa ,sls eku Computer esa Store djus gksrs gSa tks NksVs rks gksrs gSa ysfdu nleyo okys gksrs gSa rc ge float izdkj dk Variable Declare djrs gSa ysfdu tc cMs ekuksa dks Computer esa Store djuk gks] rc double izdkj ds Variables Declare djus iMrs gSaA float temperature; double speedOfLight;

tkok esa tc Initialize Hkh dk Hkh iz;ksx dk Declare

fdlh Floating Point Variable dks Create fd;k tkrk gS vkSj lkFk gh mls fd;k tkrk gS] rks Initialize fd, tkus okys eku ds lkFk gesa f ;k F Character djuk t:jh gksrk gSA D;ksafd tkok esa nleyo okys lHkh ekuksa dks double izdkj djuk gksrk gSA

ysfdu pwafd double izdkj dk Variable Memory esa 8 Bytes dh Space ysrk gS] blfy, ;fn gesa fdlh NksVs nleyo okys eku dks Computer esa Store djuk gks] rks ge float izdkj dk


Java in Hindi Variable Create dj ldrs gSaA ysfdu lkFk gh ;fn mls Initialize Hkh djuk gks rks ;s dke gesa fuEukuqlkj djuk gksrk gS% float temperature = 95.45F; float pi =3.1428f ;

;fn ge bl rjg ls eku ds lkFk f ;k F dk iz;ksx ugha djrs gSa] rks Compiler gesa fuEu Error nsrk gS] tks fd ;s crkrk gS fd Variable dks double izdkj dk Declare fd;k tkuk pkfg,] rkfd Variable esa Stored Data dk fdlh izdkj ls Loss uk gksA [Name of the main Class ].java:5: possible loss of precision found : double required: float float firstNumber = 5787.54; ^

Boolean Data Type Real World esa Hkh ge ns[krs gSa fd dbZ lokyksa ds tokc dsoy gka ;k uk esa fn, tkrs gSaA tSls fd dejsa dk cYc pkyw gS ;k ugha] Computer ij Internet pyrk gS ;k ugha] rqe cktkj x, Fks ;k ugha] vkfnA blh izdkj ls Computer esa Hkh gesa dbZ ckj bl izdkj ds ekuksa dks Store djuk iMrk gS tks dsoy gka ;k uk vFkok lR; ;k vlR; dks gh Represent djrs gSaA bl izdkj ds ekuksa dks Computer esa Store djus ds fy, ge Boolean Data Type dk Identifier Create djrs gSaA ;s Data Type Memory esa dsoy ,d Bit dh Space ysrk gSA ;fn Bit dk eku 1 gksrk gS rks mlesa true Store gksrk gS vkSj ;fn Bit dk eku 0 gks rks mlesa false Stored jgrk gSA Java esa 0 ;k 1 Store djus ds ctk; ge lh/ks gh true ;k false Store dj ldrs gSaA ,d Boolean Variable Declare djus ds fy, ge boolean Keyword dk iz;ksx djrs gSaA bl Data Type dk Variable Hkh mlh vU; lkekU; Variables dh rjg gh Declare fd;k tkrk

gSA tSls

boolean isGameOver;

Character Data Type dbZ ckj gesa Computer esa dsoy ,d gh Unicode Character Store djuk gksrk gSA dsoy ,d Character dks Computer esa Store djus ds fy, ge Java ds char Keyword dk iz;ksx djds Identifier Create djrs gSaA pwafd Unicode Characters 16 Bit ds gksrs gSa] blfy, char Data Type ,d 16 Bit Unsigned Value ds :i esa Character dks Store djrk gSA ge Character izdkj dk Variable fuEukuqlkj Create dj ldrs gSa& char firstInitial, middleInitial, lastInitial;

vHkh rd geus bl v/;k; esa tks dqN Hkh ikus dh dksf”k”k djrs gSaA fiNys v/;k; esa geus ,d String dks Output esa Print djus dk Program ns[kk gSA pfy,] blh rjg dk ,d vkSj mnkgj.k Program ns[krs gSaA


Java in Hindi Example

,d Program cukvks ftlesa vius ?kj dk Address Output esa Print gksuk pkfg,A Name of File = HomeAddress.java public class HomeAddress { public static void main(String args []) { System.out.println(“Bedal Road ”); System.out.println(“Behind of Vidhya Jyoti School ”); System.out.println(“Dist. Pali Falna Station “); } } Output Bedal Road Behind of Vidhya Jyoti School Dist. Pali Falna Station

bl Program esa ge ns[k ldrs gSa fd gesa tks Hkh Statement Output esa Print djuk gksrk gS] og Statement System.out.println() ds dks’Bd esa fy[krs gSaA pwafd ge ;gka ij Characters dk ,d lewg] ftls String dgrs gSa] Output esa Print djuk pkgrs gSaA blfy, geus ml String dks Double Quote ds vUnj fy[kk gSA println() Method out Object dk ,d Method gSA out Object Computer ds Console dks Represent djrk gSA ge tks dqN Hkh bl Object esa Hkst nsrs gSa] og lcdqN Screen ij Print gks tkrk gSA tSlkfd geus igys dgk fd println() out Object dk ,d Method gS] ftls out Object ds fy, Call fd;k tkrk gSA Java Programming esa ftl fdlh Statement ds ckn ( ) dk iz;ksx fd;k tkrk gS] og dksbZ uk dksbZ Method gksrk gS vkSj fdlh dke dks iwjk djrk gSA println() Method ds dks’Bd esa geus ,d String dks fy[kk gS tks fd Output esa Screen ij Print gks tkrk gSA ;s String println() Method dk Argument dgykrk gSA tc bl Program dks Compile fd;k tkrk gS] rc Java dk Compiler lcls igys ml uke dh Class dks [kkstrk gS] tks uke File dk uke gksrk gSA D;ksafd mlh Class esa main() Method gksrk gS vkSj Compiler gesa”kk main() Method dks gh lcls igys Compile djuk “kq: djrk gSA main() Method dks geus public Declare fd;k gSA ,slk blfy, fd;k gS rkfd ;s Method Command Prompt ls Access fd;k tk ldsA ;fn ;s Method public uk fd;k tk,] rks Program dks Run ugha fd;k tk ldrk gSA void Keyword dk iz;ksx blfy, fd;k gS] D;ksafd main() Method dHkh ,slk dksbZ eku Return ugha djrk gS] ftls dksbZ vU; Method Use dj ldsA static Keyword dk iz;ksx blfy, fd;k gS] rkfd main() Method ds eku esa fdlh izdkj dk dksbZ ifjorZu Command Prompt ls uk fd;k tk ldsA


Java in Hindi main() Method esa Argument ds :i esa String args[] fy[kk x;k gSA args ,d String dk Array gSA Array ds ckjs esa ge vkxs i
tc tkok ds fdlh Program dks Command Prompt ls Run fd;k tkrk gS] rc ml Program ds main() Method dks ;fn ge fdlh izdkj dk Argument nsuk pkgsa] rks Command Prompt ls ns ldrs gSaA Command Prompt ij fn, tkus okys Arguments args uke ds String izdkj ds Array esa Store gksrs gSa] ftUgsa main() Method esa Use djds dksbZ dke fd;k tk ldrk gSA main() Method dks [kkstus ds ckn Compiler main() Method ds Statement Block esa izos”k djrk gS] tgka mls System.out.println() Method izkIr gksrk gSA Compiler bl Method dks Compile djrk gS vkSj vkxs c
vkxs okil mls nwljk System.out.println() Method izkIr gksrk gSA Compiler bl Statement ds String dks Hkh Output esa Print djrk gSA fQj rhljs Statement dks Execute djrk gS vkSj rhljs Statement dks Output esa Print djrk gSA fQj mls main() Method dk Closing Curly Brace izkIr gksrk gS] tgka ls Compiler dk Program Control ckgj fudy tkrk gS vkSj Terminate gks tkrk gSA Example

,d ,slk Program cukvks ftlesa lHkh Arithmetical Operators dk iz;ksx fd;k x;k gksA Name of File = AllArithmetic.java public class AllArithmetic { public static void main(String args []) { int firstValue = 100; int secondValue; int addResult, subResult, mulResult, divResult, remResult; secondValue = 50; addResult = firstValue + secondValue; subResult = firstValue - secondValue; mulResult = firstValue * secondValue; divResult = firstValue / secondValue; System.out.println(firstValue + "+" +secondValue+ "="+addResult); System.out.println(firstValue + "-" +secondValue+ "="+subResult); System.out.println(firstValue + "*" +secondValue+ "="+mulResult); System.out.println(firstValue + "/" +secondValue+ "="+divResult); secondValue = 60; remResult = firstValue % secondValue; System.out.println(firstValue + "%" +secondValue+ "="+remResult);


Java in Hindi }

}

Output 100 + 50 = 150 100 - 50 = 50 100 * 50 = 5000 100 / 50 = 2 100 % 60 = 40

bl Program esa geus main() Method esa lcls igys ,d Integer izdkj dk fuEukuqkj Variable Create fd;k gS% int firstValue = 100;

;s Statement Memory esa Integer izdkj ds eku dks Store djus ds fy, pkj Bytes dh Space Reserve djrk gS] vkSj ml Space dk uke firstValue j[k nsrk gSA lkFk gh Variable ds fy, Memory Reserve djrs le; ;kuh Variable Create djrs le; gh ml Variable esa eku 100 iznku dj fn;k x;k gSA tc fdlh Variable dks Create djrs le; gh mls eku iznku dj fn;k tkrk gS rks bl izfØ;k dks Value Initialization dgk tkrk gSA fuEukuqlkj nwljs Statement esa geus ,d vkSj Variable Create fd;k gS] ysfdu bls Value Initialize ugha fd;k gSA int secondValue;

bu nksuksa Statements esa geus ,d le; esa dsoy ,d gh Variable Create fd;k gS tcfd rhljs Statement esa geus ,d lkFk Integer izdkj ds ikap Variables Create fd, gSaA tc gesa ,d gh Data Type ds dbZ Variables Create djus gksrs gSa] rc ge bl rjhds ls Variables dk Declaration dj ldrs gSaA Bhd mlh rjg ls ftl rjg ls geus bl Program esa fuEukuqlkj Statement }kjk ,d gh le; esa Integer izdkj ds ikap Variables Create fd, gSa& int addResult, subResult, mulResult, divResult, remResult; main() Method ds pkSFks Statement esa geus secondValue Variable dks fuEukuqlkj Statement }kjk eku iznku fd;k gS& secondValue = 50;

tc fdlh Variable dks Declare djrs le; eku iznku uk djds ckn esa eku iznku fd;k tkrk gS] rks eku iznku djus ds fy, Equal To Operator dk iz;ksx fd;k tkrk gSA bl Operator dks Assignment Operator Hkh dgrs gSa] blfy, bl izdkj ls eku iznku fd, tkus ds rjhds dks Variable Assignment ;k eku Assign djuk dgrs gSaA geus gekjs Program esa fuEukuqlkj pkj Statement }kjk ikap izdkj dh izfØ;k,a dh gSa tks firstValue o secondValue Variables ds ekuksa ds vk/kkj ij fofHkUu Arithmetical Operators ds iz;ksx }kjk Result Generate djrs gSa% addResult = firstValue + secondValue;


Java in Hindi subResult = firstValue - secondValue; mulResult = firstValue * secondValue; divResult = firstValue / secondValue;

nksuksa Variables ds ekuksa dk ;ksx gks dj addResult uke ds Variable esa ifj.kke Store gks tkrk gSA blh rjg ls firstValue Variable esa eku esa ls secondValue Variable dk eku ?kVkus ds ckn tks ifj.kke izkIr gksrk gS] og ifj.kke subResult uke ds Variable esa Store gks tkrk gSA rhljk Statement nksuksa Variables ds ekuksa dk xq.kk djrk gS vkSj ifj.kke dks mulResult uke ds Variable esa Store dj nsrk gSA pkSFks Statement esa firstValue Variable ds eku esa secondValue Variable ds eku dk Hkkx fn;k tkrk gS vkSj ifj.kke ds :i esa tks eku izkIr gksrk gS] mls divResult uke ds Variable esa Store dj fn;k tkrk gSA vc bu pkjksa ekuksa dks Output esa fuEukuqlkj Statutes }kjk Print dj fn;k tkrk gSA System.out.println(firstValue + "+" +secondValue+ "="+addResult); System.out.println(firstValue + "-" +secondValue+ "="+subResult); System.out.println(firstValue + "*" +secondValue+ "="+mulResult); System.out.println(firstValue + "/" +secondValue+ "="+divResult);

bu Statements esa println() Method dks vyx rjhds ls Use fd;k x;k gSA tc gesa ,d gh Line esa Numerical o Non-Numerical nksuksa rjg ds ekuksa dks Screen ij Print djuk gksrk gS] rc ge + Operator dk iz;ksx dj ldrs gSa] tSlkfd bu Statements esa fd;k x;k gSA pwafd Variables ds eku os uke gSa ftUgsa Compiler Directly igpkurk gS] blfy, bu ukeksa dks Double Quote esa cUn djus dh t:jr ugh gSA tcfd fofHkUu izdkj ds Operators ds fpUgksa dks ge String ds :i esa Output esa Print djuk pkgrs gSa] blfy, bUgsa Double Quote esa cUn fd;k x;k gSA String o Variables esa Stored eku dks ,d lkFk ,d gh println() Method ls Print fd;k tk lds] blds fy, t:jh gS fd buds chp + Operator dk iz;ksx mlh rjg ls fd;k tk,] ftl rjg ls mijksDr pkjksa Statements esa fd;k x;k gSA pwafd geus bl Program esa ftrus Hkh Variables Create fd, gSa] mu lHkh ds ekuksa dks Program esa dgha Hkh Change fd;k tk ldrk gS] ;s n”kkZus ds fy, geus fuEukuqlkj Statement }kjk secondValue Variable ds eku dks Change fd;k gS& secondValue = 60;

vxys Statement esa geus firstValue ls secondValue dk Reminder fudkyus ds fy, fuEukuqlkj Statement dk iz;ksx fd;k gS& remResult = firstValue % secondValue; main() Method ds vfUre Statement esa remResult Variable ds eku dks Output esa Print fd;k x;k gS] tks fd Output esa 40 Print djrk gSA ;fn ge secondValue Variable dk eku 60 Assign uk djrs] rks bl Statement }kjk izkIr gksus okyk ifj.kke 0 gksrkA D;ksafd firstValue ds eku 100 esa secondValue ds eku 50 dk Hkkx iwjk&iwjk pyk tkrk vkSj Reminder 0 cprkA


Java in Hindi blfy, geusa secondValue Variable dk eku Change djds 60 dj fn;kA blfy, gesa Output esa 40 izkIr gksrk gSA D;ksafd 100 esa 60 dk iwjk&iwjk Hkkx dsoy ,d gh ckj tkrk gS vkSj “ks’kQy 40 cprk gSA blh Program dks ;fn gesa ,d Applet }kjk Solve djuk gks] rks Applet ds fy, gesa fuEukuqlkj Coding djuh iMsxh% Name of File = AllArithmeticApplet.java import java.awt.*; import java.applet.*; public class AllArithmeticApplet extends Applet { int firstValue, secondValue; int addResult, subResult, mulResult, divResult, remResult; public void init() { firstValue = 100; secondValue = 50; addResult = firstValue + secondValue; subResult = firstValue - secondValue; mulResult = firstValue * secondValue; divResult = firstValue / secondValue; } public void paint(Graphics g) { g.drawString(firstValue+"+"+secondValue + " = " + addResult, 10, 20); g.drawString(firstValue+"-"+secondValue + " = " + subResult, 10, 40); g.drawString(firstValue+"*"+secondValue + " = " + mulResult, 10, 60); g.drawString(firstValue+"/"+secondValue + " = " + divResult, 10, 80); secondValue = 60; remResult = firstValue % secondValue;

}

}

g.drawString(firstValue+"%"+secondValue+ " = " + remResult, 10, 100);

Output


Java in Hindi

Example

,d ,slk Program cukvks ftlesa ,d lky esa lw;Z dh jks”kuh }kjk r; dh tkus okyh dqy nwjh Miles esa Output esa izkIr gksA pwafd lw;Z ds izdk”k dh xfr ,d Second esa 186000 gksrh gS] blfy, lw;Z ds izdk”k }kjk ,d lky esa r; dh tkus okyh xfr dk Formula fuEukuqlkj gksxk% Total Length = 186000 * 365 * 24 * 60 * 60 Program class LightDistance { public static void main( String args []) { int lightSpeed; long days; long seconds; long distance; //Approximate speed of light in miles per second lightSpeed = 186000;

}

}

days = 365; seconds = days * 24 * 60 * 60; //Convert to Seconds distance = lightSpeed * seconds; //Total Distance System.out.print("In " + days ); System.out.print(" days light will travel about "); System.out.println(distance + " miles");

Output In 365 days light will travel about 5865696000000 miles

bl Program esa geus System Class ds out Object ds fy, ,d u, Method print() dk iz;ksx fd;k gSA ;s method Bhd mlh izdkj ls dke djrk gS] ftl izdkj ls println() Method djrk gSA vUrj dsoy bruk gS fd println() Method Automatically New Line Provide djrk


Java in Hindi gS tcfd ;s Method New Line Provide ugha djrk gSA blhfy, geus rhu ckj System.out Object ds fy, Method dks Call fd;k gS] ysfdu ifj.kke gesa ,d gh Line esa izkIr gks jgk gSA bl Program esa geus long Data Type dk Variable Declare fd;k gSA geus ,slk blfy, fd;k gS D;ksafd 365 Days esa izdk”k ftruh nwjh r; djrk gS] og nwjh int izdkj ds Variable esa Store ugha fd;k tk ldrk gSA D;ksafd ;s nwjh int izdkj ds Data Type ds Variable dh Range ls T;knk gSA int izdkj dk Variable brus cMs eku dks Store ugha dj ldrk gSA blh rjg ls ge fofHkUu izdkj dh t:jrksa ds fy, fofHkUu izdkj ds Data Type ds Variables Declare dj ldrs gSa vkSj mUgsa Use dj ldrs gSaA

Variable Scope

tc ge tkok esa dksbZ Program fy[ks gSa rc ge Program esa fdlh Hkh LFkku ij dksbZ Variable Declare ugha dj ldrs gSaA lcls igys gesa ;s r; djuk gksrk gS fd gesa fdlh Variable dh t:jr dgka ij gSA ;s r; djuk blfy, t:jh gksrk gS D;ksafd gj Variable dk ,d Scope gksrk gS] tks ;s r; djrk gS fd fdlh Variable dks Program esa dc rd o dgka ls dgka rd Access fd;k tk ldrk gSA tkok esa fdlh Variable ds Scope dks mlds Block ls Identify fd;k tkrk gSA tks Variable ftl Block esa Declare fd;k tkrk gS] og Variable mlh Block rd mi;ksx fd;k tk ldrk gSA ml Block ls ckgj Variable dks Use ugha fd;k tk ldrk gSA ftl Variable dks tgka ij Declare fd;k tkrk gS] og Variable ogha ls Block ds vUr rd Visible jgrk gSA Variable uk rks Create ;k Declare gksus ls igys Visible jgrk gS vkSj uk gh Program Control ds Block ls ckgj fudyus ds ckn Visible jgrk gSA tSls gh Program Control fdlh Block ls ckgj fudyrk gS] ml Block ds lHkh Variables Destroy gks tkrs gSaA bl izfØ;k dks Programming esa Variable dk “Out Of Scope” gksuk dgrs gSaA

Code Block

Program Codes ds Statements dk og lewg ftls ,d Opening o Closing Curly Braces ( { } ) ds chp fy[kk tkrk gS] Statement Block ;k Code Block dgykrk gS vkSj lkekU;r;k bls dsoy Block dgrs gSaA Blocks dk iz;ksx lkekU;r;k Functions, Class, Loops vkfn esa fd;k tkrk gS] ftuds ckjs esa ge vkxs lh[ksaxsA

Type Casting

tkok dk Compiler bl fu;e ij dke djrk gS fd rHkh nks Operands ds chp fdlh izdkj dh Calculation gks ldrh gS] tc nksuksa Operands leku Data Type ds gksaA fofHkUu izdkj ds Binary Operators nks Operands ij izfØ;k djrs gSa vkSj ifj.kke Generate djrs gSaA ;fn Binary Operator ds nksuksa vksj leku Data Type ds Variables uk gksa] rks Compiler Lo;a gh Lower Data Type ds Variable ds eku dks nwljs Operand ds vuqlkj Higher Data Type ds eku esa Convert djrk gSA bl rjg dh Type Casting dks Automatic Type Casting dgrs gSaA mnkgj.k ds fy, fiNys Program ds fuEu Statement dks nsf[k,& distance = lightSpeed * seconds;

//Total Distance


Java in Hindi ge ns[k ldrs gSa fd lightSpeed Variable Integer izdkj dk Variable gS tcfd seconds long izdkj dk Variable gSA ;gka Integer izdkj ds Variable ds eku dk xq.kk long izdkj ds Variable ds eku ls gks jgk gS vkSj ifj.kke long izdkj ds Variable distance dks Assign gks jgk gSA bls Automatic Type Casting dgrs gSa] D;ksafd blesa Compiler Lo;a gh Integer izdkj ds Variable lightSpeed ds eku dks long izdkj ds eku esa Convert djus ds ckn nwljs long izdkj ds Variable seconds ds eku ls xq.kk djrk gS vkSj ifj.kke dks long izdkj ds Variable esa Store djrk gSA ;fn distance tks fd long izdkj dk Variable gS] float izdkj dk gksrk] rks Calculation ls izkIr gksus okyk ifj.kke float izdkj dk Return gksrk vkSj distance esa Float izdkj dk eku Store gksrk vkSj ;fn distance double izdkj dk Variable gksrk rks izkIr Resultant eku double izdkj esa Store gksrkA pwafd bl Statement esa Integer ls long esa ;kuh Lower Data Type ds eku dks Higher Data Type ds eku esa Convert djuk gS] blfy, ;s dke Compiler Automatically dj ysrk gSA ysfdu tc fdlh Higher Data Type ds eku dks Lower Data Type ds eku esa Convert djds Calculation djokuh gksrh gS] rc ge Automatic Type Casting dk iz;ksx ugha dj ldrs gSA

,slk djus ij ifj.kke xyr izkIr gksrk gSA bl fLFkfr esa gesa Manual Type Casting djuh iMrh gSA ;fn ge pkgsa fd blh Statement esa lightSpeed dk eku Long Data Type esa Convert gksus ds ctk;] seconds dk eku Integer izdkj esa Convert gks vkSj mlds ckn nksuksa Variables ds ekuksa dk xq.kk gks] rks gesa blh Statement dks fuEukuqlkj fy[kuk iMsxk& distance = lightSpeed * (int) seconds; //Total Distance

ge ns[k ldrs gSa fd seconds Variable ds igys ,d dks’Bd esa geus int Keyword dk iz;ksx fd;k gSA ;s Keyword seconds ds eku dks Integer izdkj ds eku esa Convert dj nsrk gSA pwafd dks’Bd dh Priority lHkh Operators o fofHkUu Language Symbols ls T;knk gksrh gS] blfy, lcls igys seconds dk eku long ls int esa Convert gksrk gSA mlds ckn lightSpeed o seconds ds ekuksa dk xq.kk gksrk gS] ftldk ifj.kke gesa Integer izdkj ds eku ds :i esa izkIr gksrk gSA ;s eku distance uke ds Variable esa Store gks tkrk gSA tgka rd gks lds gesa Higher Type ls Lower Type esa Data ds eku dks Convert ugha djuk pkfg,A ,slk djus ij Data dk Loss gks tkrk gSA tSls ;fn ge fdlh Integer izdkj ds eku 1234 dks char izdkj ds ;k byte izdkj ds eku esa Convert djsaxs] rks Data dk Loss gks tk,xkA D;ksafd byte izdkj dk Variable vf/kdre 256 rd dk eku gh Store dj ldrk gSA ;fn blls vf/kd eku dks bl izdkj ds Variable esa Store fd;k tkrk gS] rks izkIr gksus okyk ifj.kke viw.kZ ;k xyr gks tkrk gSA pfy,] Manual Type Casting dks le>us ds fy, ,d Example Program ns[krs gSaA Program public class ManualTypeCasting { public static void main(String args[]) { byte b;


Java in Hindi int i = 257; double d = 345.678; System.out.println("\n Conversion of int to byte. "); b = (byte) i; System.out.println("i and b " + i + " " + b); System.out.println("\n Conversion of double to int. "); i = (int) d; System.out.println("d and i " + d + " " + i);

}

}

System.out.println("\n Conversion of double to byte. "); b = (byte) d; System.out.println("d and b " + d + " " + b);

Output Conversion of int to byte. i and b 257 1 Conversion of double to int. d and i 345.678 345 Conversion of double to byte. d and b 345.678 89

tc Integer izdkj ds eku 257 dks byte izdkj esa Convert fd;k tkrk gS] rc gesa byte izdkj ds Variable dk eku 1 izkIr gksrk gSA ,slk blfy, gksrk gS D;ksafd Byte izdkj ds Variable esa dsoy 256 rd dk gh eku Store gks ldrk gS vkSj 256 rd dk eku Store djus ds fy, dsoy 8-Bits dh t:jr gksrh gSA tcfd 257 eku dks Store djus ds fy, gesa de ls de 9Bits dh t:jr gksrh gS vkSj 257 dh Binary 100000001 gksrh gSA vc pwafd Byte izdkj ds Variable esa dsoy 8 Bits gh Store gks ldrs gSa] blfy, Byte izdkj ds Variable esa 00000001 Bits gh Stored gks ikrs gSa 9 osa LFkku dk Bit Lost gks tkrk gSA bl fLFkfr esa ;s Bits eku 1 dks Represent djrs gSaA tc double izdkj ds eku dks int izdkj ds eku esa Convert fd;k tkrk gS] dk Variable nleyo ds ckn ds eku dks Store ugha dj ldrk gS] blfy, ds eku dks int izdkj esa Convert fd;k tkrk gS] rc double izdkj ds nleyo okys Hkkx dks Compiler }kjk NksM fn;k tkrk gS vkSj int izdkj ds 345 gh Store gks ikrk gSA

rc pwafd int izdkj tc double izdkj eku 345.678 ds Variable esa dsoy

tc double izdkj ds eku dks byte izdkj ds Variable esa Store djus ds fy, Convert fd;k tkrk gS] rc double izdkj ds Variable ds nleyo okyk fgLlk Compiler }kjk NksM fn;k tkrk gSA fQj pwafd byte izdkj dk Variable dsoy 256 rd ds eku dks gh Store dj ldrk gS] blfy, double izdkj ds eku 345 esa ls 256 Less gks tkrk gS vkSj 89 cprk gSA ;s 89 eku byte izdkj ds Variable esa Store gks tkrk gSA


Java in Hindi tkok Type Checking ds ekeys esa cgqr gh Strict gSA ge fdlh byte izdkj ds Variable esa int izdkj ds eku dks Store djuk pkgrs gSa] rks tkok gesa ,slk ugha djus nsrk gSA ;fn gesa byte izdkj ds Variable es int izdkj ds Variable dk eku Assign djuk gks] rks gesa int izdkj ds Variable dh Type Casting djuh gh iMrh gSA tSls% int i; byte b; b = (int) i;

Arrays

;s ,d Secondary Data Type gSA tc gesa Computer esa dsoy ,d eku dks Store djuk gksrk gS] rc ge ml eku ds Data Type ds vuqlkj ,d Variable Create dj ysrs gSaA ysfdu tc gesa ,d gh izdkj Data Type ds ,d ls vf/kd ekuksa dks ,d gh Variable ds :i esa Computer esa Store o Manage djuk gksrk gS] rc ge Array dk iz;ksx djrs gSaA mnkgj.k ds fy, ekuyks fd gesa dsoy ,d Student dk Roll Number Computer esa Store djuk gS] rks ge fuEukuqlkj ,d Variable Declare dj ldrs gSa& int rollNumber;

ysfdu ;fn gesa 100 Students ds Roll Number dks Computer esa Store djuk gks vkSj ge blh lkekU; rjhds dk iz;ksx djsa] rks gesa fuEukuqlkj 100 Variables Create djus gksaxs& int rollNumber1; int rollNumber2; int rollNumber3; int rollNumber4; int rollNumber5; . . . . . .

int rollNumber99; int rollNumber100; Array ,d ,slh O;oLFkk gS tks blh dke dks ,d gh Statement }kjk dj nsrk gSA blds fy, gesa Bracket Symbol ( [ ] ) dk fuEukuqlkj iz;ksx djuk gksrk gS& int rollNumber[];

ge bl Bracket Symbol dks Variable ds uke ds igys Hkh fy[k ldrs gSaA ;kuh int []rollNumber;

;fn gesa nks Array Create djus gksa vkSj ge Bracket Symbol dks Variable ds uke ds ckn esa fy[ksa] rks gesa Array dk Declaration fuEukuqlkj djuk gksxk&


Java in Hindi int rollNumber[], serialNumber[];

tcfd ;fn ge bl Bracket Symbol dks Data Type ds Just ckn esa fy[krs gSa] rks gesa gj Variable ds uke ds ckn Bracket Symbol dk iz;ksx djus dh t:jr ugha gksrh gSA ;kuh ge blh dke dks fuEukuqlkj Hkh dj ldrs gSa& int [ ] rollNumber, serialNumber;

;fn ge pkgsa fd dqN Variable dsoy lkekU; Variables gksa vkSj dqN Array gksa rks ge fuEukuqlkj Statement fy[k ldrs gSa& int contactNumber, [] rollNumber, serialNumber;

bl Statement esa contactNumber ,d gh Variable gksxk tcfd rollNumber o serialNumber nks Array gSaA Array Memory Allocation lHkh Primary Type ds Variables Declare djrs gh mUgsa Java dk Compiler Memory Allocate dj nsrk gS] ysfdu tc ge dksbZ Array Create djrs gSa] rc gesa ,d vyx Statement }kjk Array ds fy, Memory Allocate djuh iMrh gS vkSj ;s crkuk iMrk gS fd ge fdrus eku Store djuk pkgrs gSaA ;gka ge ;fn 100 Students ds fy, Memory Allocate djuk pkgsa rks gesa fuEukuqlkj new Operator dk iz;kssx djrs gq, Statements fy[kus gksaxs& int rollNumber[] = new int[100];

;fn ge “C” ;k “C++” dh rjg Java esa Array dk Declaration djsa] rks Java Error nsrk gSA ;kuh int rollNumber[100];

;s Statement “C” o “C++” esa dke djrk gS ysfdu Java esa Error nsrk gSA

Array Initialization ge tc fdlh Variable dks Create djrs gSa] rks Variable Create djrs le; gh mls igyk izkjfEHkd eku iznku dj ldrs gSaA bl izfØ;k dks Initialization dgrs gSaA tSls int serialNumber = 131200;

blh rjg ls ge tkok esa fdlh Array dks Hkh Initialize dj ldrs gSaA Java esa fdlh Array dks fuEukuqlkj Initialize fd;k tk ldrk gS& int intArray[] = {1,2,3,4,5}; char [] charArray = {'a', 'b', 'c'}; 122 Any Question or Suggestion, Just Discuss Here...

Java in Hindi string [] stringArray = {"A", "Four", "Element", "Array"};

tc ge bl izdkj ls fdlh Array dks Declare djrs gSa rc Array dh Size Lo;a gh Initialize fd, x, ekuksa dh la[;k ds vk/kkj ij r; gks tkrh gSA mnkgj.k ds fy, igys Statement ds Array intArray dh Size 5 gksxh] nwljs Array charArray dh Size 3 vkSj rhljs Statement stringArray dh Size 4 gksxhA lHkh vU; Hkk’kkvksa dh rjg gh Java esa Hkh ge 2-Dimesional o Multi-Dimensional Array Create dj ldrs gSaA ,slk djus ds fy, gesa dsoy Brackets dh la[;k dks c
ge Java esa nks rjhdksa ls ;s dke dj ldrs gSaA bu nksuksa rjhdksa dks mijksDr Statements esa crk;k x;k gSA ;fn ge Multidimensional Array Create djuk pkgsa] rks fuEukuqlkj dj ldrs gSa% float floatArray[][][]; floatArray = new float[10][5][10]; double [][][] doubleArray = new double[10][10][10];

fdlh 2-D ;k Multi-D Array ds Brackets esa fn, tkus okys lHkh ekuksa dks ;fn vkil esa xq.kk dj fn;k tk,] rks feyus okyh la[;k ml Array esa dqy Store gks ldus okys ekuksa dh la[;k dks Represent djrk gSA tSls doubleArray Memory esa 10 * 10 * 10 = 1000 Double Data Type ds ekuksa dks Store dj ldrk gSA ekuyks fd geus fuEukuqlkj ,d Statement }kjk nl ukeksa dks Store djus ds fy, Array Create fd;k% String name = new String[6];

;s Statement okLro esa ,d gh le; esa 6 Variables Create djrk gS vkSj lHkh Variables dk uke leku gksrk gSA bu fofHkUu Variables dks ge Variable ds Index Number ls igpkurs gSaA tkok esa Index Number ,d ,slk Number gksrk gS] tks ,d gh izdkj ds ukeksa esa fofHkUurk ykus ds fy, Use fd;k tkrk gSA pwafd ge ,d gh Program ds leku Scope esa ,d gh uke ds dbZ Variables Create ugha dj ldrs gSaA blfy, Compiler Lo;a gh ,d lkFk ,d gh uke ls Create gksus okys fofHkUu Variables dh igpku ds fy, muds lkFk ,d Number tksM nsrk gSA bl Number dks Index Number dgrs gSa vkSj bldh “kq:vkr gesa”kk 0 ls gksrh gSA gekjs Statement esa geus 6 ukeksa dks Store djus ds fy, Memory Reserve dh gSA bl Statement }kjk fuEukuqlkj name uke ds 6 Variables Create gksrs gSa%


Java in Hindi name[0] name[1] name[2] name[3] name[4] name[5]

vc ;fn ge bu Variables esa uke Assign djuk pkgsa rks fuEukuqlkj dj ldrs gSa& name[0] = “Balaji” ; name[1] = “Madhav” ; name[2] = “BalGopal” ; name[3] = “Nandlal” ; name[4] = “BalKishan” ; name[5] = “ManMohan” ;

vc ;fn ge bl Array ds fofHkUu Index Number ij Stored ukeksa dks Output esa Print djuk pkgsa] rks fuEukuqlkj Statements }kjk dj ldrs gSa% System.out.println("Name in Array at Index Number [0] = " + name[0]); System.out.println("Name in Array at Index Number [1] = " + name[1]); System.out.println("Name in Array at Index Number [2] = " + name[2]); System.out.println("Name in Array at Index Number [3] = " + name[3]); System.out.println("Name in Array at Index Number [4] = " + name[4]); System.out.println("Name in Array at Index Number [5] = " + name[5]);

bl iwjs Program dks ge fuEukuqlkj fy[k ldrs gSa& Program public class Array { public static void main(String args[]) { String name[] = new String[6]; name[0] = "Balaji" ; name[1] = "Madhav" ; name[2] = "BalGopal" ; name[3] = "Nandlal" ; name[4] = "BalKishan" ; name[5] = "ManMohan" ; System.out.println("Name in Array at Index Number [0] = " + name[0]); System.out.println("Name in Array at Index Number [1] = " + name[1]); System.out.println("Name in Array at Index Number [2] = " + name[2]); System.out.println("Name in Array at Index Number [3] = " + name[3]); System.out.println("Name in Array at Index Number [4] = " + name[4]); System.out.println("Name in Array at Index Number [5] = " + name[5]); } }


Java in Hindi Output Name in Array at Index Number [0] = Balaji Name in Array at Index Number [1] = Madhav Name in Array at Index Number [2] = BalGopal Name in Array at Index Number [3] = Nandlal Name in Array at Index Number [4] = BalKishan Name in Array at Index Number [5] = ManMohan

;fn ge blh Program dks Applet ds :i esa cukuk pkgsa rks bl dke dks djus ds fy, gesa fuEukuqlkj Applet Program fy[kuk gksxk% Program File Name : ArrayApplet.java import java.awt.*; import java.applet.*; public class ArrayApplet extends Applet { String name[] = new String[6]; public void init() { name[0] = "Balaji" ; name[1] = "Madhav" ; name[2] = "BalGopal" ; name[3] = "Nandlal" ; name[4] = "BalKishan" ; name[5] = "ManMohan" ; }

}

public void paint(Graphics g) { g.drawString("Name in Array at Index Number[0]="+name[0],30,20); g.drawString("Name in Array at Index Number[1]="+name[1],30,40); g.drawString("Name in Array at Index Number[2]="+name[2],30,60); g.drawString("Name in Array at Index Number[3]="+ name[3],30,80); g.drawString("Name in Array at Index Number[4]="+name[4],30,100); g.drawString("Name in Array at Index Number[5]="+ name[5],30,120); }

Output


Java in Hindi

blh rjg ls ge ,d 2-D o Multi-D Array dks Hkh Use dj ldrs gSaA ekuyks fd gesa ,d 2-D Array esa fuEu Table ds ekuksa dks Store djuk gS& 10 50 2 93

20 46 12 39

30 20 30 3

ge ns[k ldrs gSa fd bl Table esa pkj Row o rhu Columns gSa] blfy, gesa fuEukuqlkj [4][3] dk Array Create djuk gksxk% int Table = new int[4][3];

;fn ge bl Table ds fofHkUu ekuksa dks Initialize djuk pkgsa rks igys gesa ;s le>uk gksxk fd bl Array dks Memory esa fdl izdkj ls Represent fd;k tk ldrk gSA ftl rjg ls Table fn[kkbZ ns jgh gS] mlh rjg ls fofHkUu Index Numbers Hkh Set gksrs gSaA ;fn ge mijksDr Tables ds fofHkUu ekuksa ds Index Numbers dks Represent djuk pkgsa] rks fuEukuqlkj dj ldrs gSa& [0][0] [1][0] [2][0] [3][0]

[0][1] [1][1] [2][1] [3][1]

[0][2] [1][2] [2][2] [3][2]

ge le> ldrs gSa fd Table ds izFke Row izFke Column dk eku Index Number [0][0] ij Store gksrk gSA Table ds nwljs Row ds nwljs Column dk eku Index Number [1][1] ij Store gksrk gSA ;kuh ;fn ge pkgsa rks mijksDr Table ds fofHkUu ekuksa dks fuEukuqlkj Statement }kjk Memory esa Store dj ldrs gSa& Table[0][0] = 10 ; Table[0][1] = 20 ; Table[0][2] = 30 ; Table[1][0] = 50 ; Table[1][1] = 46 ; Table[1][2] = 20 ; Table[2][0] = 2 ; Table[2][1] = 12 ;


Java in Hindi Table[2][2] = 30 ; Table[3][0] = 93 ; Table[3][1] = 39 ; Table[3][2] = 3 ;

;fn ge bls Program ds :i esa n”kkZuk pkgsa rks fuEukuqlkj n”kkZ ldrs gSa& Program public class Table { public static void main(String args[]) { int table[][] = new int[4][3]; table[0][0] = 10 ; table[0][1] = 20 ; table[0][2] = 30 ; table[1][0] = 50 ; table[1][1] = 46 ; table[1][2] = 20 ; table[2][0] = 2 ; table[2][1] = 12 ; table[2][2] = 30 ; table[3][0] = 93 ; table[3][1] = 39 ; table[3][2] = 3 ;

}

}

System.out.println("Value in Array at Index Number [0][0] = " +table[0][0]); System.out.println("Value in Array at Index Number [0][1] = " +table[0][1]); System.out.println("Value in Array at Index Number [0][2] = " +table[0][2]); System.out.println("Value in Array at Index Number [1][0] = " +table[1][0]); System.out.println("Value in Array at Index Number [1][1] = " +table[1][1]); System.out.println("Value in Array at Index Number [1][2] = " +table[1][2]); System.out.println("Value in Array at Index Number [2][0] = " +table[2][0]); System.out.println("Value in Array at Index Number [2][1] = " +table[2][1]); System.out.println("Value in Array at Index Number [2][2] = " +table[2][2]); System.out.println("Value in Array at Index Number [3][0] = " +table[3][0]); System.out.println("Value in Array at Index Number [3][1] = " +table[3][1]); System.out.println("Value in Array at Index Number [3][2] = " +table[3][2]);

Output Value in Array at Index Number [0][0] = 10 Value in Array at Index Number [0][1] = 20 Value in Array at Index Number [0][2] = 30 Value in Array at Index Number [1][0] = 50 Value in Array at Index Number [1][1] = 46 Value in Array at Index Number [1][2] = 20


Java in Hindi Value in Array at Index Number [2][0] = 2 Value in Array at Index Number [2][1] = 12 Value in Array at Index Number [2][2] = 30 Value in Array at Index Number [3][0] = 93 Value in Array at Index Number [3][1] = 39 Value in Array at Index Number [3][2] = 3

blh rjg ls ;fn ge pkgsa rks Multi-D Array Hkh Create dj ldrs gSa vkSj mlds fofHkUu Index Numbers ij fofHkUu Data Items dks Store dj ldrs gSaA ;fn ge fdlh 2-D Array dks Create djrs le; gh mls Initialize djuk pkgsa] rks ;s dke ge fuEukuqlkj dj ldrs gSa& int table[][] = {{1,2,3},{4,5,6},{7,8,9},{12,21,12}};

;fn ge pkgsa] rks mijksDr Program dks fuEukuqlkj Modify dj ldrs gSa& Program public class Table1{ public static void main(String args[]){ int table[][] = {{1,2,3},{4,5,6},{7,8,9},{12,21,12}}; System.out.println("Value in Array at Index Number [0][0] = " +table[0][0]); System.out.println("Value in Array at Index Number [0][1] = " +table[0][1]); System.out.println("Value in Array at Index Number [0][2] = " +table[0][2]); System.out.println("Value in Array at Index Number [1][0] = " +table[1][0]); System.out.println("Value in Array at Index Number [1][1] = " +table[1][1]); System.out.println("Value in Array at Index Number [1][2] = " +table[1][2]); System.out.println("Value in Array at Index Number [2][0] = " +table[2][0]); System.out.println("Value in Array at Index Number [2][1] = " +table[2][1]); System.out.println("Value in Array at Index Number [2][2] = " +table[2][2]); System.out.println("Value in Array at Index Number [3][0] = " +table[3][0]); System.out.println("Value in Array at Index Number [3][1] = " +table[3][1]); System.out.println("Value in Array at Index Number [3][2] = " +table[3][2]); } } Output Value in Array at Index Number [0][0] = 1 Value in Array at Index Number [0][1] = 2 Value in Array at Index Number [0][2] = 3 Value in Array at Index Number [1][0] = 4 Value in Array at Index Number [1][1] = 5 Value in Array at Index Number [1][2] = 6 Value in Array at Index Number [2][0] = 7 Value in Array at Index Number [2][1] = 8 Value in Array at Index Number [2][2] = 9 Value in Array at Index Number [3][0] = 12 Value in Array at Index Number [3][1] = 21 Value in Array at Index Number [3][2] = 12


Java in Hindi T;knkrj gesa 2-D Array dh gh t:jr iMrh gSA Multi-D Array dh t:jr gh ugha gksrh gSA fQj Hkh ;fn Multi-D Array dh t:jr iMs rks mls Hkh blh izdkj ls Create o Initialize fd;k tkrk gSA fdlh Hkh Array dh Size gesa”kk length uke ds ,d Object esa Store gksrh gSA ;fn gesa fdlh Array X[ ] dh Size irk uk gks] rks ge bl Array X[ ] dh Size dks fuEukuqlkj Kkr dj ldrs gSa& int sizeOfArray = X.length

;s Statement sizeOfArray uke ds Integer izdkj ds Variable esa X uke ds Array dh dqy Size dks Store dj nsrk gSA tkok ,d Multi Dimensional Array dks “Array of Arrays” dh rjg Treat djrk gSA ;kuh fdlh 2-D Array dks ge fuEukuqlkj Hkh Declare dj ldrs gSa& int info[][] = new int [3][]; info[0] = new int[2]; info[1] = new int[5]; info[2] = new int[3];

bl izdkj dk Declaration fuEukuqlkj Variable Size dk 2-D Array Create djrk gS&

Strings

Character izdkj ds Data Type dk Variable Memory esa dsoy ,d Character dks gh Store dj ldrk gSA “C” o “C++” esa Hkh char Data Type dsoy ,d gh Character dks Store djrk gSA ;fn gesa fdlh Student dk uke Computer esa Store djuk gks] rks “C” o “C++” esa Characters dk ,d Array cukuk iMrk gS] tcfd Java esa ,slk djus dh t:jr

ugha gSA

ge String izdkj ds Data Type dk iz;ksx djds ,d Variable Create dj ldrs gSa vkSj bl Variable }kjk fdlh Student ds uke dks Computer esa Store dj ldrs gSaA gkykafd Java esa Strings (Characters ds ,d iwjs lewg) dks Store djus ds fy, dksbZ Hkh Primary Data Type ugha gS] ysfdu Java esa Strings dks Computer esa Store djus ds fy, Java ds ,d String Class ds Object ds :i esa gesa Variable Declare djuk iMrk gS vkSj bl String Class (Data Type) ds Object (Variable) ds vUnj ge fdlh String dks Store dj ldrs gSaA tSls% String nameOfStudent;


Java in Hindi String Manipulation dbZ tkok Programs dk lcls Common dke gSA String Characters dh ,d Sequence dks Represent djrk gS] ftls ge ,d 1-D Array ds :i esa fuEukuqlkj Represent dj ldrs gSa& char name[] = new char[4]; name[0] = ‘K’; name[1] = ‘a’; name[2] = ‘w’; name[3] = ‘a’;

gkykafd Character Array gesa ;s lqfo/kk iznku djrk gS fd ge Array ds fofHkUu Characters dks Query djds Array dh Length dk irk yxk ldrs gSaA ysfdu dbZ String Operations ds fy, ;s Characters dk Array gesa i;kZIr lqfo/kk iznku ugha djrk gSA tSls ;fn ,d String dks nwljh String esa Copy djuk gks rks ,d Array ls gj Character dks Read djds nwljs Array esa Øe”k% Write djuk] ,d lqfo/kktud dke ugha gks ldrk gSA blds fy, gesa dkQh Extra dke djuk ;k Coding djuh iMrh gSA bl izdkj dh fLFkfr;ksa ls cpus ds fy, tkok esa String Object dks Use fd;k tkrk gSA tkok esa Strings ,d Class gS ftls nks Classes “String” o “StringBuffer” dks Use djds Implement fd;k tkrk gSA Java String tkok dh String Class dk ,d Instance ;k Object gksrk gS vkSj “C” ds String (1-D Character Array) dh rqyuk esa dkQh Reliable gksrk gSA tkok dh String ,d Null Terminated String ugha gksrh gS uk gh og ,d 1-D Character Array gksrk gSA bl Strings dks fuEukuqlkj Declare o Create fd;k tk ldrk gS% String stringName; stringName = new String(“String”); Array dh rjg gh String dh Hkh Length dks String Class ds length Method }kjk izkIr

fd;k tk ldrk gSA tSls

int m = name.length();

tkok String dks ge + Operator dk iz;ksx djds vkil esa fuEukuqlkj tksM ldrs gSa& String firstName, lastName; String fullName = firstName + lastName String City = “New” + “Maharastra”;

ge Strings dk Hkh mlh izdkj ls Array Create djds Use dj ldrs gSa ftl izdkj ls fdlh Integer izdkj ds Array dks Use djrs gSAa tSls String name = new String[3];

;s Statement name uke ds rhu String Variable Memory esa Create djsxk] ftuds Index Numbers vyx&vyx gksaxs vkSj gj Variable Memory esa ,d String dks Store dj ldsxkA ukeksa dks Memory esa Store djus ds fy, ge for Loop dk iz;ksx dj ldrs gSaA


Java in Hindi String Methods String Class esa dbZ Methods dks Define fd;k x;k gS] tks fofHkUu izdkj ds String Manipulation dkeksa dks lEHko cukrs gSaA String Objects o Methods dk iz;ksx GUI Programs esa cgqr gh General :i esa fd;k tkrk gSA lkekU;r;k fdlh GUI Program tSls fd Applet Window esa fLFkr fdlh Text Box esa User tks dqN Hkh Input djrk gS] og lcdqN String ds :i esa gh gksrk gSA ;kuh fdlh Text Box esa User pkgs Texts Input djs ;k Number] Text Box esa User tks Hkh dqN Input djrk gS] og lcdqN String gh gksrk gSA ;gka ij ge dqN String Manipulation Methods dks Describe dj jgs gSa] ftudk iz;ksx fofHkUu izdkj ds String Manipulation Operations dks Perform djus ds fy, fd;k tk ldrk gSA String string1 = new String(“ Rahul ”); String string2 = new String(); string2 = string1.toLowerCase; ;s Statement string1 ds lHkh Characters dks Lowercase Letters esa Convert dj nsrk gSA bldk Output fuEukuqlkj izkIr gksrk gS& “ rahula

“

string2 = string1.toUpperCase; ;s Statement string1 ds lHkh Characters dks Uppercase Letters esa Convert dj nsrk gSA bldk Output fuEukuqlkj izkIr gksrk gS& “ RAHUL “ string2 = string1.replace(‘a’, ‘i'); ;s Statement string1 esa fLFkr lHkh ‘a’ Characters ds LFkku ij Character ‘i’ dks Replace dj nsrk gSA bldk Output fuEukuqlkj izkIr gksrk gS& “ Rihul “ string2 = string1.trim(); ;s Statement string1 ds igys vkSj ckn esa vk, gq, lHkh White Space Characters dks Remove dj nsrk gSA bldk Output fuEukuqlkj izkIr gksrk gS& “Rihul“


Java in Hindi String1.equals(strin2); ;fn nksuksa Strings Objects esa leku String gks rks ;s Statement true Return djrk gSA mnkgj.k ds fy, ;fn string1 = “Rahul” gks vkSj string2 = “Rahul” gks] rks ;s Statement true Return djsxkA String1.equalsIgnoreCase(strin2); ;fn nksuksa Strings Objects esa leku String gks rks ;s Statement true Return djrk gS] tcfd nksuksa String dk Case pkgs vyx gh D;ksa uk gksA mnkgj.k ds fy, ;fn string1 = “Rahul” gks vkSj string2 = “rahul” gks rks Hkh ;s Statement true gh Return djsxkA string1.length(); ;s Statement string1 dh length Return djrk gSA ;fn string = “Rahul” gks rks ;s Statement 5 Return djrk gS] D;ksafd bl String esa ikap Characters gSaA string1.chartAt(n); ;s Statement string1 dh nth Location ds Character dks Return djrk gSA ;kuh ;fn string1 = “Madhav” gks vkSj n = 3 gks rks ;s Statement ‘d’ Return djrk gSA string1.compareTo(string2); ;s Statement ;fn string1 < string2 gks rks Negative Value, ;fn string1 > string2 gks Positive Value vkSj ;fn nksuksa Strings ,d leku gks rks Zero Return djrk gSA string1.concat(string2); ;s Statement string1 dks string2 ls tksM nsrk gSA string1.substring(n); ;s Statement string1 dh n Location ds Character ds lkFk n Location ds Character ls vkxs dh Sub String Return djrk gSA string1.substring(n, m); ;s Statement string1 dh n Location ds Character ds lkFk n Location ds Character ls vkxs vkSj m Location ds Character ls igys rd dh Sub-String Return djrk gSA String.ValueOf(m); ;s Statement Parameter m ds fy, ,d String Object Create djrk gSA m.toString(); ;s Statement Object m dks String Representation esa Convert djds Return djrk

gSA


Java in Hindi string1.indexOf(‘b’); ;s Statement String1 ds igys ‘b’ Character ds Index Number dks Return djrk gSA string1.indexOf(‘b’, n); ;s Statement String1 ds n Characters ds ckn igys ‘b’ Character ds Index Number dks Return djrk gSA String.ValueOf(ValueM); ;s Statement Parameter ValueM dks String Representation esa Convert djds Return djrk gSA

buesa ls dqN String Methods dks ge ,d Applet Program esa Use djds mldk Output ns[k ldrs gSaA Applet Program dks fuEukuqlkj Develop fd;k tk ldrk gS% Program // Source File : StringMethodApplet.java // Compiled File: StringMethodApplet.Class // Imports import java.applet.*; import java.awt.*; public class StringMethodApplet extends Applet { TextField textBox = new TextField(40); String str; public void init() { add(textBox); } public void paint(Graphics g) { boolean yes; char characterAtPosition; int strLength; str = textBox.getText(); str = str.toLowerCase(); g.drawString("toLowerCase Method : " + str, 20, 80); str = str.toUpperCase(); 133 Any Question or Suggestion, Just Discuss Here...

Java in Hindi g.drawString("toUpperCase Method : " + str, 20, 60); str = str.trim(); g.drawString("trim Method : " + str, 20, 100); yes = str.equals("Man Mohan"); g.drawString("equals Method : " + yes, 20, 140); yes = str.equalsIgnoreCase("Man Mohan"); g.drawString("equals Method : " + yes, 20, 160); str = str.replace('a', 'i'); g.drawString("replace Method : " + str, 20, 120); strLength = str.length(); g.drawString("length Method : " + strLength, 20, 180); characterAtPosition = str.charAt(4); g.drawString("charAt Method : " + characterAtPosition, 20, 200); strLength = str.compareTo("Man Mohan"); g.drawString("compareTo Method : " + strLength, 20, 220); str = str.concat(" Lal"); g.drawString("concat Method : " + str, 20, 240);

}

}

str = String.valueOf(1000); g.drawString("String.valueOf Method : " + str, 20, 260);


Output


Java in Hindi

GUI esa fdlh Number dks Display djuk gks ;k fdlh Character dks] nksuksa dks gh String Format esa gh Display djuk iMrk gSA fdlh Numerical eku dks Text Format ;k String Format esa Convert fd, fcuk ge mls GUI Application Window ;k fdlh Applet ij Display ugha dj ldrs gSaA

blfy, tc gesa fdlh Applet esa fdlh Numerical eku dks Display djuk gksrk gS] rc ml eku dks Display djus ls igys gesa ml eku dks String Object esa Convert djuk t:jh gksrk gSA fdlh Numerical eku dks String Object esa Convert djus ds fy, gesa String Class ds valueOf() Method dk iz;ksx djuk iMrk gS vkSj ftl eku dks String esa Convert djuk gksrk gS] ml eku dks Argument ds :i esa valueOf() Method ds Parenthesis esa nsuk gksrk gSA fiNys Program esa eku 1000 dks geus blh rjhds ls Applet ij Display fd;k gSA blh rjg ls compareTo() String Method dk iz;ksx djds ge Strings ds Array dh Sorting dj ldrs gSaA Program class StringSorting { static String name[] = { "Madhav", "Krishna", "Kanhaiya", "Balgopal", "Nandlal" }; public static void main(String args[])


Java in Hindi {

}

int size = name.length; String temp = null; for(int i = 0; i < size; i++) { for(int j = i+1; j < size; j++) { if(name[j].compareTo(name[i]) < 0) { //swap the strings temp = name[i]; name[i] = name[j]; name[j] = temp; } } } for( int i = 0; i
Output Balgopal Kanhaiya Krishna Madhav Nandlal

bl Program esa for() Loop dk iz;ksx fd;k x;k gSA Looping ,d Control Statement gS] ftlds ckjs esa ge vxys v/;k; esa i
StringBuffer Class

StringBuffer String Class dh ,d Peer Class gSA ;kuh String Class Fixed_Length dh String Object Create djrk gS] tcfd StringBuffer Flexible Length dk String Object Create djrk gS] ftlds Contents o Length nksuksa dks Modify fd;k tk ldrk gSA

bl Object dh String ds chp esa ge ubZ String Insert dj ldrs gSa lkFk gh fdlh ubZ String dks bl String Object dh String ds End esa Append Hkh dj ldrs gSaA blds Object ds lkFk ge fuEu String Methods dks Use dj ldrs gSa tks fd lokZf/kd Use fd, tkrs gSa& string1.setChartAt(n, ‘p’) ;s Statement string1 ds nth Character dks Modify djds ‘p’ dj nsrk gSA string1.append(string2)


Java in Hindi ;s Statement string2 ds vUr esa string1 dks Append dj nsrk gSA string1.insert(n, string2) ;s Statement string1 ds nth Character ij string2 dks Insert dj nsrk gSA string1.setLength(n) ;s Statement string1 dh length dks n ds cjkcj Set dj nsrk gSA ;fn nString 1.length gks rks string1 esa zeros Add gks tkrs gSaA

bUgsa Use djrs gq, ge fuEukuqlkj ,d Program cuk ldrs gSa& Program class StringManipulation { public static void main(String args[]) { StringBuffer string1 = new StringBuffer("OOPS with JAVA"); System.out.println("Original String : " + string1); //Obtaining string length System.out.println("Length of String : " + string1.length()); //Accessing characters of string for(int i=0; i
}

}

//Appending a string at the end string1.append(" Programming"); System.out.println("Appended string : " + string1);

Output 137 Any Question or Suggestion, Just Discuss Here...

Java in Hindi Original String : OOPS with JAVA Length of String : 14 Character at position : 1 is O Character at position : 2 is O Character at position : 3 is P Character at position : 4 is S Character at position : 5 is Character at position : 6 is w Character at position : 7 is i Character at position : 8 is t Character at position : 9 is h Character at position : 10 is Character at position : 11 is J Character at position : 12 is A Character at position : 13 is V Character at position : 14 is A Modified string : OOPS Concepts with JAVA String now : OOPS C_ncepts with JAVA Appended string : OOPS C_ncepts with JAVA Programming

Command Line Arguments

dbZ ckj ,slh ifjfLFkfr;ka gksrh gSa fd tc ge pkgrs gSa fd gekjk Program Command Prompt ij gekjs }kjk fn, x, Input ds vk/kkj ij fofHkUu izdkj ds Operations Perform djsA fdlh izksxzke ls ;s fof”k’Vrk izkIr djus ds fy, gesa ,d ,sls tkok Concept dks Use djuk gksrk gS] ftls Command Line Arguments dgrs gSaA Command Line Arguments os eku gksrs gSa] tks fdlh Program dks Command Prompt ij Run djrs le; Parameters ds :i esa Program dks iznku fd, tkrs gSaA mnkgj.k ds fy, tc ge fuEukuqlkj Hello World Program dks Run djrs gSa % C:jdk\bin\> java HelloWorld

rc ;gka ge HelloWorld Program dks fdlh izdkj dk dksbZ Argument Pass ugha dj jgs gSaA ge ;gka ;fn Arguments Pass Hkh djrs gSa] rks Hkh HelloWorld Program dks ;s irk ugha gksrk gS] fd Supply fd, tkus okys Command Line Arguments ds lkFk D;k izfØ;k djuh gSA ge ,sls tkok Programs fy[k ldrs gSa tks Command Line ij iznku fd, x, Arguments dks Use dj ldrk gS vkSj Arguments ds vk/kkj ij fofHkUu izdkj ds Output iznku dj ldrk gSA bls le>us ds fy, main() Method ds Structure dks nsf[k, % public static void main(String args[])


Java in Hindi ge ns[k ldrs gSa fd main() Method esa args dks ,d Strings ds Array izdkj dk Declare fd;k x;k gS] tks fd String Objects dks Store dj ldrk gSA Program ds Execution ds nkSjku ;fn Command Prompt ij dksbZ Hkh Argument iznku fd;k tkrk gS] rks Command Line ij fn, tkus okys lHkh Argument dk eku args uke ds bl Object esa String Object ds :i esa Store gks tkrk gSA main() Method esa ge args Array ds fofHkUu Objects dks Array Elements ds :i esa Access dj ldrs gSa vkSj fofHkUu izdkj ds Manipulations dj ldrs gSaA mnkgj.k ds fy, eku yks fd ge Command Prompt ij HelloWorld Program dks fuEukuqlkj Interpret djrs gSa% C:jdk\bin\> java HelloWorld Madhav Raghav Nandlal Madan Gopal

rks args Array ds fofHkUu Elements ds :i esa ;s Objects fuEukuqlkj Store gks tkrs gSa& Madhav Raghav Nandlal Madan Gopal

    

args[0] args[1] args[2] args[3] args[4]

vc ;fn ge args[3] dks Program esa fdlh izdkj ls Use djuk pkgsa] rks args[3] esa vkus okyk eku Command Prompt ls vk,xk] ftls Handle djus ds fy, ge igys ls gh Codlings fy[k ldrs gSaA bl Concept ds vk/kkj ij ge fuEukuqlkj ,d Program Develop dj ldrs gSa% Program class CmdLineParameters { public static void main(String args[]) { int count, i=0; String string; count = args.length; System.out.println("\nNumber of arguments = " +count+ "\n"); while( i
bl Program dks Compile djds tc ge fuEukuqlkj Command Line Arguments ds lkFk Run djrs gSa] rc gesa vxzkuqlkj ifj.kke izkIr gksrk gS % C:jdk\bin\>java CmdLineParameters Madhav Mohan Manmohan Madan Nandlal Balgopal Gopal


Java in Hindi Output Number of arguments = 7 args[0] : Madhav args[1] : Mohan args[2] : Manmohan args[3] : Madan args[4] : Nandlala args[5] : Balgopal args[6] : Gopal

bl Program esa Command Line Arguments dh dqy la[;k dks Kkr djus ds fy, geusa length Method dks Use fd;k gSA bl Method dk iz;ksx fdlh Hkh Array dh Size Kkr djus ds fy, fd;k tk ldrk gSA tkok ,d Freeform Language gSA ;kuh tkok dk Program fy[krs le; ;s t:jh ugha gksrk gS fd tkok ds gj Line ds Codes dks Indent djds ,d gh Form esa j[kk tk,A tkok dks bl ckr ls dksbZ QdZ ugha iMrk gS fd ge tkok ds Source Codes dks Source File dh fdlh Line esa dgka ls fy[kuk “kq: djrs gSaA gkykafd ,slk djus ls gesa gh Program dks Debug djus esa ijs”kkuh gksrh gSA fuEu Statement dks nsf[k, % System.out.println(“Balgopal Nandlal”);

bl Statement dks ge Source File esa fuEukuqlkj Hkh fy[k ldrs gSa % System.out.println (“Balgopal Nandlal”);

blh rjg ls ;fn ge pkgsa] rks blh Statement dks fuEukuqlkj Hkh fy[k ldrs gSa& System. out. println ( “Balgopal Nandlal” );

Wrapper Classes

geus igys Hkh dgk gS fd tkok ,d Pure Object Oriented Programming Language gSA ;kuh blesa Primary Data Types dks Hkh Objects dh rjg Represent djds fofHkUu izdkj ds dke djus gksrs gSaA gkykafd ge Primary Data Type ds Variables Hkh Create dj ldrs gSa] ysfdu bUgsa fofHkUu izdkj dh Built–In Classes ds lkFk Use djus ds fy, gesa bUgsa Class Type esa Convert djuk iMrk gSA


Java in Hindi Conversion ds ckn ;s Class dks Represent djrs gSa] ysfdu buds eku esa dksbZ ifjorZu ugha vkrk gS cfYd budks Basic Data Type ls Class Type esa Convert dj fy;k tkrk gS] rkfd fofHkUu izdkj dh Built–In Classes bUgsa vklkuh ls mi;ksx esa ys ldsa vkSj ge bu ij fofHkUu izdkj dh mu Calculations dks Perform dj ldsa] tks dsoy Class ds Objects ds lkFk gh Perform dh tk ldrh gSaA

lkjka”k esa ge rks ;s dg ldrs gSa fd fofHkUu izdkj ds Basic Data Types dks mudh lEcaf/kr Wrapper Class }kjk Object esa Convert fd;k tkrk gSA rkfd ge Basic Data Types ds ekuksa dks Hkh mudh Class ds Objects ds :i esa mi;ksx esa ys ldsaA fofHkUu izdkj ds Basic Data Types ds ekuksa dks Object esa Convert djus ds fy, Number uke dh ,d Class java.lang uke ds Package esa miyC/k gSA ;s ,d Abstract Class gS ;kuh ge bl Class dk dksbZ Hkh Object Create ugha dj ldrs gSa] cfYd bldh Derived ;k Subclasses ds Objects Create djrs gSaA bl Class ls Derive dh xbZ dqy 6 Classes Byte, Short, Integer, Float, Long, Double gSa] tks Øe”k% byte, short, int, float, long, double Basic Data Types dks Represent djrh gSaA bls ge fuEukuqlkj ,d lkj.kh ds :i esa Represent dj ldrs gSa% Wrapper Class for Converting Simple Types Simple Data Type Boolean Char Double Float Int Long

Corresponding Wrapper Class Boolean Character Double Float Integer Long

tkok dh bu Wrapper Classes esa fofHkUu izdkj ds Basic Data Type o Objects dks Handle djus ds fy, dbZ Unique Methods dks Define fd;k x;k gSA buesa ls dqN t:jh o T;knk mi;ksx esa vkus okys Methods o mUgsa mi;ksx esa ysus dk Description vkxs crk;k tk jgk gSA fdlh Basic Data type ds Variable ;k Constant dks ;fn lEcaf/kr Wrapper Class ds Object esa Convert djuk gks] rc gesa mu lEcaf/kr Wrapper Classes ds Constructors dks Use djuk gksrk gSA ;s dke ge fuEukuqlkj Code Statement }kjk dj ldrs gSa% A. Converting Primary Numbers to Object Numbers Using Constructor Methods Constructor Calling Integer IntVal = new Integer( i ); Float FloatVal = new Float( f ); Double DoubleVal = new Double( d ); Long LongVal = new Long( l );

Performed Conversion Action Conversion from int Data Type to Integer Object Conversion from float Data Type to Float Object Conversion from double Data Type to Double Object Conversion from long Data Type to Long Object


Java in Hindi bl Table esa i, f, d o l Øe”k% int, float, double o long izdkj ds Basic Data Type ds Variables gSa] ftUgsa muds Corresponding Class ds Object esa Convert fd;k tk jgk gSA ,d ckj fdlh Basic Data Type ds eku dks lEcaf/kr Object esa Convert djus ds fy, fofHkUu izdkj ds Operations Perform djus ds ckn ;fn gesa ml Object dks fQj ls lEcaf/kr Basic Data Type esa Convert djuk gks] rks gesa Wrapper Classes ds fuEu typeValue() Methods dks Call djuk gksrk gS] tgka type ml Type dks Represent djrk gS] ftl Basic Data Type esa Object ds eku dks Convert djuk gSA B. Converting Object Numbers to Basic Numbers Using typeValue() Methods Method Calling int i = IntObj.intValue(); float f = FloatObj.floatValue(); double d = DoubleObj.doubleValue(); long l = LongObj.longValue();

Performed Conversion Action Conversion from Integer Object to int Data Type Conversion from Float Object to float Data Type Conversion from Double Object to double Data Type Conversion from Long Object to long Data Type

dbZ ckj ,slh t:jr gksrh gS fd gekjs ikl Primary Data Type ds Numerical eku gksrs gSa] ysfdu mUgsa ,d String dh rjg Use djuk gksrk gSA fdlh Numerical eku dks String dh rjg Use djus ds fy, gesa ml Numerical eku dks igys String izdkj ds Representation esa Convert djuk gksrk gSA fdlh Basic Data Type ds eku dks String Representation ds :i esa Convert djus ds fy, gesa Wrapper Class ds fuEu Methods dks Use djuk gksrk gS% C. Converting Basic Numbers to Strings Using String() Methods Method Calling str = Integer.toString( i ); str = Float.toString( f ); str = Double.toString( d ); str = Long.toString( l );

Performed Conversion Action Conversion from int Data Type to String Object Conversion from float Data Type to String Object Conversion from double Data Type to String Object Conversion from long Data Type to String Object

blh izdkj ls dbZ ckj gesa ,slh t:jr gksrh gS fd gesa fdlh eku dks nwljs eku ls Calculate djds u;k eku Generate djuk gksrk gS] ysfdu gekjs ikl tks Numerical eku gksrk gS] og String Format esa gksrk gS] ftl ij fdlh Hkh izdkj ds Numerical Operation dks Directly Perform ugha fd;k tk ldrk gSA bl fLFkfr esa igys gesa eku ds String Representation dks Wrapper Class Object Representation esa Convert djuk gksrk gS vkSj mlds ckn ml Object Representation dks Basic Data Type esa Convert djds eku ds lkFk Calculation Perform djuk gksrk gSA String Representation dks Wrapper Object esa Convert djus ds fy, gesa fuEu lkj.kh ds vuqlkj dke djuk gksrk gSA D. Converting String to Numerical Objects Using Static Method ValueOf() Method Calling DoubleObj = Double.valueOf( str ); FloatObj = Float.valueOf( str ); IntObj = Integer.valueOf( str ); LongObj = Long.valueOf( str );

Performed Conversion Action Conversion from String Object to double Data Type Conversion from String Object to float Data Type Conversion from String Object to int Data Type Conversion from String Object to long Data Type 142

Any Question or Suggestion, Just Discuss Here...

Java in Hindi fdlh String Representation dks Numerical Object esa Convert djus ds ckn ml Numerical Representation dks fQj ls Basic Data Type esa Convert fd;k tk ldrk gSA Numerical Strings ekuksa dks Parsing Methods dk iz;ksx djds Directly Primary ;k Basic Data Type ds ekuksa esa Convert fd;k tk ldrk gSA Parsing Methods dsoy nks gh gSa] tks fd fdlh Integer ;k Long izdkj ds String Representation dks Directly Integer ;k Long izdkj ds Basic Data Type dk eku Return dj nsrk gSA E. Converting Numerical Strings to Primary Numbers Using Parsing Method Method Calling int i = Integer.parseInt( str ); long i = Long.parseLong( str );

Performed Conversion Action Conversion from String Object to int Data Type Conversion from String Object to float Data Type

;fn parseInt() o parseLong() Methods esa Pass fd, tkus okys str String Object esa Integer eku ds vykok dksbZ eku gks] rks ;s Methods ,d NumberFormatException Throw djrs gSaA blfy, bUgsa try Block esa Use djuk pkfg, vkSj bl Exception dks Handle djus ds fy, ,d catch Block Hkh fy[kuk pkfg,] vU;Fkk str esa Integer ds vykok dksbZ nwljk eku gksus ij Program Crash ;k Terminate gks tkrk gSA Program // File Name: AdditionApplet.java import java.awt.*; import java.applet.*; public class AdditionApplet extends Applet { TextField textField1; TextField textField2; public void init() { textField1 = new TextField(5); textField2 = new TextField(5); add(textField1); add(textField2); textField1.setText("0"); textField2.setText("0"); } public void paint(Graphics g) { int value1 = 0, value2 = 0, sum = 0; String s ; g.drawString("Type a number in each box.", 10, 20);


Java in Hindi try {

s = textField1.getText(); value1 = Integer.parseInt(s); s = textField2.getText(); value2 = Integer.parseInt(s);

} catch(Exception excp) { g.drawString("Enter a Valid Number", 300, 20); } sum = value1 + value2; s = String.valueOf(sum);

}

}

g.drawString("The sum of the values is:", 10, 40); g.drawString(s, 160, 40);

public boolean action(Event event, Object arg) { repaint(); return true; }


Java in Hindi Description:

bl Applet Program esa lcls igys geus Applet Window esa nks TextField Objects textField1 o textField2 Create fd, gSaA fQj Applet ds init() Method esa bu nksuksa Text Boxes dks Applet Window esa add Method }kjk Add fd;k gS vkSj muesa Default eku 0 Display fd;k gS] rkfd Applet Window ij Text Boxes Empty fn[kkbZ uk nsaA fQj paint() Method esa Graphics Class dk ,d Object g Create fd;k gS] rkfd Applet ij fofHkUu izdkj ds Text Messages dks Display fd;k tk ldsA paint() Method esa rhu Integer izdkj ds Basic Data Type ds Variables Create fd, gSaA value1 uke ds Variable esa igys Text Box dk eku Store fd;k tkrk gSA value2 uke ds Variable esa nwljs Text Box dk eku Store fd;k tkrk gS vkSj sum uke ds Variable esa bu nksuksa ekuksa ds ;ksx dks Store fd;k tkrk gSA tkok esa ge tc Hkh dksbZ Basic Data Type dk Variable Create djrs gSa] gesa mu Variables dks Initialize djuk t:jh gksrk gSA ;fn ge ,slk ugha djrs gSa] rks tkok dk Compiler Error Generate djrk gS vkSj Program dks Compile ugha gksus nsrk gSA blhfy, value1, value2 o sum uke ds rhuksa Integer Variables dks eku 0 Initialize fd;k x;k gSA pwafd Text Box esa User tks Hkh eku Input djrk gS] og eku String Format esa gksrk gS vkSj gesa bl String izdkj ds eku dks nwljs Text Box esa fn, x, String izdkj ds eku ls tksMuk gS] blfy, lcls igys gesa bu String izdkj ds ekuksa dks Integer izdkj ds ekuksa esa Convert djuk t:jh gksrk gS] rkfd mu ij Arithmetical Operations dks Perform fd;k tk ldsA bl dke dks iwjk djus ds fy, geus String Class dk ,d Object s Create fd;k gS] rkfd Text Boxes ls Return gksus okys String Format ds eku dks Integer Format esa Convert djds value1 o value2 uke ds Variables esa Store fd;k tk ldsA User nksuksa Text Boxes esa ekuksa dks Fill djs] blds fy, Applet Window ij ,d Message “Type a number in each box.” dks Location Number (10, 20) ij Display fd;k x;k gSA blds ckn User tks Hkh eku Applet ij fn[kkbZ nsus okys nksuksa Text Boxes esa Fill djrk gS] mu ekuksa dks izkIr djus ds Statement dks try {} Block esa fy[kk x;k gSA

rkfd ;fn User bu Text Boxes esa Integer ds vykok dqN Hkh Fill djrk gS] rks Throw gksus okys Exception dks blds uhps fn, x, catch() Exception Block esa Catch djds Exception dks Process fd;k tk lds] rkfd Program Crash uk gksA User us igys Text Box esa tks Hkh eku Input fd;k gksrk gS] og eku s uke ds String izdkj ds Object esa Store gks tkrk gSA fQj bl eku dks Integer Wrapper Class ds parseInt() Method esa Pass djds Basic Integer Data Type ds eku esa Convert dj fy;k tkrk gS vkSj ml Integer izdkj ds Basic Data Type esa Converted eku dks value1 uke ds Basic Integer Data Type ds Variable esa Store dj fy;k tkrk gSA blh rjg ls nwljs Text Box okys eku dks Hkh value2 uke ds Basic Integer Data Type ds eku esa Convert djds Store

dj fy;k tkrk gSA

Text Box esa Fill fd, x, eku dks Integer izdkj ds eku esa Convert djus ds fy, fy[ks tkus okys Codes dks geus try{} Block esa blfy, fy[kk gS] D;ksafd User Text Boxes esa tks dqN Hkh


Java in Hindi Enter djrk gS] og s uke ds String izdkj ds Object esa Store gksrk gSA fQj tc bl String izdkj ds Object s esa Stored eku dks parseInt() Method }kjk Integer izdkj ds eku esa Convert fd;k tkrk gS] rc ;fn s esa iw.kkZad la[;kvksa ;kuh Integers ds vykok dqN Hkh gksrk gS] rks ;s Method ,d Exception Throw djrk gSA

;fn bl Exception dks Handle uk fd;k tk,] rks Program Crash gks ldrk gSA blfy, bl Exception dks Handle djus ds fy, try {} Block ds Just ckn esa catch() Block Define fd;k x;k gSA bl catch Block esa ,d Message Display djus ds fy, Statement fy[kk x;k gSA tks mlh fLFkfr esa Execute gksrk gS] tc try Block esa dksbZ Error ;k Exception Generate gksrk gSA tSls gh User Text Boxes esa Integer ds vykok dqN Hkh Fill djds Enter Key Press djrk gS] ,d action Event Generate gksrk gS vkSj repaint() Method paint() Method dks Call dj ysrk gSA paint() Method esa gh try...catch Block dks Define fd;k x;k gSA blfy, ;fn User us Text Boxes esa lgh eku ;kuh Integer Input fd;k gS] rc rks Applet ij nksuksa Text Boxes ds ekuksa dk ;ksx fn[kkbZ nsrk gS] vkSj ;fn User us fdlh Hkh Text Box esa Integer ds vykok dqN Hkh Input djds Enter Key dks Press fd;k gS] rks ,d Exception ds dkj.k Applet Window ij ,d Error Message “Enter a Valid Integer Number” fn[kkbZ nsus yxrk gSA bu nksuksa gh fLFkfr;ksa ds Applet dks fp= esa n”kkZ;k x;k gSA tc User lgh eku Input djrk gS] rc nksuksa Text Boxes ds eku value1 o value2 uke ds Variables esa Basic Integer Data Type ds :i esa Store gks tkrs gSaA bu ekuksa dks tksM dj buds ;ksx dks sum uke ds Variable esa Store dj fy;k tkrk gSA pwafd vc gesa sum esa Stored nksuksa Text Boxes ds ekuksa ds ;ksx dks Applet ij Display djuk gS] ysfdu sum ,d Integer izdkj dk Variable gS] ftlds eku dks Directly drawString() Method }kjk Display ugha djok;k tk ldrk gSA ;kuh ge fuEukuqlkj Statement }kjk sum dks Applet ij Draw ugha dj ldrs gSa% g.drawString("The sum of the values is:", 10, 40); g.drawString(sum, 160, 40);

ge ,slk blfy, ugha dj ldrs gSa] D;ksafd drawString() Method dsoy Strings dks gh Applet ij Draw dj ldrk gSA blfy, sum esa fLFkr Basic Integer Data Type ds eku dks igys String izdkj ds Object esa Convert djuk t:jh gSA bl Conversion dks Perform djus ds fy, geus fuEukuqlkj Statement dks Use fd;k gS% sum = value1 + value2; s = String.valueOf(sum);

bl Statement }kjk geus Basic Integer Data Type ds sum esa Stored eku dks String izdkj ds eku esa Convert djds s uke ds String izdkj ds Variable esa Store fd;k gS vkSj fQj fuEu Statement }kj sum ds eku dks Applet ij Display dj fn;k gS% g.drawString("The sum of the values is:", 10, 40); g.drawString(s, 160, 40);


Java in Hindi Integer ds ctk; ;fn gesa Float ;k double izdkj ds ekuksa dk ;ksx djuk gks] rks gesa gekjs Program esa dqN Basic ifjorZu djus gksaxsA D;ksafd ge fdlh Hkh Float izdkj ds eku dks tkok esa Directly ugha tksM ldrs gSa vkSj uk gh bUgsa tksMus ds fy, dksbZ Parsing Method gh tkok

esa miyC/k gSaA

bl fLFkfr esa lcls igys gesa Text Boxes ds String izdkj ds eku dks Float izdkj ds Wrapper Object esa Convert djuk gksxkA fQj ml Wrapper Object ds eku dks Basic Float izdkj ds eku esa Convert djuk gksxk vkSj nksuksa Text Boxes ds ekuksa dks bl izdkj ls Basic Float Data Type esa Convert djus ds ckn mUgsa tksMuk gksxkA bl izfØ;k dks ge vxys Applet Program }kjk le> ldrs gSa% Program import java.awt.*; import java.applet.*; public class FloatAdditionApplet extends Applet { TextField textField1; TextField textField2; public void init() { textField1 = new TextField(5); textField2 = new TextField(5); add(textField1); add(textField2); textField1.setText("0"); textField2.setText("0"); } public void paint(Graphics g) { float value1 = 0, value2 = 0, sum = 0; String s ; Float toBasicFloat; g.drawString("Type a number in each box.", 10, 20); try {

}

s = textField1.getText(); toBasicFloat = Float.valueOf(s); value1 = toBasicFloat.floatValue(); s = textField2.getText(); toBasicFloat = Float.valueOf(s); value2 = toBasicFloat.floatValue();


Java in Hindi catch(Exception excp) { g.drawString("Enter a Valid Integer Number", 300, 20); } sum = value1 + value2; s = String.valueOf(sum);

}

}

g.drawString("The sum of the values is:", 10, 40); g.drawString(s, 160, 40);

public boolean action(Event event, Object arg) { repaint(); return true; }

Description:

bl Program esa ge ns[k ldrs gSa fd geus Integer ds ctk; bl ckj Float izdkj ds rhu Variables Create fd, gSa vkSj Text Box ds eku dks Hold djus ds fy, String izdkj dk ,d Object s Create fd;k gSA pwafd gesa Wrapper Class Float ds ek/;e ls Text Box ds eku dks Basic Float izdkj ds eku esa Convert djuk gS] blfy, geus toBasicFloat uke dk ,d Wrapper Float Class dk Object Create fd;k gSA ;s Program fiNys Program dh rjg gh gSA geus dsoy blds try {} Block esa gh ifjorZu fd;k gSA


Java in Hindi User tks Hkh eku Text Box esa Fill djrk gS] og eku s uke ds String izdkj ds Object esa Store gks tkrk gSA fQj bl Object ds eku dks Float izdkj ds Wrapper Object esa Convert djus ds fy, Float.valueOf(s) Statement }kjk String Object s esa Stored eku dks Float izdkj ds Object esa Convert fd;k tkrk gSA

;s Converted eku Float izdkj ds Object toBasicFloat esa Store gksrk gSA blds ckn bl Float Object esa Stored eku dks Basic Float Data Type esa Convert djus ds fy, Float Object toBasicFloat ds Reference esa floatValue() Method dks Call fd;k tkrk gSA ;s Method ftl Object ds Reference esa Call gksrk gS] ml Object ds eku dks Basic Float Data Type ds eku esa Convert djds Return dj nsrk gS] ftls value1 uke ds Basic Float izdkj ds Variable esa Store dj fy;k tkrk gSA blh rjg ls nwljs Text Box ds eku dks Hkh Basic Float Object esa Convert djds value2 uke ds Basic Float izdkj ds Variable esa Store djds j[k fy;k tkrk gSA blds ckn ;s Program Hkh mlh rjg ls Flow gksrk gS] ftl rjg ls fiNyk Program Flow gksrk gSA ftl rjg ls geus fiNys nks Applet Programs }kjk tksM djus dh Process dk o.kZu fd;k gSA mlh rjg ls fofHkUu izdkj ds Arithmetical Operations dks Perform djus ds fy, Hkh gesa fofHkUu izdkj dh Wrapper Classes dk iz;ksx djds fofHkUu izdkj ds vko”;drkuqlkj Conversions djus gksrs gSaA mijksDr nksuksa Applet Programs dks ge cgqr gh vklkuh ls Application Programs esa Convert dj ldrs gSaA ;fn ge bl Applet dks T;ksa dk R;ksa GUI Application esa Convert djuk pkgsa] rks bls T;ksa dk R;ksa GUI Application esa Convert dj ldrs gSaA ysfdu bl Conversion dks ge vkxs le>saxsA GUI Mode esa User ls Input izkIr djus ds fy, gesa Applet Window ;k Application Window esa GUI Objects tSls fd Text Boxes, Radio Buttons, Command Buttons vkfn dks Create djuk iMrk gSA

ysfdu tc ge Consol Mode Application esa User ls Input izkIr djuk pkgrs gSa] rc gesa dqN vyx Classes dk iz;ksx djuk t:jh gksrk gSA ysfdu Console Mode Applications esa Hkh gesa fofHkUu izdkj dh Arithmetical Calculations dks Perform djus ds fy, Wrapper Classes dk iz;ksx djuk t:jh gksrk gSA Console Mode Application esa fiNys Applet dks Convert djus ds fy, gesa fuEukuqlkj Console Mode Program Develop djuk gksrk gS % Program // File Name: FloatAdditionApplication.java import java.io.*; public class FloatAdditionApplication { public static void main(String arg [])


Java in Hindi {

Float value1 = new Float(0); Float value2 = new Float(0); float sum = 0; String s; try {

DataInputStream in = new DataInputStream(System.in); System.out.println("Enter First Value : "); System.out.flush(); s = in.readLine(); value1 = Float.valueOf(s); System.out.println("\nEnter Second Value : "); System.out.flush(); s = in.readLine(); value2 = Float.valueOf(s);

}

}

} catch(Exception excp) { System.out.println("\nYou have not entered a Valid Number"); System.exit(1); } sum = value1.floatValue() + value2.floatValue(); System.out.println("\nThe sum of the values is: " + sum);

Output : When entered valid Value Enter First Value : 20.65 Enter Second Value : 689.5 The sum of the values is: 710.15

Output : When not entered valid Value Enter First Value : 12.55 Enter Second Value : f12.2


Java in Hindi You have not entered a Valid Number Description: Console Mode Application esa gesa fofHkUu izdkj ds dke djus ds fy, ftu Basic Classes dh t:jr gksrh gS] os Classes gesa java.io Package }kjk izkIr gksrh gSa] blfy, bl Package dks gesa gekjs Program esa Import djuk t:jh gksrk gSA

pwafd Application Program esa Compiler gesa”kk main() Method dks [kkstrk gS] blfy, bl Program esa geus gekjh Coding dks main() Method esa gh fy[kk gSA main() Method esa geus lcls igys Float Wrapper Class ds nks Objects value1 o value2 dks new Operator dk iz;ksx djds Create fd;k gS] lkFk gh Create gksus okys Object dks eku 0 ls Initialize Hkh fd;k gSA

eku 0 dks geus Float(0) Code }kjk Initialize fd;k gSA ;s Code tkok dk ,d Default Constructor gS] ftls ge Define ugha djrs gSaA tkok esa ;s Default Constructor igys ls gh Defined gSA Constructor ,d ,slk Method gksrk gS] tks ml Class ds Create gksus okys Object dks Initialize djus dk dke djrk gS vkSj fcuk Call fd, gq, Automatically Call gksrk gS] D;ksafd fdlh Hkh Class ds Constructor dk gesa”kk ogh uke gksrk gS] tks mldh Class dk uke gksrk

gSA

pwafd ge Float Wrapper Class dk Object Create dj jgs gSa] blfy, Float() uke dk Constructor Execute gks tkrk gS vkSj Create gksus okys Object dks Initialize dj nsrk gSA blh rjg ls geus sum uke dk ,d Basic Float izdkj dk Variable Hkh Create fd;k gS vkSj String dks Hold djus ds fy, String Class dk ,d Object s Hkh Create fd;k gSA tkok esa System Class fofHkUu izdkj ds Input o Output Devices dks Represent djrk gSA ;kuh tc gesa Monitor ij dqN Display djuk gksrk gS] rc Display fd, tkus okys Matter ;k eku dks System Class ds out Object esa Hkstuk gksrk gS vkSj tc gesa Keyboard ls dksbZ Matter ;k eku Input ds :i esa izkIr djuk gksrk gS] rc gesa System Class ds in Object dks Use djuk gksrk gSA Keyboard dks Represent djus okyh tkok dh Class dk uke DataInputStream gSA ;kuh ;fn gesa Keyboard ls dksbZ eku izkIr djuk gS] rks gesa DataInputStream Class dk ,d Object Create djuk iMrk gS vkSj ml Object esa Keyboard ls vkus okys ekuksa dks Store djuk gksrk gSA

blhfy, geus DataInputStream Class dk in uke dk ,d Object Create fd;k gS vkSj bl Object ds System.in uke dk eku Argument ds :i esa mlds Constructor dks iznku fd;k gS] ftldk eryc ;s gS fd ge bl Object esa Keyboard ls vkus okys ekuksa dks Store djsaxsA fQj vxys Statement esa geus Screen ij izFke eku Input djus ds fy, ,d Message “Enter First Value” iznku fd;k gS vkSj Input Buffer dks Clear djus ds fy, ;kuh ;fn Screen ;k Monitor ds Buffer esa dksbZ Character Stored gks] rks mls lkQ djus ds fy,


Java in Hindi System Class ds out Object ds Reference esa System Class ds flush() Method dks Call fd;k gS] rkfd Calculation esa Garbage Value Display uk gksA User Keyboard ls dksbZ Numerical eku Input djs ;k Character Input djs] og tks dqN Hkh Enter djrk gS] og lcdqN String gh gksrk gSA blfy, Keyboard ls vkus okyh String dks Read djus ds fy, in Object ds fy, readLine() Method Keyboard ls Input dh xbZ String dks Return djrk gSA

pwafd Keyboard ls String Read gks jgh gS] blfy, bl String dks Hold djus ds fy, Hkh ,d String Variable dh gh t:jr gksrh gSA vr% geus Keyboard ls Read gksus okyh String dks s uke ds String izdkj ds Object esa Store fd;k gSA fQj bl String dks Float Wrapper Class ds Object esa Convert djus ds fy, Float.valueOf(s); Code dks Use fd;k gSA ;s Conversion Method String esa Stored Numerical eku dks Float Object izdkj ds eku esa Convert djds value1 Object esa Store dj nsrk gSA blh rjg ls nwljs eku dks Hkh Keyboard ls Read djds mls Hkh Float izdkj ds Object value2 esa Store dj nsrk gSA pwafd User ls Input izkIr djus okys Statements dks geus try { } Block esa fy[kk gS] blfy, ;fn User Numerical eku ds ctk; dksbZ Character Input dj nsrk gS] rks try {} Block ,d Exception Throw djrk gSA bl Exception dks catch Block Catch dj ysrk gS vkSj Monitor ij ,d Error Message Display djds Program dks Terminate dj nsrk gSA pwafd value1 o value2 nksuksa gh Float izdkj ds Objects gSa] ftUgsa Basic Float izdkj ds eku esa Convert fd, fcuk tksMk ugha tk ldrk gS] blfy, floatValue() Conversion Methods dks Program ds vfUre Statement }kjk value1 o value2 Float izdkj ds Object ds Reference esa Call djds igys bUgsa Basic Float izdkj ds eku esa Convert fd;k gSA ,slk djus ij ;s Objects Basic Float izdkj ds eku Return djrs gSa] ftUgsa Addition Operator (+) }kjk tksM dj sum uke ds Basic Float izdkj ds Variable esa Store fd;k x;k gS vkSj vUr esa bl Resultant eku dks Output esa Display dj fn;k x;k gSA fiNys lHkh Programs dks ns[k dj ge le> ldrs gSa fd tkok Data Type ds lEca/k esa fdrus Strict rjhds ls dke djrk gSA ;fn ge fdlh Hkh Statement esa mfpr Type Conversion uk djsa] rks tkok gekjs Program dks Compile ugha gksus nsrk gSA blh dkj.k ls tkok dk Program T;knk lqjf{kr o Error Free gksrk gS] D;ksafd ftruh Hkh Errors Generate gksuh gksrh gSa] os lHkh Program ds Compile Time esa gh Generate gks tkrh gSaA blfy, Run Time esa Program iwjh rjg ls lqjf{kr jgrk gSA

Control Statements

vHkh rd geus ftrus Hkh Examples ns[ks gSa] mu lHkh esa ftl Øe esa fofHkUu Statements fy[ks x, gksrs gSa] mlh Øe esa Program dk Execution gksrk gSA ysfdu dbZ ckj fdlh Program esa ,slh fLFkfr;ka iSnk gks tkrh gS] fd Program ds fofHkUu Statements ,d fuf”pr Øe esa Execute gks dj gekjs Required dke dks iwjk ugha dj ikrs gSaA ml fLFkfr esa Program ds Control dks viuk Normal Flow NksM dj fdlh vU; LFkku ls Statements dk Execution djuk iMrk gS] rks dbZ ckj ,slh fLFkfr iSnk gks tkrh gS fd gesa 152 Any Question or Suggestion, Just Discuss Here...

Java in Hindi fdlh ,d gh Statement dks ckj&ckj Execute djuk iMrk gSA bl rjg dh t:jrksa dks iwjk djus ds fy, tkok esa ftu Statements dks Use fd;k tkrk gS] mUgsa Control Statements dgrs gSaA

Program Control ge tkurs gSa fd dksbZ Hkh izksxzke Statements dk ,d leqg gksrk gS] ftUgsa lkekU;r;k ftl Øe esa Source File esa fy[krs gSa] os mlh Øe esa Execute gksrs gSaA fdlh izksxzke esa fy[ks x, Statements dk Execution, ftl Øe esa gksrk gS] ml Øe dks Flow Of Control dgk tkrk gSA dHkh&dHkh gekjs lkeus bl rjg dh fLFkfr;ka gksrh gSa] ftuds dkj.k gesa Statements ds Øe dks Conditions ds vk/kkj ij cnyuk iMrk gS vkSj Condition ds lR; ugha gksus rd fdUgha Statement ds lewg dks ckj&ckj Execute djuk iMrk gSA tkok esa bl izdkj ds dqN Statement miyC/k gSa] ftuesa Condition ds lR; gksus ij ge ml Condition ls lEcaf/kr Statement dk Execution dj ldrs gSa rFkk ;fn Condition lR; ugha gksrh gS rks ge vU; Statement dk Execution djrs gSaA ;s fo”ks’k izdkj ds Statements Control Statements dgykrs gSaA

Types Of Control Statement tkok esa fofHkUu izdkj ds Conditional Statements dks ge eq[;r;k rhu Hkkxksa esa ckaV ldrs gSa% Sequential Statements ftu Statements dk Execution gksus ds ckn Øe ls vxyh iafDr esa fy[ks Statements dk Execution gksrk gS] os Statements Sequential Statement dgykrs gSaA vHkh rd geus tks Hkh Statements Use fd;s gSa] os lHkh Sequential Statements gSaA tSls Assignment Statements, Output Statements vkfnA Program ds bl izdkj ds Flow dks Control dk Normal Flow dgk tkrk gS] D;ksafd bl izdkj ds Execution esa Program Control dk Flow ,d Øe esa pyrk jgrk gS vkSj Program Control dks fdlh vU; Point ij tkus dh t:jr ugha iMrh gSA bl izdkj ds Statements gj main() Method esa gksrs gSa vkSj fdlh Hkh izksxzke esa ;s vo”; gh gksrs gSaA

Conditional Statements izksxzke esa dbZ txg ij fdlh Condition ds vk/kkj ij Control dks vius lkekU; izokg dks NksM dj fdlh fHkUu fcanq ij ls Statement dk Execution djuk iMrk gSA bl izdkj ds p;ukRed Execution ds fy;s iz;qDr Statements dks Conditional Statements ;k Branching Statements dgk tkrk gSA


Java in Hindi ;kuh tc fdlh leL;k ds fdlh “krZ ds vuqlkj nks ;k nks ls vf/kd ifj.kke laHkkfor gksrs gSa] rc fdlh fuf”pr ifj.kke ij igqapus ds fy;s izksxzke dks viuk Normal Flow NksM dj fdlh fHkUu fcanq ls Program dks Execute djuk iMrk gSA bl izfØ;k dks izksxzke dh Branching gksuk dgrs gSA goto Statement fcuk Condition dk ,d ,slk Control Statement gS] ftls ge looping o Branching nksuksa :iksa esa iz;ksx dj ldrs gaSA bl izdkj ds Control Statements eq[;r% pkj izdkj ds gksrs gSa&

Iterative Statements tc izksxzke esa dqN Statements dks fdlh Condition ij fuHkZj djrs gq, tc ckj&ckj nksgjkus dh vko”;drk gksrh gS] rks iqujkorhZ ;k Iterative Statements dk iz;ksx fd;k tkrk gSA tkok esa Iterative Statements eq[;r% rhu gksrs gSa&

Compound Statement or Block tc Statement ds ,d lewg dks bdkbZ ds :i esa ysrs gSa] rks mls Block ;k Compound Statement dgrs gSaA ,d Block esa ys dks’Bd esa fy[ks tkrs gSaA ,d Block esa dks’Bd ds vUnj dbZ Definitions, Declarations o Statements dk lewg gks ldrk gSA tSls% {

//Starting of the Block int a; float b; double c;


Java in Hindi c = a+b; ………… ………… }

//End of the Block

if statement lHkh Control Statements esa ls if Statement lcls “kfDr”kkyh Statement gS] ftlds }kjk ge Statements ds Execution ds Flow dks Control dj ldrs gSaA ;g ,d f} ekxhZ ( Two Way ) Statement gS] ftlesa Condition ds lR; ;k vlR; gksus ds vk/kkj ij fuHkZj djrs gq, izksxzke dk Control nks vyx&vyx fcanqvksa ij igqap ldrk gSA bl rjg If Statement ds vuqlkj izksxzke ds ikl nks jkLrs gksrs gSa] ,d Condition ds lR; gksus dh fLFkfr esa o nwljk Condition ds vlR; gksus dh fLFkfr esaA tc gesa Condition ds lR; gksus ij dsoy ,d Statement dk Execution djuk gksrk gS] rc ge fuEu izdkj ds Syntax esa if Condition dks Use dj ldrs gSa& if ( Expression and Condition ) Statement 1;

blesa tc if Condition lR; gksxh rc Statement 1 Execute gks tk,xkA tc gesa fdlh Condition ds lR; gksus ij ,d ls vf/kd Statements dk Execution djuk gks] rks gesa lHkh Statements ea>ys dks’Bd esa fy[kus iMrs gSaA ;fn ge ,slk ugha djrs o Åij crk, Syntax ds vuqlkj gh izksxzke fy[k nsrs gSa] rks Condition ds lR; gksus ij Java Compiler igys Statement dk rks Execution dj nsrk gS] ysfdu “ks’k Statements dks Program dh Condition ds vuqlkj Execute ugha djrk cfYd mUgsa Program ds Normal Flow ds vuqlkj Execute djrk gSA bl fLFkfr esa igys Statement dks NksMdj ckdh ds lHkh Statements gesa”kk Execute gksrs gSas pkgs if Condition lR; gks pkgs vlR;A blfy;s ;fn if Condition ds izksxzke esa ,d ls vf/kd Statements dk Execution djuk gks rks gesa fuEu if Syntax Use djuk iMrk gS& if ( Expression and Condition ) { Statement 1; Statement 2; “ “ “ “ “ “ Statement n; } Other Statements

blesa tc Condition lR; gksrh gS] rks Block ds vUnj fy[ks lkjs Statements dk Execution gks tkrk gS] mlds ckn Other Statements dk ;kuh Block ls ckgj ds Statements dk Execution gksrk gSA ysfdu ;fn Condition vlR; gksrh gS] rks izksxzke Control, if Condition ds Block dks NksM dj lh/ks gh Other Statements ;kuh Block ds ckgj ds Statements dk Execution dj nsrk gSA 155 Any Question or Suggestion, Just Discuss Here...

Java in Hindi Condition lR; gks ;k vlR; fQj Hkh Other Statements ;kuh Block ls ckgj ds Statement dk Execution gksrk gS] D;ksafd ;s Statement Sequential Flow esa gSA bl Control Statement ds vk/kkj ij ge fuEukuqlkj ,d Example Program Develop dj

ldrs gSaA

Example

,d ,slk Program cukvks ftlesa nks la[;kvksa esa ls cMh la[;k dks Output esa Print fd;k tk,A Program public class IfControlStatement { public static void main(String args[]) { float firstNumber = 5787.54f; float secondNumber = 8454.12F; float result; if(firstNumber > secondNumber){ System.out.println("firstNumber is Greater than secondNumber "); System.out.println("and secondNumber is Less than firstNumber"); }

}

}

if(secondNumber > firstNumber) { System.out.println("secondNumber is Greater than firstNumber "); System.out.println("and firstNumber is Less than secondNumber "); }

Output secondNumber is Greater than firstNumber and firstNumber is Less than secondNumber

bl Program esa geus float izdkj ds nks ekuksa dh rqyuk dh gSA Program Control tc igys if Statement ij igqaprk gS] rc og firstNumber esa Stored eku dh rqyuk secondNumber esa Stored eku ls djrk gSA pwafd firstNumber esa Stored eku Variable secondNumber esa Stored eku ls NksVk gS] blfy, izFke if Statement false Return djrk gSA tc dksbZ Control Statement false Return djrk gS] rc Program Control ml Control Statement ds Statement Block esa izos”k ugha djrk gSA blfy, gekjs Program esa Program Control izFke if Statement ds Statement Block dks Skip dj nsrk gSA fQj Program Control dks nwljk if Statement feyrk gSA blesa secondNumber Variable dk eku firstNumber Variable ds eku ls NksVk gksus dh otg ls Boolean eku true Return gksrk gSA true Return gksus ij Program Control nwljs if Control Statement ds Statement Block esa izos”k djrk gS vkSj ml Block ds lHkh


Java in Hindi Statements dk Execution djrk gSA ifj.kkeLo:i gesa Output esa nwljs if Statement Block esa fy[ks x, Message izkIr gks tkrs gSaA

if – else statement tc gesa nks ;k nks ls vf/kd “krksaZ ds vk/kkj ij dksbZ fu.kZ; ysuk gksrk gS] ;k izksxzke ls dksbZ [kkl dke djokuk gksrk gS] rc ge if - else Statement dk iz;ksx djrs gSaA ;g lk/kkj.kr% if Statement dk foLr`r :i gSA bldk Syntax uhps fn[kk;k x;k gS& if ( Expression and Condition ) { Statement 1; Statement 2; “ “ “ Statement n; } else { Statement 3; Statement 4; “ “ “ Statement m; } Sequential Statement a;

bl Syntax ds vuqlkj tc if Condition lR; gksxh] rks Statement 1, Statement 2, ls Statement n rd dk Execution gksxk vkSj ;fn if Condition vlR; gksxh] rks izksxzke Control, if Statement Block dks NksM nsxk vkSj Default :i ls else Condition dh Statements dk Execution gks tk,xkA bl rjg ls Statement 3, Statement 4 ls Statement m rd dk Execution gksxkA ;fn if Condition lR; gksrh gS] rks else Block ds Statements dk Execution ugha gksrk gSA Input fd;s x, eku ds vk/kkj ij if ;k else Condition dk Execution gksus ds ckn izksxzke Control Sequential Statements dk Execution djrk gSA Sequential Statements dk rks Execution gksrk gh gS] D;ksafd ;s main() Method Block esa fy[ks x, gSa] vkSj Sequential Øe esa gSaA ;fn ge bl Statement dk iz;ksx fiNys Program esa djuk pkgsa] rks fuEukuqlkj dj ldrs gSa& Program public class IfElseControlStatement { public static void main(String args[]) { float firstNumber = 5787.54f; float secondNumber = 8454.12F; float result;


Java in Hindi

}

}

if(firstNumber > secondNumber) { System.out.println("firstNumber is Greater than secondNumber "); System.out.println("and secondNumber is Less than firstNumber"); } else { System.out.println("secondNumber is Greater than firstNumber "); System.out.println("and firstNumber is Less than secondNumber "); }

Output secondNumber is Greater than firstNumber and firstNumber is Less than secondNumber

ge ns[k ldrs gSa fd nksuksa gh Programs dk Output leku gh izkIr gksrk gSA ,slk blfy, gks jgk gS D;ksafd ;s Statement if Statement dk gh foLr`r :i gSA

Nested if else statement tc ,d if Condition ds Statement Block esa ,d vkSj if Condition ;k if else Condition ds Statement Block dk iz;ksx fd;k tkrk gS] rks bls if Condition dh Nesting djuk dgrs gSaA ge fofHkUu if Conditions dh vko”;drk ds vuqlkj Nesting dj ldrs gSa] ;kuh ge ,d if Condition ds Statement Block esa nwljk if ;k if else Condition dk Statement Block, nwljs esa rhljk if ;k if else Condition dk Statement Block, rhljs esa pkSFkk vkfn fdruh Hkh la[;k esa if Condition Statements Blocks dh Nesting dj ldrs gSaA bldk Syntax fuEukuqlkj gksrk gS& if ( Expression and Condition 1 ) { if ( Expression and Condition 2 ) { Statement 1; Statement 2; “ “ “ Statement l; } else { Statement 3; Statement 4; “ “ “ Statement m; }


Java in Hindi Inner Sequential Statement n; } else { Statement 5; Statement 6; “ “ “ Statement o; } Outer Sequential Statement a;

bl Syntax esa ;g crk;k x;k gS] fd ;fn izFke if Condition lR; gksrh gS] rks izksxzke Control izFke if Condition ds Statement Block esa tk,xkA ogka izksxzke Control dks nwljh if Condition feysxhA ;fn ;s nwljh if Condition Hkh lR; gS] rks izksxzke Control, Inner if Condition Statement Block esa tk,xk vkSj Statement 1, Statement2 ls Statement n rd ds Statements dk Execution djsxkA fQj Inner if Statement Block ds ckgj vkdj Outer if Condition Block ds Inner Sequential Statement n dk Execution djsxk vkSj var esa izksxzke Control nksuksa if Condition Statement Block ls ckgj vk dj Outer Sequential Statement a dk Execution djsxkA ysfdu ;fn Inner if Condition lR; uk gks] rks izksxzke Control, Inner else Statement Block ds Statement 3 ls ysdj Statement m rd ds Statements dk Execution djsxk vkSj Inner else ls ckgj vkdj Outer if Condition ds Inner Statement, Statement n dk Execution djsxkA vxj nksuksa gh if Conditions vlR; gks tkrh gS] rks izksxzke Control lh/ks gh Outer else Condition ds Statement Block dk Execution dj nsrk gS vkSj else Statement Block ls ckgj vkdj Outer Sequential Statement a dk Execution djrk gSA lkjka”k ds :i esa ge ;g dg ldrs gSa fd tc If Condition ds Statement Block dk Execution gksrk gS] rc else ds Statement Block dk Execution ugha gksrk] vkSj else Statement Block dk Execution rHkh gksrk gS] tc if Condition vlR; gks tkrh gSA bls vPNh rjg ls le>us ds fy;s ge fuEu mnkgj.k ns[krs gSa] ftlesa rhu la[;kvksa esa ls cMh la[;k dks Output esa Print fd;k tk jgk gS& Program public class NestedIfElseControlStatement { public static void main(String args[]){ float firstNumber = 5784547.54f; float secondNumber = 855454.12F; float thirdNumber = 45478.6545f; float result; if(firstNumber > secondNumber){ if(firstNumber > thirdNumber)


Java in Hindi else

}

}

result = firstNumber;

result = thirdNumber; } else { if(secondNumber > thirdNumber) result = secondNumber; else result = thirdNumber; } System.out.println("Largest Number is " + result);

Output Largest Number is 5784547.5

if – elseif – else Ladder statement tc gekjs ikl ,slh leL;k gksrh gS fd
bls Practically le>us ds fy, ge fuEukuqlkj Program cuk ldrs gSa ftlesa fdlh Student ds dqy Marks dh Total ds Percent ds vk/kkj ij Output esa Student dh Grade dk irk pyrk gSA Program public class IfElseIFLadderControlStatement { public static void main(String args[]) {


Java in Hindi float percent = 80;

}

}

if(percent > 79) System.out.println("Pass with Honors"); else if(percent > 59) System.out.println("First Division Pass "); else if(percent > 44) System.out.println("Second Division Pass "); else if(percent > 33) System.out.println("Third Division Pass"); else System.out.println("Fail");

Output Pass with Honors

bl Program esa ge ns[k ldrs gSa fd Student ds percent dk eku 80 gS] blfy, bl Control Statement dh igyh Condition gh true gks tkrh gS vkSj Output esa “Pass with Honors” Print gks tkrk gSA ysfdu ;fn percent dk eku 40 gksrk] rks pkSFkh else if Condition true gksrh vkSj Output esa “Second Division Pass Print” gksrkA switch statement tc ge fdlh izskxzke esa uk o i

Java in Hindi

dk;Ziz.kkyh & bl lajpuk esa value1, value2........value n expression ;k Variable gSa] ftUgs case label dgk tkrk gSA buds ckn Colon yxkuk t:jh gksrk gSA ;s lHkh eku vyx&vyx gksus t:jh gksrs gSaA Statement or Statement Block 1, Statement or Statement Block 2, ......... Statement or Statement Block n Statements dk lewg gSA bu Statements ds lewgksa esa ,d ls vf/kd Statements gksus ij Hkh ea>ys dks’Bd dh t:jr ugha gksrh gSA fQj Hkh ;fn ;s dks’Bd yxk fn;s tk,a] rks Hkh Java Compiler dksbZ ijs”kkuh ugha djrk gSA switch Statement ds Execution ds fy;s loZizFke variable ;k expression ds eku dh rqyuk Øe ls ,d&,d djds value1, value2 ...... value n ls dh tkrh gS vkSj tgka Hkh ;s eku fey tkrk gS] ml case label ds vuqlkj fy[ks x;s Statements dk Execution gks tkrk gSA

bl lajpuk esa lHkh Statements Block ds ckn break fy[kk tkrk gSA ;g Statements ds lewg dk var n”kkZrk gS o Statements Block ds Execution ds ckn izksxzke Control dks switch Statement ds ckgj sequential Statement a ij ys tkrk gSA ;fn ;g break uk fy[kk tk,] rks Statement Block ds Execution ds ckn Hkh Program Control switch Statement Block ds vanj gh jgrk gS vkSj vkxs ds Statement dk Execution djrk jgrk gS vkSj rc rd djrk jgrk gS tc rd fd bls dksbZ break Statement

ugha fey tkrkA


Java in Hindi switch Statement ds fy;s nh xbZ lajpuk esa default case label ,d Optional Label gSA ;fn ;g switch Statement esa gksrk gS o expression ;k variable dk eku switch Statement esa fn;s x, fdlh Hkh Statement ls esy ugh djrk] rks Program Control default case label ij pyk tkrk gS vkSj blds varxZr fn;s x, Statement dk Execution dj nsrk gSA switch case labels dks ge fdlh Hkh Øe esa j[k ldrs gSa] ;kuh pkSFks LFkku dk case izFke LFkku ij] izFke LFkku dk case rhljs LFkku ijA default Statement dks Hkh fdlh Hkh LFkku ij j[k ldrs gSaA bl Control Statement dks ge if else if Ladder Statement ds LFkku ij Use dj ldrs gSaA

;kuh ge fiNys Program dks fuEukuqlkj bl Statement ds iz;ksx }kjk Hkh fy[k ldrs gSa& Program public class SwitchControlStatement { public static void main(String args[]) { int percent = 75; percent = percent/10; switch(percent) { case 10: case 9: case 8: System.out.println("Pass with Honors"); break; case 7: case 6: System.out.println("First Division Pass "); break; case 5: System.out.println("Second Division Pass "); break;

}

}

}

case 4: System.out.println("Third Division Pass"); break; default: System.out.println("Fail");

Output First Division Pass 163 Any Question or Suggestion, Just Discuss Here...

Java in Hindi dHkh&dHkh gesa switch Statement esa fdlh Calculation ds fy, Variable Declare djus iMrs gSaA tc gesa fdlh switch Statement esa Variable Declare djuk iMrk gS] rc gesa Curly Braces ds Block dks Use djuk t:jh gksrk gSA ftl rjg ls ge if Control Statement dh Nesting dj ldrs gSa] mlh rjg ls ge switch Control Statement dh Hkh Nesting dj ldrs gSaA Increment and Decrement Increment tc fdlh Variable ds eku esa Øe ls dksbZ la[;k tksM dj okil mlh Variable esa Store dj nsrs gSa] rks ml Variable dk eku ml tksMh xbZ la[;k ds vuqlkj mlh Øe esa c
blls izFke ckj x dk eku 0 + 1 = 1 gks tk,xk D;ksafd x dk izkjafHkd eku geus 0 fn;k gSA tc nqckjk ;gh Statement execute gksxk rc x ds eku 1 esa 1 vkSj tqMsxk ;kuh x = 1 + 1 blfy;s vc x dk eku nks gks tk,xk D;ksafd igys Execution esa x dk eku c< dj ,d gks x;k FkkA vc ;fn rhljh ckj ;gh Statement Execute gks rks x = 2 + 1 gksus ls x dk eku 3 gks tk,xk vkSj ;g eku Øe ls rc rd c
Decrement blds foijhr tc fdlh Variable ds eku esa ls Øe ls dksbZ la[;k ?kVk dj izkIr eku okil mlh Variable esa Store dj nsrs gSa] rks ml Variable dk eku ml ?kVkbZ xbZ la[;k ds vuqlkj Øe ls ?kVrk tkrk gS] bl izfØ;k dks Variable dk Decrement gksuk dgrs gSaA mijksDr mnkgj.k dks gh ge Decrement ds fy;s Hkh Use dj jgs gSaA ekuk x = 10 gS o ge Øe ls x dk eku 1 de djuk pkgrs gSa] rks gesa fuEu Statement dks rc rd Use djuk gksxk tc rd fd Condition lR; jgrh gSA x=x–1

;gka x dk izkjafHkd eku geus 10 fn;k gSA tc igyh ckj ;s Statement Execute gksxk] rc x = 10 - 1 ;kuh x = 9 gks tk,xkA nwljh ckj esa x = 9 - 1 ;kuh x = 8 gks tk,xkA rhljh ckj esa x = 8 - 1 ;kuh x = 7 gks tk,xk vkSj ;g Øe Hkh rc rd pyrk jgsxk tc rd fd fdlh Condition }kjk bl izfØ;k dks jksd uk fn;k tk,A bls Variable dk Decrement gksuk dgrs gSa vkSj “C” Hkk’kk esa bls ,d vU; izdkj X-- ls Hkh fy[k ldrs gSaA 164 Any Question or Suggestion, Just Discuss Here...

Java in Hindi Increment o Decrement Hkh nks izdkj ds gksrs gSaA Pre - Increment o Post - Increment rFkk Pre - Decrement o Post Decrement. tc fdlh Variable ds igys Increment ++ dk fpUg yxk;k tkrk gS] rc ml Variable dk eku igys Increase gksrk gS] mlds ckn og Statement ;k Expression Execute gksrk gS] ftlesa ml Variable dks Use fd;k x;k gSSA

tSls ekuk

a = 10 , b = 15 c = a + ++b c = 10 + (1 +15) c = 10 + 16 c = 26

gS djus ij igys b esa ,d tqMsxk ftlls b dk eku 16 gks tk,xk b dk eku 16 gksus ds ckn b esa a dk eku 10 tqMsxk bl rjg ls c dk eku 25 uk gks dj 26 izkIr gksxk D;ksafd b dk Pre Increment gqvk gSA bl izdkj vc a = 10 o b = 16 gksxkA

tc fdlh Variable ds ckn esa Increment fpUg yxk;k tkrk gS] rks ml Variable dk eku mlh Statement ;k expression esa Increase ugha gksrk] cfYd igys og Statement ;k Expression Execute gksrk gS] mlds ckn ml Variable dk eku Increase gksrk gSA tSls ekuk a = 10 , b = 15 c = a + b++ c = (10 + 15 ) + 1 c = 25

gS djus ij igys a esa b tqMsxk a esa b tqMus ds ckn b dk eku Increase gks dj 16 gks tk,xk vkSj c dk eku 25 gh izkIr gksxk

;gh izfØ;k Variable ds Pre-Decrement o Post-Decrement esa Hkh gksrh gSA tSls fuEu mnkgj.k Pre-Decrement dk gS& a = 10 , b = 15 c = a + --b c = 10 + (-1 +15) c = 10 + 14 c = 24 Because b have been Pre Decremented Now The Values of Variables are a = 10 but b = 14 because b is Decremented

;g mnkgj.k Post Decrement dk gSA a = 10 , b = 15 c = a + b-c = (10 + 15) - 1 c = 10 + 15 c = 25 Because b have been Post Decremented Now The Values of Variables are a = 10 but b = 14 because b is Decremented

bl izdkj tc fdlh Variable ds ckn esa Increment ;k Decrement dk fpUg yxk;k tkrk gS] rks ml Variable dk eku izfØ;k ds ckn esa c
Java in Hindi Decrement dk fpUg yxk;k tkrk gS] rks ml Variable dk eku izfØ;k ls igys c
tSls c = a + b++ blesa Compiler dks ++ fpUg ls igys Variable b izkIr gksrk gS vkSj c dk eku 25 gh izkIr gksrk gSA tcfd ;fn Compiler dks igys] Variable ds lkFk Use fd;k x;k $$ ;k -- fpUg feyrk gS] rks Compiler igys ml Variable ds eku dk Increment ;k Decrement djrk gS] mlds ckn ml Variable dks expression esa Use djrk gSA tSls c = a + ++b blesa Compiler dks Variable b ds igys Increment Operator ++ izkIr gksrk gSA blfy;s a ds eku 10 esa b dk eku 15 tqMus ls igys c dk eku Incremented gks dj 16 gks tkrk gS vkSj fQj a + b dk eku c dks ;kuh 10 + 16 = 26 c dks fey tkrk gSA ++ Increment Operator gS vkSj -- Decrement Operator vkSj budk iz;ksx vf/kdrj Looping ds vUrxZr gh fd;k tkrk gS D;ksafd Loop dks gesa”kk ,d Øe esa gh c
,slh t:jrksa dks iwjk djus ds fy;s ge Looping Condition ds vUnj ;k vko”;drk ds vuqlkj dgha vkSj]] fdlh vU; Variable ds eku dks ,d ds Øe esa ?kVkus ;k c
Loops

;s rhljs izdkj ds Control Statements gksrs gSaA tc izksxzke esa gesa fdlh izfØ;k dks ckj&ckj nksgjkuk gksrk gS] rc ge Looping Control Statements dk iz;ksx djrs gSaA fdlh Hkh Loop esa gesa”kk rhu ckrsa fuf”pr djuh gksrh gSa& 1. bls Loop dk Initial Part dgk tkrk gSA blesa Loop dks Iterate djus okys Variable dks izkjafHkd eku fn;k tkrk gS] tks ;s r; djrk gS fd Loop dh “kq:vkr dc ls gksxhA ;gka gesa”kk Assignment Operator = dk iz;ksx fd;k tkrk gSA 2. bls Test Condition dgk tkrk gSA fdlh Hkh Loop esa ;g Part ;s r; djrk gS fd Loop fdl Condition esa execute gksxkA tc rd Test Condition lR; gksrh gS] rHkh rd Loop dk Iteration pyrk gSA blfy;s Loop ds bl Hkkx dks Define djuk cgqr gh t:jh gksrk gSA ;gh Hkkx fdlh Loop dks crkrk gS fd Loop dks dgka rd pyuk gSA bl Hkkx esa Conditional o Logical Operators dk iz;ksx fd;k tkrk gSA ;gka ,d Valid Condition nsuk cgqr gh t:jh gksrk gS] D;ksasfd ;fn ;gka ij ,d Valid Condition define ugha djrs gSa rks dbZ ckj Loop Infinite gks tkrk gSA 3. Loop ds bl esa Step Size crkuk gksrk gSA ;kuh ;gka Loop dks ;s crkuk gksrk gS fd Loop fdl Øe esa vkxs c

Java in Hindi Decrement Operator dk iz;ksx fd;k tkrk gSA ;fn gesa Loop dks ,d ds Øe esa uk c
vUrxZr crk;k x;k gSA

Loop eq[;r% rhu izdkj ds gksrs gSaA budh viuh&viuh] vyx&vyx fo”ks’krk o mi;ksx gSA bUgsa fuEukuqlkj crk;k x;k gS&

for Loop ;g lokZf/kd iz;ksx gksus okyk Loop gSA bl Loop esa “C” ds for Key Word dk iz;ksx gksrk gSA bl Loop esa Åij crk, x, rhuksa gh Hkkx ,d gh dks’Bd esa fy[kus gksrs gSaA bl Loop dh fo”ks’krk ;g gS] fd blds ftrus Hkh Statement gksrs gSa] mUgs for Loop fy[kus ds ckn mlds uhps ea>ys dks’Bd ds ,d Block eas fy[kk tkrk gS vkSj ;s Statements Block rHkh Execute gksrk gS] tc for Condition lR; gksrh gSA for Loop dk Syntax fuEukuqlkj gksrk gS& for( Initial Part; Conditional Part; Step Size Part) { Statements Block; }

Flow of For Loop

tc for Loop dk Execution gksrk gS] rks loZ izFke Loop dk Variable Initialize gksrk gS vkSj fQj Condition Check gksrh gSA ;fn Condition lR; gksrh gS] rks Program Control for Loop ds Statement Block esa tkrk gS vkSj ogka ds Statements dk Execution djrk gSA tc For Loop Statement Block ds lHkh Statements dk Execution dj nsrk gS rks Block ls ckgj vkus ls igys Loop ds Step Size Part dk Execution djrk gS vkSj crkbZ xbZ Size ds vuqlkj Variable dk eku Increment ;k Decrement djrk gSA fQj okil Condition Check djrk gS ;fn Condition lR; gksrh gS rks okil Statement Block esa tkrk gS vkSj lHkh Statements dk Execution djus ds ckn okil Step Size Part dk Execution djrk gSA ;s Øe rc rd pyrk jgrk gS tc rd fd for Loop dh Condition lR; jgrh gSA Loop dk Initialization dsoy ,d ckj gh gksrk gS tc igyh ckj Program Control For Loop esa izos”k djrk gSA for Loop dk Execution gesa”kk blh Øe esa gksrk gSA Example : bl Loop }kjk ge ,d izksxzke cukrs gSa ftlesa 1 ls 7 rd dh fxurh dks Output esa fuEukuqlkj Print djokuk gSaA 1 2 3 4


Java in Hindi 5 6 7

bl izksxzke dks ge igys xf.krh; :i esa fy[krs gSaA ge int izdkj dk ,d Variable i ysrs gSaA bl izksxzke esa fxurh dk izkjafHkd eku 1 gS vr% i dk izkjafHkd eku i = 1 dj ldrs gSaA ;g bl izksxzke ds Initial Part dk Declaration gSA Print gksus okyh fxurh dk vf/kdre eku 7 gS] blfy;s Condition ds :i esa ge ;s dg ldrs gSa fd Loop rc rd pyuk pkfg;s tc rd fd i dk eku 7 ugha gks tkrkA blfy;s ge bls xf.krh; :i esa i <= 7 fy[k ldrs gSaA ;g Expression izksxzke dks crkrk gS fd Condition rc rd lR; jgsxh tc rd fd i dk eku 7 ls de ;k 7 ds cjkcj ugha gks tkrkA ;g bl izksxzke ds Conditional Part dk Declaration gSA

bl izksxzke esa gj igyh la[;k gj nwljh la[;k ls cMh gSA blfy;s Loop ds Step Size Part esa gesa Increment Operator dk iz;ksx djuk gksxk vkSj lkFk gh gj la[;k ,d ds Øe esa c< jgh gS blfy;s gesa Variable ds eku dks gj Iteration esa ,d ds Øe esa c
bu rhuksa dks for Loop esa j[k nsrs gSa rks fuEu izdkj ls for Loop dk dks’Bd cu tkrk gSA /;ku nsa fd ;s rhuksa Expression vyx&vyx gSaA blfy;s bUgs ; ( Semicolon ) ls vyx djds fy[kk x;k gS& for(i = 1; i <= 7; i = i + 1)

or

for(i = 1; i <= 7; i++)

vc for Loop dk Statement Block fy[kuk gSA i dk eku Øe ls ,d&,d c< jgk gSA blfy;s Statement Block esa ;fn i dk eku Print dj fn;k tk,] rks gesa gekjk Output izkIr gks tk,xkA bls ge fuEukuqlkj fy[k ldrs gSa& { }

printf(“%d ”, i );

vc ;fn ge bu lHkh Statement dks ,d main() Method esa fuEukuqlkj fy[k dj Program dks Compile djsa] rks gesa gekjk Required ifj.kke izkIr gks tk,xkA Example Program fuEukuqlkj gS& Program public class ForLoop { public static void main(String args[]) { int i;


Java in Hindi

}

}

for(i=1; i<=7; i++) { System.out.println(i); }

bl Program esa geus for Loop esa <= Relational Operator dk iz;ksx fd;k gSA lcls igys ,d Integer izdkj ds Variable dk eku 1 gksrk gSA pwafd i dk eku 7 ls de gS] blfy, for Loop true Return djrk gSA true Return gksus dh fLFkfr esa Program Control Loop ds Block esa izos”k djrk gS vkSj i ds eku dks Print djrk gSA fQj Program Control i ds eku dk Increment djds 2 dj nsrk gSA Program Control fQj ls for Loop ds Parenthesis esa ;s Check djus ds fy, tkrk gS fd i dk eku Increment gksus ds ckn Hkh 7 ls de ;k cjkcj gS ;k ughaA pwafd i dk eku vHkh Hkh 7 ls de gS] blfy, Program Control fQj ls for Loop ds Block esa vkrk gS vkSj i ds eku dks fQj ls Print djrk gS] tks fd bl ckj 2 gksrk gSA Program Program eku 7 ls Control i

Control fQj ls i ds eku dks Increment djrk gSA vc i dk eku 3 gks tkrk gSA Control fQj ls for Loop ds Parenthesis esa tkrk gS vkSj Check djrk gS fd i dk de ;k cjkcj gS ;k ughaA ,d ckj fQj Condition true gksrh gS vkSj Program ds eku dks Print dj nsrk gSA

bl rjg ls i dk eku 7 ckj Increment gksrk gSA tc i dk eku Increment gksdj 8 gks tkrk gS vkSj Compiler fQj ls for Loop ds Parenthesis esa ;s Check djus ds fy, tkrk gS fd i dk eku 7 ls de ;k cjkcj gS ;k ughaA rc false Return gksrk gSA D;ksafd bl ckj i dk eku 8 gS tks fd 7 ls cMk gSA bl fLFkfr esa Program Control for Loop ds Statement Block esa izos”k ugha djrk vkSj lh/ks gh ckgj fudy tkrk gSA ge pkgsa rks tks Variable geus for Loop ds igys Declare fd;k gS mls for Loop ds Parenthesis esa Hkh Declare dj ldrs gSaA tks Variable dsoy Loop dks pykus ds fy, Declare fd;k tkrk gS] og Variable dsoy rHkh rd mi;ksxh gksrk gS tc rd Loop Run gksrk gSA blfy, ;fn ge pkgsa rks for Loop ds Statement dks fuEukuqlkj Hkh fy[k ldrs gSa& Program public class ForLoop { public static void main(String args[]) { for(int i=1; i<=7; i++) { System.out.println(i); } } }


Java in Hindi Assignment Operators tSls gesa 1 ls 20 rd dh dsoy le la[;k,a gh Screen ij Print djokuh gks vkSj ge Loop dks ,d ds Øe esa pyk,a rks gesa if condition dks Use djds ;s dke djuk gksxk fd ;fn Print gksus okyk eku 2 ls iwjh rjg HkkT; gS] rks ogh la[;k Print gks “ks’k ughaA bl izdkj dk izksxzke cukus ls izksxzke dk Loop iwjs 20 ckj pysxkA tcfd ;gh dke ge Looping Statement ds varxZr Assignment Operator dk iz;ksx djds dj ldrs gSa] ftlesa Loop dk izkjfEHkd eku 0 dj nsuk gksxk vkSj Loop dks ,d ds Øe esa uk c es vk tk,xh fd fdl izdkj ls Increment ;k Decrement Operator ds LFkku ij izksxzke dh t:jr dks le>rs gq, Assignment Operators dk iz;ksx fd;k tk ldrk gSA ;fn gesa fdlh Variable ds eku esa Øe ls dksbZ vU; la[;k tksMuh ;k ?kVkuh gks rks] ge bls fuEukuqlkj Hkh fy[k ldrs gSaA ekuk x = 10

gS rks

Mathematical Expression x=x%3 x=x+2 x=x+6 x=x–3 x=x*2 x=x/5

“C” Expression x %= 3 x += 2 x += 6 x -= 3 x *= 2 x /= 5

Output x=1 x=4 x=8 x=7 x = 20 x=2

izFke Expression esa x ds eku 10 es 3 dk Hkkx fn;k x;k gS vkSj izkIr “ks’kQy dks okil x esa store dj fn;k x;k gSA x %=3 dk ;gh eryc gS fd x ds eku es 3 dk Hkkx nsdj og eku okil x dks iznku dj nksA nwljs Expression esa x dk eku nks c
Java in Hindi ikapos Expression es ;s crk;k x;k gS fd x ds eku dks 2 ls xq.kk djds izkIr gksus okys eku dks iqu% x dks ns fn;k tk,A bl Expression dks Hkh ge Looping esa Use dj ldrs gSaA NBs Expression dk ;s vFkZ gS fd x ds eku esa 5 dk Hkkx fn;k tk, o tks HkkxQy izkIr gksrk gS] mls iqu% x esa Hkst fn;k tk,A x /= 5 blh Statement dk laf{kIr :i gSA Expression ds :i esa “C” izksxzke esa mij crk, x, nksuksa gh rjg ds Expression lgh gSa vkSj izksxzke nksuksa dks ekU;rk nsrk gSA ge gekjs izksxzke esa bu nksuksa esa ls fdlh Hkh rjg ds Expression

dk mi;ksx dj ldrs gSaA

Nesting of Loop ftl rjg geus if Conditionals Statements dh Nesting dh Fkh mlh rjg ls ge Loops Hkh Nesting dj ldrs gSaA ;kuh dbZ ckj izksxzke esa ,slh t:jrsa gksrh gSa] fd ml [kkl dke Loop dh lk/kkj.k izfØ;k }kjk ugha dj ldrsA rc gesa ,d Loop ds vanj ,d vU; Loop Use djuk iMrk gSA tc fdlh Loop esa okil Loop dk iz;ksx fd;k tkrk gS rks bls Loop Nesting djuk dgrs gSaA

dh dks dks dh

Nesting of for Loop For Loop dh tc Nesting dh tkrh gS rc geas”kk Outer Loop, Inner Loop dks Control djrk gSA Outer Loop Row ds fy;s o Inner Loop Column ds fy;s fy[kk tkrk gSA bldk Syntax fuEukuqlkj gksrk gS&

Definition of Nesting of for Loop tc Program Control, Outer for Loop ij vkrk gS rc check djrk gS fd Outer For Loop dh Condition lR; gS ;k ughaA ;fn Outer For Loop dh Condition lR; gksrh gS] rks Program Control Inner Loop esa izos”k djrk gSA ;gka Program Control dks ,d vkSj for Loop feyrk gS vkSj izksxzke Control bl for dh Condition dks check djrk gSA ;fn Inner for Loop dh Condition lR; gksrh gS rks Inner for Loop Iterate gksrk gS vkSj ;s Inner Loop rc rd Iterate gksrk jgrk gS tc rd fd Inner Loop dh Condition lR; gksrh gSA


Java in Hindi tSls gh inner Loop dh Condition vlR; gksrh gS] izksxzke Control okil Outer Loop dks check djrk gSA ;fn okil Outer Loop dh Condition lR; gks tkrh gS rks Program Control iqu% inner Loop esa izos”k djrk gS vkSj iqu% Inner Loop dk rc rd Iteration gksrk gS tc rd fd Inner Loop dh condition vlR; ugha gks tkrhA Program Control bUgha nksuksa Loops ds chp rc rd Iterate gksrk jgrk gS tc rd fd nksuksa Loops dh Condition vlR; uk gks tk,A ;fn Outer Loop dh Condition igyh ckj esa gh vlR; gks tk, Execution gh ugha gksrk gSA Inner Loop dk Execution rHkh gksrk gS Condition lR; gksA Loop dh Nesting dks le>us ds fy;s vkxs ,d blls for Loop dh nesting o mlds dke djus rjhds dks vPNh rjg ls

rks Inner Loop dk tc Outer Loop dh izksxzke cuk;k x;k gSA le>k;k x;k gSA

Example :

,d ,slk izksxzke cukvks tks fuEu Format dks print djsA * ** *** **** *****

bl izksxzke esa nks for Loop pyk, x, gSa vkSj Condition bl izdkj dh j[kh xbZ gS fd Inner Loop mruh gh ckj pys ftruk ckgj dk Loop pykus okys Variable dk eku gksA izksxzke fuEukulkj gS% Program public class ForLoopNested { public static void main(String args[]) { for(int i=1; i<=5; i++) { for(int j=1; j<=i; j++) { System.out.print(" * "); } System.out.println(); } } } Output

* * * * *

* * * *

* * *

* *

*


Java in Hindi tc fdlh Statement dh Nesting dh tkrh gS rc Inner Most Control Statement igys Execute gksrk gS vkSj fQj Øe ls Outer Control Statements Execute gksrs gSaA tc ;s Program Run fd;k tkrk gS] rc lcls igys Program Control Outer Loop esa igqaprk gSA Outer Loop dh Condition true gksrh gS D;ksafd i dk eku 1 ls de gSA blfy, Program Control Outer Loop ds Statement Block esa izos”k djrk gSA Statement Block esa fQj ls ,d Loop izkIr gksrk gSA ;s Loop Hkh True Return djrk gS] D;ksafd Inner Loop ds Variable j dk eku i ds eku 1 ds cjkcj gSA bl fLFkfr es Program Control Inner Loop ds Statement Block esa izos”k djrk gS vkSj ,d * Print djrk gSA pwafd ge pkgrs gSa fd * Print gksus ds ckn Hkh gesa New Line izkIr uk gks] blfy, geus bl Block esa out Object ds print() Method dk iz;ksx fd;k gSA Inner Loop ds Statement Block dk Execution gksus ds ckn j dk eku Increment gks dj 2 gks tkrk gSA pwafd i dk eku 1 gS vkSj j dk eku 2 gS] blfy, j dk eku i ds eku ls NksVk ;k

cjkcj ugha gSA

bl fLFkfr esa Inner Loop false Return djrk gSA tc Inner Loop False gks tkrk gS] rc Program Control Outer Loop ds Variable i dk eku Increment djds 2 dj nsrk gSA pwafd i dk eku vHkh Hkh 5 ls de gS blfy, Outer Loop dh Condition true gksrh gS vkSj Program Control Outer Loop ds Statement Block esa igqaprk gS] tgka mls fQj ls Inner Loop izkIr gksrk gSA pwafd Inner Loop ds Looping Variable dks geus Inner Loop ds Parenthesis esa gh Declare fd;k gS] blfy, tc Program Control bl Inner Loop esa izos”k djrk gS rc Inner Loop ds Variable dks Create djrk gS vkSj tc Program Control Inner Loop ls ckgj fudyrk gS] rc Inner Loop ds Variable dks Destroy dj nsrk gSA blfy, ftruh ckj Hkh Program Control Outer Loop ds Statement Block esa vkrk gS] os Inner Loop ds Variable dks fQj ls Create djrk gSA ,slk djus ds dkj.k Inner Loop ds Variable dk eku okil ,d gks tkrk gS D;ksafd Inner Loop dk Variable Create gksus ds ckn fQj ls Initialize gksrk gSA pwafd Inner Loop ds Variable j dk eku fQj ls 1 gks x;k gS vkSj ;s eku Outer Loop ds Variable i ds eku ls de gS] blfy, Loop Execute gksrk gS vkSj ubZ Line esa ,d * Print djrk gSA fQj j dk eku Increment gksdj 2 gks tkrk gSA ;s eku 2 i ds eku ds cjkcj gS] blfy, Inner Loop fQj ls Execute gksrk gS vkSj ,d vkSj * Print djrk gSA tc rhljh ckj Inner Loop ds Variable j dk Increment gksrk gS] rc j dk eku i ds eku ls T;knk gks tkrk gS vkSj Program Control Inner Loop ls ckgj fudyrk gSA ogka mls ,d println() Method feyrk gSA ;s Method dsoy ,d New Line iznku djrk gSA blds ckn i ds eku dk Increment gksdj i dk eku 3 gks tkrk gSA pwafd i dk ;s eku Hkh 5 ls NksVk gS] blfy, Outer Loop fQj ls Execute gksrk gSA Inner Loop ds Variable dk eku okil 1 gks tkrk gSA bl fLFkfr esa vc Inner Loop rhu ckj Execute gksrk gS vkSj rhu * Print djrk gSA


Java in Hindi ;s izfØ;k rc rd pyrh jgrh gS] tc rd fd Outer Loop ds Variable i dk eku 6 ugha gks tkrkA tSls gh i dk eku 6 gks tkrk gS] Outer Loop false Return djrk gSA ftlls Program Control Outer Loop ds Statement Block esa izos”k gh ugha djrk vkSj lh/ks gh Program ds vUr ij igqap tkrk gSA bl rjg ls bl Program esa ge ns[k ldrs gSa] fd Inner Loop dk Execution mlds Outer Loop dh Condition ij fuHkZj djrk gSA ;fn Outer Loop Execute gksrk gS rks gh Inner Loop Execute gksrk gSA for Loop dk T;knkrj iz;ksx fdlh Array ds fofHkUu Index Number ij fLFkr ekuksa dks izkIr djus ds fy, fd;k tkrk gSA fiNys v/;k; esa geus ,d Array esa Stored ekuksa dks dbZ Statements }kjk Screen ij Print fd;k FkkA mlh Program ds Array ds fofHkUu ekuksa dks ge fuEukuqlkj Loop ds iz;ksx ds }kjk Hkh Access dj ldrs gSaA Program public class ArrayWithLoop { public static void main(String args[]) { String name[] = new String[6]; name[0] = "Balaji" ; name[1] = "Madhav" ; name[2] = "BalGopal" ; name[3] = "Nandlal" ; name[4] = "BalKishan" ; name[5] = "ManMohan" ;

}

}

for(int i=0; i<=5; i++) { System.out.println("Name in Array at Index Number ["+i+"] = " + name[i]); }

Output Name in Array at Index Number [0] = Balaji Name in Array at Index Number [1] = Madhav Name in Array at Index Number [2] = BalGopal Name in Array at Index Number [3] = Nandlal Name in Array at Index Number [4] = BalKishan Name in Array at Index Number [5] = ManMohan

tSlkfd geus igys gS] blfy, gesa tks Program esa tc Screen ij Print

Hkh dgk fd fdlh Hkh Array ds igys Index Number dk eku gesa”kk 0 gksrk Loop Array ds fy, Use djuk gksrk gS] mls gesa”kk 0 ls “kq: djrs gSaA bl i dk eku 0 gksrk gS rc Array ds Index Number 0 ij fLFkr String gksrh gSA tc i dk eku 1 gksrk gS] rc Array ds Index Number 1 ij fLFkr


Java in Hindi String Screen ij Print gksrh gSA blh rjg ls Array dh fofHkUu Strings Output esa Print

gksrh gSA

tc ge fdlh 2-D Array ds fofHkUu Data Elements dks Loop }kjk Access djuk pkgrs gSa] rks gesa nks Inner Loops dk iz;ksx djuk iMrk gSA blh rjg ls ;fn gesa 5-D Array ds fofHkUu Data Elements dks Access djuk gks] rks gesa ikap Inner Loop pykus gksrs gSaA geus fiNys v/;k; esa ftl 2-D Array dks lkekU; Statement }kjk Access fd;k Fkk ;fn ge mlh Array dks Loop }kjk Access djuk pkgsa] rks ;s dke ge fuEukuqlkj dj ldrs gSa& Program public class TableWithArray { public static void main(String args[]) { int table[][] = new int[4][3]; table[0][0] = 10 ; table[0][1] = 20 ; table[0][2] = 30 ; table[1][0] = 50 ; table[1][1] = 46 ; table[1][2] = 20 ; table[2][0] = 2 ; table[2][1] = 12 ; table[2][2] = 30 ; table[3][0] = 93 ; table[3][1] = 39 ; table[3][2] = 3 ;

}

}

for(int i=0; i<4; i++) { for(int j=0; j<3; j++) { System.out.println("Value in Array at Index Number [“ +i+ “][“ +j+ “] = " + table[i][j]); } }

Output Value in Array at Index Number [0][0] = 10 Value in Array at Index Number [0][1] = 20 Value in Array at Index Number [0][2] = 30 Value in Array at Index Number [1][0] = 50 Value in Array at Index Number [1][1] = 46 Value in Array at Index Number [1][2] = 20 Value in Array at Index Number [2][0] = 2 Value in Array at Index Number [2][1] = 12


Java in Hindi Value in Array at Index Number [2][2] = 30 Value in Array at Index Number [3][0] = 93 Value in Array at Index Number [3][1] = 39 Value in Array at Index Number [3][2] = 3

fdlh 2-D Array esa Outer Loop gesa”kk ROW dks Represent djrk gS vkSj Inner Loop COLUMNS dks Represent djrk gSA pwafd gekjh Table esa ROWS dh la[;k 4 gS blfy, Outer Loop dks pkj ckj pykuk t:jh gS vkSj COLUMNS dh la[;k 3 gS blfy, Inner Loop dks rhu ckj pyk;k gSA lkFk gh Array ds Index Numbers dh “kq:vkr gesa”kk 0 ls gksrh gS] blfy, Loop ds izkjfEHkd eku dks 0 Initialize fd;k gSA while Loop For Loop dh rjg ;g Hkh fdlh Statement ds nksgjkus dk dke djrk gS] ysfdu fQj Hkh ;g for Loop ls dkQh vyx gSA bl Loop esa Java ds Keyword while dk iz;ksx fd;k tkrk gSA while Loop esa while dks’Bd esa dsoy Condition nh tkrh gSA Variable dk izkjafHkd eku o Step Size while ds dks’Bd dk fgLlk ugha gksrs gSa] cfYd Variable dk izkjafHkd eku while Loop dks “kq: djus ls igys gh Declare o Initialize dj fn;k tkrk gS vkSj Loop dh Step Size while Condition ds Statement Block dk fgLlk gksrh gSA while Loop dk syntax fuEukuqlkj gksrk gS% Variable Declaration; Value Initialization; while(Condition ) { Statement Block; Step Size; } Statement 1; while Statement ds dks’Bd ds ckn dHkh Hkh ; (Semi Colon) dk iz;ksx ugha fd;k tkrk gSA tc while ds ckn dsoy ,d gh Statement dk Execution djuk gksrk gS] rc gesa ea>ys

dks’Bd dk iz;ksx djus dh t:jr ugha jgrh gSA fQj Hkh ;fn ea>ys dks’Bd dk iz;ksx dj fy;k tk, rks dksbZ QdZ ugha iMrk gSA

Control Flow in while Loop LkoZizFke gesa Loop pykus okys Variable dks izkjafHkd eku nsuk gksrk gSA ;g dke while Loop ds ckgj gh dj fy;k tkrk gSA tc Program Control, while Loop esa izos”k djrk gS rks Program Control, Condition Check djrk gSA ;fn Condition lR; gksrh gS rks Program Control while Loop ds Statement Block esa izos”k djrk gS vkSj Statement Block dk Execution djrk gSA Execution ds ckn Statement Size r; djrk gS] ;kuh Loop ds Variable dk eku t:jr ds vuqlkj Increment ;k Decrement djrk gSA

;g Øe rc rd pyrk jgrk gS tc rd fd while Condition vlR; ugha gks tkrh gSA ;fn Condition lR; ugha gksrh gS rks Program Control while Loop ds Statement Block esa izos”k ugha djrk] cfYd lh/ks gh Statement 1 ij pyk tkrk gSA


Java in Hindi Example : While Loop dk iz;ksx djrs gq, ,d ,slk izksxzke cukvks ftlesa 1 ls 100 ds chp og la[;k Print gks ftlesa 2 o 3 dk iwjk&iwjk Hkkx tkrk gSA Program Definition & fdlh Hkh Loop dks pykus ds fy;s Loop dh vko”;d rhuksa ckrsa gesa irk gksuh pkfg,A igyh ckr ;s fd Loop dk izkjaHk dgka ls gksxk] nwljk ;s fd Loop dk var dgka gksuk gS vkSj rhljk ;s fd Loop dks fdl Øe esa Increase ;k Decrease djuk gSA fdlh Hkh Loop esa fdlh Variable }kjk ;s rhuksa ckrsa r; dh tkrh gSaA

bl izksxzke esa Hkh ,d Variable x fy;k x;k gS rkfd ;s rhuksa eku izkIr fd;s tk ldsaA bl izksxzke esa gesa 1 ls 100 ds chp dh la[;kvksa ij izfØ;k djuh gS blfy;s Loop ds Variable dk izkjafHkd eku 1 o vafre eku 100 Define fd;k x;k gS vkSj Step Size dks ,d ds Øe esa gh c
iwjk&iwjk Hkkx tkrk gSA bl “krZ dks ;fn ge /;ku ls le>sa rks ;s dg ldrs gSa fd bl ,d “krZ esa nks “krZ gSA igyh ;s fd fdlh la[;k esa 2 dk Hkkx iwjk&iwjk tkuk pkfg;s vkSj nwljh ;s fd mlh la[;k esa 3 dk Hkkx Hkh iwjk&iwjk tkuk pkfg;s rHkh og Condition iw.kZ :i ls lR; gksxhA bl “krZ dks ;fn ge nwljs “kCnksa esa dgsa rks dg ldrs gSa fd fdlh la[;k esa ;fn 2 dk Hkkx nsus ij “ks’k Qy “kqU; izkIr gksrk gS rks Condition lR; gksrh gSA ;fn bls xf.krh; :i esa fy[ksa rks x%2 == 0 fy[k ldrs gSaA lkFk gh mlh la[;k esa 3 dk Hkkx Hkh iwjk&iwjk tkuk pkfg;s ;kuh mlh la[;k esa 3 dk Hkkx nsus ij Hkh “ks’kQy “kwU; vkuk pkfg;s bls Hkh xf.krh; :i esa x%3 = = 0 fy[k ldrs gSaA bl izdkj nksuksa Condition lR; gksus ij gh Statement Block dk Execution gksuk pkfg;sA vr% bu nksuks Condition dks Logical Operator AND ( && ) }kjk tksM dj if dks’Bd esa fy[kuk gksxkA bl izdkj bl Loop dh okLrfod Condition x % 2 = = 0 && x % 3 = = 0 gksxhA bl izdkj gesa bl izksxzke dh lHkh vk/kkjHkwr phtsa izkIr gks tkrh gSa tks fuEukuqlkj gSa& 1 2

3

Loop ds Variable dk izkjafHkd eku ftlls Loop dk Iteration “kq: gksxk ;kuh 1 Loop ds Variable dk vafre eku ftlds ckn Loop dk Iteration :d tk,xk] ;kuh 100 Loop ds Variable dh Step Size ftl Øe esa Loop ds Variable dk increment

gksxkA


Java in Hindi 4 ,d if Condition ftlesa ;s check gksxk fd 1 ls 100 ds chp dkSulh la[;k,a gSa ftuesa 2 o 3 nksuksa dk Hkkx iwjk&iwjk tkrk gSA bl Discussion ds vk/kkj ij ge fuEukuqlkj while Loop dk iz;ksx djds bl leL;k dks gy dj ldrs gS:a Program public class DivisionWithReminder { public static void main(String args[]) { int x = 1; while(x<=100) { if(x%2 == 0 && x%3 == 0) { System.out.print(“\t” + x); } x++; } } } Output 6 12 18 24 30 36 42 48 54 60 66 72 78 84 90 96

lkekU;r;k bl Loop dk iz;ksx ge rc djrs gSa] tc gesa ;s irk ugha gksrk gS fd Loop ds Statement Block dks fdruh ckj Execute djuk gSA tcfd for Loop dk iz;ksx ge rc djrs gSa tc gesa irk gksrk gS fdlh for Loop ds Statement Block dk iz;ksx fdruh ckj djuk gSA

do while Loop ;g Java esa iz;ksx gksus okyk rhljk o vafre Loop gSA blesa Hkh vU; Loop dh rjg gh rhuksa vk/kkjHkwr Statements dh t:jr gksrh gS ;kuh Loop ds Variable dk izkjafHkd eku] vafre eku o Step Size. bl Loop dh fo”ks’krk ;s gS fd bl esa check gksus okyh Condition Loop ds var esa check gksrh gSA ;kuh tc gesa ,slh t:jr gks fd izksxzke esa Loop ds Statement ;k Statement Block dk Execution de ls de ,d ckj rks djuk gh gks] rc ge bl Loop dk iz;ksx djrs gSaA bl Loop dk syntax fuEukuqlkj gS& Variable Declaration; Value Initialization; do {

Statement Block; Step Size; }while(Condition); 178 Any Question or Suggestion, Just Discuss Here...

Java in Hindi Statement 1;

bl Loop dh “kq:vkr do key word ls gksrh gS vkSj Statement Block ds ckn ea>yk dks’Bd can djus ds ckn while Condition nh tkrh gSA lkFk gh ;gh ,d Loop gS] ftlesa while ds Condition dks’Bd ds ckn ; (Semi Colon ) dk iz;ksx fd;k tkrk gSA do ds ckn dksbZ Hkh Colon ;k Semi Colon iz;kssx ugha fd;k tkrk gSA bl Loop esa izksxzke Control dks tSls gh do Key word feyrk gS rks Program Control lh/ks gh do ds Statement Block esa pyk tkrk gS vkSj mlesa fy[ks Statements dks Execute dj nsrk gSA faQj Loop pykus okys Variable dk Step Size Increase ;k Decrease izksxzke ds vuqlkj djrk gSA Program Control tc bl Block ls ckgj vkrk gS rc mls while Condition izkIr gksrh gSA ;gka ;fn Condition lR; gksrh gS rks Program Control do ls okil Statements dk Execution djrk gS vkSj ;fn Condition vlR; gksrh gS] rks Program Control Loop dks okil Iterate ugha djrk cfYd lh/ks gh Statement 1 ij pyk tkrk gSA for Loop dks ge while Loop dh rjg Hkh Use dj ldrs gSaA ;fn ge fiNys Program dks for Loop ls gh gy djuk pkgsa vkSj lkFk gh ;s Hkh pkgsa fd for Loop dks while Loop dh rjg gh Use djsa] rks ge ;s dke djus ds fy, for Loop dks fuEukuqlkj Use djrs gq, mijksDr Program fy[k ldrs gSa& Program public class DivisionWithReminder { public static void main(String args[]) { int x = 1; for( ; x<=100 ; ) { if(x%2 == 0 && x%3 == 0) { System.out.print(“\t” + x); } x++; } } }

ge fofHkUu izdkj ds Loops dh Hkh mlh izdkj ls Nesting dj ldrs gSa] ftl rjg ls for Loop dh dj ldrs gSaA ;kuh ge fdlh leL;k ds lek/kku ds fy, fdlh Hkh Loop dk iz;ksx dj ldrs gSaA

;s gekjh lqfo/kk ij fuHkZj djrk gS fd ge fdlh leL;k ds lek/kku ds fy, fdl Loop dk iz;ksx djrs gSaA fofHkUu Loops dks ,d nwljs ds izfrLFkkiu ds :i esa Use fd;k tk ldrk gS vkSj ge fdlh Hkh dke dks rhuksa gh Loops }kjk leku izdkj ls lEiUu dj ldrs gSaA


Java in Hindi Jump Statements

tkok esa rhu rjg ds Jump Statements gSa ftudk iz;ksx djds ge gekjs Program esa fdlh Hkh Statement ij Jump dj ldrs gSaA break Statement bl Statement dk iz;ksx ge nks LFkkuksa ij dj ldrs gSaA igyk iz;ksx geus switch Statement esa ns[k fy;k gSA ge fiNys Programs esa ns[k ldrs gSa Loop ds Iteration ds le; Loop ds Block Statements dk nksgjku rc rd gksrk jgrk gS] tc rd fd Loop dh Condition lR; gksrh gSA ysfdu dbZ ckj gekjs lkeus ,slh ifjfLFkfr vk tkrh gS fd fdlh [kkl dke ds fy;s gesa Loop ds dqN Statements ds Execution dks NksM dj Loop ds chp esa ls gh ckgj vkuk gksrk gS] ml le; ge break Statement dk iz;ksx djrs gSaA ;s bl Statement dk nwljk iz;ksx gSA ge fdlh Loop esa tgka Hkh bl Statement dks fy[k nsrs gSa] Program Control lh/ks gh bl Statement ds feyrs gh Loop ls ckgj fudy tkrk gSA bls ,d Program }kjk le>us dh dksf”k”k djrs gSa& Program public class BreakStatement { public static void main(String args[]) { for(int i=0; i<10; i++) { if(i==5) { break; } System.out.print(“\t” + i); } System.out.println(“\nLoop is Terminated”); } } Output 0 1 2 3 4 Loop is Terminated

bl Program esa gkykafd geus Loop dks 10 ckj pyk;k gS] ysfdu tSls gh i dk eku 5 gksrk gS] Loop ds Statement Block esa fy[kk x;k if Statement true gks tkrk gS vkSj Program Control bl Statement Block esa izos”k djrk gS] tgka mls break Statement izkIr gSA ;s Statement izkIr gksrs gh Program Control Loop ls ckgj fudy tkrk gS vkSj Sequential Statement dks Print dj nsrk gSA


Java in Hindi bl Statement dk iz;ksx djds ge fdlh Hkh Statement ij Jump dj ldrs gSaA bls le>us ds fy, fuEu Program nsf[k,% Program public class BreakStatementJump { public static void main(String args[]) { boolean x = true; first: { second: { third: { System.out.println("Before the break statement."); if( x )

}

}

break second;

System.out.println("This statement will not Execute."); } System.out.println("This statement will not Execute."); } System.out.println("This Statement will Execute after second Block."); }

Output Before the break statement. This Statement will Execute after second Block.

bl Program esa geus rhu Statement Blocks cuk, gSaA ;s Statement Blocks fdlh Loop ds Hkh gks ldrs gSa vkSj lkekU; Block Hkh gks ldrs gSaA rhuksa Blocks esa geus ,d Label fn;k gSA Outer Most Block ls igys geus first Label fn;k gSA fQj Middle Block dk Label geus second fn;k gS vkSj Inner Most Block ls igys geus third Label fn;k gSA ,d ckr /;ku j[ksa fd Label ds ckn gesa”kk Colon dk iz;ksx gksrk gS uk fd Semi Colon dkA tc Program Control Inner Most Block esa igqaprk gS] rc mls fuEukuqlkj ,d Break Statement feyrk gS& if(x)

break second;

;kuh Program Control dks bl Statement ls ;s tkudkjh feyrh gS fd ;fn x dk eku true gS rks ml Block ls ckgj fudy tkuk gS] ftlesa second Label dks Define fd;k x;k gSA


Java in Hindi pwafd second Label nwljs Block dks Represent dj jgk gS] blfy, Program Control nwljs Block ls ckgj fudy tkrk gS vkSj rhljs Block ds Statement dk Execution dj nsrk gSA ifj.kke Lo:i gesa Output esa dsoy nks gh Statements izkIr gksrs gSaA tkok esa bl Statement dks “C” o “C++” ds goto Statement ds LFkku ij iz;ksx fd;k x;k gSA D;ksafd Java esa goto Statement dks Include ugha fd;k x;k gSA ;s Statement tkok esa os lHkh dke dj ldrk gS ftu dkeksa dks “C” o “C++” esa goto Statement ds iz;ksx }kjk fd;k tk ldrk FkkA continue Statement bl Statement dk iz;ksx rc fd;k tkrk gS] tc ge fdlh [kkl ifjfLFkfr esa Loop ds fdlh nksgjku esa Block ds Statements dks Execute djuk ugha pkgrs gSA /;ku nsa fd tgka break dk iz;ksx Program Control dks Loop ls gh ckgj fudky nsrk gS] ogka continue dk iz;ksx gesa Loop ls ckgj ugha fudkyrk cfYd dsoy ek= gesa Loop ds ml Iteration ls ckgj fudkyrk gSA uhps break o continue Statement ds iz;ksx ls izksxzke cuk;k x;k gS ftlls bUgs vklkuh ls le>k tk ldrk gSA Program public class BreakAndContinueStatement { public static void main(String args[]) { for(int i=0; i<10; i++) { if(i==5) { break; } System.out.print(“\t” + i); } System.out.println(“\nBreak Loop is Terminated”);

}

}

Output 0 1

for(int i=0; i<10; i++) { if(i==5) { continue; } System.out.print(“\t” + i); } System.out.println(“\nContinue Loop is Terminated”);

2

3

4


Java in Hindi Break Loop is Terminated 0 1 2 3 4 6 7 8 Continue Loop is Terminated

9

bl Program esa ge nksuksa Statements ds vUrj dks le> ldrs gSa] tgka Break Statement gesa ml le; Loop ls ckgj fudky nsrk gS] tc Loop ds Variable i dk eku 5 gksrk gSA ogha Continue Statement gesa dsoy Loop ds ml Iteration ls vxys Iteration esa Move dj nsrk gS] ftl Iteration esa Variable i dk eku 5 gksrk gSA return Statement ;s Statement fdlh Method ls Program Control dks Return djus ds fy, iz;ksx fd;k tkrk gSA main() Method dh rjg gh vkxs ge Lo;a ds User Defined Methods cukuk Hkh lh[ksaxsA ;s Methods Class ds Member Function ds :i esa Define fd, tkrs gSaA fdlh Method ls fdlh fo”ks’k fLFkfr esa dqN Statements dks fcuk Execute fd, gq,] tc Program Control dks Return gksuk gksrk gS] rc bl Statement dk iz;ksx fd;k tkrk gSA lkFk gh bl Statement dk iz;ksx fdlh Method ls fdlh eku dks return djokus ds fy, Hkh fd;k tk ldrk gSA bl Statement ds ckjs esa ge Methods dks le>rs le; Use djsaxsA

Drawing Graphics

gesa yxHkx lHkh Applets esa FkksMk cgqr Graphics Programming rks djuk gh iMrk gS] fQj pkgs ge Texts dh ,d Line Applet ij Display djus ds fy, Graphics Programming dk iz;ksx djsa ;k fQj pkgs Animation ds :i esa Graphics dh ,d Sequence Display djsaA D;ksafd Windows ,d GUI System gS] blfy, gesa Screen ij tks dqN Hkh fn[kkbZ nsrk gS] og lcdqN Graphically gh fn[kkbZ nsrk gSA ;gh ckr Texts ds lEca/k esa Hkh Apply gksrh gSA ;kuh Windows ;k GUI Mode esa gesa Screen ij tks Texts Hkh fn[kkbZ nsrs gSa] os Texts Hkh okLro esa Graphics gh gksrs gSaA

Applet Canvas fdlh Applet dk tks fgLlk gesa Screen ij fn[kkbZ nsrk gS] Applet ds ml fgLls dks Canvas dgrs gSa] ftlesa Applet fofHkUu izdkj dh Information ;kuh Texts o Graphics dks Display djrk gSA Applet ds Canvas dh Size Applet dh Size ij fuHkZj gksrh gSA ;kuh Applet ftruk cMk gksxk] Applet dk Canvas Hkh mruk gh cMk gksxkA Applet dh Size HTML Document ds Tag }kjk Specify fd;k tkrk gSA ge tks dqN Hkh Applet esa Draw djrs gSa] gesa ml Applet esa mruh gh Drawings fn[kkbZ nsrh gS] ftruh Canvas ij gksrh gSA Applet dk tks Area Canvas ls ckgj gksrk gS] og Area gesa fn[kkbZ ugha nsrk gSA mnkgj.k ds fy, fuEu Applet nsf[k,] ftlesa ,d Text String dks Display

fd;k x;k gS%


Java in Hindi

bl Applet esa ftruh Screen fn[kkbZ ns jgh gS] og Screen gh Applet dk Canvas gS] tcfd Applet dh Size rks blls T;knk Hkh gks ldrh gSA ;kuh Applet dh Actual Size fuEukuqlkj iwjh Text String dks Display dj ldrh gS%

ge Canvas ij tks Hkh Graphical Images Draw djrs gSa] mudh Position dks Pixel Locations Coordinate System ds vk/kkj ij Applet ij Identify djrs gSaA Screen ij gesa tks Hkh Graphics fn[kkbZ nsrk gS] og Monitor ij pedus okys Picture Elements gksrs gSa] tks ,d O;ofLFkr Øe esa pedrs gSa vkSj gesa dksbZ uk dksbZ Graphics fn[kkbZ nsrk gSA gesa gekjs fdlh Specific Graphics dks Applet ds fdl Pixel Location ls Draw djuk gS] bl Pixel Location dks r; djus dk ,d rjhdk gksrk gS] ftls Pixel Coordinate System dgrs gSaA Windows Operation System fofHkUu izdkj ds dbZ Mapping Modes dks Support djrk gSA ;s Mapping Modes gh ;s r; djrs gSa] fd fdlh Application ;k Applet Window ds fy, Coordinates fdl izdkj ls Calculate gksaxsA fdlh izdkj ds Hkh Confusion ls cpus ds fy, tkok esa dsoy ,d gh Coordinate System dks ekU;rk iznku fd;k x;k gSA bl Coordinate System esa fdlh Application ;k Applet Window ds Upper Left Corner dk eku (0,0) gksrk gS vkSj X-Axis dk eku Window ds Right dh rjQ c

Java in Hindi Colors tkok esa ge fofHkUu izdkj ds Colors esa fofHkUu izdkj ds Graphics o Texts dks Draw dj ldrs gSaA tkok esa RGB Mode esa fofHkUu Colors dks izkIr fd;k tk ldrk gS vkSj dqN Standard Color Constants dk iz;ksx Hkh fd;k tk ldrk gSA tkok esa gj Color dks Red, Green o Blue Components }kjk Define fd;k tkrk gSA ;s rhuksa Components ,d Integer izdkj ds eku }kjk Represent gksrs gSa vkSj budk eku 0 ls 255 ds chp dqN Hkh r; fd;k tk ldrk gSA ,d RGB Value dks ,d 32-Bit Integer esa Store fd;k tk ldrk gS] ftlesa 31 ls 24 rd ds High Order Bits Unused jgrs gSa] 23 ls 16 rd ds Bits }kjk Red Color Represent gksrk gS] 15 ls 8 rd ds Bits }kjk Green Color Represent gksrk gS vkSj 7 ls 0 rd ds Low Order Bits }kjk Blue Color dks Represent fd;k tkrk gSA tkok esa fofHkUu izdkj ds Colors dks fdl izdkj ls cuk;k tk ldrk gS vkSj fdl izdkj ls Colors esa fofHkUu izdkj ds Special Effects yk, tk ldrs gSa] bu lc ds ckjs esa vkxs foLrkj ls le>saxsA ysfdu ;fn gesa General Colors ds lkFk gh dke djuk gks] rks tkok esa dqN Color Constants dks Define fd;k x;k gSA bu Constants dk iz;ksx djds Hkh ge fdlh Color dks Set dj ldrs gSaA ;s Constants fuEukuqlkj gSa% black, darkGray, lightGray, pink, yellow,

BLACK, DARK_GRAY, LIGNT_GRAY, PINK, YELLOW

blue, gray, magenta, red,

BLUE, GRAY, MAGENTA, RED,

cyan, green, orange, white,

CYAN, GREEN, ORANGE, WHITE,

bu Color Constants dks ge gekjh Coding esa Color Set djus ds fy, Directly Use dj ldrs gSaA ;fn ge Applet ds Background o Foreground Color dks Set djuk pkgsa] rks gesa setBackground() o setForeground() Method dk iz;ksx djuk iMrk gSA ekuyks fd gesa gekjs Applet ds Background dk Color Blue o Foreground dk Color White pkfg,] rks blds fy, gesa Applet ds init() Method esa fuEukuqlkj Statement fy[kuk gksxk% setBackground(Color.blue); setForeground(Color.WHITE);

;fn gesa fdlh Particular Object ds fy, fdlh u, Color dks Set djuk gks rks gesa Graphics Class ds setColor() Method dks Use djuk gksrk gSA ekuyks fd gesa gekjs Applet esa Blue Color esa ,d Message Display djuk gSA bl fLFkfr esa gesa Default Black Color ds LFkku ij Blue Color dks Set djuk gksxkA ;s dke djus ds fy, ge setColor() Method dks fuEukuqlkj Use dj ldrs gSa] tgka g Graphics Class dk ,d Object gS% g.setColor(Color.BLUE);

tc ge fdlh Color dks Set dj nsrs gSa] rks og Color ftl LFkku ij Set fd;k tkrk gS] ml LFkku ls vkxs ds lHkh Statements ds fy, og Color Set gks tkrk gSA blfy, ;fn gesa fdlh ,d Object ds fy, gh Color dks Set djuk gks] rks Object dks Draw djus ds ckn ml fiNys Color dks fQj ls Set djuk t:jh gksrk gSA


Java in Hindi dbZ ckj gesa System ds Current Graphical Attributes ds ckjs esa tkuus dh t:jr iMrh gSA bl Information dks iznku djus ds fy, Hkh tkok esa getColor(), getFont() o getFontMetrics() uke ds rhu Methods gSaA buds ckjs esa ge vkxs foLrkj ls i
Drawing Shapes tkok dh Graphics Class esa fofHkUu izdkj ds Graphical Objects dks Draw djus ds fy,
pwafd ;fn ge gekjs Program esa awt Package ds dsoy Graphics Class dks gh Import djuk pkgrs gSa] rks gesa mijksDr Syntax Use djuk gksrk gS] ysfdu ;fn ge pkgrs gSa fd gekjs Program esa awt Package dh lHkh Classes Import gks tk,a] rks gesa fuEukuqlkj Syntax fy[kuk gksrk gS] import java.awt.*;

fdlh Applet ;k GUI Application dsoy Appropriate Method dks gh Arguments dks Pass djuk gksrk Coordinates dks Represent djrs

esa ;fn ge fdlh Shape dks Draw djuk pkgrs gSa] rks gesa Call djuk gksrk gS vkSj mlesa Method ds fy, Required gSA Methods esa Pass fd, tkus okys Arguments mu gSa] tgka ij gesa Shape dks Draw djuk gSA

Drawing Line and Rectangles Graphics Class esa ;fn lcls ljy dksbZ Shape gS] rks og Line gSA Line Draw djus ds fy, gesa tkok dh Graphics Class ds drawLine() Method dks Use djuk gksrk gSA bl Method esa gesa Argument ds :i esa pkj Integer eku iznku djus iMrs gSaA ;s pkj eku tksMs ds :i esa gksrs gSa tks Line ds Starting Point (x1, y1) o Ending Point (x2, y2) dks Represent djrs gSaA mnkgj.k ds fy, ;fn ge Coordinate (0,0) ls (12,30) rd dksbZ Line Draw djuk pkgrs gSa] rks gesa drawLine() Method dks Call djds fdlh Graphics Object g ds Reference esa fuEukuqlkj Arguments Pass djus gksrs gSa] tgka g og Graphics Object gSa] ftls paint() Method esa Pass fd;k tkrk gSA g.drawLine( 0, 0, 12, 30 );


Java in Hindi blh rjg ls dksbZ Rectangle Create djus ds fy, gesa drawRect() Method dks Graphics Object g ds lkFk Call djuk gksrk gSA bl Method esa Hkh gesa pkj gh Argument Pass djus gksrs gSa] ysfdu bl ckj pkjksa Arguments ds Meaning cny tkrs gSaA bl Method esa igys nks Arguments Rectangle ds Upper-Left Corner dks Represent djrs gSaA rhljk Argument Rectangle dh Width dks rFkk pkSFkk Argument Rectangle dh Height dks Represent djrk gSA ;kuh ;fn ge pkjksa Arguments dks (10, 20, 30, 40) fy[krs gSa] rks (10, 20) Rectangle ds Upper Left Corner dks Represent djrk gSA rhljk Argument 30 Rectangle ds Width dks rFkk pkSFkk Argument Rectangle dh Height dks Represent djrk gSA bls ge fuEu fp= }kjk le> ldrs gSaA

;fn gesa fdlh Solid Color ls Filled Rectangle Create djus dh t:jr gks] rks gesa drawRect() Method ds LFkku ij fillRect() Method dks Call djuk gksrk gSA bu nksuksa Method ds Arguments esa fdlh izdkj dk dksbZ vUrj ugha gksrk gS] vUrj dsoy buds uke esa o buds dke djus ds rjhds esa gh gSA ;kuh ge bl Method dks Hkh fuEukuqlkj Call dj ldrs gSa% g.fillRect(10, 20, 30, 40);

;fn ge ,slk Rectangle Create djuk pkgsa] ftlds Corners Rounded gksa] rks gesa drawRoundRect() o fillRoundRect() Methods dks Call djuk gksrk gSA bu Methods esa Rectangle ds pkj Arguments rks leku gh gksrs gSa] blds vykok nks Arguments vkSj gksrs gSa] tks Rectangle ds Corners dh Rounding Limit r; djrs gSaA ;kuh ge bu Methods dks fuEukuqlkj Call dj ldrs gS% g.drawRoundRect(10, 20, 30, 40, 10, 10); g.fillRoundRect(10, 20, 30, 40, 5, 5);

Drawing Circles and Ellipses Graphics Class esa Circles o Ellipse dks Draw djus ds fy, vyx ls dksbZ Method ugha gSaA gesa Circles o Ellipses dks Draw djus ds fy, drawOval() Method dk gh iz;ksx djuk gksrk gSA ;kuh ge bl Method esa Arguments ds ekuksa esa ifjorZu djds Circles, Ellipses o Oval rhuksa gh izdkj ds Shapes Create dj ldrs gSaA Ovals Rectangles dh rjg gh gksrs gSaA ge


Java in Hindi bUgsa Rounded Corner Rectangles gh eku ldrs gSaA drawOval() Method esa Hkh gesa drawRect() Method dh rjg gh pkj Arguments Pass djus gksrs gSaA ;fn ge Oval ds Height o Width nksuksa dh Size leku j[krs gSa] rks cuus okyk Shape Circle gksrk gSA ;fn ge Oval, Circle ;k Ellipse dks vyx Color ls Fill djuk pkgrs gSa] rks gesa setColor() Method }kjk okafNr Color Set djuk gksrk gS vkSj mlds ckn drawOval() Method ds LFkku ij fillOval() Method dks Call djuk iMrk gSA Drawing Arcs Arc Oval dk gh ,d fgLlk gksrk gSA okLro esa fdlh Oval dks dbZ Arcs dh ,d yxkrkj J`a[kyk ds :i esa Hkh Represent fd;k tk ldrk gS] tks fd vkil esa Connected jgrs gSaA drawArc() Method 6 Arguments ysrk gSA igys pkj Arguments Oval dh rjg gh Arc dh Height o Width dks Specify djus ds fy, gksrs gSaA ikapok Argument Arc ds Starting Angle ds eku dks r; djrk gS] tcfd vfUre Argument Degree, Slop ;k Sweep Angle dks Represent djrk gSA Arcs dks Draw djrs le; okLro esa tkok igys ,d Oval gh Create djrk gS] mlds ckn vfUre nks Arguments ds :i esa fn, x, eku ds vk/kkj ij Oval dks Arc ds :i esa Change dj nsrk gSA Arcs dks Clockwise o Anti-Clockwise nksuksa rjg ls Represent fd;k tk

ldrk gSA

Drawing Polygons Polygons dbZ Hkqtkvksa okys Shapes gksrs gSaA Polygons dks ge dbZ Connected Lines dk ,d lewg dg ldrs gSa] tgka igyh Line ds vUr ls nwljh Line tqM tkrh gS] nwljh Line ds vUr ls rhljh Line o vfUre Line dk vUr okil ls igyh Line ds Starting Point ij gksrk gSA ;kuh ge ;s Hkh dg ldrs gSa fd ;fn gesa Polygon cukuk gks] rks ge drawLine() Method dks n ckj Use djds n Hkqtkvksa okyk Polygon Create dj ldrs gSaA mnkgj.k ds fy, fuEu paint() Method Applet ij ,d Polygon Draw djrk gS] ysfdu blesa geus dsoy drawLine() Method dk iz;ksx djds gh Line dks Draw fd;k gSA public void paint(Graphics g) { g.drawLine(50,50, 190,90); g.drawLine(190,90, 230, 190); g.drawLine(230,190, 50,50); } Polygon cukus ds fy, gesa drawPolygon() Method Use djuk gksrk gSA bl Method esa rhu Arguments Pass fd, tkrs gSaA igys nks Arguments nks Integer izdkj ds Array gksrs gSaA tcfd rhljk Argument dqy Hkqtkvksa dh la[;k dks Represent djrk gSA


Java in Hindi ;fn ge mijksDr Polygon dks drawPolygon() Method ls Draw djsa] ftls fd geus drawLine() Method ls Create fd;k gS] rks ;s dke djus ds fy, gesa paint() Method dks fuEukuqlkj fy[kuk iMsxk% public void paint(Graphics g) { int xPoints [] = {50,190, 230, 50}; int yPoints [] = {50, 90, 190, 50}; int nPoints = xPoints.length; }

g.drawPolygon(xPoints, yPoints, nPoints);

fiNys paint() Method dks ns[ksa rks ge le> ldrs gSa] fd Line ds Starting o Ending Points Horizontally (X,Y) ds Combinations gSa] tcfd bl paint() Method esa os gh Points Vertically Assembled gSa rFkk Starting o Ending Points dsoy ,d gh ckj Use fd, x, gSaA fdlh Hkh Polygon ds xPoints o yPoints nksuksa Arrays dh Size gesa”kk leku gksrh gS vkSj fdlh Array dh Size Kkr djus ds fy, ge length() Method dk iz;skx dj ldrs gSaA Program // File Name: AllGraphicsShapesApplet.java import java.awt.*; import java.applet.*; public class AllGraphicsShapesApplet extends Applet { TextField txtShape = new TextField("0"); int intShapeChoice; public void init() { add(txtShape); } public void paint(Graphics g) { g.drawString(" 1. For Line", 10, 60); g.drawString(" 2. For Rectangle", 250, 60); g.drawString(" 3. For Filled Rectangle", 10, 80); g.drawString(" 4. For Rounded Rectangle", 250, 80); g.drawString(" 5. For Filled Rounded Rectangle", 10, 100); g.drawString(" 6. For Oval", 250, 100); g.drawString(" 7. For Filled Oval", 10, 120); g.drawString(" 8. For Arc", 250, 120); g.drawString(" 9. For Filled Arc", 10, 140); g.drawString("10. For Polygon", 250, 140);


Java in Hindi g.drawString("11. For Filled Polygon", 10, 160); String shapeChoice = txtShape.getText(); try {

intShapeChoice = Integer.parseInt(shapeChoice); if(intShapeChoice < 1 || intShapeChoice > 12) g.drawString("Enter a Valid Shape Number between 1 to 11",260,40); else { if(intShapeChoice == 1) { setBackground(Color.blue); g.setColor(Color.white); g.drawLine(10,340, 400 , 340); } else if(intShapeChoice == 2) { setBackground(Color.cyan); g.setColor(Color.red); g.drawRect(10,340, 400 ,50); } else if(intShapeChoice == 3) { setBackground(Color.darkGray); g.setColor(Color.green); g.fillRect(10,340, 400 ,50); } else if(intShapeChoice == 4) { setBackground(Color.gray); g.setColor(Color.yellow); g.drawRoundRect(10, 340, 400 ,50, 45, 45); } else if(intShapeChoice == 5) { setBackground(Color.green); g.setColor(Color.yellow); g.fillRoundRect(10,340, 400, 50, 30, 30); } else if(intShapeChoice == 6)


Java in Hindi {

}

setBackground(Color.lightGray); g.setColor(Color.red); g.drawOval(20, 340, 200, 120);

else if(intShapeChoice == 7) { setBackground(Color.magenta); g.setColor(Color.green); g.fillOval(20, 340, 200, 120); } else if(intShapeChoice == 8) { setBackground(Color.orange); g.setColor(Color.white); g.drawArc(20, 340, 200, 120, 45, 45); } else if(intShapeChoice == 9) { setBackground(Color.pink); g.setColor(Color.blue); g.fillArc(20, 340, 200, 120, 45, 45); } else if(intShapeChoice == 10) { setBackground(Color.red); g.setColor(Color.white); int xPoints[] = {10, 440, 10, 10}; int yPoints[] = {340, 440, 180, 340}; int nPoints = xPoints.length; g.drawPolygon(xPoints, yPoints, nPoints); } else if(intShapeChoice == 11) { setBackground(Color.yellow); g.setColor(Color.red); int xPoints[] = {10, 440, 10, 10}; int yPoints[] = {340, 440, 180, 340}; int nPoints = xPoints.length; g.fillPolygon(xPoints, yPoints, nPoints); } else {


Java in Hindi

}

}

}

}

setBackground(Color.white); g.drawString("Enter a Valid Shape Number", 260, 40);

} catch(Exception ex) { g.drawString("Enter a Valid Shape Number", 260, 40); }

public boolean action(Event evnt, Object obj){ repaint(); return true; }

bl ,d gh Applet Program }kjk geus fofHkUu izdkj ds Shapes dks vyx&vyx Fill Color o vyx&vyx Background Color }kjk Draw fd;k gSA lkFk gh bl Program }kjk ge ;s Hkh le> ldrs gSa fd fdl izdkj ls ge if Control Statement dks Hkh Applet esa Use dj ldrs gSa vkSj t:jr ds vk/kkj ij Program ds Control dks fdlh ,d Point ls fdlh nwljs Point ij Hkst ldrs gSaA

bl Program dks Run djus ij gesa fuEukuqlkj ,d Applet fn[kkbZ nsrk gS] ftlesa ,d Text Box o dqN Options fn[kkbZ nsrs gSaA User ftl Option ds Number dks Text Box esa Type djds Enter Key Press djrk gS] ml Number ls lEcaf/kr Shape Applet esa Draw gks tkrk gSA


Java in Hindi blh rjg ls ge fdlh Applet esa fdlh Drawing dks fofHkUu Fill Colors esa Draw djus ds fy, Loop Control Statement dk Hkh iz;ksx dj ldrs gSaA bl dke dks ge fuEu Program }kjk iwjk dj ldrs gS%a Program // File Name: ForLoopApplet.java import java.awt.*; import java.applet.*; public class ForLoopApplet extends Applet { public void paint(Graphics g) { Color newColor = new Color(0,0,0);

}

}

for(int i=0; i<10; i++) { newColor = new Color(i*20+55, 0, 0); g.setColor(newColor); g.fillRect(i * 40, i * 10, 30, 60); }

Output

bl izdkj ls ge vU; Control Statements dks Hkh viuh t:jr ds vuqlkj GUI Programming esa Use dj ldrs gSa vkSj fofHkUu izdkj ds GUI Applications Develop dj

ldrs gSaA

Building Graphical User Interface

vHkh rd geus ftrus Hkh Applets Create fd, gSa] muesa ls T;knkrj esa ,d Text Box Object dks gh Applet ij Add fd;k gSA ftl rjg ls geus ,d Text Box dks Applet ij Add fd;k gS] mlh rjg ls ge fofHkUu izdkj ds vU; User Interface Controls dks Hkh Applet ij Display dj ldrs gSaA 193 Any Question or Suggestion, Just Discuss Here...

Java in Hindi fofHkUu izdkj ds User Interface Controls dh Classes dks tkok ds AWT uke ds Package esa Define fd;k x;k gSA blfy, Graphical User Interface Create djus ds fy, gesa vyx ls fdlh vkSj Package dks vius Program esa Import djus dh t:jr ugha gksrh gSA

Abstract Windowing Toolkit pwafd tkok ,d Platform Independent Programming Language gS] tks gesa ,d ls T;knk Platform ij Run gksus okys Applications cukus dh lqfo/kk iznku djrk gS] blhfy, blds Windowing Software dk Hkh Flexible gksuk t:jh FkkA tkok ds Windowing Classes ds Package dk uke Abstract blhfy, j[kk x;k gS] D;ksafd tkok ds bl Package esa mu Classes dk lewg gS] ftuds iz;ksx }kjk ,sls GUI Software cuk, tkrs gS]a tks Platform Independent gksrs gSaA Platform Independent GUI Classes dh t:jr blfy, gksrh gS rkfd cuus okys Software dks World Wide Web ij Execute fd;k tk lds] ftls fofHkUu izdkj ds yksx fofHkUu izdkj ds Computer System o fofHkUu izdkj ds Operating System ij fofHkUu izdkj ds Browsers dk iz;ksx djds Use dj ldsaA

tkok ds bl Toolkit Package esa gesa gj ml pht dh Class izkIr gks tkrh gS] ftldh t:jr fdlh Hkh GUI Program dks Create djus ds fy, iM ldrh gSA tkok ds bl Windowing Toolkit Package dh Classes dk iz;ksx djds ge Buttons, Check Boxes, Labels o vU; Simple Components Create dj ldrs gSaA lkFk gh Text Fields, Dialog Boxes, Pull Down Menus, rFkk vkSj Hkh fofHkUu izdkj ds Components Create dj ldrs gSaA bl Toolkit esa Font, Color o Graphics ls lEcaf/kr Classes Hkh gSa] ftudks geus vius fiNys dqN Applet Programs esa Use Hkh fd;k gSA buds vykok bl Toolkit esa Event Driven Programming ls lEcaf/kr fofHkUu izdkj ds Events dks Handle djus ls lEcaf/kr Classes Hkh gSa] ftudk iz;kssx Program dks Event Driven GUI Program cukus ds fy, fd;k tkrk gSA

Components fdlh Hkh Windowing Programming Language esa gesa”kk Active o Passive nks rjg ds Controls gksrs gSaA Active Controls os Controls gksrs gSa] tks gesa”kk fdlh uk fdlh Event dks Response djrs gSa vkSj fdlh uk fdlh Event Handler dks Trigger djrs gSaA ;fn ljy “kCnksa esa dgsa] rks ge ;s Hkh dg ldrs gSa fd Active Controls gesa”kk fdlh uk fdlh izdkj dk Result ;k Output Generate djrs gSaA tcfd dqN Controls ,sls gksrs gSa] tks Lo;a fdlh izdkj dk Output Generate ugha djrs gSaA ysfdu fofHkUu izdkj ds Active Controls viuk Output iznku dj ldsa] blds fy, mu Active Controls dks viuk dke djus ds fy, txg iznku djrs gSaA bl rjg ds Controls dks Passive Controls ;k Containers dgrs gSaA ;s ,sls Controls gksrs gSa] ftuesa vU; Controls Place fd, tkrs gSaA dqN Controls ,sls Hkh gksrs gSa] tks Active 194 Any Question or Suggestion, Just Discuss Here...

Java in Hindi Control dk dke rks djrs gh gSa] lkFk gh Passive Control ;k Containers dh rjg Hkh dke dj ldrs gSaA Text Box o Check Box ,sls gh nks Active Controls gSa] tks Lo;a rks Active Controls gSa gh] lkFk gh bUgsa fdlh vU; Active Control ds fy, Container dh rjg gh Use fd, tk ldrk gSA

fdlh Hkh Container Control esa ge ftrus pkgsa] mrus Controls dks Place dj ldrs gSaA ;fn ge pkgsa rks Container dks Empty Hkh j[k ldrs gSaA AWT Package esa fofHkUu izdkj ds User Interface Controls dks Components uke dh ,d Class dh fofHkUu Subclasses ds :i esa Define fd;k x;k gSA

;kuh Button Class, Checkbox Class vkfn fofHkUu izdkj ds UI (User Interface) Controls dks Component Class ls Derive fd;k x;k gSA blh Component Class ls Container uke dh ,d Class dks Hkh Derive fd;k x;k gSA bl Container Class dks vkxs fQj ls Panel o Window uke dh nks Subclasses esa Derive fd;k x;k gSA pwafd Panel Class o Window Class nksuksa Classes leku Parent Class Container ls Derived gSa] blfy, bu nksuksa Classes dks Sibling Classes Hkh dgrs gSaA Panel Class ,d ,slk Container gS] ftlds Objects dk iz;ksx vU; izdkj ds Active ;k Passive Objects dks Hold djus ds fy, rks fd;k tkrk gS] ysfdu bl Class ds Objects fn[kkbZ nsus okys User Interface Objects ugha gksrs gSaA bl Panel Class dks vkxs fQj ls Derive djds ftl Class dks Create fd;k x;k gS] ml Class dk uke Applet Class gSA ;s ogh Applet Class gS] ftldks Derive djds geus vHkh rd dbZ Applet Programs Create fd, gSaA Applet Class ds Programs os GUI Programs gksrs gSa] tks Web Pages esa Run gksrs gSaA Panel Class dh Sibling Class ;kuh Window Class ls Hkh Frame o Dialog uke dh nks Subclasses Create dh xbZ gSaA Frame Class ,d ,slh Class gS] ftlds Object ,d fn[kkbZ nsus okys Window ds Frame dks Represent djrs gSaA

;kuh ;fn ge Frame Class dk dksbZ Object Create djrs gSa] rks gesa Screen ij ,d Rectangular Area feyrk gS] ftlesa ,d Title Bar gksrk gS vkSj Frame ds Title Bar ij gh Frame dks Resize djus ds fy, Restore, Minimize, Maximize rFkk Frame Window dks Close djus ds fy, Close Control Buttons feyrs gSaA Frame Class dh rjg gh ge Dialog Class ls Hkh Objects Create dj ldrs gSaA tc ge Dialog Class dk dksbZ Object Create djrs gSa] rc gesa Screen ij ,d Dialog Box feyrk gSA Dialog Box Hkh ,d rjg dk Frame Window gh gksrk gS] ysfdu bl ij Menu Bar ugha gksrk gS] rFkk ge bls Resize ugha dj ldrs gSaA

bl rjg ls gesa Component Class ls rhu rjg ds Containers Applet, Window o Frame izkIr gksrs gSa o Window ls nks vkSj Containers Frame o Dialog Hkh izkIr gksrs gSaA ;kuh ;fn ge lkjka”k ns[ksa rks ge dg ldrs gSa fd tkok esa gesa ikap rjg ds Containers feyrs gSa] ftuesa ls dsoy Panel gh ,d ,slk Container gksrk gS] tks Visually fn[kkbZ ugha nsrk gSA


Java in Hindi Panel Class – The Panel Container ;s ,d cgqr gh egRoiw.kZ Container Class gS] D;ksafd bl Class ds Objects Screen ij Invisible jgrs gSa] ysfdu fdlh Applet Container ;k fdlh Application ds Window ;k Frame Container ij fofHkUu izdkj ds vU; Active ;k Passive Controls dks Organize djus ds fy, bl Class ds Objects egRoiw.kZ Hkwfedk fuHkkrs gSaA Panel Class ds Objects }kjk ge fofHkUu izdkj ds vU; Objects dh Applet ;k Application ds Frame Container ij Location o Size r; dj ldrs gSaA Panel Class dk Object Create djus dk rjhdk Hkh fofHkUu izdkj ds vU; Objects Create djus ds leku gh gSA ;kuh ge fuEukuqlkj Statement }kjk Panel Control Create dj ldrs gSa% Panel newPanel = new Panel();

,d ckj Panel Create djus ds ckn mls Hkh vU; Objects dh rjg gh fdlh Window, Frame ;k Applet ij Add fd;k tkrk gSA Panel dks bu Containers ij Add djus ds fy, gesa Container Class ds add() Method dks Use djuk gksrk gSA ;kuh ;fn ge Applet ds lEca/k esa dgsa rks Applet ds init() Method esa gesa fuEukuqlkj Statement fy[k dj Panel Object newPanel dks Applet esa Add djuk gksrk gS% add(newPanel);

ge ,d Panel ds vUnj nwljk Panel Hkh Nest dj ldrs gSa lkFk gh ge ,d Panel esa ,d ls T;knk Sub – Panels dks Nested dj ldrs gSaA blds vykok ge ,d Nested Panel esa fQj ls ,d ;k vf/kd Sub – Panels dks Nest dj ldrs gSaA ;kuh ge ftrus Level rd pkgsa] mrus Levels rd Panels dh Nesting dj ldrs gSaA mnkgj.k ds fy, fuEu Statements esa geus rhu Levels rd Panels dh Nesting dh gS% Panel mainPanel, subPanel, subSubPanel; mainPanel = new Panel(); subPanel = new Panel(); subSubPanel = new Panel(); mainPanel.add(subPanel); subPanel.add(subSubPanel);

Push Button Control fdlh Hkh GUI Application esa Push Buttons gesa”kk fdlh uk fdlh Event Handler dks Trigger djus dk dke djrk gSA ;kuh Push Button ,d ,slk Component ;k Control gksrk gS] tks fdlh Event Driven GUI Program esa fdlh Event ds Generate gksus ij Event dks Handle djus ds fy, fy[ks x, Event Handler Method dks Execute djus dk dke djrk gSA


Java in Hindi lkekU;r;k lHkh Objects fdlh uk fdlh izdkj ds Event ds Response esa gh dqN uk dqN dke djrs gSa] ysfdu Push Button rks gesa”kk fdlh uk fdlh Event Handler dks Trigger djus dk dke gh djrk gSA vHkh rd geus dsoy TextField dks gh vius Applet ij Add fd;k gSA ftl rjg ls geus TextField Component dks vius Applet ij Add fd;k gS] mlh rjg ls ge fofHkUu izdkj ds vU; Basic User Interface Controls dks Hkh vius Applet ij Add dj ldrs gSaA vU; izdkj ds Components dks vius Applet ij Add djus ds fy, gesa ogh rjhdk Use djuk iMrk gS] ftl rjhds dk iz;ksx djds ,d TextField Component dks Applet ij Place fd;k tkrk gSA ;kuh lcls igys gesa Required Component dh Class dk ,d Object Declare djuk gksrk gSA fQj ml Object dks new Operator dk iz;ksx djds Memory Allocate djuk gksrk gS rFkk Object dks dqN okafNr ekuksa ls Initialize djuk gksrk gS] vkSj vUr esa gesa ml Object dks add() Method dk iz;skx djds Applet ij Place djuk gksrk gSA fuEu Applet Program esa geus nks Text Field Objects o ,d Button Objects dks Applet ij Add fd;k gSA bl Applet Program esa ge ns[k ldrs gSa fd Applet esa Button Add djus ds fy, Hkh geus ogh Process Use fd;k gS] ftl Process dk iz;ksx djds geus ,d TextField Object dks Applet ij Add fd;k gSA Program // File Name: ButtonNTextBoxApplet.java import java.awt.*; import java.applet.*; public class ButtonNTextBoxApplet extends Applet { TextField txtBox1 = new TextField(20); TextField txtBox2 = new TextField(20); Button OKButton = new Button("OK");

}

public void init() { add(txtBox1); add(txtBox2); add(OKButton); }

Output


Java in Hindi

bl Output esa ge ns[k ldrs gSa] fd nksuksa Text Box o Button mlh Øe esa fn[kkbZ ns jgs gSa] ftl Øe esa bUgsa init() Method esa Applet ij Add fd;k x;k gSA Applet esa Button dks Add djus ds fy, geus fuEu Statements dk iz;ksx fd;k gS% Button OKButton = new Button("OK"); add(OKButton);

ge ns[k ldrs gSa fd OKButton Object dks Create djrs le; geus Button Class ds Constructor esa tks String “OK” fy[kk gS] og String Button ds uke ds :i esa gesa fn[kkbZ nsrk gSA bl String dks T;knkrj GUI Programming Languages esa Button dk “Caption” dgk tkrk gSA Program ds Runtime esa ;fn ge fdlh Button ds Caption dks izkIr djuk pkgsa] rks gesa getLabel() Method dk iz;ksx djuk iMrk gSA bl Method dk iz;ksx djus ij ;s Method gesa ml Object ds Label String dks Return djrk gS] ftldk Reference Method esa fn;k x;k gksrk gSA bl Return gksus okyh String dks izkIr djus ds fy, gesa String izdkj dk ,d Object Create djuk gksrk gSA ;kuh ;fn gesa OKButton ds Caption dks izkIr djuk gks] rks gesa fuEukuqlkj Statements fy[kus gksaxs% String captionOfButton; captionOfButton = OKButton.getLabel();

blh rjg ls ;fn gesa Program ds Runtime esa fdlh Push Button ds Caption dks Change djuk pkgsa] rks gesa Button Class ds setLabel() Method dks Use djuk gksrk gS vkSj bl Method esa Argument ds :i esa og String nsuk gksrk gS] ftls ge Caption ds :i esa Push Button ij Display djokuk pkgrs gSaA ;s dke djus ds fy, gesa fuEukuqlkj Statement dk iz;ksx djuk gksrk gS% OKButton.setLabel(“Cancel”); Push Button ds bl Behavior dks ge fuEukuqlkj ,d Applet Program cuk dj Hkh le> ldrs gSa] ftlesa User Push Button ij tc Click djrk gS] rc Push Button dk Caption gj ckj Click djus ij Change gksrk gS% Program // File Name: ButtonCaptionApplet.java import java.awt.*; import java.applet.*; public class ButtonCaptionApplet extends Applet { Button OKButton = new Button(" OK ");


Java in Hindi public void init() { add(OKButton); } public void paint(Graphics g) { String caption = OKButton.getLabel();

}

}

if(caption == " OK ") OKButton.setLabel("Cancel"); else OKButton.setLabel(" OK ");


Output

Label Control vHkh rd geus Applet ij tks Hkh String Display fd;k gS] mls ,d Graphics ds :i esa Display djus ds fy, Graphics Class ds drawString() Method dk iz;ksx djds Display fd;k gSA ysfdu lHkh GUI Languages esa fdlh Static Text dks Window ij Display djus ds fy, gesa”kk ,d fo”ks’k izdkj dk Control gksrk gSA tkok esa bl Static Text Display djus okys Control dks Label dgk tkrk gSA Label Object dk iz;ksx lkekU;r;k User dks Message nsus ds fy, fd;k tkrk gSA ge ;s Hkh dg ldrs gSa fd drawString() Method tks dke djrk gS] ogh dke ,d Label Object djrk gSA Label Object dHkh Hkh dksbZ Action Event Generate ugha djrk gSA Label Object esa fn[kkbZ nsus okys Text dks Program ds Runtime esa izkIr djus ds fy, gesa getText() Method dk iz;ksx djuk iMrk gSA tcfd Program ds Runtime esa Label Object esa fn[kkbZ nsus okys Text dks Change djus ds fy, gesa setText() Method dk iz;ksx djuk iMrk gSA getText() Method ogh dke djrk gS] tks dke Button Object ds fy, getLabel() Method djrk gS vkSj Label Object ds fy, 199 Any Question or Suggestion, Just Discuss Here...

Java in Hindi setText() Method ogh dke djrk gS] tks dke Button Object ds fy, setLabel() Method

djrk gSA

fiNys Program esa gh FkksMk lk ifjorZu djds ge bl Control ds Effect dks Hkh ns[k ldrs gSaA Modified Program fuEukuqlkj gS% Program // File Name: LabelApplet.java import java.awt.*; import java.applet.*; public class LabelApplet extends Applet { Button OKButton = new Button(" OK "); Label lblCaption = new Label(" OK "); public void init() { add(OKButton); } public void paint(Graphics g) { String caption = lblCaption.getText(); OKButton.setLabel(caption);

}

}

if(caption == " OK ") lblCaption.setText("Cancel"); else lblCaption.setText(" OK ");


Output


Java in Hindi ;fn ge bl Applet dks Hkh Run djsa] rks gesa fiNys Program tSlk gh Output izkIr gksrk gSA ysfdu bl ckj Use gksus okys Methods OK Button Class ds ugha gSa] cfYd Label Class ds gSaA vxys Applet Program esa geus rhu Text Boxes, rhu Label Controls o ,d Command Button Object dks Applet ij Place fd;k gSA Applet Program fuEukuqlkj gS% Program // File Name: ThreeControlApplet.java import java.awt.*; import java.applet.*; public class ThreeControlApplet extends Applet { TextField txtBox1 = new TextField(10); TextField txtBox2 = new TextField(10); TextField txtTotal = new TextField(10); Label lblLabel1 = new Label("First Value"); Label lblLabel2 = new Label("Second Value"); Label lblTotal = new Label("Total"); Button OKButton = new Button("Calculate");

}

public void init() { add(lblLabel1); add(txtBox1); add(lblLabel2); add(txtBox2); add(lblTotal); add(txtTotal); add(OKButton); }

Output

fdlh Applet ij fofHkUu Controls dks ftl Øe esa add() Method dk iz;ksx djds Add fd;k tkrk gS] os Controls Applet ij mlh Øe esa Display gksrs gSaA ;kuh ge init() Method esa ftl


Java in Hindi Øe esa fofHkUu Controls dks Applet ij Add djrs gSa] mlh Øe esa os Controls Applet ij fn[kkbZ nsrs gSaA lkFk gh lHkh Controls Applet ds Center esa gh Display gksrs gSaA ;fn fn[kkbZ nsus okys lHkh Controls igyh Line esa Display ugha gks ikrs gSa] rks Lo;a gh Automatically os nwljh Line esa Shift gks tkrs gSaA ;fn ge Applet dks Maximize] Restore ;k Resize djrs gSa] rks fofHkUu Controls dh Position Hkh Change gksrh gSA ;fn ge blh Program ds init() Method esa ifjorZu djds Program dks fuEukuqlkj Modify djsa] rks gesa vxzkuqlkj Applet izkIr gksrk gS% Program // File Name: ModifiedThreeControlApplet.java import java.awt.*; import java.applet.*; public class ModifiedThreeControlApplet extends Applet { TextField txtBox1 = new TextField(10); TextField txtBox2 = new TextField(10); TextField txtTotal = new TextField(10); Label lblLabel1 = new Label("First Value"); Label lblLabel2 = new Label("Second Value"); Label lblTotal = new Label("Total"); Button OKButton = new Button("Calculate"); public void init() { add(lblLabel1); add(lblLabel2); add(lblTotal); add(txtBox1); add(txtBox2); add(txtTotal);

}

}

add(OKButton);

Output


Java in Hindi

;kuh fdlh Hkh tkok Applet ;k Application esa fn[kkbZ nsus okys fofHkUu izdkj ds Visual Components dk Layout gesa gh r; djuk gksrk gSA ;fn ge bl Layout dks Specify ugha djrs gSa] rks tkok Lo;a gh Automatic Layout Set djds fofHkUu Controls dks Applet ij Add djrk gSA tkok ftl Default Layout dk iz;ksx fofHkUu izdkj ds Controls dks Applet ij Place djus ds fy, djrk gS] ml Layout dks Flow Layout dgrs gSaA tkok esa fofHkUu izdkj ds Controls dh Size o Location dks r; djus ds fy, dqN fo”ks’k izdkj dh Classes iznku dh xbZ gSaA bu Classes dk eq[; dke Applet ;k Application ij fn[kkbZ nsus okys fofHkUu izdkj ds dh Location o Size r; djuk gh gksrk gSA tkok dh bu Classes dks Layout Manager Classes dgrs gSaA pwafd tkok ,d Platform Independent Language gS] blfy, blds Programs fofHkUu izdkj ds Hardware o Operating Systems ij Run gksrs gSaA tcfd fofHkUu izdkj ds Hardware o Operating Systems vyx&vyx izdkj ds Coordinate System o Display Device Driver dk iz;ksx djrs gSA bl fLFkfr esa ftl Platform ij dksbZ Application cuk;k tkrk gS] og Application nwljs Platform ij Hkh mlh izdkj dk fn[kkbZ nsxk] ;s fuf”pr ugha gksrk gSA ysfdu pwafd tkok ,d Platform Independent Programming Language gS] blfy, blesa Develop fd, tkus okys Program lHkh Platforms ij leku gh fn[kkbZ nsus pkfg,A tkok esa bl fo”ks’krk dks izkIr djus ds fy, Layout Manager Concept dks Use fd;k x;k gSA Layout Manager Class ds Objects }kjk tc ge dksbZ GUI Program Develop djrs gSa] rks bl Class ds Objects Lo;a gh lHkh Platforms ij Adjust gks tkrs gSa] ftlls gesa lHkh izdkj ds Platforms ij tkok ds Programs leku gh fn[kkbZ nsrs gSaA bl Automatically Adjust gksus okys Programs Develop djus ds fy, gesa Layout Managers dk iz;ksx djuk t:jh gks tkrk gSA

dbZ ckj gesa ,sls Programs cukus gksrs gSa tks fdlh ,d gh Platform ds fy, gksrs gSaA ,sls Programs Adjustable ugha gksrs gSaA ;kuh dbZ ckj gesa ,sls Programs cukus dh t:jr gksrh] ftlds Window ij Placed fofHkUu GUI Objects Window dh Size Change gksus ds ckotwn Hkh viuh Position o Size dks Change ugha djrs gSaA tc gesa ,sls Programs cukus gksrs gSa] rc gesa Layout Managers dks Use djus dh t:jr ugha gksrh gSA ml fLFkfr esa ge fofHkUu izdkj ds Graphical Objects dks Applet ;k Application Window esa mudh Absolute Position ij Place djuk gksrk gSA pwafd fdlh Hkh Applet ;k Frame Window esa gesa”kk Flow Layout uke dk Default Layout Manager Active jgrk gS] blfy, tc gesa Absolute Position ij GUI Objects dks Place djuk gksrk gS] rc gesa bl Layout Manager dks Terminate djuk t:jh gksrk gSA 203 Any Question or Suggestion, Just Discuss Here...

Java in Hindi bls Terminate fd, fcuk ge Absolute Position ij GUI Objects dks Place ugha dj ldrs gSaA bl Default Layout Manager dks Terminate djus ds fy, gesa Applet ds init() Method esa fuEu Statement dk iz;ksx djuk gksrk gS% setLayout(null);

Rectangles and Windows GUI Programming esa Rectangles dk cgqr mi;ksx gksrk gSA yxHkx lHkh GUI Objects dks Represent djus ds fy, Rectangles dk iz;ksx Directly ;k Indirectly gksrk gh gSA Computer esa ge ftrus Hkh Window ns[krs gSa] os lHkh Rectangle Form esa gh gksrs gSaA ;gka rd fd ,d Circle dks Hkh Rectangle Form esa gh Display fd;k tkrk gSA blh rjg ls fdlh GUI Application esa ge ftrus Hkh GUI Objects ns[krs gSa] os lHkh Objects Window gh gksrs gSaA dqN Window ,sls gksrs gSa] tks fdlh nwljs Window dks Contain djus dk dke djrs gSaA ,sls Windows dks Containers dgrs gSa] tcfd dqN Window ,sls gksrs gSa] tks Loa; Active gksrs gSaA Button, Menu Bar Options, Option Buttons, Status Bar, Toolbar vkfn lHkh Windows gh gSa vkSj lHkh Windows Rectangle gh gksrs gSaA

GUI Components – On The Absolute Placement

Layout dks Terminate djus ds ckn gesa gj Object dks mldh Absolute Position ij Place djus dh ftEesnkjh gekjh gksrh gS] D;ksafd ,d ckj Layout dks Terminate dj nsus ds ckn gesa gh Applet dks ;s crkuk iMrk gS fd fdlh GUI Object dks Applet esa fdl Location ij Place djuk gSA

tc rd ge Applet dks Object dh Position ugha crkrs gSa] rc rd Applet ml Object dks Applet esa Draw ugha djrk gSA Applet esa fdlh Object dh Location o Size crkus ds fy, gesa Component Class ds setBounds() Method dk iz;ksx djuk gksrk gSA pwafd lHkh GUI Controls Component Class ls gh Derived gksrs gSa] blfy, ge fdlh Hkh GUI Object dks Resize djus ds fy, ;k Control dh Bounding dks r; djus ds fy, ml Object ds lkFk bl Method dk iz;ksx dj ldrs gSaA bl Method esa gesa Applet ij Place fd, tkus okys Component ds lEca/k esa ogh pkjksa tkudkfj;ka nsuh gksrh gSa] tks ,d Rectangle dks Draw djus ds fy, nsuh gksrh gSaA ;kuh setBounds() Method esa igys nks Arguments Place gksus okys Component ds ( x, y ) Coordinates dks Describe djrk gS] tcfd rhljk Argument Component dh Width rFkk pkSFkk Argument Control dh Height dks Specify djrk gSA void setBounds(int x, int y, int width, int height)

bl Method dk iz;ksx djds ge fuEukuqlkj ModifiedThreeControlApplet.java Program dks Modify djds fofHkUu Controls dks mudh Absolute Position ij Place dj ldrs gSaA bl Program dks Compile djds Run djus ij gesa vxzkuqlkj Output izkIr gksrk gS%


Java in Hindi Program // File Name: ModifiedThreeControlApplet.java import java.awt.*; import java.applet.*; public class ModifiedThreeControlApplet extends Applet { TextField txtBox1 = new TextField(10); TextField txtBox2 = new TextField(10); TextField txtTotal = new TextField(10); Label lblLabel1 = new Label("First Value"); Label lblLabel2 = new Label("Second Value"); Label lblTotal = new Label("Result"); Button btnAdd = new Button("+"); Button btnSub = new Button("-"); Button btnMul = new Button("*"); Button btnDev = new Button("/"); Button btnRem = new Button("%");

}

public void init() { setLayout(null); lblLabel1.setBounds(25, 27, 80, 25); add(lblLabel1); txtBox1.setBounds(150, 27, 215, 25); add(txtBox1); lblLabel2.setBounds(25, 54, 80, 25); add(lblLabel2); txtBox2.setBounds(150, 54, 215, 25); add(txtBox2); lblTotal.setBounds(25, 85, 80, 25); add(lblTotal); txtTotal.setBounds(150, 85, 215, 25); add(txtTotal); btnAdd.setBounds(25, 120, 70, 25); add(btnAdd); btnSub.setBounds(85, 120, 70, 25); add(btnSub); btnMul.setBounds(155, 120, 70, 25); add(btnMul); btnDev.setBounds(225, 120, 70, 25); add(btnDev); btnRem.setBounds(295, 120, 70, 25); add(btnRem); }


Java in Hindi Output

Handling Multiple-Button Events

ButtonCaptionApplet Program esa dsoy ,d gh Button gSA blfy, bl Applet esa tc ge Button ij Click djrs gSa] rc Applet dk action() Method Execute gksrk gSA tc User bl Button ij Click djrk gS] rc tkok Applet Class ds action() Method dks Call djrk gSA

blfy, gesa tks Hkh dke Button ds Click gksus ij djokus gksrs gSa] ml dke ls lEcaf/kr Statements ge action() Method esa fy[k ysrs gSaA ysfdu tc Form ;k Applet ij ,d ls T;knk Button gksrs gSa] rc gesa ;s r; djuk t:jh gks tkrk gS fd Applet ij fLFkr fofHkUu Buttons esa ls dkSulk Button Click fd;k x;k gSA ;s r; djus ds fy, fd Applet ij fLFkr fofHkUu Buttons esa ls dkSulk Button Click fd;k x;k gS] ge Applet Class ds action() Method esa Pass fd, tkus okys nksuksa Arguments dk iz;ksx dj ldrs gSaA public boolean action(Event evnt, Object ObjCaption) Applet Class ds action() Method esa igyk Parameter Event Class dk ,d Object gksrk gS] tcfd nwljk Argument og Object gksrk gS] tks Event Generate djrk gSA nwljs Argument ds :i esa Object dh fdlh fo”ks’krk ;k Property dk iz;ksx djds ge fdlh Event Generator Object dks Uniquely Identify dj ldrs gSa] D;ksafd gj Object dh dksbZ uk dksbZ Value mls Uniquely Identify djus dk ,d ek/;e gksrk gSA

tc Hkh dksbZ Control fdlh uk fdlh izdkj ds Event dks Respond djrk gS] rc tkok ml Event ls lEcaf/kr dksbZ uk dksbZ Object Create djrk gSA ;kuh tc Hkh dksbZ Event Generate gksrk gS] ml Event dks Represent djus ds fy, tkok Event Class dk ,d Object Create djrk gSA Generate gksus okys gj Event Object esa target uke dk ,d Field ;k Attribute gksrk gS] tks ml Object ds Type dks Indicate djrk gS] ftlls Event Generate gqvk gSA ;s irk yxkus ds fy, fd fdl Control Object ls ;k fdl Class ds Object ls Event Generate gqvk gS] ge Event Class ds bl target Field ds eku dks fuEukuqlkj Use dj ldrs gSa%


Java in Hindi if(evnt.target instanceof Button)

;fn Event Generate djus okyk Object evnt Button Class (Abstract Data Type) dk Instance (Object) gksrk gS] rks ;s if Statement True Return djrk gSA Generate gksus okys Event Object ds target Field esa ml Class dh tkudkjh gksrh gS] ftlls Event Generate gqvk gksrk gSA ;kuh ;fn User fdlh Applet ij fLFkr fdlh Button ij Click djrk gS] rks Click djus ij Click Event Generate gksrk gS vkSj bl Event Object ds target Field esa Button Class dh Information Store gksrh gS] tks ;s crkrh gS Button Class ds Instance us bl Event dks Generate fd;k gSA mijksDr Statement ;fn True Return djrk gS] rks ;s bl ckr dk ladsr gS fd Generate gksus okyk Event fdlh Button Class ds Object ls gh Generate gqvk gSA vc ;fn Applet ij ,d ls T;knk Button gksa] rks ;s irk yxkus ds fy, fd dbZ Buttons esa ls Hkh Exactly fdl Button ls Event Generate gqvk gS] ge action() Method ds nwljs Argument ObjCaption dk iz;ksx dj ldrs gSa vkSj Object ds Caption dks fuEukuqlkj Compare djok ldrs gSa% if(ObjCaption == "+")

;fn User us ml Button ij Click fd;k gksxk] ftldk Caption “+” gks] rks ;s Statement True Return djrk gSA bl rjg ls ge fdlh Applet ij ,d ls vf/kd Button esa ls fdl Button ij Click fd;k x;k gS] bl ckr dk irk yxk ldrs gSaA lkFk gh fdl Button ds Click gksus ij D;k gksuk pkfg,] bl ckr dks ge Object ds Event Handler Coding }kjk Specify dj ldrs gSaA bl izfØ;k dks Bhd ls le>us ds fy, ge vius fiNys Program esa gh fuEukuqlkj Modification dj ldrs gSaA Program // File Name: ArithmaticalApplet.java import java.awt.*; import java.applet.*; public class ArithmaticalApplet extends Applet { TextField txtBox1 = new TextField(10); TextField txtBox2 = new TextField(10); TextField txtResult = new TextField(10); Label lblLabel1 = new Label("First Value"); Label lblLabel2 = new Label("Second Value"); Label lblResult = new Label("Result"); Button btnAdd = new Button("+"); Button btnSub = new Button("-"); Button btnMul = new Button("*"); Button btnDev = new Button("/"); Button btnRem = new Button("%");


Java in Hindi public void init() { setLayout(null); lblLabel1.setBounds(25, 27, 80, 25); add(lblLabel1); txtBox1.setBounds(150, 27, 215, 25); add(txtBox1); lblLabel2.setBounds(25, 54, 80, 25); add(lblLabel2); txtBox2.setBounds(150, 54, 215, 25); add(txtBox2); lblResult.setBounds(25, 85, 80, 25); add(lblResult); txtResult.setBounds(150, 85, 215, 25); add(txtResult);

}

btnAdd.setBounds(25, 120, 70, 25); add(btnAdd); btnSub.setBounds(85, 120, 70, 25); add(btnSub); btnMul.setBounds(155, 120, 70, 25); add(btnMul); btnDev.setBounds(225, 120, 70, 25); add(btnDev); btnRem.setBounds(295, 120, 70, 25); add(btnRem);

public boolean action(Event evnt, Object ObjCaption) { if(evnt.target instanceof Button) HandleButton(ObjCaption); }

return true;

protected void HandleButton(Object Caption) { float value1 = 0, value2 = 0, result = 0; String s ; Float toBasicFloat; try {

s = txtBox1.getText();


Java in Hindi toBasicFloat = Float.valueOf(s); value1 = toBasicFloat.floatValue(); s = txtBox2.getText(); toBasicFloat = Float.valueOf(s); value2 = toBasicFloat.floatValue();

} catch(Exception excp) { }

if(Caption == "+") { result = value1 + value2; s = String.valueOf(result); txtResult.setText(s); } else if(Caption == "-") { result = value1 - value2; s = String.valueOf(result); txtResult.setText(s); } else if(Caption == "*") { result = value1 * value2; s = String.valueOf(result); txtResult.setText(s); } else if(Caption == "/") { result = value1 / value2; s = String.valueOf(result); txtResult.setText(s); }

}

}

else { result = value1 % value2; s = String.valueOf(result); txtResult.setText(s); }

Output


Java in Hindi

bl Program esa geus ,d ls T;knk Command Buttons ls Generate gksus okys Events dks Handle djus ds fy, HandleButton uke dk ,d Method cuk;k gSA pwafd ;s Method fdlh Object ds lkFk Call ugha gks jgk gS] cfYd ;s ,d Lora= Method gSA blfy, bl izdkj ds Lora= Method dks tkok esa Function dgk tkrk gSA geus bl Method dks protected Access Specifier ds lkFk Define fd;k gSA protected Access Specifier ;s r; djrk gS] fd ge bl Method dks blh Class esa ;k bl Class dh fdlh Sub Class es Directly Call dj ldrs gSa] ysfdu bl Method dks bl Class ls ckgj Directly Call ugha dj ldrs gSaA


Java in Hindi

Java Object Oriented Programming System


Java in Hindi Java OOPS – Object Oriented Programming Concept

Object Oriented Programming Concept dks le>s fcuk ge Java esa fdlh Hkh rjg dk dksbZ Program ugha cuk ldrs gSaA bruk Basic Concept blfy, Clear fd;k x;k gS] rkfd OOPS o Class dk Concept vklkuh ls Clear gks ldsA Class Java dk lcls t:jh Concept gSA Object Oriented Programming dk Concept le>s fcuk ge dksbZ Serious Program ugha cuk ldrs gSa uk gh bls le>s fcuk Java esa vkxs c< ldrs gSaA

blfy, Class dks le>uk Java dks le>us ds fy, lcls t:jh gSA Object Oriented Concept dks Java ds lkFk Use djrs gq, OOPS dks le>kuk dkQh tfVy dke gSA Object Oriented Technology dk lkj ;gh gS fd Programmers vius Program mlh izdkj ls Design djrs gSa ftl rjg ls Real World esa fdlh dke ;k leL;k dks Design fd;k tkrk

gSA

ge ;gka ij igys ;gh le>saxs fd Object Oriented Design D;k gksrk gS vkSj fdl izdkj ls fdlh leL;k dks Object Oriented Form esa Design djds Computer ij ml leL;k dk lek/kku izkIr fd;k tkrk gSA Object Oriented Programming Concept dk eq[; vk/kkj Object o Class gSaA

Class and Objects

OOPS dk Modal bl rF; ij vk/kkfjr gS fd nqfu;k dh gj og oLrq ftls ge Physically ns[k ldrs gSa] Nw ldrs gSa ;k Logically vuqHko dj ldrs gSa] ,d Real World Object gS vkSj gj Object dbZ vU; NksVs Objects ls cuk gksrk gSA lkFk gh gj Object fdlh uk fdlh Class dk ,d mnkgj.k (Instance) ;k lnL; gksrk gSA ;fn ,d mnkgj.k ns[ksa rks Computer ,d Object gSA ysfdu ;s Computer Lo;a dbZ vU; NksVs Objects tSls fd Motherboard, Processor, RAM, Hard Disk, Floppy Drive, Cabinet, SMPS, Monitor, Keyboard, Mouse vkfn ls feydj cuk gksrk gSA

ge Real World esa Hkh ns[krs gSa fd dbZ Objects ds Features leku gksrs gSaA tSls fd ftrus Hkh Computers gksrs gSa] mu lHkh esa Motherboard gksrk gS] Processor gksrk gS] Hard Disk gksrh gS] RAM gksrh gS] CD ROM gksrk gS] vkfnA ;kuh gj Computer ds Basic Features ;k vk/kkjHkwr vo;o leku gksrs gSaA bu lHkh Objects ds pkfjf=d xq.kksa ;k Characteristics esa le:irk gSA Class ,d ,slk Modal ;k Design ;k Description gksrk gS] ftlds vk/kkj ij leku Characteristics okys dbZ Object Create fd, tk ldrs gSaA ;kuh ;fn nwljs “kCnksa esa dgsa rks Class ,d ,slk Modal, Design ;k Description gksrk gS] tks fdlh ,d veqd (Particular) lewg ds Objects (Entity Set) dh fo”ks’krkvksa (Characteristics) ;k Features dks Represent djrk gSA

tc ge fdlh Object Oriented Programming Language esa Program fy[krs gSa] rks Programming ds le; ge fdlh Object dks Define ugha djrs gSa] cfYd ge ml Object dh fo”ks’krkvksa dk ,d Modal cuk ysrs gSa] ftls Class dgrs gSa vkSj ml Modal (Class) ds vk/kkj ij vko”;drkuqlkj dbZ Objects Create dj ysrs gSaA bls ,d mnkgj.k }kjk le>us dh dksf”k”k djrs gSaA


Java in Hindi ekuyks fd ;fn vkils dgk tk, fd ,d Car dh ifjHkk’kk nhft,A ifjHkk’kk ds :i esa vki D;k dgsaxsA vki Car dh ,slh fo”ks’krkvksa (Characteristics) dk o.kZu (Description) djsaxs tks mls nqfu;k dh nwljh phtksa (Objects) ls vyx cukrh gSA vki dg ldrs gSa fd Car ,d ,slh pht gksrh gS ftlds pkj Wheels gksrs gSaA mlesa cSBus ds fy, dqN lhVsa gksrh gSaA Car esa ,d Engine gksrk gSA ;s Engine Diesel ls pyrk gSA blesa xfr dks izHkkfor djus ds fy, ,d Accelerator vkSj ,d Gear Box gksrk gSA blh rjg ls dbZ vkSj fo”ks’krk,a crkbZ tk ldrh gSa] ftuls ,d Car dh igpku gks ldrh gSA vkius ,d Car dh tks ifjHkk’kk crkbZ gS] D;k og ifjHkk’kk dkj gSA ugha! ;s ifjHkk’kk dkj ugha gS cfYd ;s ifjHkk’kk rks Car dk ,d fooj.k ;k Description ek= gSA ekuyks fd vkidks fdlh Automobile Company ls ;s Offer vkrk gS fd vki ftl rjg dh Car pkgrs gSa] Company ml rjg dh Car cukus ds fy, rS;kj gSA vki ftl rjg dh pkgsaxs] ml rjg dh Car cu tk,xhA vc vkidks Company dks crkuk gS fd vkidks fdl rjg dh Car ilUn gSA lh/kh lh ckr gS fd Company ds Engineers vkidh dYiukvksa okyh Logical Car dks rHkh lkdkj :i dh Physical Car esa cny ldrs gSa] tc vki fdlh rjhds ls mu Engineers dks viuh ml liuksa okyh Logical dkj dk fooj.k ns ik,saA ekuyks fd vki viuh Car esa fuEu fo”ks’krk,a (Characteristics) ;k Features pkgrs gSa% 1 2 3 4

5 6 7 8

vkidh dkj ij Yellow, Blue o White ;s rhu Color gksus pkfg,aA Car gYdh gksuh pkfg,A Car esa dsoy nks lhVsa gh gksuh pkfg,A Car esa lkekU; dkjksa dh rqyuk esa ,d Extra Gear gksuk pkfg, rkfd t:jr iMus ij ml Gear ds iz;ksx ls Car tehu ls Åij Hkh mM ldsA Car dk Engine Latest Quality dk o lcls Highest Power dk gksuk pkfg,A dkj ,slh gksuh pkfg, dh vkidks igpku ldsA tc Hkh vki Car ds ikl tk,a Car vkids fy, njoktk [kksy nsA tc Hkh vki vius xUrO; LFkku ij igqaps] Car ds :drs gh njoktk [kqy tkuk pkfg,A

oxsjg] oxsjgA dYiukvksa dh deh ugha gksrh gS] blfy, ,slh gtkjksa [kwfc;ksa okyh Car dh vki dYiuk dj ldrs gSaA ;s rks vkius viuh liuksa okyh Logical Car dk Description ns fn;kA ysfdu dbZ LFkkuksa ij ,slh t:jr Hkh iM ldrh gS tc vki viuh ckr dks dsoy Description ls ugha le>k ldrsA ml fLFkfr esa vki D;k djsaxsA vki ekusa ;k uk ekus] vki isu vkSj dkxt mBk,axs vkSj Lo;a viuh Car dk ,d iw.kZ lUrqf’Vnk;d Modal ;k Design cuk,axsA D;k ;s Modal vkidh Car gS\ D;k vki bl Modal dks pyk ldrs gS\a ugha! ;s okLrfod dkj ugha gS cfYd ,d Logical Car ;k Car dk Modal ek= gSA ysfdu ;s Modal Qkyrw ugha gS cfYd ;s Modal gh lcls egRoiw.kZ pht gSA ,d ckj bl Modal ds cu tkus ds ckn Company ds Engineers vkidh Logical Car dks ,d Physical Car esa cny ldrs gSa vkSj vkids liuksa okyh Car dks ,d Physical Modal dk :i ns ldrs gSaA ekuyks fd Company ds Engineers us vkidh Car cuk nh vkSj og Car fcYdqy oSlh gh gS tSlh vki pkgrs FksA vc ;fn Company fcYdqy mlh rjg dh ,d vkSj Car cukuk pkgs] rks 213 Any Question or Suggestion, Just Discuss Here...

Java in Hindi D;k Company dks “kq: ls okil lkjk dke djuk iMsxkA D;k mls nqckjk vkils Modal cuokuk iMsxkA ugha! Modal dsoy ,d gh ckj curk gS] ysfdu ml Modal ds vk/kkj ij gtkjksa dkjsa cu ldrh gSa vkSj ftl Modal ds vk/kkj ij gtkjksa Cars cu jgh gSa] ge le> ldrs gSa fd tc rd Modal Change ugha fd;k tk,xk] rc rd cuus okyh lHkh dkjksa dh lHkh [kwfc;ka ,d leku gksaxhA fdlh Hkh Car ds fdlh Hkh Feature ;k Characteristic esa fdlh izdkj dk dksbZ vUrj ugha gksxkA tks Logical Modal vkius cuk;k gS] og Object Oriented Programming Language esa ,d Class dks Represent djrk gS vkSj ml Modal ds vk/kkj ij Company ds Engineers us tks Physical Car cukbZ gS] og Car ,d Physical Object dks Represent djrk gSA ;s Physical Car vkids }kjk cuk, x, Modal (Class) dk ,d mnkgj.k (Instance) ek= gS] D;ksafd ;fn Company pkgs rks mlh Modal ds vk/kkj ij dbZ vU; Cars cuk ldrh gSA ftl rjg ls ,d Modal ds vk/kkj ij ;fn Company pkgs rks gtkjksa dkjsa cuk ldrh gS] mlh rjg ls ,d Object Oriented Programming Language esa ,d ckj ,d Class Design dj ysus ds ckn ,d Programmer ml Class ds ftrus pkgs mrus Instance Create dj ldrk gSA Java esa Class Create djus ds fy, class Keyword dk iz;ksx djuk iMrk gSA okLro esa Class ,d u, izdkj dk User Defined Data Type gksrk gSA ;s ,d ,slk Data Type gksrk gS] ftls Programmer Real World ds Physical Objects dks Computer Software ;k Program ds Logical World ds Object ds :i esa Represent djrk gSA

ge ,d vkSj mnkgj.k ysrs gSaA fiNys mnkgj.k esa geus ,d Modal ds vk/kkj ij Object cuk;k FkkA bl mnkgj.k esa ge ,d Object ds vk/kkj ij Class cuk jgs gSaA ,d Object ds vk/kkj ij ml Object dh Class cukus ds ckn] ml Class ds vk/kkj ij ge ftrus pkgsa mrus Objects cuk ldrs gSa] D;ksafd ,d Object ds Description ds fo”ys’k.k ls gesa Car dk Modal (Class) fey tk,xkA ekuyks fd gesa ,d Physical Car dks Computer esa ,d Logical Car ds :i esa Represent djuk gSA vc Physical dkj dh ,slh D;k fo”ks’krk,a gSa tks mls fdlh nwljs Real World Object ls vyx cukrh gSaA mu Characteristics dks fuEukuqlkj fy[kk tk ldrk gSA ;kuh

1 2 3 4 5 6 7 8 9 10 11 12

,d ,d ,d ,d ,d ,d ,d ,d ,d ,d ,d ,d

Physical Car Physical Car Physical Car Physical Car Physical Car Physical Car Physical Car Physical Car Physical Car Physical Car Physical Car Physical Car

dk dksbZ ,d uke gksrk gSA dk dksbZ uk dksbZ Modal Number gksrk gSA ds Engine dk ,d Unique Serial Number gksrk gSA ds Chassis dk ,d Unique Serial Number gksrk gSA fdlh uk fdlh bZa/ku ls pyrh gSA dk dksbZ Color gksrk gSA dh dksbZ Size gksrh gSA esa dqN Seats gksrh gSaA esa dqN Gear gksrs gSaA dk Pickup Rate gksrk gSA fdlh uk fdlh vf/kdre Speed ij nkSM ldrh gSA esa pkj Wheels gksrs gSaA


Java in Hindi blh rjg ls ge dqN vkSj fo”ks’krk,a Hkh crk ldrs gSa] tks fdlh Car dks ifjHkkf’kr djrh gSaA fdlh ,d Car ds vk/kkj ij ge Car dh bruh fo”ks’krk,a izkIr dj ldrs gSaA bu lHkh Descriptions dks fuEukuqlkj Hkh fy[kk tk ldrk gS% Description of the Car (Class) nameOfCar modalNumberOfCar serialNumberOfEngine serialNumberOfChassis fuelOfCar colorOfCar sizeOfCar noOfSeatsInCar noOfGearsInCar pickupRateOfCar maximumSpeedOfCar noOfWheelsInCar

;fn ge pkgsa rks bu Features esa fuEukuqlkj fofHkUu izdkj ds eku Hkh Fill dj ldrs gSa% Description of the Maruti800 Car (Class) nameOfCar modalNumberOfCar serialNumberOfEngine serialNumberOfChassis fuelOfCar colorOfCar sizeOfCar noOfSeatsInCar noOfGearsInCar pickupRateOfCar maximumSpeedOfCar noOfWheelsInCar

= = = = = = = = = = = =

Maruti800 March1999 12325465 65457898 Diesel Yellow 4.5ft 6 5 60KMPH After 4 Seconds 140KMPH 4

;fn ge FkksMk /;ku nsa rks le> ldrs gSa] fd ;s dqN ,slh Common fo”ks’krk,a ;k dqN ,sls Common Features (Characteristics) gSa] tks yxHkx lHkh izdkj dh dkjksa ds Features dks Represent dj ldrs gSaA mnkgj.k ds fy, geus Åij Maruti800 ds fofHkUu Features ds ekuksa dks ns[kkA vc fuEukuqlkj Features ds ekuksa esa ifjorZu djus ij ge bUgh Features ds vk/kkj ij Tata Indica ;k Tata Sumo dks Hkh Computer esa Logically Represent dj ldrs gSaA ;kuh Description of the Tata Indica Car (Class) nameOfCar =

TataIndica


Java in Hindi modalNumberOfCar serialNumberOfEnginea serialNumberOfChassis fuelOfCar colorOfCar sizeOfCar noOfSeatsInCar noOfGearsInCar pickupRateOfCar maximumSpeedOfCar noOfWheelsInCar

= = = = = = = = = = =

Feb2000 25465454 98787898 Diesel Silver 4.25ft 5 5 80KMPH After 4 Seconds 160KMPH 4

ge ns[k ldrs gSa fd Car ds dsoy ,d Physical Modal ds vk/kkj ij geus Computer esa ,d Logical Modal cuk;k vkSj ml Logical Modal dh Description ds vk/kkj ij ge ftruh pkgsa mruh dkjksa dks Logically Computer esa Represent dj ldrs gSaA bl Description dks gh Class dgrs gSaA bl Car Class ds vk/kkj ij ge ftruh Hkh dkjksa dks Computer esa Logically Represent djsaxs] os lHkh dkjsa blh Car Class ds mnkgj.k (Instance) ;k Objects gksaxs] D;ksafd mu lHkh dkjksa ds Basic Features ,d leku gksaxs dsoy mu Features ds ekuksa esa gh vUrj gksxkA geus ;s Description fdlh ,d Car ds vk/kkj ij Develop fd;k Fkk] ysfdu ;s Description vU; lHkh dkjksa dks Hkh leku izdkj ls Represent dj ldrk gSA Computer esa Hkh ;gh fd;k tkrk gSA fdlh leL;k ds lcls ewy Object dk irk yxk;k tkrk gSA fQj ml ewy Object ds vk/kkj ij leL;k ls lEcaf/kr t:jh Features dks ysdj ,d Description rS;kj fd;k tkrk gSA bl Description ds vk/kkj ij ,d Modal cuk;k tkrk gS vkSj ml Modal ds vk/kkj ij ge ml Class ds ftrus pkgsa mrus Logical Objects Create dj ldrs gSa vkSj mlh rjg ls mUgsa Represent dj ldrs gSa ftl rjg ls Real World Objects dks Represent djrs gSaA ;fn vkils dgk tk, fd ikap dkjksa ds mnkgj.k nks rks vki Tata Sumo, Tata Indica, Maruti Zen, Maruti 1000, o Maruti 800 ds mnkgj.k ns ldrs gSaA D;k bu lHkh izdkj dh dkjksa dks mijksDr Description ds vk/kkj ij Represent ugha fd;k tk ldrk gSA fuf”pr :i ls fd;k tk ldrk gS] D;ksafd ;s lHkh Objects leku Class ds mnkgj.k gSaA ;s lHkh ,d Car Class ds Instances ;k Objects gaS vkSj buds Basic Features leku gSaA ;fn ;gka ge okil ls Class dh ifjHkk’kk dks nksgjk,a rks dg ldrs gSa fd ,d Class leku Featurs okys Objects ds ,d lewg (Entity Set with Similar Features) dk Logical ;k Abstract Representation gksrk gS] tcfd ml Class dk dksbZ Instance (mnkgj.k) ml Class dk Actual Representation ;k Physical Representation gksrk gS ftls Object dgrs gSaA lkekU;r;k tkok dh gj Class nks eq[; Components ls cuh gksrh gS % Attributes mnkgj.k ds fy, fdlh Objects ds ,d lewg (Entity Set) dks yhft,A vki ns[ksaxs fd mu lHkh esa dqN ,slh ckrsa gSa] tks lHkh Objects dks leku :i ls izHkkfor djrh gSaA ;s ogh fo”ks’krk,a gksrh gSa tks fdlh Object dks fdlh nwljs Object ls vyx cukrh gSaA bu fo”ks’krkvksa dks Attributes dgk tkrk gSA 216 Any Question or Suggestion, Just Discuss Here...

Java in Hindi gj Object fdlh uk fdlh Class dk ,d Instance ;k lnL; gksrk gSA fdlh Entity Set ds ;s Attributes gh mudh Class ds Features gksrs gSaA tSls ;fn ge ,d Book dks gh ysa rks Book dh viuh ,d Class gks ldrh gS] ftlls ge nqfu;k dh fdlh Hkh Book dks Describe dj ldrs gSaA vc bl Book dh Class ds Features ogh gksaxs tks fdlh ,d Book ds Features gSaA Book dh ,slh dkSulh Properties gks ldrh gSa] tks ,d Book dks nwljs fdlh Object ls vyx cukrh gSa\ blds loky ds tokc esa ge fdlh Book dks fuEu Properties }kjk ifjHkkf’kr dj ldrs gSa%

1 2 3 4

gj gj gj gj gSA 5 gj 6 gj

Book Book Book Book

dk ,d uke gksrk gSA dk ,d Author gksrk gSA fdlh uk fdlh Publication ls izdkf”kr gksrh gSA dk ,d ISBN Number gksrk gS] ftlls ml Book dh Unique igpku gksrh

Book esa dqN Pages gksrs gSaA Book dh dqN dher gksrh gSA

blh rjg ls Book dh dbZ vkSj Characteristics gks ldrh gSaA ;s lHkh Characteristics ml Book Object dh Class ds Features gksrs gSaA bUgha Features dks Book Class ds Attributes Hkh dg ldrs gSaA ;fn ge bl Book dh Description dks Class ds Modal ds :i esa Describe djsa rks bl Book Object dh Class dks fuEukuqlkj Represent dj ldrs gSa% Book’s Attributes Description (Book Class) bookName bookAuthor bookPublication bookISBN bookPages bookPrice

fdlh Class ds Attributes fdlh Object dh Appearance, State o Condition ds vk/kkj ij r; gksrs gSaA ;kuh fdlh Class dh Description ds Attributes bl rF; ij vk/kkfjr gksrs gSa fd ml Class ds Object fdl izdkj ds fn[kkbZ nsrs gSa vkSj muds Objects dh fLFkfr (Position or Situation) D;k gks ldrh gSA fdlh Object ds bu Appearance o State dh fofHkUu Description gh ml Object dks nqfu;k ds lHkh Object ls vyx igpku iznku djrh gSA mnkgj.k ds fy, bl Book Class dks gh ysrs gSaA ge bl Book Class dk ,d Object Create djds mlds fofHkUu Attributes dks fuEukuqlkj eku iznku dj ldrs gSa& Book’s Attributes Description (Book Class) bookName bookAuthor bookPublication bookISBN bookPages

= = = = =

B with Java in Hindi Kuldeep Mishra Publication 010101010101 600


Java in Hindi bookPrice

=

300

;s lHkh Fields Book dh State ;kuh Situation crk jgs gSaA ;kuh Book dk uke “B with Java in Hindi” gS] tks fd Book dh ,d fLFkfr gSA blh rjg ls Book dh Price 300 gS] ;s Hkh Book dh fLFkfr dks Represent dj jgk gSA ;fn ge Car dk mnkgj.k ysa] rks Car dk Color o Car dh Size Car ds Appearance dks Represent djrk gSA ;kuh ;s crkrk gS fd Car fn[kkbZ dSlh nsrh gSA tcfd Car dk uke State ;k Situation dks Represent djrk gS] tks ;s crkrk gS fd Car dh fLFkfr D;k gS ;kuh Car cukus okyh Company dh Market esa vPNh lk[k gS ;k dksbZ lk/kkj.k Company gSA Class dh Common Descriptions mldh Class ds lHkh Objects ds fy, leku gksrh gSa vkSj Object dh ;s Common Descriptions ,d Object dks nqfu;k ds fdlh Hkh vU; Object ls vyx cukrh gSaA tSls ,d Car vkSj ,d Book nksuksa vyx Object gSaA Car dks Car Class ds Attributes ls igpkuk tkrk gS] tcfd Book dks Book Class ds Attributes lsA Class fdlh Hkh ,d Object ls nwljs Object dks vyx Represent djus dk ,d Description gksrk gS tcfd ,d Object dh mlh Class ds nwljs Objects ls vyx igpku Object ds Features ;k Attributes dks iznku fd, tkus okys eku ij fuHkZj gksrh gSA

;kuh ;fn ,d Book dk uke “B with C In Hindi” gS vkSj nwljh Book dk uke “B with OOPS through C++ In Hindi” gS] rks ;s nksuksa gh Books Book Class dh lnL; gSa] ysfdu nksuksa gh Books vyx Objects dks Represent dj jgh gSa] D;ksafd nksuksa ds bookName Attribute ds eku ;k Data esa vUrj gSA Class ,d Secondary User Defined Data Type gksrk gS] ftls ,d Programmer nqfu;k ds Actual Objects dks Computer esa Logically Represent djus ds fy, Create djrk gSA tc fdlh Object dks Computer esa Logically Represent djus ds fy, Class dh Description ;k Class ds Modal dks rS;kj dj fy;k tkrk gS] rc ml Class dks Computer esa Programming Language ds vuqlkj Define fd;k tkrk gSA Class dks Logically Computer esa Define djus ds ckn ml Class ds Objects Create fd, tk ldrs gSa vkSj muds lkFk mlh izdkj ls dke fd;k tkrk gS] ftl izdkj ls fdlh Real World Object ds lkFk dke fd;k tkrk gSA Java esa ,d Class Create djus ds fy, ge fuEu Syntax dk iz;ksx djrs gSa% Class Defining Syntax class ClassName { //Attributes of the Objects }

//Behaviors of the Objects

Access Specifier o Modifiers ds ckjs esa ge vkxs isaxsA class Java dk ,d Keyword gSA fdlh Class dks Computer esa Create djus ds fy, bl Keyword dk iz;ksx fd;k tkrk gSA bl Keyword ds ckn ,d Programmer dk viuh Class dk uke nsuk gksrk gSA ;s ogh uke gksrk gS ftlds


Java in Hindi vk/kkj ij Programmer vius Program esa ml Class ds Instances ;k Objects Create djrk gSA ;fn ge gekjh Book o Car Class ds lUnHkZ esa ns[ksa rks ;gka gesa Book ;k Car fy[kuk gksrk gSA ;s ,d Identifier gksrk gS blfy, Identifier dks uke nsus ds fy, ftu fu;eksa dk Java esa ikyu djuk gksrk gS] mu fu;eksa dk ikyu ;gka Hkh djuk gksrk gSA ;kuh ge dsoy Small o Capital Letters dk iz;ksx ;k Underscore o $ fpUg dk iz;ksx viuh Class ds uke esa dj ldrs gSaA ;fn gesa vadksa dk iz;ksx djuk gks rks og vad Class ds uke dh “kq:vkr esa ugha vk ldrkA Class dk uke nsus ds fy, Hkh Java esa ,d fu;e dk ikyu fd;k tkrk gSA gkykafd ;fn bl fu;e dk ikyu uk Hkh fd;k tk,] rks Hkh Program ij dksbZ izHkko ugha iMrk ysfdu fQj Hkh bl fu;e dk ikyu djuk pkfg, vkSj bldk fu;e ;s gS fd ftl izdkj ls ,d Variable dk uke gesa”kk Small Letter ls “kq: fd;k tkrk gS mlh rjg ls ,d Class dk uke gesa”kk Capital Letter ls “kq: djuk pkfg,A ;fn uke esa ,d ls vf/kd “kCn gksa] rks gj “kCn dk igyk Character Capital Letter dk gh fy[kuk pkfg,A ge ,d ckj fQj ls Student dk mnkgj.k gh ysrs gSaA ,d Student ds Record dks ge Class ds :i esa Describe dj ldrs gSaA Student dh fofHkUu tkudkfj;ksa ds os Fields ftudh School ds Principal dks t:jr gS os fuEukuqlkj gSa% Student dk uke Student ds firk dk uke Student dk Address Student dh City Student dh rglhy Student dk ftyk Student dk State Student dh Class Student ds Contact Number Student dh Date of Birth Student dh School esa Join djus dh Date of Admission Student dh Age Student dk Serial Number 14 Student dh tkfr

1 2 3 4 5 6 7 8 9 10 11 12 13

;s Description fdlh Hkh Student ds mu Fields dks Represent djrs gSa] ftudh School ds Principal dks t:jr gSA ;fn ge bu Description dks lkekU; Fields esa Convert djsa rks gesa fuEukuqlkj fofHkUu Fields izkIr gksrs gSa] ftudks Combined :i esa ns[kus ij Principal dks fdlh Student ds ckjs esa os lHkh tkudkfj;ka izkIr gks ldrh gSa] ftUgsa ml School dk Principal tkuuk pkgrk gS% 1 2 3 4 5

studentName studentFName studentAddress studentCity studentTehsil


Java in Hindi 6 7 8 9 10 11 12 13

studentDistrict studentState studentClass studentContactNumber studentDateOfBirth studentDateOfAdmission studentAge studentSerialNumber 14 studentCast

pwafd Student ,d Real World Object gS vkSj bls Computer esa Logically Represent djuk gS] blfy, gesa bls Class }kjk Represent djuk gksxkA pwafd Student dh lHkh Basic tkudkfj;ksa ds Fields ftudh School ds Principal dks t:jr gS] gekjs ikl Student Class dh Description ds :i esa miyC/k gS] blfy, ge bUgha Attributes dk iz;ksx Student Class ds fy, dj ldrs gSaA ysfdu blls igys ge fdlh Student ds bu lHkh Fields dks eku iznku djrs gSaA ;s eku fuEukuqlkj iznku fd, tk ldrs gSa% 1 2 3 4 5 6 7 8 9 10 11 12 13

= = = = = = = = = = = = = =

studentName studentFName studentAddress studentCity studentTehsil studentDistrict studentState studentClass studentContactNumber studentDateOfBirth studentDateOfAdmission studentAge studentSerialNumber 14 studentCast

Bal Gopal Nandlal Bedal Road Falna Bali Pali Rajasthan 10th 9352768938 06/03/1982 03/07/1996 15 1234545 Brahmin

ge ns[k ldrs gSa fd ,d Student ds fofHkUu Attributes dks eku ;kuh Data iznku fd;k tk ldrk gSA pwafd ge tkurs gSa fd Computer esa ekuksa dks Store djus ds fy, Variables dk iz;ksx fd;k tkrk gS] blfy, bl Record ds vk/kkj ij ge le> ldrs gSa fd Student ds gj Attribute dks Computer esa Store djus ds fy, gesa ,d Variable dh t:jr gksxhA vc Variable fdl Data Type dk gksxk] ;s ge mijksDr Record esa Fill fd, x, ekuksa ds vk/kkj ij r; dj ldrs gSaA pfy, bl Record ds fofHkUu Attributes dks Class esa Describe djus ds fy, gj Attribute dk Data Type r; djrs gSaA gesa”kk Data Type r; djrs le; gesa lcls igys ;s r; djuk gksrk gS fd fdlh Field dk ;k fdlh Attribute dk eku Numerical gksxk ;k Non-Numerical, ;fn eku Numerical gS] rks gesa ;s ns[kuk gksrk gS fd ml Numerical Field ds lkFk fdlh izdkj dh izfØ;k gks ldrh gS ;k ughaA ;fn izfØ;k gks ldrh gS] rc rks ml Attribute dks mldh Size ds vuqlkj fdlh Numeric Data Type dk Declare djuk pkfg, vU;Fkk ml Numerical fn[kkbZ nsus okys Field ;k


Java in Hindi Attribute dks Hkh String izdkj dk gh Declare djuk pkfg,A pfy,] blh vk/kkj ij ge Student ds fofHkUu Attributers dk Data Type r; djrs gSaA

pwafd Student dk uke] mlds firk dk uke] Address, tkfr] City, District, rglhy] State, Class ;s lHkh ,sls Fields gSa] ftuesa Non-Numerical data Store gksxk] blfy, bu lHkh dks String izdkj ds Data Type dk Declare djuk gksxkA Admission dh Data, Birth Date o Age ;s rhuksa ,sls Fields gSa] ftuds lkFk ;s tkuus ds fy, Processing dh tk ldrh gS] fd dksbZ Student fdrus le; ls School esa gS vkSj fdrus fnu ls School esa gSA ;s tkudkjh izkIr djus ds fy, Current Date dks Admission Date esa ls ?kVk;k tk ldrk gSA lkFk gh ;s rhuksa gh iw.kkZad la[;k,a gSa] blfy, bl izdkj ds Fields dks Integer izdkj dk Declare djuk gksxkA Serial Number, Class o Contact Number ;s rhu Attributes ,sls gSa fd buesa Store rks la[;k gh gksrh gS] ysfdu bu la[;kvksa ds lkFk fdlh izdkj dh Calculation ugha dh tk ldrh gS] blfy, ;fn ge pkgsa rks bUgsa String izdkj ds Variable esa Store dj ldrs gSaA

ysfdu String izdkj dk Variable ,d Character dks Store djus ds fy, 1 Byte ysrk gSA blfy, ;fn 10 vadksa ds Contact Number dks Store djuk gks] rks gesa nl Byte dh Memory blds fy, Reserve djuh gksxh] tcfd ;fn ge Long izdkj dk Variable Declare djrs gSa] rks ge dsoy 8 Bytes esa gh nl vadksa dh la[;k Store dj ldrs gSaA blfy, ;fn ge pkgsa rks bUgsa Long izdkj dk Declare dj ldrs gSaA Class ,d ,slk eku gS] ftlds vf/kdre eku dh Range Byte Data Type dh Range ds vUrxZr vk tkrh gS] blfy, bls Byte izdkj dk Declare djuk Bhd jgsxkA bl izdkj ls ge Students ds lHkh Attributes ds Data Type r; dj ldrs gSaA Data Type r; djus ds ckn bu Data Type ds lkFk gesa bu Attributes dks dsoy Class ds Attributes Section esa fy[kuk gksrk gSA ;kuh ge ,d Student dh Class dks Java Language }kjk fuEukuqlkj Computer esa Logically Describe dj ldrs gSa% Student Class Defining class Student { String studentName; String studentFName; String studentAddress; String studentCity; String studentTehsil; String studentDistrict; String studentState; byte studentClass; long studentContactNumber; long studentDateOfBirth; long studentDateOfAdmission; byte studentAge; String studentSerialNumber; String studentCast; //Behaviors of the Objects }


Java in Hindi pwafd fdlh Class ds Create gksus okys lHkh Instances ,d vyx Object gksrs gSa vkSj muds Attributes ds eku Hkh vyx&vyx gksrs gSaA tSls Govind uke ds fdlh Student ds Record o Shyam uke ds fdlh Student ds Record, bu nksuksa Objects ds Record ds gj Field ;k Attribute dk eku vyx gksxkA ;s vyx eku Memory esa rHkh Store gks ldrs gSa] tc gj Object ds bu Attributes ds fy, Memory esa vyx Space gksA okLro esa gksrk Hkh ,slk gh gSA tSlkfd geus igys Hkh dgk fd Class rks ek= fdlh Object ds Attributes dh ,d Description ek= gksrh gSA ml Description ds vuqlkj ftrus Hkh Objects curs gSa] mu lHkh Objects ds gj Attribute dks Store gksus ds fy, ,d vyx Variable feyrk gSA pwafd gj Object fdlh Class dk ,d Instance gksrk gSA blfy, gj Object ds bu Attributes dks Represent djus okys Variables dks Hkh Instance Variable dgrs gSaA blh mnkgj.k ds vk/kkj ij ge Car o Book dh Class dks Hkh Create dj ldrs gSaA Class ,d izdkj dk u;k Data Type gksrk gS ftls Programmer fdlh Real World Object dks Computer esa Logically Represent djus ds fy, Develop djrk gSA Class ,d ,slh Specification gksrh gS] ftlesa fdlh Object ls Related Attributes dks ,d Group ds :i esa Specify fd;k tkrk gS vkSj ml Object ds lHkh Attributes dks ,d lkFk Access fd;k tk ldrk gSA

mnkgj.k ds fy, Book Class ,d Real World Book Object dks Represent djrk gS] ftlesa Book ls lEcaf/kr Related Attributes ds Data Store fd, tk ldrs gSaA geus fiNys v/;k;ksa ls ;s le>k gS fd ;fn gesa fdlh ,d Numerical ;k Non-Numerical Data dks Computer esa Store djuk gks] rks ge ,d Variable Declare djrs gSaA blh rjg ls tc gesa ,d gh izdkj ds dbZ Data dks Computer esa Store o Access djuk gks] rks ge Array dk iz;ksx djrs gSaA ysfdu tc gesa fofHkUu izdkj ds Data Type ds ekuksa dks Computer esa Store djds Manage djuk gksrk gS] rc gesa ml Object dh lHkh Related Fields dks ,d Group esa j[k dj Manage djus dh t:jr gksrh gSA bl t:jr dks iwjk djus ds fy, ge Java esa Class Create djrs gSaA mnkgj.k ds fy, ekuyks fd gesa fdlh Box Object dks Computer esa Represent djuk gSA fdlh Box ds fuEukuqlkj rhu Attributes gks ldrs gSa] ftUgsa ,d Group Data ds :i esa Computer dh Memory esa Store o Manage fd;k tk ldrk gS%  Box dh Height  Box dh Width  Box dh Length

;fn ge bu rhuksa Attributes ds vk/kkj ij ,d Class Develop djuk pkgsa] rks fuEukuqlkj dj ldrs gSa% public class Box { double height; double width; double length; }


Java in Hindi tSlkfd geus igys dgk fd Class ,d u, izdkj dk Data Type gksrk gS] tks fdlh Real World Object dks Computer esa Logically Represent djrk gSA blfy, gekjh Box Class Hkh ,d u, izdkj dk Data Type gS vkSj ge blds Instance ;k uh Object Create djds vius Program esa mlh rjg ls Use o Access dj ldrs gSa] ftl rjg ls fdlh Basic Data Type ds Variable dks djrs gSaA nksuksa ds mPpkj.k esa vUrj dsoy bruk gS fd Basic Data Type ds Instance dks Variable dgrs gSa vkSj Class izdkj ds Data Type ds Instance dks Object dgrs gSaA lkFk gh pwafd Basic izdkj dk Data Type fdlh le; esa dsoy ,d gh eku dks Hold djrk gS tcfd Class izdkj dk Data Type ,d le; esa ,d ls vf/kd Basic Data Type ds ekuksa dks Hold dj ldrk gSA ;fn gesa gekjs Program esa Box Class dk dksbZ Object Create djuk gks] rks ge ;s dke fuEukuqlkj Statement }kjk djrs gSa% Box cpuCabineta = new Box();

pwafd Class Specification dsoy ,d Template ek= gksrk gS] blfy, dksbZ Class Lo;a rc rd Memory esa dksbZ Space reserve ugha djrk gS tc rd fd ml Class dk dksbZ Instance ;kuh Object Create uk fd;k tk,A tc mijksDr Statement Execute gksrk gS] rHkh Box Class dk Object cpuCabinet Memory esa Space Reserve djrk gSA ge fdlh Class ds ftrus Hkh Instance Create djrs gSa ml gj Object ds Data dh Lo;a dh height, width o length Copy gksrh gS] ftlesa ml Particular Object ds Data dks Store fd;k tk ldrk gSA bu Instance Variables dks Access djus ds fy, gesa Java esa Dot Operator dk iz;ksx djuk gksrk gSA ;s Operator Object ds uke dks Object ds Instance Variable ls Link djus dk dke djrk gSA mnkgj.k ds fy, ekuyks fd fdlh CPU dh Length 100 CM, Width 20CM o Height 70 CM gSA ;fn ge bu rhuksa ekuksa dks cpuCabinet Object esa Store djuk pkgsa rks fuEukuqlkj dj ldrs gSa%

cpuCabinet.length = 100; cpuCabinet.height = 70; cpuCabinet.width = 20;

ekuyks fd gesa cpuCabinet dk vk;ru (Volume) Kkr djus ds fy, Program fy[kuk gSA ;s Program ge fuEukuqlkj fy[k ldrs gSa% Program class Box { double width; double height; double length; } public class BoxDemo


Java in Hindi {

public static void main(String args[]) { Box cpuCabinet = new Box(); double volume; cpuCabinet.length = 100; cpuCabinet.height = 70; cpuCabinet.width = 20; volume = cpuCabinet.length * cpuCabinet.height * cpuCabinet.width;

}

}

System.out.println("Volume is " + volume);

Output Volume is 140000.0

tSlkfd geus igys Hkh dgk fd ftl Class esa main() Method gksrk gS] ogh Class lcls igys Compiler gksrh gSA blfy, ;s t:jh ugha gksrk gS fd ftl File esa main() Method okyh Class gks mlh File esa main() Method }kjk Use dh tk jgh lHkh Classes dk Declaration o Definition gksA ge fofHkUu izdkj dh Classes dh vyx QkbZy cuk ldrs gSa vkSj mu Class Files dks ,d Package esa Include djds ml Package dks viuh Source File esa import Statement }kjk Call dj ldrs gSaA bl lEca/k esa ge vkxs ppkZ djsaxsA

Declaring Objects tSlkfd igys Hkh crk;k gS fd Class Specification ,d izdkj dk u;k Data Type gksrk gS vkSj ge bl Type dk iz;ksx Objects Create djus ds fy, djrs gSaA ysfdu fdlh Class ds Object dks Create djus esa nks Steps Use gksrs gSaA igys Step esa ge Class Type ds Object dks Declare djrs gSaA Class izdkj dk ;s Variable Object dks Define ugha djrk gS cfYd ;s ,d lk/kkj.k Variable dh rjg gksrk gS] tks ml Class ds fdlh Object dks Refer dj ldrk gSA nwljs Step esa gesa Object dh Actual Copy izkIr djuh gksrh gS vkSj bl Actual Copy dk Address izFke Step esa Create gksus okys Variable dks iznku fd;k tkrk gSA ;s dke ge new Operator dks Use djds djrs gSaA new Operator Dynamically Run Time esa Object dks Memory Allocate djrk gS vkSj ml Allocated Memory Block dk Reference Return djrk gSA ;s Reference ml Actual Memory Block dk Address gksrk gS tks fd Class izdkj ds ml Variable dks iznku fd;k tkrk gSA Java esa Class izdkj dk gj Object Dynamically Create gksrk gSA fdlh Object dks Dynamically Create djus ds fy, ge fuEukuqlkj Syntax dk iz;ksx djrs gSa% Box cpuCabinet = new Box();


Java in Hindi bl ,d Statement esa fuEukuqlkj nks Statements Combined gSa& Box cpuCabinet; cpuCabinet = new Box();

// Declaration of Reference to Object // Allocate a Box Object

igyk Statement Box izdkj ds Object dk Reference Store djus ds fy, cpuCabinet uke dk ,d Object Create djrk gSA bl Statement }kjk Create gksus okys Statement esa rc rd null Initialized jgrk gS] tc rd fd nwljk Statement Execute ugha gks tkrkA ;kuh igys Statement ds Execution rd bl Object esa fdlh izdkj dh Memory Block dk Address blesa Stored ugha gS vkSj bl Object }kjk ge fdlh izdkj ds eku dks Memory esa Store ugha dj ldrs gSaA ;fn ge bl le; rd bl Object dks Use djuk pkgsa rks ,d Run Time Error Generate gksrk gSA tc nwljk Statement Execute gks tkrk gS] rc ge cpuCabinet dks ,d Box dks Represent djus okys Object dh rjg Use dj ldrs gSaA ysfdu okLro esa cpuCabinet Object esa Actual Box Object ds Memory Block dk Address gh Stored jgrk gSA bu nksuksa Statement ds Effect dks ge fuEukuqlkj iznf”kZr dj ldrs gSa&

new Operator – A Closer Look tSlkfd igys crk;k fd new Operator fuEukuqlkj Statement }kjk Dynamically Memory Allocate djus dk dke djrk gS% Class_Variable [Object] = new ClassName( );

bl Statement esa Class_Variable og Object gS ftlds fy, Memory Allocate gks jgh gS vkSj ClassName() og Class gS ftlds Object dks Memory Allocate dh tk jgh gSA ClassName ds ckn Parenthesis dk iz;ksx gksus ij bls Constructor dgrs gSaA Constructor gj Class dk ,d egRoiw.kZ fgLlk gksrk gS ftldh ftruh Hkh Classes Specify djrs gSa mu lHkh esa Constructor dks ge ,slk ugha djrs gSa rks Java Lo;a ,d Constructor miyC/k Constructor dgrs gSaA geus Box Class esa dksbZ Constructor

dbZ fo”ks’krk,a gksrh gSaA ge t:j Define djrs gSaA ;fn djokrk gS] ftls Default Create ugha fd;k gSA bl


Java in Hindi fLFkfr esa Java Lo;a gesa ,d Constructor miyC/k djokrk gS] ftldk iz;ksx ge Box Class ds Object Create djus ds fy, dj ldrs gSa] tSlkfd fiNys mnkgj.k esa geus fd;k gSA geus igys dgk fd Class ,d u, izdkj dk Data Type gksrk gS tks Programmer viuh lqfo/kkuqlkj fdlh Real World Object dks Computer esa Logically Represent djus ds fy, Create djrk gSA bl fLFkfr esa ge lksap ldrs gSa fd ftl rjg ls ge Integer ;k float izdkj ds Variables Create djrs gSa] mlh rjg ls Class izdkj ds Objects Create D;ksa ugha dj ldrs gSaA bldk tokc ;s gS fd ge Basic izdkj ds Data Type ds Variables dks Objects dh rjg Implement ugha dj ldrs gSaA cfYd ;s lkekU; Variable dh rjg Implement fd, tkrs gSaA ,slk Program dks Efficient cuk, j[kus ds fy, fd;k tkrk gSA ge le> ldrs gSa fd Class izdkj ds Object esa ,d ls T;knk izdkj ds eku Store fd, tk ldrs gSaA blfy, fdlh Object dks lkekU; Variable dh rjg Use ugha fd;k tk ldrkA new Operator Program ds Run Time esa Object dks Memory Allocate djrk gSA bldk Qk;nk ;s gksrk gS fd Program ds Run Time esa ;fn vf/kd Objects dh t:jr gks rks vf/kd Object Create fd, tk ldrs gSa vkSj ;fn de Object dh t:jr gks rks ge viuh vko”;drkuqlkj de Object Hkh Create dj ldrs gSaA

pwafd Primary Memory dh ek=k lhfer gksrh gS] blfy, ;fn vf/kd Object Create gksrs gSa rks ,d Run Time Error (Exception) Generate gksrh gSA ge bl iqLrd esa ftrus Hkh Program ns[ksaxs] mu lHkh Programs esa ,slh dksbZ Problem ugha vk,xhA ysfdu tc Real World ds cMs Project cuk, tkrs gSa] rc Efficiency izkIr djus ds fy, bl izdkj ds Exception dks igys ls gh Handle djus ds Procedures fy[kus t:jh gksrh gSaA

Object Reference

Object Reference Variable ml rjg ls dke ugha djrk gS ftl rjg ls ge lksprs gSaA mnkgj.k ds fy, fuEu Code Fragment nsf[k,& Box cpuCabinet = new Box(); Box hardDiskDrive = cpuCabinet;

bl Statement ls nks Object Create ugha gksrs gSa tks Memory esa Actual Memory Occupy djsaA okLro esa bl izdkj ds Statement ls dsoy ,d gh Object Create gksrk gS] tks Actual Memory Reserve djrk gS vkSj cpuCabinet o hardDiskDrive nksuksa gh Object Variables mlh leku Actual Memory Object dks Refer djrs gSaA ;fn ge fuEu Statement }kjk Object cpuCabinet dks null Assign djsa% cpuCabinet = null;

rks cpuCabinet Object dks tks Actual Memory new Operator }kjk Allocate gqbZ Fkh] og Release ugha gksrh gSA cfYd hardDiskDrive vHkh Hkh ml Actual Memory dks Refer dj jgk gksrk gSA bls ge vxzkuqlkj fp= }kjk le> ldrs gSaA


Java in Hindi

cpuCabinet o hardDiskDrive nksuksa gh Objects Actual Physical Memory Object ds dsoy Reference ek= gSaA okLro esa os Lo;a Objects ugha gSaA buesa dsoy okLrfod Physical Memory Object dk Address ek= gksrk gSA

blfy, ;fn ge cpuCabinet Object esa null Assign dj nsrs gSa] rks ge okLro esa dsoy bl Object ls Actual Memory Object dks Refer djus okys Address dks Destroy dj jgs gksrs gSaA okLrfod Physical Memory rc rd Release ugha gksrh gS] tc rd fd dksbZ Hkh vU; Class Variable ml Memory Block dks Refer dj jgk gksrkA gekjs bl Code Segment esa ftl Memory Block dks cpuCabinet Class Variable Refer dj jgk gS mlh Memory Block dks hardDiskDrive Class Variable Hkh Refer dj jgk gSA blfy, ;fn cpuCabinet Object dks null Assign fd;k tk,] rks Hkh ;s Object Destroy ugha gksxkA geus Class rks cuk yh vkSj mnkgj.kksa }kjk mls Access djuk Hkh lh[k fy;k] ysfdu ;s Class vHkh iwjh ugha gSA ftl rjg ls gj Object dh dqN States ;k Situations gksrh gSa] ftuls og vU; Objects ls vyx igpku izkIr djrk gSA blds vykok gj Object fdlh uk fdlh izdkj dk O;ogkj Hkh djrk gSA ;kuh gj Object esa O;ogkj djus dh Hkh dqN (Abilities) {kerk,a gksrh gSaA tSls ,d i{kh Class ds Instances dks ns[ksa rks gj i{kh ds ikl ia[k gksrs gSa] gj i{kh ds pksap gksrh gSA ;s nksuksa Features rks ;s crkrs gSa fd dksbZ i{kh fdl rjg dk fn[krk (Appearance) gSA blds vykok ,d i{kh dqN dke Hkh dj ldrk gSA ;kuh og nkuk [kk ldrk gS vkSj mM Hkh ldrk gSA ;kuh gj Object dh viuh dqN fLFkfr;ka (States) gksrh gSa vkSj gj Object dh viuh dqN {kerk,a (Abilities) gksrh gSaA Object dh mu {kerkvksa ls Object dh States esa ifjorZu gksrk gSA fdlh Hkh Object dh fLFkfr (State and Appearance) ds eku esa ifjorZu gks ldrk gSA ;kuh ;fn dkj dk gh mnkgj.k ysa rks dksbZ Car Yellow Color dh Hkh gks ldrh gS vkSj fdlh nwljh Car dk Color Blue Hkh gks ldrk gSA ge fdlh Car ds Color dks Red Color ls Hkh Paint dj ldrs gSa vkSj White Color ls Hkh Paint dj ldrs gSaA ;kuh Real World esa fdlh Hkh Object dh fLFkfr esa ifjorZu fd;k tk ldrk gSA mlh izdkj ls Computer esa Hkh fdlh Object ds Color State ;k Attribute dk eku Change fd;k tk ldrk gSA ;kuh ge ;s Hkh dg ldrs gSa fd Real World esa ,d Object esa mlds Attributes ds eku dks Change djus dh {kerk gksrh gSA


Java in Hindi ,d Real World Object ftl Operation dks Perform djds viuh fLFkfr ;k Appearance esa ifjorZu djrk gS] ml Operation dks Operation dk Behavior ;k Object dh Ability dgrs gSaA pfy,] ,d vkSj mnkgj.k ns[krs gSaA ge lHkh us ns[kk gS fd cMs “kgjksa esa dbZ&dbZ eaftyksa dh bekjrsa gksrh gSa blfy, vDlj mu eaftyksa ij igqapus ds fy, Lift dk iz;ksx fd;k tkrk gSA Lift dks lkekU;r;k Elevator dgrs gSaA Elevator Hkh ,d Real World Physical Object gS] D;ksafd ge bls ns[k vkSj Nw ldrs gSaA ;fn ge bldh States o Appearance ;kuh Characteristics dks Describe djsa rks bl Elevator dk fuEukuqlkj Description ns ldrs gSa% 1 ,d Elevator fdlh uk fdlh eafty (Floor) ij :dk gqvk ;k fLFkr gks ldrk gSA 2 ,d Elevator vf/kdre pkj yksxksa dks ogu ldrk gSA 3 ,d Elevator esa dqN Buttons gksrs gSa] ftudks Press djds fofHkUu Passengers fdlh uk fdlh Floor ij igqap ldrs gSaA 4 ,d Elevator esa ,d njoktk gks ldrk gS tks Open o Close gksrk gSA fdlh Elevator esa ;s rhuksa xq.k gks ldrs gSa tks ml Elevator dh fLFkfr o Appearance dks Describe dj jgs gSaA ysfdu ;s Elevator Passengers dh bPNkuqlkj dqN Operations Hkh Perform dj ldrk gS] D;ksafd bu Operations dks Perform djus dh Ability Hkh ,d Elevator Object esa gksrh gSA Elevator dh bu Abilities dks fuEukuqlkj Describe fd;k tk ldrk gS% 1 ,d Elevator fdlh Hkh le; fdlh uk fdlh Floor ij fLFkr gksxk] blfy, og viuh Current State esa ifjorZu djus ds fy, viuh eafty (Floor) ls Åij dh eafty (Floor) ij tk ldrk gSA 2 ,d Elevator fdlh Hkh le; fdlh uk fdlh Floor ij fLFkr gksxk] blfy, og viuh Current State esa ifjorZu djus ds fy, viuh eafty (Floor) ls uhps dh eafty (Floor) ij vk ldrk gSA 3 Passengers Elevator esa izos”k dj ldsa vkSj Elevator ls ckgj fudy ldsa] blds fy, ,d Elevator dk njoktk (Door) Open ;k Close gks ldrk gSA 4 tc dksbZ Passenger fdlh eafty ij tkus ds fy, ml eafty dk dksbZ Number Press djrk gS] rc Elevator ;s Calculate dj ldrk gS fd mls fdl txg tkuk gSA 5 ,d Elevator ;s Hkh irk yxkrk gS fd ml Building ds vU; Elevators fdl fLFkfr (Floor) ij gSaA bl Elevator Object dh States ;k Characteristics o Object }kjk mu Characteristics ij Perform fd, tk ldus okys Operations dks ge fuEukuqlkj Describe dj ldrs gSa& //Characteristics (Attributes or States) noOfCarrentFloor noOfPassengers listOfButtonsPushed //Performable Operations (Behaviors or Abilities) GoDown GoUp OpenDoors CloseDoors


Java in Hindi GetOtherElevatorsInfo CalculateWhereToGoNext

bl mnkgj.k ls ge le> ldrs gSa fd ,d Real World Physical Object esa Hkh okLro esa nks Components gksrs gSaA igyk Component Object dh fLFkfr crkrk gS vkSj nwljk Component Object dh {kerk crkrk gSA tc ,d Real World Physical Object ds Hkh nks Component gksrs gSa rks ml Object dks Represent djus okyh Logical Class esa Hkh bu nksuksa Components dk Description gksuk pkfg,] rkfd Computer dk Logical Object Real World ds Physical Object dks iwjh rjg ls Represent djsA ,d vkSj mnkgj.k ysrs gSa] Real World ds Class o Objects dh ifjHkk’kk ds vuqlkj nqfu;k dh gj pht dks mldh Class cuk dj] ml Class ds Instance ;kuh Object ds :i esa ifjHkkf’kr fd;k tk ldrk gSaA blh vk/kkj ij vki Hkh ,d Real World Physical Object gSa vkSj fdlh ,d le; ij vki Hkh fdlh uk fdlh ,d Class ds Instance gksrs gSaA mnkgj.k ds fy, eku yhft, fd vki ,d Student gSa vkSj 10th d{kk esa i

Java in Hindi 1 2 3 4 5 6 7 8 9 10 11

Student Entity Set Student Entity Set Student Entity Set Student Entity Set Student Entity Set Student Entity Set Student Entity Set Student Entity Set Student Entity Set Student Entity Set Student Entity Set 12 Student Entity Set

ds ds ds ds ds ds ds ds ds ds ds ds

gj gj gj gj gj gj gj gj gj gj gj gj

Entity Entity Entity Entity Entity Entity Entity Entity Entity Entity Entity Entity

dk ,d Serial Number gksrk gSA dk ,d uke gksrk gSA ds firk dk uke gksrk gSA dk ,d Address gksrk gSA dh ,d City gksrh gSA dh ,d District gksrh gSA dk ,d State gksrk gSA ds City dk ,d Pin Code Number gksrk gSA dh dksbZ tkfr gksrh gSA dk dksbZ jax gksrk gSA dh dksbZ d{kk gksrh gSA ds dn dh ,d yEckbZ gksrh gSA vkfn

blh rjg ls ge ,d Student dh dbZ vkSj Attributes o States dk irk yxk ldrs gSaA pfy,] Real World esa ge ns[krs gSa fd gj Object viuk dke [kqn djrk gSA ekuyks fd vki ,d Student gSaA D;k vkidks Hkw[k yxus ij vkidk [kkuk dksbZ vkSj [kk ldrk gSA D;k vkidks I;kl yxus ij vkids fy, dksbZ vkSj ikuh ih ldrk gSA D;k ,slk gksrk gS fd School tkrs le; vkidh Uniform dksbZ vkSj igus vkSj School vki pys tk,aA D;k ,slk gksrk gS fd vkids cnys dksbZ vkSj vkidk Exam Fight djs vkSj feyus okyk Certificate vkids uke dk gks vkSj vki dks izkIr gks tk,A ugha! Real World esa ,slk ugha gksrkA blhfy, Computer esa Hkh ;fn ,slk gksrk gS] rks ml Programming Language dks Object Oriented ugha dgk tk ldrkA Java esa Hkh ,slk ugha gksrk gSA fdlh Class ds Description ds vk/kkj ij tks Object Create fd;k tkrk gS] ml gj Object dk viuk Lo;a dk Attribute ;k States dks Represent djus okyk Lora= Variable gksrk gS] ftlesa dsoy mlh Object ds Attributes ;k States ds eku gksrs gSaA pfy,] vc Object ds Behavior ;k Ability ij FkksMk vkSj fopkj djrs gSaA ge lHkh bUlku gSaA gekjh ,d Physical vkd`fr] jax] :i] yEckbZ vkfn gS] blfy, ge lHkh Human Being Class ds Instances ;k Objects gSaA ;fn ge ,d Human Being Class dk Description nsuk pkgsa] rks fuEu Description ns ldrs gSa& 1 2 3 4 5 6 7 8 9 10

gj gj gj gj gj gj gj gj gj gj

Human Being Human Being Human Being Human Being Human Being Human Being Human Being Human Being Human Being Human Being

dk ,d uke gksrk gSA

Object ds ikl mldk Lo;a dk fnekx gksrk gSA

ds nks gkFk gksrs gSaA ds nks iSj gksrs gSaA ds ,d flj gksrk gSA ds flj ij cky gksrs gSaA dku gksrs gSa ds nks vka[ksa gksrh gSaA ds psgjs ij ,d eqag gksrk gSA ds nksuksa gkFkksa esa ikap vaxqfy;ka gksrh gSaA vkfn

bu lHkh States o Attributes ds vykok ,d Human Being esa dqN Abilities Hkh gksrh gSaA dqN Abilities dks fuEukuqlkj Describe fd;k tk ldrk gS& 1 gj Human Being viuk uke Change dj ldrk gSA a rk gS vkSj fu.kZ; ysrk gSA 2 gj Human Being Object vius fnekx ls lksp 3 gj Human Being vius gkFkksa dk iz;ksx djds fdlh izdkj dk b”kkjk dj ldrk gSA 230 Any Question or Suggestion, Just Discuss Here...

Java in Hindi 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18

gj gj gj gj gj gj gj gj gj gj gj gj gj gj gj

Human Being Human Being Human Being Human Being Human Being Human Being Human Being Human Being Human Being Human Being Human Being Human Being Human Being Human Being Human Being

vius iSjksa ls py ldrk gSA Hkkx ldrk gSA vius flj ij Vksih j[k ldrk gSA vius flj ij ixMh cka/k ldrk gSA vius flj ds fc[kjs gq, ckyksa dks da?ks ls laokj ldrk gSA vius cky dVok ldrk gSA vius cky cMs dj ldrk gSA vius dkuksa ls lqu ldrk gSA viuh vka[kksa ls ns[k ldrk gSA viuh vka[kksa dks cUn djds lks ldrk gSA viuh vka[kksa ls b”kkjs dj ldrk gSA vius eqag ls cksy ldrk gSA vius eqag ls [kkuk [kk ldrk gSA vius gkFkksa dh vaxqfy;ksa esa dksbZ pht idM ldrk gSA vius gkFkksa dh vaxqfy;ksa ls dksbZ pht Qsad ldrk gSA

;gka geus dqN ,sls dke crk, tks lHkh Human Being Class ds Instances ;kuh bUlku Objects dj ldrs gSaA ,sls vkSj Hkh gtkjksa mnkgj.k fn, tk ldrs gSaA D;k vkidks Human Being Object ds States o Behavior esa fdlh izdkj dk dksbZ lEca/k irk pyk \ gj Object ds Attributes o Objects ds Operations esa ,d lEca/k gksrk gS vkSj lEca/k cl ;gh gS fd ,d Object dqN Operations Perform djds vius gh fdlh Attribute dh State dks Change djrk gSA ge bl Human Being mnkgj.k dks gh ysa] rks gj Human Being Object ds cky gksrs gSa vkSj gj Human Being Object fdlh izdkj dk Operation Perform djds vius ckyksa dh fLFkfr esa ifjorZu dj ldrk gSA ckyksa dh fLFkfr esa ifjorZu djuk Object dh ,d Ability gSA blh rjg ls gj Human Being Object ds iSj gksrs gSaA ;s iSj Human Being Object dk Attribute gSA bl Attribute dh State dks Change djus ds fy, Object ml ij pyus dk Operation Perform dj ldrk gSA Object ds pyus ls Object ds iSj dh fLFkfr (State) esa ifjorZu gksrk gSA gj Human Being Object ds ikl viuk eqag gksrk gS tks fd Human Being Object dk ,d Attribute gSA ;fn Human Being [kkuk [kkrk gS] rks mldk eqag pyrk gS ;kuh eqag dh fLFkfr (State) esa ifjorZu gksrk gSA ;kuh ;fn ge lkjka”k esa dgsa rks dg ldrs gSa fd gj Object esa fdlh Hkh izdkj dk Operation Perform djds vius Lo;a ds Attributes dh fLFkfr (States) esa ifjorZu djus dh {kerk (Ability) gksrh gSA ,d Object dsoy Lo;a gh vius Attributes dh fLFkfr (State) esa ifjorZu djus ds fy,] fdlh izdkj dk Operation Perform dj ldrk gSA ;kuh fdlh Object A dk dksbZ Operation fdlh Object B ds fdlh Attributes dh fLFkfr (States) esa ifjorZu ugha dj ldrk gSA ,d Object A ds fofHkUu Attributes dh States dks Change djus dk vf/kdkj dsoy mlh Object A ds ikl gh gksrk gSA


Java in Hindi bl ckr dks ;fn Human Being ds mnkgj.k ls le>sa rks dksbZ Human Being Object Lo;a gh ;s fu.kZ; dj ldrk gS fd mls mlds fdlh Attribute dh fLFkfr esa ifjorZu djus ds fy, dksbZ Operation Perform djuk gS ;k ughaA ;kuh fdlh Human Being dks vius cky dVokus gSa ;k ugha] bl ckr dk fu.kZ; dsoy og Human Being gh ys ldrk gSA ,slk ugha gks ldrk fd ml Human Being ds cnys dksbZ nwljk Human Being ;s fu.kZ; djs vkSj fcuk mldh Permission fy, mlds cky dkV nsA ;kuh ,d gh Class ds fofHkUu Objects Hkh ,d nwljs ij fcuk Permission fy, fdlh Hkh izdkj dk Operation Perform djds fdlh nwljs Object ds Attributes dh fLFkfr esa ifjorZu ugha dj ldrs gSaA bl iwjs Discussion dk ;fn lkjka”k fudkysa rks ge fuEu lkjka”k izkIr dj ldrs gSa% 1 nqfu;k ds gj Object dks mlds lewg ds vk/kkj ij ,d Class ds :i esa Describe fd;k tk ldrk gSA 2 ,d ckj fdlh ,d Object ds vk/kkj ij Class dh Description cuk ysus ds ckn] ml Class ds ftrus pkgsa mrus Instances Create dj ldrs gSaA bu Instances dks gh Object dgk tkrk gSA 3 gj Object ds nks Components Attributes dh States o Object dh Ability gksrs gSa] ftuds vk/kkj ij ml Object dh Class dk Description rS;kj fd;k tkrk gSA 4 fdlh Objects ds Attributes dh States o mu Attributes dh States esa Object }kjk fd, tkus okys ifjorZuksa dh Description, bu nksuksa dks ,d lkFk feykdj ,d Entity ds :i esa Use djuk Encapsulation dgykrk gSA bl Entity dks gh Object dgrs gSa vkSj Encapsulation dh ;s izfØ;k Class ij Perform dh tkrh gSA 5 ,d Object ds Attributes dh fLFkfr (State) ds eku (Data) esa dsoy og Object gh fdlh Operation }kjk ifjorZu dj ldrk gS] vU; fdlh Hkh Object dks ;s vf/kdkj ugha gksrk gS] fd og fdlh nwljs Object ds Attributes dh State esa vius fdlh Operation }kjk ifjorZu djsaA bl fLFkfr esa fdlh Object ds Data dks dsoy og Lo;a gh Access dj ldrk gSA ;kuh ,d Object dk Data dsoy mlh Object ds fy, miyC/k jgrk gS] nwljs Objects fd fy, og Data Hide jgrk gSA blfy, Data ds bl izdkj ls fdlh Object ds vUnj Nqis gq, jgus ds rjhds (Structure) dks Data Hiding dgrs gSaA pfy,] vc Student dh Class dh Description dks iwjk djrs gSaA pwafd gesa Student ds lHkh Attributes irk gSa ftudh t:jr School ds Principal dks gSA ysfdu ,d School esa rks dbZ Students gksaxsA lkFk gh School esa u, Students dk Admission Hkh gksrk gksxk vkSj fdlh iqjkus Student dks School ls Transfer Hkh fd;k tkrk gksxk ;k fudkyk tkrk gksxkA dbZ ckj Student dh Information dks Update Hkh djuk iMrk gksxkA tSls ekuyks fd Student ds firk us viuk ?kj cny fy;k gS] rks Computer esa Student ds Address dks Hkh Change djuk gksxkA School esa rks dbZ Students gksrs gSa] blfy, fdlh fo”ks’k Student dks [kkstuk Hkh gksxk rkfd School ds Principal dks fdlh Student dh tkudkjh izkIr djus ds fy, lHkh Students ds Records dks uk Check djuk iMsA blh rjg ls ;fn lHkh Students ds Records dks ,d Øe esa Store fd;k tk,] rks Students ds Records dks Manage djuk ljy gksxkA bl rjg ls ge fdlh Student ds Records dks Manage djus ds fy, fuEukuqlkj Operations dh Description rS;kj dj ldrs gSa%


Java in Hindi //Ability Description (Operation Description) addNewStudent removeStudent updateStudent searchStudent sortStudent Computer esa fdlh Object ds fofHkUu Logical Operations dks tks fd ,d Object vius Attributes ds States dks Change djus ds fy, Perform djrk gS] mu lHkh Operations dks Methods ls Represent fd;k tkrk gSA Methods ds ckjs esa ge vkxs ppkZ djsaxs] ysfdu ;fn Student Class ds Operations dks ;fn Methods ds :i esa fy[kuk gks] rks ge Java esa Methods dks fuEukuqlkj Describe djrs gSa% //Ability Description (Operation Description) Access_Specifier Return_Data_Type addNewStudent(Arguments) { //Code Statements ; } Access_Specifier Return_Data_Type removeStudent(Arguments) { //Code Statements ; } Access_Specifier Return_Data_Type updateStudent(Arguments) { //Code Statements ; } Access_Specifier Return_Data_Type searchStudent(Arguments) { //Code Statements ; } Access_Specifier Return_Data_Type sortStudent(Arguments) { //Code Statements ; }

;fn ge Student Class dh iwjh Description Java Syntax ds vuqlkj fy[kuk pkgsa] rks ;s Class Description fuEukuqlkj gksxk% Student Class Defining class Student { //Attributes Description


Java in Hindi String studentName; String studentFName; String studentAddress; String studentCity; String studentTehsil; String studentDistrict; String studentState; byte studentClass; long studentContactNumber; long studentDateOfBirth; long studentDateOfAdmission; byte studentAge; String studentSerialNumber; String studentCast; //Ability Description (Operation Description) Access_Specifier Return_Data_Type addNewStudent(Arguments) { //Code Statements ; } Access_Specifier Return_Data_Type removeStudent(Arguments) { //Code Statements ; } Access_Specifier Return_Data_Type updateStudent(Arguments) { //Code Statements ; } Access_Specifier Return_Data_Type searchStudent(Arguments) { //Code Statements ; }

}

Access_Specifier Return_Data_Type sortStudent(Arguments) { //Code Statements ; }

vc gekjh Student Class iwjh rjg ls rS;kj gSA gesa dsoy blds Operations dks Define djuk gSA Operations dks Define djus ds ckn bl Class ds Objects Create fd, tk ldrs gSa vkSj muds lkFk Interaction fd;k tk ldrk gSA ;fn gesa bl Class ds Objects Create djus gksa] rks ge mlh izdkj ds Syntax dk iz;ksx djrs gSa] ftl izdkj ds Syntax dk iz;ksx djds ge dksbZ Integer izdkj dk Variable Create djrs


Java in Hindi gSaA ge ,slk blfy, dj ldrs gSa] D;ksafd Class ds :i esa ge ,d u, izdkj dk Data Type gh Develop djrs gSaA ;fn ljy “kCnksa esa dgsa rks geus ;gka ,d Student izdkj dk Data Type Create fd;k gS vkSj ge bl Data Type ds dbZ Variables Create dj ldrs gSa] ftUgsa Class dk Instance ;k Object dgrs gSaA mnkgj.k ds fy, ;fn ge fdlh Student ds Roll Number dks Store djus ds fy, ,d Integer Data Type dk Roll Number uke dk Variable Create djuk pkgsa] rks ge ;s Variable fuEukuqlkj Statement }kjk Create dj ldrs gSa% int rollNumber;

vkSj ;fn ge Student Data Type (Class) dk Rahul Sharma uke dk ,d Variable (Object) Create djuk pkgsa rks fuEukuqlkj dj ldrs gS% Student rahulSharma;

pwafd Primary Data Types Java ds Compiler esa Built–In gksrs gSa] blfy, tc ge fdlh Standard ;k Primary Data Type dk Variable Create djrs gSa] rks Compiler Lo;a gh ml Variable ds Data Type dh Size ds fglkc ls ml Variable ds fy, Memory Allocate dj nsrk gSA ysfdu tc ge fdlh User Defined Data Type ;kuh fdlh Class dk Object Create djrs gSa] rks mls Use djus ls igys gesa mls Memory Allocate djuh iMrh gSA fdlh Object dks Memory Allocate djus ds fy, Java ds new Operator dk iz;ksx fd;k tkrk gSA mnkgj.k ds fy, ;fn ge Rahul Sharma dks Computer esa Use o Access djuk pkgsa rks lcls igys rks gesa Rahul Sharma dks Student Class ds ,d Object ds :i esa Declare djuk gksxk vkSj mlds ckn Rahul Sharma dks Memory Allocate djuh gksxhA mlds ckn gh ge Rahul Sharma dks Computer esa Access dj ldrs gSaA ;s nksuksa dke ge fuEukuqlkj djrs gSa% Student rahulSharma; rahulSharma = new Student();

fdlh Class ds Object ds Data dks Manage djus ds fy, ml Class ds Object dks Object ds Data ij fofHkUu izdkj ds Operations Perform djus iMrs gSaA bu Operations dks Java esa Methods dgk tkrk gSA Methods Statements dk ,d ,slk lewg gksrk gS] tks mlds Object ds Data esa ifjorZu djus dk vf/kdkj j[krk gSA bUgsa vU; Procedural Languages esa Function dgk tkrk gSA fdlh Class esa Define fd;k x;k Method] ml Class ds Object ds Data dks Access djus dk dke djrk gSA nwljs “kCnksa esa dgsa rks fdlh Class ds Object ds Data dks Access djus ds fy, mlh Class ds fdlh Method dks Call djuk iMrk gSA og Call fd;k x;k Method gh ,d ek= ,slk lk/ku gksrk gS] tks ,d User dks ;s lqfo/kk nsrk gS fd og Object ds Data dks Access dj ldsA ;fn User fdlh Object ds fdlh Data dks Access djuk


Java in Hindi pkgrk gS] rks mls ml Method dks Call djuk iMrk gS] ftls ml Object dh Class esa Define fd;k x;k gSA mnkgj.k ds fy, ;fn ,d School dk Principal fdlh Student ds Record dks Update djuk pkgrk gS] rks mls mlh Student Class ds updateStudent Method dks Call djuk gksxk] D;ksafd dsoy og updateStudent Method gh ml Student Object ds Data dks Access dj ldrk gSA ;kuh fdlh Object ds Methods }kjk gh ml Object ds Data ds lkFk User Interact dj ldrk gSA blfy, bu Methods dks Interfaces Hkh dgrs gSa] D;ksafd ;s gh os ek/;e gksrs gSa ftuds }kjk ,d User fdlh Object ds Data ds lkFk Interact dj ikrk gSA fdlh Object ds Attributes ds eku esa ifjorZu djus (u;k eku Insert djus ;k eku dks Update djus ;k fQj eku dks Read djus) ;kuh Object ds Data ij fdlh izdkj dk Operation Perform djus ds fy, ml Object ds Class ds fdlh Method (Appropriate Operation) dks Call fd;k tkrk gSA bu Methods dks Call djus ds Java esa eq[;r% pkj rjhds gSa% 1 2 3

4

Method with Argument and Return Value Method with Argument but No Return Value Method with No Argument and No Return Value Method with No Argument but Return Value

Argument dks lkekU;r;k Parameters Hkh dgrs gSaA Arguments os eku gksrs gSa] tks Program dk User fdlh rjhds ls fdlh Object ds fdlh Attribute Field dks iznku djuk pkgrk gSA bu ekuksa ij Method ds vUnj vko”;drkuqlkj fdlh Hkh izdkj dk Operation Perform fd;k tk ldrk gSA

nkgj.k ds fy, User Arguments ds :i esa 2 Input djs] vkSj Program dh Requirements ds vuqlkj Method ml eku dk Square Kkr djs] rks ml eku dks Object ds Data ds :i esa Store fd;k tk ldrk gSA ;kuh Operation dh Requirement ds vuqlkj bu Arguments ij Operation Perform gks ldrs gSa vkSj bu Arguments ds ekuksa es ifjorZu Hkh vk ldrk gSA rhuksa izdkj ds Methods dks le>us ds fy, ge lcls igys ,d Camera Class cukrs gSaA ekuyks dh gekjh Camera Class fuEukuqlkj gS& Class Camera { //Instance Variables Representing State and Appearance of Camera }

//Operations to be performed on Instance Variable’s Values

,d Camera dh dqN eq[; Characteristics fuEukuqlkj gks ldrh gSa& 1 2 3 4

gj gj gj gj

Camera Camera Camera Camera

ds Modal dk dksbZ uke gksrk gSA dqN Photos [khaprk gSA dh dqN dher gksrh gSA dh Reel esa 36 Photos ds fy, Negatives gksrs gSaA


Java in Hindi vkSj bu Characteristics dh States o Appearance ds eku dks Change djus ds fy, ge bu ij fuEukuqlkj Operations Perform dj ldrs gSa& 1 gj Camera dk Photo [khapus ds fy, ,d Button Click gks ldrk gSA dqy [khaph xbZ Photographs dh Counting dj ldrk gSA 3 Camera ds Shutter dh Speed Change gks ldrh gSA 2

Camera dh Properties dks ge vklkuh ls Class esa Place dj ldrs gSaA ,slk djus ij Class fuEukuqlkj cu tk,xh% Class Camera { //Instance Variables Representing State and Appearance of Camera String modelName; int noOfPhotosTaken; int noOfTotalNegativesToBeTakenPhoto; float priceOfCamera; //Operations to be performed on Instance Variable’s Values }

vc gesa ;s ns[kuk gS fd tc fdlh Camera ds Click Button dks Press fd;k tkrk gS] rc D;k gksrk gSA ge le> ldrs gSa fd tc Hkh Click Button dks Press fd;k tkrk gS] rc Camera ,d Photo [khaprk gSA ;kuh noOfPhotosTaken uke ds Object ds Instance Variable dk eku ,d c< tkrk gS tcfd dqy Negatives dh la[;k ,d de gks tkrh gSA ;gka fdlh izdkj dk dksbZ ,slk eku Generate ugah gks jgk gS] ftls blh Class ;k fdlh vU; Class esa Use fd;k tk,] bl fy, ge dg ldrs gSa] fd ;s Method dksbZ eku return ugha djsxkA lkFk gh User dsoy Click Button dks Press djrk gS] blds vykok dqN Hkh ugha djrk gS] blfy, bl Method esa Argument ds :i esa Hkh dksbZ eku User iznku ugha dj jgk gSA ekuyks ge bl Method dk uke pressClickButton j[kuk pkgrs gSaA bl fLFkfr esa pwafd bl Method dk Return Value Hkh dqN ugha gS vkSj Argument Hkh dqN ugha gS] blfy, ge bls fuEukuqlkj Define djuk pkgrs gSA void pressClickButton(void) { //Increments the Number of Photographs Taken noOfPhotos = noOfPhotos + 1; }

tc Hkh User Click Button dks Press djrk gS] ml Camera Object ds dqy Photos dh la[;k ,d c< tkrh gSA [khaph xbZ Photos dh la[;k dsoy ,d gh blfy, c

Java in Hindi Abstract Data Types ,d Programmer tc fdlh Program dks fy[kuk pkgrk gS rks lcls igyh pht tks mls Handle djuh gksrh gS og gksrh gS leL;kA lkekU;r;k ge ,d Real Life Problem dks Face dj jgs gksrs gSa vkSj ge pkgrs gSa fd ml Real Life Problem dks Solve djus ds fy, ,d Computer Program cuk fy;k tk,A ysfdu Real Life Problems dh dbZ ckrsa gksrh gSaA dqN ckrsa leL;k ds lek/kku ds fy, t:jh gksrh gSa rks dqN ckrsa ml leL;k ds lek/kku ds fy, Qkyrw gksrh gSaA gesa tks Hkh Program cukuk gksrk gS] ml “Real Life” ls tqMh gqbZ leL;k dks Computer esa Data ds :i esa Feed djuk gksrk gS] rkfd Computer ml Data ij Processing dj ldsA leL;k dks Data ds :i esa foHkkftr djus ds fy, gesa leL;k dks le>uk gksrk gS] rkfd leL;k dh mu vko”;d ckrksa dks vuko”;d ckrksa ls vyx fd;k tk lds] tks ml leL;k ds lek/kku ds fy, mi;ksxh gks ldrh gSaA leL;k dks vPNh rjg ls le>us ds ckn lkjka”k ds :i esa tks vko”;d Details gesa izkIr gksrh gSa] mUgsa Computer esa Data ds :i esa bLrseky fd;k tk ldrk gSA fdlh “Real Life” Problem dks le> dj mldh mu vko”;d ckrksa dks tks fd leL;k ds lek/kku ds fy, mi;ksxh gks ldrh gSa] ys ysuk vkSj “ks’k vuko”;d ckrksa dks NksM nsuk] bl izfØ;k dks Abstraction dgk tkrk gSA bls fuEu fp= esa n”kkZ;k x;k gS% Create a model from a problem with abstraction

fdlh fc[kjh gqbZ leL;k dks lqy>kus ds fy, mls fp= esa crk, Model Box ds vuqlkj O;ofLFkr dj ysuk leL;k dk Abstraction dgykrk gSA ;gka Åij crk, x, fp= esa Model Box leL;k dk Abstract View n”kkZ jgk gS tgka Model Box esa dsoy leL;k ls lEcaf/kr Details gh gksrh gSa tks leL;k ds lek/kku dks izHkkfor djrh gSaA “ks’k vuko”;d Details dks gVk fn;k x;k gksrk gSA leL;k dk Abstraction djus ds ckn gekjs ikl leL;k ls lEcaf/kr dsoy mi;ksxh tkudkjh gh gksrh gS vkSj leL;k ls lEcaf/kr bu mi;ksxh tkudkfj;ksa ls gesa leL;k dh fo”ks’krkvksa dks ifjHkkf’kr djuk gksrk gSA bu fo”ks’krkvksa esa gesa fuEu nks ckrsa r; djuh gksrh gSa& 1

os Data dkSu ls gSa] tks fd leL;k esa izHkkfor gks jgs gSaA ;kuh fdl Data ij izfØ;k gks jgh gSA vkSj 238 Any Question or Suggestion, Just Discuss Here...

Java in Hindi 2

os izfØ;k,a dkSulh gSa tks Data ij Operations djrh gSa vkSj Data dh fLFkfr dks ifjofrZr djrh gSaA

bl izfØ;k dks le>us ds fy, ge ,d mnkgj.k ysrs gSaA ekuk fdlh Company dk Head vkrk gS vkSj vkils ,d ,slk Program cukus ds fy, dgrk gS] ftlls og vius Employees ds ckjs esa lkjh tkudkjh j[k lds vkSj tc ftl Employee ds ckjs esa pkgs mldh Detail izkIr dj ldsA bl leL;k esa lcls igys gekjk dke bl leL;k ds ewy mn~ns”; dks tkuuk gSA bl leL;k esa Administrator vkils vius Employees dk Bio-Data tkuuk pkgrk gSA ;kuh bl leL;k esa Employee izHkkfor gks jgk gSA blfy, ,d Employee ds ckjs esa tks Hkh tkudkfj;ka t:jh gks ldrh gSa] os lHkh Details Computer ds fy, Data gksaxhA pwafd Employee ,d “Real Person” gS blfy, gj Employee dh dbZ fo”ks’krk,a (Characteristics) gks ldrh gSa tSls%        

name size date of birth, shape social number room number hair color hobbies

fuf”pr :i ls Employee dh bu lHkh Qualities dh Administrator dks dksbZ t:jr ugha gksxhA buesa ls dsoy dqN gh ckrsa Administrator dh leL;k ls lEcaf/kr gksaxh] ftUgsa og tkuuk pkgsxkA ifj.kkeLo:i leL;k ds lek/kku ds fy, ge Employee dk ,d Model cukrs gSaA bl Model esa Employee dh dsoy mu fo”ks’krkvksa (Properties) dks gh fy;k tkrk gS] ftldh Administrator dks t:jr gks ldrh gSA tSls Employee dk uke] mldh tUe rkjh[k vkSj mldh Qualification, bu Properties dks Model (Employee) dk Data dgrs gSaA ;kuh ge ,d Employee dh fofHkUu Properties esa ls dsoy mu Properties dks gh leL;k esa mi;ksxh eku jgs gSa] ftudh tkudkjh Administrator ds fy, mi;ksxh gks ldrh gSA ;kuh ,d Employee dh dsoy mu ckrksa dks ys jgs gSa ftudh Administrator dks t:jr gS “ks’k dks NksM jgs gSaA blh izfØ;k dks Abstraction dgrs gSa ftlesa leL;k ls lEcaf/kr t:jh phtksa dks vU; fcuk t:jr dh phtksa ls vyx fd;k tkrk gSA gkykafd bl leL;k ds fy, Employee dh ftu Properties dks NksMk tk jgk gS] gks ldrk gS fd fdlh vU; leL;k ds lek/kku esa mUgha Properties dh t:jr gksA rks ml fdlh nwljh leL;k ds Abstraction esa izkIr gksus okyh t:jh ckrsa bl leL;k dh t:jh ckrksa ls vyx gksaxhA bl mnkgj.k ls ge le> ldrs gSa fd fdl izdkj ls ,d Abstract Model dk iz;ksx djds ,d “Real World Object” ;kuh ,d O;fDr dks Describe dj ldrs gSa vkSj fQj ml Real World Object dks Computer esa Logically Represent dj ldrs gSaA gkykafd vHkh Hkh ;s fooj.k iw.kZ ugha gSA ;gka dqN Operations Hkh ifjHkkf’kr fd, tkus pkfg,a]


Java in Hindi ftlls Administrator ml Abstract Employee dks Handle dj ldsA mnkgj.k ds fy, ;gka ,d ,slk Operation gksuk pkfg,] ftlls tc dksbZ u;k O;fDr Company esa vk, rks Program esa Hkh u, Employee dks Create fd;k tk ldsA ;kuh gesa ,sls Operations dks Hkh r; djuk gksxk ftudks Abstract Employee ij Perform fd;k tk ldsA gesa ;s Hkh r; djuk gksxk fd Company ds Employees ds Data dks dsoy os gh Operations Access dj ldsa ftUgsa ,slk djus ds fy, Define fd;k x;k gSA ,slk djus ij gesa”kk ;s fuf”pr jgsxk fd Data Elements mudh lgh fLFkfr esa gSaA mnkgj.k ds fy, ge ;s Check dj ldrs gSa fd D;k Input dh xbZ Date Valid gS ;k ughaA lkjka”k esa dgsa rks Abstraction ,d ,slk rjhdk gS ftlls tfVy “Real Life” Problem dks muds Data vkSj ¼Data ds eku dks Change djus okys½ Operations }kjk ,d Well Defined Unit ;k Entity ds :i esa O;ofLFkr fd;k tk ldrk gS] ftlesa leL;k ds Data o Data ij dke djus okys Operations lfEefyr :i ls ,d lkFk Combined jgrs gSaA tc fdlh leL;k ls izHkkfor gksus okys fofHkUu Data o mu Data ij dke djus okys fofHkUu Operations dks ,d bdkbZ ds :i esa ifjHkkf’kr fd;k tkrk gS] rks bl izfØ;k dks Encapsulation dgrs gSa vkSj bl Unit dks Entity ;k Object dgk tkrk gSA Java esa ge tks Class Develop djrs gSa] og ,d Abstract Data Type ;k u, izdkj dk Data Type gksrk gSA ftl rjg ls ;fn gesa Integer izdkj ds eku dks Computer esa Manage djuk gks] rks ge int (Class) ds Data Type dk ,d Variable (Instance ;k Object) Create djrs gSa vkSj ;fn gesa fdlh uke dks Computer esa Store djds Manage djuk gks rks ge String Data Type (Class) dk ,d Variable (Object) Create djrs gSa] mlh rjg ls Java esa tks Class cukbZ tkrh gS] og Class Hkh ,d u, izdkj dk Data Type gksrk gS vkSj ge bl Class ds Hkh Objects (Variables) Create djds mls Computer esa Store o Manage dj ldrs gSaA

;gka vkids fnekx esa ,d loky vk ldrk gS] fd tc gekjs ikl Basic izdkj ds Data Type gSa rks gesa u, Data Type cukus dh D;k t:jr gS \ bldk tokc ;s gS fd Basic izdkj ds Data Type ds Objects dh ,d ijs”kkuh ;s gS fd ge Computer esa dksbZ Hkh eku Lora= :i ls Store ugha djrs gSaA gj eku dk fdlh nwljs eku ls lEca/k gksrk gSA ;fn gesa dsoy ,d la[;k dks Computer esa Store djuk gks] rks ge int ;k float ;k double izdkj dk Object Create djds eku dks Computer esa Store dj ldrs gSaA ;fn gesa ,d gh Data Type ds dbZ eku Computer esa Store djds Manage djus gksa rks ge Array dk iz;ksx dj ldrs gSa] ysfdu tc gesa dbZ izdkj ds ekuksa dks ,d lewg ds :i esa Computer esa Store o Manage djuk gks] rc gesa ,d ,sls rjhds dh t:jr iMrh gS] ftlls ge fofHkUu izdkj ds Data Types dk iz;ksx dj ldsa vkSj mUgsa ,d lkFk ,d gh Object ds lUnHkZ esa Use dj ldsaA mnkgj.k ds fy, ;fn gesa dsoy ,d Student ds Roll Number dks Computer esa Store djuk gks] rks ge ,d int izdkj dk Variable Declare dj ldrs gSaA ;fn gesa nl Students ds Roll Number Store djus gksa rks ge int izdkj dk ,d Array Create dj ldrs gSa] ysfdu ;fn gesa ,d Student ds uke] Address] Contact Number, Class, City, State vkfn dbZ izdkj ds Data dks Compute esa Store djuk gks] rks gekjs ikl ,d ,slk rjhdk gksuk pkfg,] ftlls ge 240 Any Question or Suggestion, Just Discuss Here...

Java in Hindi ,d gh le; ij vko”;drkuqlkj int, float, double, char lHkh izdkj ds Data ds lewg ds lkFk izfØ;k dj ldsaA ;fn ,slk rjhdk uk gks rks ge ;s fdl rjg ls ;s r; djsaxs fd ge ftl Student ds uke dks Access dj jgs gSa] mlds firk dk ogh uke Computer Return djsxk tks geus Feed fd;k FkkA ,slk rHkh gks ldrk gS] tc gj Student ds Record ds lHkh Fields ,d nwljs ls Related gksa vkSj lHkh Fields ,d lkFk Access gksrs gksaA Class gesa ;gh lqfo/kk iznku djrk gSA ,d Class ds }kjk ge Real World Object dks ,d u, Data Type ds :i esa Computer esa Logically Describe dj ysrs gSa vkSj ml Description ds vk/kkj ij u, Data Type ds Objects Create djds mlh izdkj ls izfØ;k djrs gSa] ftl rjg ls mu Objects ds lkFk Real World esa izfØ;k dh tkrh gSA tc ge fdlh Class esa fofHkUu Instance Identifiers Declare djrs gSa vkSj mu Instance Identifiers dks Initialize ugha djrs gSa] rks mu Variables esa Default :i ls fuEukuqlkj eku Initialise gks tkrs gSa% Data Type

byte short int long float double char boolean abstract Data Type

Initial Value

0 0 0 0L 0.0 0.0 ‘\u000’ (null) false null

vc gesa irk gS fd ,d Class ds gesa”kk nks fgLls gksrs gSaA igys fgLls esa fdlh Real World Object dks Logically Computer esa Represent djus okys Attributes gksrs gSa vkSj nwljs fgLls esa mu Properties ;k Attributes esa ifjorZu djus okys Operations gksrs gSaA fdlh Class ds Object ds fofHkUu izdkj ds Attributes dks Represent djus ds fy, ge fofHkUu izdkj ds Data Types dk iz;ksx djrs gSa vkSj Object ds fofHkUu izdkj ds Attributes ds ekuksa esa vko”;drkuqlkj ifjorZu djus ds fy, ge Methods dk iz;ksx djrs gSaA pfy,] vc ge Box Class esa dqN Methods Add djrs gSaA

Adding Methods to Box Class gkykafd geus tks Box Class cukbZ gS] mlesa dsoy fdlh Box Object ds Data gh Store gks jgs gSaA fQj Hkh ;s Class vius vki esa iw.kZ gSA ysfdu ,slk lkekU;r;k gksrk ugha gSA lkekU;r;k ftruh Hkh Classes gksrh gSa] muds Data dks Access djus ds fy, muesa dqN Methods Hkh Define fd, tkrs gSaA ;s Methods gh Class ds fofHkUu Data ds lkFk izfØ;k djus ds fy, ,d Interface dh rjg dke djrs gSaA fdlh Class esa Methods Define djds ,d Class Creator Class ds Data dks General Use ls Hide dj nsrk gS] rkfd Object ds Data dks xyrh ls Modify uk fd;k tk ldsA ;kuh


Java in Hindi Data Hiding dh izfØ;k ls Class Creator fdlh Object ds Data Structure dks Abstraction izfØ;k }kjk Hide dj nsrk gS] ftlls Object ds Data lqjf{kr jgrs gSaA Box Class dks ,d mnkgj.k esa Use djds geus fdlh Box Object dk Volume Kkr fd;k FkkA ysfdu ;s Volume geus main() Method esa Kkr fd;k FkkA ;kuh Class ds Data dks main() Method esa Use fd;k FkkA ysfdu okLro esa Class ds Data dks Access djus okys ftrus Hkh Methods gksrs gSa] mUgsa Class ds vUnj gh Define dj fn;k tkrk gSA blls igys fd ge Class esa Volume Kkr djus dk Method Add djsa] igys ge Method dks ifjHkkf’kr djus

dh dksf”k”k djrs gSaA

lkekU; thou esa gj jkst ge gtkjksa dke djrs gSaA ysfdu lHkh izdkj ds dke ge vdsys ugha dj ldrs gSaA mnkgj.k ds fy, ekuyks fd fdlh Company esa Car cukbZ tkrh gSA rks Car cukus ds fy, ftrus Hkh dke fd, tkrs gSa] os lHkh dke ,d gh Company esa ugha gksrs gSaA tSls ;fn Company esa Car dh Body cukbZ tkrh gS] rks ;s t:jh ugha gksrk gS fd ogh Company Car dk Engine Hkh cuk,A bl fLFkfr esa Company Car ds Engine dks fdlh vkSj Company ls [kjhn ysrh gS vkSj viuh Car esa ml Engine dks Use dj ysrh gSA pfy,] ,d vkSj mnkgj.k ysrs gSaA Computer Assembler djus okyh cgqr lh Companies gSa] ysfdu lHkh Companies Computer dk Processor, Hard Disk, Cabinet, Keyboard, Monitor vkfn ugha cukrh gSaA cfYd ftl Company dk Monitor vPNk gksrk gS] og Company ml Company ls vius fy, Monitor Develop djok ysrh gSA ftl Company dk Keyboard vPNk gksrk gS] ml Company ls viuh Company ds Label dk Keyboard Develop djok ysrh gSA blh rjg ls Cabinet cukus okyh Company ls viuh Company ds Label dk Cabinet Develop djok fy;k tkrk gSA ;kuh dksbZ Computer cukus okyh Company Computer ds fy, t:jh lHkh Devices Lo;a ugha cukrh gS] cfYd vU; Companies }kjk viuh Requirement dks iwjk djok ysrh gSA gekjh ftl Class esa main() Method gksrk gS] mls ge og Company eku ldrs gSa] tks Computer cukus dk dke djrh gS vkSj main() Method dh Requirements dks iwjk djus ds fy, ftu vU; Methods dks Develop fd;k tkrk gS] mUgsa ge mu vU; Companies ds leku eku ldrs gSa] tks main() Method dh Requirements dks iwjk djrh gSaA main() Method o fdlh Hkh vU; Method esa fdlh izdkj dk ;fn dksbZ vUrj gksrk gS] rks og dsoy Method ds uke dk vUrj gksrk gSA ;fn main() Method ds uke main ds LFkku fdlh vU; uke dks Use dj fy;k tk, vkSj fdlh vU; Method other() ds uke other ds LFkku ij main dks Replace dj fn;k tk,] rks ;s other() Method gh main() Method cu tk,xkA

ftl rjg ls ge main() Method fy[krs gSa] mlh rjg ls ge fdlh vU; Method dks Hkh fy[k ldrs gSaA cl vUrj dsoy bruk gS fd main() Method ckdh ds vU; Methods dks Call djrk gS] mUgsa Use djrk gS vkSj User dh vko”;drkvksa dks iwjk djrk gSA Volume Kkr djus ds fy, geus main() Method esa fuEu Statement fy[kk Fkk% volume = cpuCabinet.length * cpuCabinet.height * cpuCabinet.width; System.out.println("Volume is " + volume);


Java in Hindi gesa bUgha Statements dks volume() Method esa fy[kuk gSA ysfdu pwafd ge ;s Method Box Class ds vUnj gh fy[ksaxs] blfy, gesa cpuCabinet.length ds LFkku ij dsoy length fy[kuk gksxkA ;kuh ;s Statement dqN fuEukuqlkj fy[kuk gksxk% volume = length * height * width; System.out.println("Volume is " + volume);

,slk blfy, gksrk gS D;ksafd tc fdlh Class ds Data dks Access djus okyk Member Method mlh Class esa Define fd;k tkrk gS] rc og Method viuh Class ds Data dks Directly Access dj ldrk gSA mls Dot Operator dk iz;ksx djus dh t:jr ugha iMrh gSA ysfdu tc fdlh Class ds Data dks Access djus okyk Method fdlh nwljh Class dk Member Method gksrk gS] rc mls Dot Operator ds Reference esa gh nwljs Class ds Data dks Access djuk iMrk gSA pwafd ge tks volume() Method Define dj jgs gSa] og Class ds vUnj gh Define fd;k tk,xk] blfy, gesa Dot Operator ds iz;ksx dh t:jr ugha gksxh cfYd ;s Method Directly Class ds Data dks Access djus esa l{ke gSA fdlh Hkh Method dks Create djus ds fy, geus igys Hkh crk;k gS fd gesa pkj ckrksa dh t:jr iMrh gSA 1 Method dk Access Specifier blds ckjs esa ge vkxs foLrkj ls ppkZ djsx a s] ysfdu ;gka ge blds dsoy public gh Define djsaxsA tc fdlh Method dks public Define fd;k tkrk gS] rc ml Method dks dksbZ Hkh vU; Method Call dj ldrk gS] ;kuh ml Method dk iz;ksx djds ml Method okyh Class ds Data dks dksbZ Hkh vU; Method Access dj ldrk gSA ;fn ge bls public ds LFkku ij private Declare djsa] rks fLFkfr cny tkrh gS] ftlds ckjs esa ge ckn esa ppkZ djsaxsA 2 Method dk Return Data Type tks Method fdlh izdkj dk eku Return djrs gSa] os Method ftl izdkj dk eku Return djrs gSa] mlh izdkj ds Data Type dks ;gka Use djuk gksrk gSA pwafd ge gekjs bl mnkgj.k esa volume() Method ls vHkh fdlh izdkj dk eku Return ugha djok jgs gSa] blfy, ge Return Value Data Type ds fy, void dk iz;ksx djsaxsA 3

Method dk uke Method dk uke og Identifier gksrk gS] ftldk iz;ksx djds dksbZ vU; Method bls Call dj ldrk gS vkSj blds }kjk fd, tkus okys dke dk Qk;nk mBk ldrk gSA ;kuh volume() Method fdlh Box Object dk Volume Kkr djus dk dke djrk gS] blfy, dksbZ Hkh vU; Method ;fn fdlh Box Object dk Volume izkIr djuk pkgrk gS] rks og bl volume uke }kjk gh volume() Method dh lqfo/kkvksa dks izkIr dj ldrk gSA Program Control dks tgka Hkh ;s uke feyrk gS] Program Control lh/ks gh bl volume() Method esa vkrk gS vkSj volume() Method ds Statements dk Execution dj nsrk gSA ftlls Box Object dk Volume izkIr gks tkrk gSA

4 Method ds Parameters ;k Arguments dbZ ckj tks Method fdlh vU; Class ds Method dks Call djrk gS] ml vU; Method dks dqN eku iznku djrk gSA ;s eku Call gks jgs Method ds fy, Arguments ;k Parameters dgykrs gSaA pwafd gekjs mnkgj.k Program esa main() Method volume Method dks fdlh izdkj dk dksbZ eku iznku ugha dj jgk gS] blfy,


Java in Hindi ge pkgsa rks Method ds Argument List ds LFkku ij void dk iz;ksx dj ldrs gSa ;k fQj Method ds Parenthesis dks Empty NksM ldrs gSaA bl Discussion ds vk/kkj ij ge gekjs volume Method dks fuEukuqlkj ifjHkkf’kr dj ldrs gSa% public void volume(void) { } or public void volume() { }

vc ge mijksDr nksuksa Statements dks fuEukuqlkj bl Method esa fy[k ldrs gSa& public void volume() { volume = length * height * width; System.out.println("Volume is " + volume); }

pwafd volume ,d double izdkj dk Variable gS] blfy, gesa bl Method esa ,d Statement }kjk bl Variable dks Declare djuk gksxkA ;s dke geus main() Method esa fuEukuqlkj fd;k Fkk& double volume;

;gh Statement gesa bl Method esa Hkh fuEukuqlkj Use djuk gksxk% public void volume() { double volume; volume = length * height * width; System.out.println("Volume is " + volume); }

;s ,d lkekU; lk Method gS tks fdlh Box Object ds Volume dks Screen ij Print djus dk dke djrk gSA ysfdu Java esa dksbZ Hkh Method Lora= :i ls Define ugha fd;k tk ldrk gS] cfYd gj Method dks ftl Class ds Object ds fy, Define djuk gksrk gS] mlh Class esa Define fd;k tkrk gSA blfy, gesa bl Method dks Box Class esa Define djuk gksxkA ;s dke ge fuEukuqlkj Box Class esa Modification djds dj ldrs gSa% Box Class class Box {


Java in Hindi //Attributes double width; double height; double length;

}

//Methods public void volume() { double volume; volume = length * height * width; System.out.println("Volume is " + volume); }

ftl rjg ls geus Box Class ds Data dks Access djus ds fy, Dot Operator dk iz;ksx fd;k Fkk] mlh rjg ls ge bl Box Class ds volume() Method dks Hkh Dot Operator }kjk Access dj ldrs gSaA bls le>us ds fy, ge fuEukuqlkj ,d Program Develop dj ldrs gSa% Program class Box { //Attributes double width; double height; double length;

}


public class BoxVolume { public static void main(String args[]) { Box cpuCabinet = new Box(); Box hardDisk = new Box(); cpuCabinet.length = 100; cpuCabinet.height = 70; cpuCabinet.width = 20; hardDisk.length = 10;


Java in Hindi hardDisk.height = 1.5; hardDisk.width = 6;

}

}

cpuCabinet.volume(); hardDisk.volume();

Output Volume is 140000.0 Volume is 90.0

bl Program dh dsoy vfUre nks Lines ,slh gSa] ftUgsa le>uk t:jh gSA cpuCabinet o hardDisk nks Box izdkj ds Objects gSa] ftudk Volume Calculate djuk gSA pwafd ;s nksuksa Objects ftl Class ds gSa ml Class esa gh volume() Method dks Define fd;k x;k gS vkSj ;s Method Box Class ds Data ij gh izfØ;k djrk gS] blfy, bUgsa Box Class ds fdlh Hkh Object ds fy, Call fd;k tk ldrk gSA tc Program Control cpuCabinet.volume() Statement ij vkrk gS] rks ;gka ls Program Control lh/ks gh Box Class esa Define fd, x, volume() Method esa tkrk gSA ml Method esa cpuCabinet Object ds Data ij Operation Perform gksrk gS vkSj cpuCabinet Object dk Volume Calculate gksrk gSA ;s Volume Screen ij Print gksus ds ckn Program Control okil vxys Statement hardDisk.volume() ij vkrk gSA fQj ls Box Class dk volume() Method hardDisk Box Object ds fy, Call gksrk gS vkSj Box Object dk Volume Calculate gks dj Screen ij Print gksrk gSA geus igys Hkh dgk gS fd fdlh Class ds ftrus Hkh Object Create fd, tkrs gSa] mu lHkh Objects ds vius Lo;a ds Data gksrs gSaA tSls cpuCabinet Object ds Lo;a ds Data cpuCabinet ds Actual Memory Location ij Store gksrk gS vkSj hardDisk Object ds Lo;a ds Data hardDisk Actual Memory Location ij Store gksrs gSaA blfy, tc volume() Method dks cpuCabinet Object ds fy, Call fd;k tkrk gS] rc Program Control cpuCabinet Object ds Data ds vk/kkj ij cpuCabinet dk Volume Calculate djrk gS vkSj tc hardDisk Object ds fy, bl Method dks Call fd;k tkrk gS] rc Program Control hardDisk Object ds Data ds vk/kkj ij Object ds Volume dks Calculate djrk gSA bl Program es ge ns[k ldrs gSa fd volume() Method uk gh main() Method ls Argument ds :i esa dksbZ eku izkIr dj jgk gS vkSj uk gh main() Method dks fdlh izdkj dk eku Return dj jgk gS] blfy, bl izdkj ds Method dks “Method without Argument and without Return Value” dgrs gSaA ;fn ge pkgsa rks bl ubZ Box Class ds volume() Method dks Return Value okys Method esa Convert dj ldrs gSaA ekuyks fd fdlh Box Object ds Volume dk Calculation rks Class ds volume() Method esa gksrk gS] ysfdu volume ds eku dks main() Method esa gh Screen ij Print djuk gSA


Java in Hindi rks bl fLFkfr esa gesa os Statements tks fd volume() Method esa Volume dks Screen ij Print djus dk dke djrs gSa] mUgsa volume() Method ls gVkuk gksxk vkSj Volume ds eku dks volume() Method ls Calling Method main() dks Return djuk gksxkA pwafd volume ,d double izdkj dk eku gS blfy, bl fLFkfr esa volume() Method dks fuEukuqlkj Declare djuk gksxk% public double volume() { double volume; volume = length * height * width; return volume; }

bl izdkj ds Method dks “Method with no Argument but Return Value” Method dgk tkrk gSA ;fn ge bl Method dks fiNys Program }kjk gh Use djuk pkgsa] rks fuEukuqlkj Program }kjk bls Use dj ldrs gSa% Program class Box { //Attributes double width; double height; double length;

}

//Methods public double volume() { double volume; volume = length * height * width; return volume; }

public class BoxVolumeWithReturnValue { public static void main(String args[]) { Box cpuCabinet = new Box(); Box hardDisk = new Box(); double volumeCPUCabinet; double volumeHardDisk; cpuCabinet.length = 100; cpuCabinet.height = 70;


Java in Hindi cpuCabinet.width = 20; hardDisk.length = 10; hardDisk.height = 1.5; hardDisk.width = 6; volumeCPUCabinet = cpuCabinet.volume(); System.out.println("Volume of CPU Cabinet is " + volumeCPUCabinet);

}

}

volumeHardDisk = hardDisk.volume(); System.out.println("Volume of Hard Disk is " + volumeHardDisk);

Output Volume of CPU Cabinet is 140000.0 Volume of Hard Disk is 90.0

bl Program esa lcls T;knk egRoiw.kZ Statement nks gh gSa] ftUgsa Bold fd;k x;k gSA tc cpuCabinet Object ds fy, Class ds volume() Method dks Call fd;k tkrk gS] rc Program Control Class ds Volume() Method esa tkrk gS vkSj cpuCabinet dk Volume Calculate djrk gSA ysfdu bl Volume ds eku dks Print ugha djrk] cfYd ml main() Method dks Return dj nsrk gSA bl Return fd, x, eku dks volumeCPUCabinet tks fd ,d double izdkj dk Variable gS] izkIr dj ysrk gS] ftls vxys Println() Method }kjk Screen ij Print dj fn;k tkrk gSA blh rjg ls hardDisk Box Object ds fy, Hkh volume() Method Call gksrk gS] tks hardDisk Box Object ds Volume dks Calculate djrk gSA bl Calculated Volume ds eku dks volume() Method main() Method dks Return dj nsrk gS] ftls volumeHardDisk uke dk main() Method esa Declare fd;k x;k double izdkj dk Variable izkIr dj ysrk gSA vxys Statement esa bl Variable esa Stored eku dks Screen ij Print djok fn;k tkrk gSA fiNys Program esa ge ns[k ldrs gSa fd Box Class ds volume() Method ds Return Type dks double izdkj dk Declare fd;k x;k gS vkSj lkFk gh blls tks eku return Statement }kjk Return fd;k tk jgk gS] og Hkh double izdkj dk gSA main() Method esa Hkh Box Class ds ftu Hkh Objects dk Volume Calculate djuk gS] mu lHkh ds Volume ds eku dks izkIr djus ds fy, double izdkj ds Variable dk gh iz;ksx fd;k x;k gSA ;kuh lHkh LFkkuksa ij double izdkj ds Variables gh Declare fd, x, gSaA ,slk blfy, fd;k tkrk gS] D;ksafd Java dk Compiler Type Compatibility ds izfr vR;f/kd laosnu”khy gSA ;fn ge bu rhuksa LFkkuksa esa ls fdlh Hkh LFkku ij double ds LFkku ij fdlh Hkh vU; Data Type dk iz;ksx djrs gSa] rks Compiler gesa ,d Compile Time Error iznku djrk gS vkSj Program dks Compile ugha gksus nsrkA blfy, tc fdlh Method ls dksbZ eku Return djok;k tk jgk gks] rc bl ckr dk fo”ks’k /;ku j[kuk t:jh gksrk gSA pfy,] vc ,d mnkgj.k ns[krs gSa ftlesa fdlh Method esa Parameters Pass fd, tk jgs gSaA ekuyks fd gesa nks la[;kvksa dks tksMus ds fy, ,d Method Create djuk gSA pwafd ge pkgrs gSa


Java in Hindi fd ;s nksuksa la[;k,a Program esa add() Method esa Argument ds :i esa iznku djuk pkgrs gSa] bl fLFkfr esa add() Method dks fuEukuqlkj Declare djuk gksxk% public void add(int firstValue, int secondValue) { int result; result = firstValue + secondValue; System.out.println(“Total is “ + result); }

bl Method esa ftu nks la[;kvksa dks tksMuk gksrk gS] mUgsa Argument ds :i esa Method esa Pass dj fn;k tkrk gSA ;fn ge bl Method dks fdlh main() Method esa Use djuk pkgsa rks fuEukuqlkj Code }kjk Use dj ldrs gSa gkykafd ge tkok esa Practically ,slk ugha dj ldrs gSa% add(12, 30);

;s Statement gesa fuEu Output iznku djrk gS& Total is 42

tc fdlh Calling Method esa add Method dks Call fd;k tkrk gS vkSj mnkgj.k Lo:i mlesa (12, 30) eku iznku fd;k tkrk gS] rc eku 12 add() Method ds firstValue uke ds Variable esa Store gks tkrk gS vkSj eku 30 add() Method ds nwljs Argument secondValue esa Store gks tkrk gSA ;fn ge bu ekuksa dks Change Hkh dj nsa rks Hkh add() Method esa dksbZ ifjorZu djus dh t:jr ugha gksrh gSA ekuyks fd ge add(40, 20) Statement dks Use djrs gSa] rks eku 40 add() Method ds firstValue Variable esa Store gks tkrk gS vkSj eku 20 add() Method ds secondValue Argument esa Store gks tkrk gSA fQj add() Method bu nksuksa ekuksa dks tksMdj Result dks Output esa Print dj nsrk gSA pwafd geus Parameter ds :i esa Integer izdkj ds Data Type dk Variable Declare fd;k gS] blfy, ;fn bl Method esa fdlh vU; Data Type dk eku Argument ds :i esa Pass fd;k tk,] rks Program Error Generate djrk gSA ekuyks fd gesa 12.5 dks 20 ls tksMuk gS] rks ge fuEukuqlkj add() Method }kjk ;s dke ugha dj ldrs gSa% add(12.5, 20);

D;ksafd add() Method esa tks igyk eku firstValue Variable esa Store gksus ds fy, Pass fd;k tk,xk] og double izdkj dk eku gS] tcfd firstValue Variable Integer izdkj dk gSA ,sls esa double izdkj dk eku Integer izdkj ds Variable esa Store ugha gks ldrkA ;kuh ge bl izdkj ls add() Method dks Use ugha dj ldrs gSaA ;fn gesa bl izdkj ds eku dks tksMuk gks rks gesa fuEukuqlkj add() Method dk ,d nwljk Version cukuk gksxk&% public add volume(double firstValue, int secondValue) { double result;


Java in Hindi }

result = firstValue + secondValue; System.out.println(“Total is “ + result);

vc ge mijksDr Statement }kjk add() Method dks Call dj ldrs gSaA Arguments o Parameters esa vUrj gksrk gSA geus add() Method esa tks firstValue o secondValue uke ds Variables Declare fd, gSa] bUgsa Parameters dgrs gSaA Parameters fdlh eku dks Store djus dk dke djrs gSa vkSj add() Method dks Call djrs le; tks eku geus dks’Bd esa iznku fd;k gS] tSls (12, 30) vkfn] rks bu ekuksa dks Argument dgrs gSaA mijksDr nksuksa Methods “Method with Argument but no Return Value” ds mnkgj.k gSaA ekuyks fd main() Method esa Box Class dk Object Create djus ds ckn ge Object ds Dimension dks Hkh Define djuk pkgrs gSaA bl dke dks djus ds fy, ge fuEukuqlkj ,d setDimension() Method Create dj ldrs gSa% public void setDimension(double len, double wid, double hei ) { length = len; width = wid; height = hei; }

bl Method dks Hkh ;fn ge Box Class ds Member Method ds :i esa ys ysa] rks bl Method dk iz;ksx djds ge Box Class ds fdlh Hkh Object dks Initialize dj ldrs gSaA bls le>us ds fy, fuEUk Program nsf[k,% Program class Box { //Attributes double width; double height; double length; //Methods public double volume() { double volume; volume = length * height * width; return volume; } public void setDimension(double len, double wid, double hei) { width = wid; length = len; height = hei; }


Java in Hindi } public class BoxDimension { public static void main(String args[]) { Box cpuCabinet = new Box(); Box hardDisk = new Box(); double volumeCPUCabinet; double volumeHardDisk; cpuCabinet.setDimension(20, 30, 40); hardDisk.setDimension(21,12,3); volumeCPUCabinet = cpuCabinet.volume(); System.out.println("Volume of CPU Cabinet is " + volumeCPUCabinet);

}

}



bl Program esa Hkh nks Lines gh lcls T;knk egRoiw.kZ gSa ftUgsa Program esa Bold fd;k x;k gSA tc cpuCabinet ds fy, setDimension Method dks Call fd;k tkrk gS vkSj Method ds Parenthesis esa (20, 30, 40) eku iznku fd;k tkrk gS] rc ;s eku Øe”k% len, wid o hei uke ds rhu Variables dks izkIr gks tkrk gSA fQj bu ekuksa dks Class ds rhuksa Instance Variables ;kuh length, width o height dks Assign dj fn;k tkrk gSA bl izdkj ls Box Object ds rhuksa Variables dks main() Method ls iznku fd, tkus okys Arguments }kjk Initialize fd;k tk ldrk gSA pfy,] ge Volume Method esa fuEukuqlkj ifjorZu djds ,d “Method with Argument and Return Value” izdkj dk Method Create djrs gSa] tks fd fuEukuqlkj gS% public double volume(Box temp) { double volume; volume = temp.length * temp.height * temp.width; return volume; }

ftl rjg ls ge fdlh Basic izdkj ds Variable dks fdlh Method esa Argument ds :i esa Pass dj ldrs gSa] mlh rjg ls ge fdlh Class ds Object dks Hkh fdlh Method esa Argument ds :i esa Pass dj ldrs gSaA bl izfØ;k dks fuEu Program }kjk le>k;k x;k gS%


Java in Hindi Program class Box { //Attributes double width; double height; double length; //Methods public double volume(Box temp) { double volume; volume = temp.length * temp.height * temp.width; return volume; }

}

public void setDimension(double len, double wid, double hei) { width = wid; length = len; height = hei; }

public class BoxVolumeWithBoxObjectArgument { public static void main(String args[]) { Box cpuCabinet = new Box(); Box hardDisk = new Box(); double volumeCPUCabinet; double volumeHardDisk; cpuCabinet.setDimension(20, 30, 40); hardDisk.setDimension(21,12,3); volumeCPUCabinet = cpuCabinet.volume(cpuCabinet); System.out.println("Volume of CPU Cabinet is " + volumeCPUCabinet);

}

}

volumeHardDisk = hardDisk.volume(hardDisk); System.out.println("Volume of Hard Disk is " + volumeHardDisk);



Java in Hindi bl Program esa ftl Object ds fy, volume() Method dks Call fd;k tkrk gS mlh Object dks ,d Argument ds :i esa volume() Method esa Hkst fn;k tkrk gSA volume() Method esa ml Object ds lHkh eku ,d temp uke ds Temporary Object esa Store gks tkrs gSaA fQj Dot Operator ds iz;ksx }kjk ge ml Object ds fofHkUu Data Members dks Access djds Object dk Volume Kkr dj ysrs gSa vkSj Volume() dks Calling Method main() esa Return dj nsrs gSaA

Methods Overloading

tkok esa ge ,sls Methods Create dj ldrs gSa ftuds uke rks leku gksa ysfdu muds Parameter List o Definitions vyx gksaA bl izfØ;k dks Method Overloading o ,sls Methods dks Overloaded Methods dgrs gSaA Method Overloading dk iz;ksx rc fd;k tkrk gS tc Objects dks ,d gh rjg ds dke djus gksrs gSa ysfdu Input Parameters vyx&vyx izdkj ds gksrs gSaA tc ge ,d Object ds fy, Method Call djrs gSa] rc tkok Method ds uke vkSj mlds ckn Parameter dh la[;k o Parameters ds Type dks Check djds ;s r; djrk gS fd mls Object ds fy, fdl Method dks Call djuk gSA bl izfØ;k dks tkok esa Polymorphism Hkh dgk tkrk gS] D;ksafd Java Interpreeter }kjk ,d gh uke o vyx&vyx Parameter List }kjk vyx&vyx Method dks Call fd;k tkrk gSA Overloaded Method Create djus ds fy, gesa dsoy bruk djuk gksrk gS fd leku izdkj ds dke djus okys fofHkUu Methods ds uke leku Define fd, tk,a o lHkh Methods ds Parameter dh la[;k ;k Parameters ds Data Type ;k nksuksa dks lHkh Methods esa vyx izdkj dk j[kk tk,A ;kuh gj Method ds fy, Arguments ds Data Type ;k la[;k Unique gksuh pkfg,A /;ku nsa fd Method Overloading esa Method ds Return Type dk dksbZ Role

ugha gksrk gSA bls le>us ds fy, ,d mnkgj.k nsf[k,% class Room { float length; float breadth; Room(float x, float y) { length = x; breadth = y; }

//Constructor1

Room(float x){ length = breadth = x; }

}

int area(){ return (length * breadth); }


Java in Hindi this Keyword

fiNys Program esa geus ns[kk fd Class dk volume() Method mlh Object ds Data Members dks Use djrk gS] ftlds fy, volume() Method dks Call fd;k tkrk gSA ;kuh volumeCPUCabinet = cpuCabinet.volume(cpuCabinet); volumeHardDisk = hardDisk.volume(hardDisk);

tc gesa gekjs Program esa bl rjg ls fdlh Object dks mlh Method esa Argument ds :i esa Pass djuk iMrk gS] ftl Object ds fy, Method dks Call fd;k tkuk gksrk gS] rc ge this Keyword dk iz;ksx djds Object ds Data Members dks Access dj ldrs gSaA mnkgj.k ds fy, fuEu Method dks nsf[k,% public double volume(Box temp) { double volume; volume = temp.length * temp.height * temp.width; return volume; }

bls fuEukuqlkj Hkh fy[k ldrs gSa% public double volume() { double volume; volume = this.length * this.height * this.width; return volume; }

;s Method Hkh ogh dke djrk gS tks dke fiNyk Method djrk gSA fdlh Member Method ds vUnj this Keyword gesa”kk mlh Object dks Refer djrk gS ftlds fy, Method dks Call fd;k tkrk gSA gekjs fiNys Program esa ;fn ge volume() Method ds bl Version dks fiNys Version ds LFkku ij Replace dj nsa] rks ge bl Program dks fuEukuqlkj Hkh fy[k ldrs gSa% Program class Box { //Attributes double width; double height; double length; //Methods public double volume() { double volume; volume = this.length * this.height * this.width; return volume;


Java in Hindi }

}

public void setDimension(double len, double wid, double hei) { width = wid; length = len; height = hei; }

public class BoxVolumeWithBoxObjectArgument { public static void main(String args[]) { Box cpuCabinet = new Box(); Box hardDisk = new Box(); double volumeCPUCabinet; double volumeHardDisk; cpuCabinet.setDimension(20, 30, 40); hardDisk.setDimension(21,12,3); volumeCPUCabinet = cpuCabinet.volume(); System.out.println("Volume of CPU Cabinet is " + volumeCPUCabinet);

}

}



bl Program esa fuEukuqlkj nksuksa Statements esa bl Modified volume() Method dks Use fd;k x;k gS% volumeCPUCabinet = cpuCabinet.volume(); volumeHardDisk = hardDisk.volume();

tc igyk Statement Execute gksrk gS rc volume() Method esa this Keyword ds dkj.k cpuCabinet Object ds Data Members Access gksrs gSa vkSj cpuCabinet dk Volume Calculate djrs gSa tcfd nwljs Statement ds Execution ij volume() Method dk this Keyword hardDisk Object ds Data Members dks Access djds HardDisk dk Volume Calculate djrk gSA


Java in Hindi Automatic Garbage Collection

pwafd ge ns[k pqds gSa fd fofHkUu Classes ds Objects Program ds Run Time esa new Operator ds iz;ksx }kjk Dynamically Create gksrs gSa] blfy, bu Objects dh t:jr uk gksus ij bUgsa Destroy gksuk Hkh t:jh gksrk gS] rkfd tks Memory ;s Objects Reserve djrs gSa] og Memory dksbZ vU; Variable ;k Object Use dj ldsA tkok esa Memory Releasing dk ;s dke Automatically gksrk gSA ftl rduhd }kjk tkok esa ;s dke gksrk gS] mls Garbage Collection dgrs gSaA tc fdlh Actual Memory Block ds fy, Reference ds :i esa dksbZ Object miyC/k ugha gksrk gS] rc tkok dk Compiler ;s ekurk gS fd ml Object dh t:jr ugha gS vkSj Compiler ml Object dh Memory dks Release dj nsrk gSA tkok esa fofHkUu izdkj ls Use gksus okys fofHkUu izdkj ds Objects dks Release djus ds fy, fofHkUu izdkj ds Operations Implement gksrs gSaA gesa fdlh Object dh Memory dks Release djus dh fpUrk djus dh t:jr ugha gksrh gS] D;ksafd tkok dk Compiler ;s dke t:jr ds vuqlkj fofHkUu Internal rjhdksa ls Lo;a gh djrk jgrk gSA

Finalize() Method

dbZ ckj gesa ,slh t:jr gksrh gS fd Object Destroy gksus ls igys dqN fo”ks’k dke djs] mlds ckn Destroy gksA mnkgj.k ds fy, tc dksbZ Object Non-Java Resources tSls fd File Handle ;k Windows Character Font dks Hold djrk gS] rc Object ds Destroy gksus ls igys bu fo”ks’k Resources dks Release djus dk dke Automatically ugha gksrk gSA bl fLFkfr esa gesa gh bu Resources dks Release djuk gksrk gSA bu Resources dks Release djus ds fy, Java gesa ,d fo”ks’k Mechanism Provide djrk gS ftls Finalization dgrs gSaA bl Finalization Process dk iz;ksx djds ge ,sls dke Define dj ldrs gSa] tks Object ds Destroy gksus ls igys Perform gksrs gSaA fdlh Class esa Finalize Method dks Add djus ds fy, gesa Class esa dsoy ,d finalize() Method dks Define djuk gksrk gSA Java Compiler bl Method dks Automatically ml le; Call dj ysrk gS] tc dksbZ Object Destroy gks jgk gksrk gSA bl Method esa ge os Actions Specify djrs gSa] tks Object ds Destroy gksus ls igys Perform djus gksrs gSaA Garbage Collector le;≤ ij Run gksrk jgrk gS vkSj ftu Objects ds References fdlh Memory Block dks Refer ugha dj jgs gksrs gSa] mu Objects dks Release djrk jgrk gSA blls igys fd ,slk dksbZ Object iwjh rjg ls Memory Release djs] Java finalize() Method dks Execute dj nsrk gSA

lkekU;r;k bl Method dks fdlh Object ds fy, Use ugha fd;k tkrk gSA tkok Compiler Lo;a gh bls vko”;drkuqlkj Use djrk jgrk gSA gesa gekjs Program esa fdlh lkekU; dke ds fy, bl Method dk iz;ksx ugha djuk pkfg,A bl Method dks ge fuEukuqlkj Define dj ldrs gSa% protected void finalize() { //Finalization Codes goes here. }


Java in Hindi ge ns[k ldrs gSa fd bl Definition esa geus public ds LFkku ij protected Access Specifier dk iz;ksx fd;k gSA tc fdlh Method dks protected Declare fd;k tkrk gS] rc bldk eryc ;s gksrk gS fd ;s Method Class ls ckgj fdlh Hkh rjg ls Access ugha fd;k tk ldrk gSA ,sls Method ds lkFk tks Hkh izfØ;k gksrh gS] og Class ds vUnj gh gksrh gSA Access Specifier ds ckjs esa vkxs ge foLrkj ls i
Methods Overloading

Method Overloading Java dk ,d ,slk Concept gS ftlesa ge ,d gh Class esa ,d gh uke ds dbZ Methods Create dj ldrs gSa vkSj lHkh Methods vyx&vyx izdkj ls dke djrs gSaA tc fdlh Class esa ,d gh uke ds ,d ls vf/kd Methods Create fd, tkrs gSa] rks bl izdkj ds Methods dks Overloaded Methods dgrs gSaA

mnkgj.k ds fy, eku yks fd gesa fdlh Integer la[;k dk Square Kkr djus ds fy, ,d Method fy[kuk gSA ge ;s Method fuEukuqlkj fy[k ldrs gSa% public int intSquare( int number ) { int square = number * number; return square; }

ekuyks gesa 10 dk Square Kkr djuk gS] rks 10 dk Square Kkr djus ds fy, bl Method dks ge fuEukuqlkj Call dj ldrs gSa% intSquare(10);

vc ;fn gesa fdlh double izdkj ds eku dk Square Kkr djuk gks] rks gesa fuEukuqlkj ,d vkSj Square() Method Create djuk gksxk% public double doubleSquare( double number ) { double square = number * number; return square; }

blh rjg ls ;fn gesa long izdkj ds eku dk Square Kkr djuk gks] rks gesa fuEukuqlkj ,d vkSj Method Create djuk gksxk% public long longSquare( long number ) { long square = number * number; return square; }

;fn ge /;ku ls ns[ksa rks dsoy fdlh la[;k dk Square Kkr djus ds fy, la[;k ds Data Type ds vuqlkj gesa fuEukuqlkj rhu uke /;ku j[kus gksaxs%


Java in Hindi intSquare() doubleSquare() longSquare()

;fn dqN ,slk gks lds fd ,d Programmer dks dsoy ,d gh uke /;ku j[kuk iMs vkSj Program Lo;a ;s r; dj ys fd mls fdl izdkj ds eku ds fy, fdl Method dks Use djuk gS] rks Programmer ds fy, dqN vklkuh gks tk,xh vkSj mls ,d gh izdkj ds dke ds fy, ,d ls vf/kd Methods ds uke ;kn j[kus dh t:jr ugha gksxhA tkok esa ge mijksDr rhuksa Methods dks leku uke ns ldrs gSaA ;kuh ge ;fn mijksDr rhuksa Methods dks vyx&vyx uke nsus ds ctk; dsoy square() uke ns nsa] vkSj ckdh iwjh Description dks T;ksa dk R;ksa fuEukuqlkj fy[k nsa] rks Hkh tkok dk Compiler dksbZ Error Generate ugha djrk gSA public int square( int number ) { int square = number * number; return square; } public double square( double number ) { double square = number * number; return square; } public long square( long number ) { long square = number * number; return square; }

;fn ge bu rhuksa Methods dks fdlh Class esa Define dj nsa] rks bu Methods dks Overloaded Methods dg ldrs gSa] D;ksafd bu lHkh Methods ds uke leku gSaA pfy,] bls le>us ds fy, ge CalculateSquare Class Develop djrs gSa] tks fd fuEukuqlkj gS% class CalculateSquare { public void square() { System.out.println("No Parameter Method Called"); } public int square( int number ) { int square = number * number; System.out.println("Method with Integer Argument Called"); return square;


Java in Hindi } public double square( double number ) { double square = number * number; System.out.println("Method with Double Argument Called"); return square; }

}

public float square( float number ) { float square = number * number; System.out.println("Method with float Argument Called"); return square; }

bl Class dk iz;ksx ge fdlh Program esa dj ldrs gSaA Methods dh Overloading dks Practically le>us ds fy, fuEu Program nsf[k,% Program public class OverLoadedMethodDemonstraton { public static void main(String [] args) { CalculateSquare firstNumber = new CalculateSquare(); CalculateSquare secondNumber = new CalculateSquare(); CalculateSquare thirdNumber = new CalculateSquare(); CalculateSquare forthNumber = new CalculateSquare(); int intResult; double doubleResult; float floatResult; forthNumber.square(); intResult = firstNumber.square(11); System.out.println("Value of integer = " + intResult); doubleResult = secondNumber.square(10.25); System.out.println("Value of double = " + doubleResult);

}

}

floatResult = thirdNumber.square(2.4f); System.out.println("Value of float = " + floatResult);

Output No Parameter Method Called


Java in Hindi Method with Integer Argument Called Value of integer = 121 Method with Double Argument Called Value of double = 105.0625 Method with float Argument Called Value of float = 5.76

vki lksp ldrs gSa fd tkok Compiler ;s fdl rjg ls r; djrk gS fd mls fdl eku ds fy, fdl Method dks Call djuk gS] tcfd Class esa Define fd, x, lHkh Methods ds uke leku gS\a bl loky dk tokc ;s gS fd tkok Compiler Method dks Call djrs le; tks eku Argument ds :i esa Method ds Parenthesis esa iznku fd;k tkrk gS] ml eku ds Data Type ds vk/kkj ij ;s r; djrk gS] fd mls Overloaded Method ds fdl Version dks Call

djuk gSA

geus gekjs Program esa lcls igys square() Method ds Parenthesis esa dksbZ Argument iznku ugha fd;k gSA bl fLFkfr esa Compiler Class ds ml Method dks Call djrk gS] ftlesa Argument dks izkIr djus ds fy, fdlh Parameter dks Define ugha fd;k x;k gSA ;kuh Compiler Class ds fuEu Method dks forthNumber Object ds fy, Call djrk gS% public void square() { System.out.println("No Parameter Method Called"); }

blh rjg ls tc firstNumber Object ds fy, square() Method dks Call fd;k tkrk gS vkSj Argument ds :i esa ,d Integer izdkj dk eku Method ds Parenthesis esa iznku fd;k tkrk gS] rc Compiler square() Method ds ml Version dks Call djrk gS] ftlesa Parameter ds :i esa ,d Integer izdkj dk Argument izkIr djus ds fy, ,d Variable Declare fd;k x;k gSA ;kuh% intResult = firstNumber.square(11); Statement ds Reference esa fuEu Method Call gksrk gS% public int square( int number ) { int square = number * number; System.out.println("Method with Integer Argument Called"); return square; }

blh rjg ls tc fuEu Statement Execute gksrk gS% floatResult = thirdNumber.square(2.4f); 260 Any Question or Suggestion, Just Discuss Here...

Java in Hindi rc bl Statement ds Reference esa square() Method dk fuEu Version Execute gksrk gS% public float square( float number ) { float square = number * number; System.out.println("Method with float Argument Called"); return square; }

bl rjg ls ge ,d gh uke ds ,d ls vf/kd Methods dks fdlh Class esa Define dj ldrs gSa] ftls Method Overloading djuk dgrs gSa vkSj bl rjg ls Define fd, x, Methods ds Arguments ds Data Type ds vk/kkj ij tkok dk Compiler Lo;a gh fdlh Object ds fy, mfpr Method Call dj ysrk gSA

Constructors

nqfu;k dk dksbZ Hkh Real World Object ,slk ugha gksrk gS] ftlds fofHkUu Attributes dk Object ds Create gksrs le; dksbZ eku uk gks vkSj lHkh eku ckn esa Set fd, tkrs gksaA ;kuh ekuyks fd dksbZ Company ,d cpuCabinet cukrh gSA rks Company dksbZ Hkh cpuCabinet ,slk ugha cuk ldrh ftlds fuekZ.k ds le; ml cpuCabinet Object dk dksbZ Length, width o Height uk gksA tks Hkh cpuCabinet Company cuk,xh ml gj cpuCabinet dk dksbZ uk dksbZ izkjfEHkd Dimension t:j gksxkA blh Concept ds vk/kkj ij tkok esa Hkh ;s lqfo/kk iznku dh xbZ gS fd fdlh Hkh Class dk dksbZ Hkh Object Create gksrs le; mlesa izkjfEHkd eku Initialized gks ldsA Create gksus okys Object esa Object ds Create gksrs le; gh dqN izkjfEHkd eku Initialize djus ds fy, ,d Method Create fd;k tkrk gSA bl Method dks Constructors dgrs gSaA Constructor fdlh Class dk ,d ,slk Member Method gksrk gS] ftldk uke ogh gksrk gS tks ml Class dk uke gksrk gS] ftlesa ;s Member Method gksrk gSA mnkgj.k ds fy, ;fn ge Box Class dk Constructor Define djuk pkgsa rks ;s Constructor Box Class dk ,d Member Method gksxk vkSj bl Method dk uke Hkh Box() gh gksxkA

pwafd Constructor dk ogh uke gksrk gS tks Class dk uke gksrk gS] blfy, tc Hkh ge ml Class dk dksbZ Object Create djrs gSa] rks Object ds Create gksrs gh ;s Constructor Method Execute gks tkrk gSA blfy, ge bl Method esa fdlh Object dks iznku fd, tkus okys izkjfEHkd eku iznku dj nsrs gSa vkSj tSls gh ge fdlh Class dk dksbZ Object Create djrs gSa] ml Class dk ;s Constructor Execute gks dj Create gksus okys Object ds fofHkUu Instance Variables dks Initialize dj nsrk gSA Constructors dh t:jr gesa blfy, Hkh iMrh gS D;ksafd tc Hkh dksbZ Object Create gksrk gS rks mldk dksbZ uk dksbZ izkjafHkd eku Hkh t:j gksrk gSA blfy, ;fn ge Constructors dk iz;ksx ugha djrs gSa] rks Object Create gksus ds ckn gesa ml Object ds fofHkUu Instance Variables dks fofHkUu eku Initialize djus iMrs gSaA bl dke dks djus ds fy, ge ,d Initialize() uke dk Member Method Hkh Create dj ldrs gSa] ysfdu ,slk djus ij gj Object ds fy, bl Method dks Call djuk iMrk gSA


Java in Hindi Program class Box { //Attributes double width; double height; double length; //Methods public double volume() { double volume; volume = this.length * this.height * this.width; return volume; } public void initializeObject(double len, double wid, double hei) { width = wid; length = len; height = hei; } } public class BoxVolumeWithBoxObjectArgument { public static void main(String args[]) { Box cpuCabinet = new Box(); Box hardDisk = new Box(); double volumeCPUCabinet; double volumeHardDisk; cpuCabinet.initializeObject(1, 2, 3); hardDisk.initializeObject(1, 2, 3); volumeCPUCabinet = cpuCabinet.volume(); System.out.println("Volume of CPU Cabinet is " + volumeCPUCabinet);

}

}




Java in Hindi bl mnkgj.k esa geus ,d initializeObject uke dk Member Method Create fd;k gSA Object dks Create djus ds ckn gj Object ds fy, gesa bl Method dks Call djds ml Object dks Initialize djuk t:jh gksrk gSA vc blh Program dks ge Constructor ds iz;ksx }kjk fuEukuqlkj Modify dj ldrs gSa& Program class Box { //Attributes double width; double height; double length; //Methods public double volume() { double volume; volume = length * height * width; return volume; }

}

Box() //No-Argument Constructor { System.out.println("No-Argument Constructor Executed"); width =1; length =2; height =3; }

public class ConstructorDemo { public static void main(String args[]) { Box cpuCabinet = new Box(); Box hardDisk = new Box(); double volumeCPUCabinet; double volumeHardDisk; volumeCPUCabinet = cpuCabinet.volume(); System.out.println("Volume of CPU Cabinet is " + volumeCPUCabinet);

}

}


Output


Java in Hindi No-Argument Constructor Executed No-Argument Constructor Executed Volume of CPU Cabinet is 6.0 Volume of Hard Disk is 6.0

bu nksuksa mnkgj.kksa ds Output leku gh gSa tks fd ge ns[k ldrs gSa] ysfdu main() Method esa vUrj gSA igys Program esa ,d initializeObject() Method dks Object ds fy, Call djds Object ds fofHkUu Instance Variables dks Initialize fd;k x;k gS] tcfd nwljs Program esa ;s dke Java Compiler Constructor dk iz;ksx djds Lo;a gh dj ysrk gSA tc ge Box Class dk ,d Object cpuCabinet Create djrs gSa] rks tSls gh Compiler u, Object ds fy, Memory Allocate dj nsrk gS] ml Memory Locations ij fofHkUu Instance Variables ds fy, eku Hkh Initialize gks tkrs gSaA ,slk blfy, gksrk gS] D;ksafd Object ds fy, Memory Allocate gksus ds rqjUr ckn Box Class dk Box uke dk Constructor Method Execute gks tkrk gS vkSj og Method Object ds fofHkUu Instance Variables dks Initialize dj nsrk gSA blh rjg ls tc nwljk Object Create gksrk gS rks nwljs Object dk Hkh igys Constructor Execute gksrk gS vkSj Object ds fofHkUu Dimensions dks Initialize dj nsrk gSA Output esa ge izkIr gksus okyh igyh nks Lines ds vk/kkj ij ge le> ldrs gSa] fd Box Constructor Execute gks jgk gSA tc ge Constructors Define dj jgs gksrs gSa] rc gesa ,d ckr dk /;ku j[kuk pkfg, fd Constructor Method dHkh Hkh dksbZ eku Return ugha djrk gS] blfy, blesa return Statement dk iz;ksx ugha fd;k tkuk pkfg, lkFk gh Return Type dks Hkh Declare ugha fd;k tkuk pkfg,A ;gka rd fd Return Type ds LFkku ij void dk Hkh iz;ksx djus ij Compiler Error iznku djrk gSA lkFk gh ,d Class dk Constructor dsoy mlh Class ds Object ds fy, Execute gksrk gS] blfy, blds lkFk fdlh Access Specifier dk Hkh iz;ksx ugha fd;k tkuk gksrk gSA ;kuh fdlh Class dk Constructor Method Create djrs le; gesa ml Class ds uke dks gh Constructor ds uke ds :i esa Define djuk gksrk gSA blhfy, geus gekjs Program esa dsoy fuEukuqlkj Statement }kjk gh Constructor dks Define fd;k gS] ftlesa fdlh Access Specifier ;k Return Type dk iz;ksx ugha fd;k x;k gS% Box()

//No-Argument Constructor

pwafd] ;s Constructor fdlh izdkj dk dksbZ eku main() Method ls izkIr ugha djrk gS] blfy, blds Parenthesis dks Empty j[kk x;k gSA tc fdlh Constructor dk Parenthesis Empty gksrk gS rks bl izdkj ds Constructor dks No-Argument Constructor dgk tkrk gSA gkykafd ge bl rjg ls Initialization dj ldrs gSa] ysfdu fdlh Object dks Create djrs le; gh ;fn mlds fofHkUu Dimensions dks Set fd;k tk lds] rks T;knk csgrj gksrk gS] D;ksafd ,slk t:jh ugha gksrk gS fd Create gksus okys lHkh Objects ds Attributes ds eku gesa”kk leku gh gksaA ;kuh ge Box Class ls ftrus Hkh CPU Box Object Create djrs gSa] gesa”kk ,slk 264 Any Question or Suggestion, Just Discuss Here...

Java in Hindi gksuk t:jh ugha gksrk gS] fd Create gksus okys gj CPU dh Height, Width o Length leku gksA blfy, ,d gh Class ds dbZ vyx&vyx Size ds Box Objects Create djus ds fy, ge ,slk Constructor Method Define dj ldrs gSa] ftldk iz;ksx djds Create gksus okys gj Object dh Size dks Object Creation ds le; gh Define fd;k tk ldsA bl izdkj ds Constructor dks Parameterized Constructor dgk tkrk gSA pwafd tkok esa ge Methods dh Overloading dj ldrs gSa] blfy, ge Constructors dh Hkh Overloading dj ldrs gSaA ;kuh ge ,d gh uke ds ,d ls vf/kd Constructors dks ,d gh Class esa Define dj ldrs gSaA Program class Box { //Attributes double width; double height; double length; //Methods public double volume() { double volume; volume = length * height * width; return volume; } Box() //No-Argument Constructor { System.out.println("No-Argument Constructor Executed"); width =1; length =2; height =3; }

}

Box(double len, double wid, double hei) { System.out.println("3-Argument Constructor Executed"); width = wid; length = len; height = hei; }

public class ConstructorDemo { public static void main(String args[])


Java in Hindi {

Box cpuCabinet = new Box(); Box hardDisk = new Box(1,2,3); double volumeCPUCabinet; double volumeHardDisk; volumeCPUCabinet = cpuCabinet.volume(); System.out.println("Volume of CPU Cabinet is " + volumeCPUCabinet);

}

}


Output No-Argument Constructor Executed 3-Argument Constructor Executed Volume of CPU Cabinet is 6.0 Volume of Hard Disk is 6.0

bl Program ds Output ls ge le> ldrs gSa fd tc ge cpuCabinet uke dk Box Object Create djrs gSa] rc Box Class dk No-Argument Constructor Execute gksrk gS vkSj tc ge Box Class dk hardDisk Object Create djrs gSa vkSj mlds Constructor esa Dimension ds rhuksa eku Define dj nsrs gSa] rks Compiler hardDisk Object ds fy, 3-Argument Constructor dks Execute djrk gS] tSlkfd ge Output esa ns[k ldrs gSa vkSj hardDisk Object dks Initialized dj nsrk gSA

Arguments Passing

tkok esa fdlh Subroutine (Method) esa Arguments dks Pass djus ds nks rjhds gksrs gSaA igys rjhds dks Pass By Value o nwljs rjhds dks Pass By Reference rjhdk dgk tkrk gSA Pass By Value tc fdlh eku dks Argument ds :i esa Calling Method ls Called Method esa Pass By Value rjhds ls Pass fd;k tkrk gS] rc Calling Method ls vkus okys eku dks izkIr djus ds fy, Called Method esa ,d vkSj Local Variable Create gksrk gSA ;kuh Create gksus okys ml Local Variable esa Calling Method ls vkus okyk eku Copy gks tkrk gSA fQj Called Method esa ml Copied eku ij tks Hkh izfØ;k gksrh gS] mldk izHkko Calling Method ds Variables ds eku ij ugha iMrk gSA bl iwjh izfØ;k dks le>us ds fy, ge ,d mnkgj.k ns[krs gSa] tks fd fuEukuqlkj gSA Program class PassByValue


Java in Hindi {

}

//Attributes //Methods public void calculation( int i, int j) { i = i + 3; j = j + 3; }

public class PBVDemonstration { public static void main(String args[]) { PassByValue object = new PassByValue(); int x=10, y=20; System.out.println("Value of x and y is " + x + " " + y); object.calculation(x, y);

}

}

System.out.println("Value of x and y is " + x + " " + y);

Output Value of x and y is 10 20 Value of x and y is 10 20

bl mnkgj.k Program ds Output ls ge le> ldrs gSa fd x o y ds eku dks calculation() Method esa Pass djus ds ckotwn Hkh x o y dk eku Change ugha gks jgk gSA ,slk blfy, gksrk gS D;ksafd tc x o y dk eku calculation() Method esa Pass fd;k tkrk gS] rc bu Variables ds ekuksa dks Hold djus ds fy, calculation() Method esa i o j uke ds nks Variables Create gksrs gSa vkSj bu Variables esa x o y ds eku Øe”k% Copy gks tkrs gSaA fQj calculation() Method esa tks Hkh Processing gksrh gS og Actual esa i o j ds eku ij gksrh gS] uk fd x o y ds eku ijA blhfy, x o y ds eku esa dksbZ ifjorZu ugha gksrk gSA tc fdlh Method dks bl rjhds ls Call fd;k tkrk gS] ftlesa Actual Argument ds eku dh Copy gh Call gksus okys Method ds Local Variables dks Pass fd;k tkrk gS] rc bl izdkj ds Calling rjhds dks Call By Value ;k Pass By Value rjhdk dgk tkrk gSA Pass By Reference tc Calling Method ls fdlh Method esa bl izdkj ls eku dks Pass fd;k tkrk gS fd ;fn Called Method esa ml eku esa ifjorZu fd;k tk, rks Calling Method esa Hkh ml eku esa ifjorZu gks tkrk gS] rks bl izdkj ls fdlh Method esa eku Pass djus dh izfØ;k dks Pass


Java in Hindi By Reference ;k Call By Reference rjhdk dgk tkrk gSA bls Hkh ge fuEUk mnkgj.k }kjk

le> ldrs gSaA

Program class PassByReference { //Attributes int x, y; //2-Argument Constructor PassByReference(int i, int j) { x = i; y = j; }

}

//Methods public void calculation( PassByReference temp ) { temp.x = temp.x + 3; temp.y = temp.y + 3; }

public class PBRDemonstration { public static void main(String args[]) { PassByReference object = new PassByReference(10, 20); System.out.println("Value of object.x and object.y before call is : " + object.x + " " + object.y); object.calculation(object);

}

}

System.out.println("Value of object.x and object.y after call is : " + object.x + " " + object.y);

Output Value of object.x and object.y before call is : 10 20 Value of object.x and object.y after call is : 13 23

bl mnkgj.k esa ge ns[k ldrs gSa fd tc Object dks calculation() Method esa Hkstk tkrk gS] rc Object ds eku esa Method ds ifjorZuksa dk izHkko iMrk gS vkSj Object ds Attributes ds ekuksa esa Hkh ifjorZu gks tkrk gSA bl rjg ls tc fdlh Object dks fdlh Method esa Pass fd;k tkrk gS] rks bls Pass By Reference ;k Call By Reference rjhdk dgk tkrk gSA


Java in Hindi lkekU;r;k ,d ckr /;ku j[kuh pkfg, fd tkok esa tc fdlh Method esa fdlh Basic Data Type ds eku dks Argument ds :i esa Pass fd;k tkrk gS] rc bl rjg Call gksus okyk Method “By Value” Call gksrk gS vkSj tc fdlh Object dks fdlh Method esa Argument ds :i esa Pass fd;k tkrk gS] rc Call gksus okyk Method “By Reference” Call gksrk gSA ,slk blfy, gksrk gS D;ksafd tc ge fdlh Class dk dksbZ Variable Create dj jgs gksrs gSa rc tkok esa Actual Object Create ugha gksrk gS] cfYd Object dk ,d Reference ek= gh Create gksrk gS] tks fd mlh Actual Physical Memory Block dks Refer dj jgk gksrk gS] ftls Calling Method dk Object Refer dj jgk gksrk gSA

Access Controls

Access Control dk iz;ksx djds ge ;s r; dj ldrs gSa fd Program dk dkSulk Hkkx fdlh Class ds Members dks Access dj ldrk gSA Access Controls dk iz;ksx djds ge Class ds Members dks xyr rjhds ls Use djus ls jksd ldrs gSaA

mnkgj.k ds fy, ;fn ge Class ds Data dks fdlh Well Defined Method }kjk gh Access djus ds fy, Control djuk pkgsa] rks blds fy, ge Access Controls dk iz;ksx dj ldrs gSaA ftlls fdlh Hkh vU; rjhds ls Class ds Data dks Access ugha fd;k tk ldsA ,sls esa ge Class ds Data dks ;fn Access djuk pkgsa rks ge Class es ml Data dks Access djus okyk Method Define dj nsrs gSaA ,slk djus ij ge dsoy ml Method }kjk gh Class ds Data dks Access dj ldrs gSaA Class ds Data dks Access djus dk dksbZ vkSj nwljk rjhdk ugha gksrk gSA ;fn gesa Class ds fdlh Data dks Access djuk gS] rks gesa ml Class ds mlh Method dks Use djuk gksxk] tks ml Data dks Access dj ldrk gSA Encapsulation dk eq[; mn~ns”; ;gh gS fd ge Class ds Data dks mlh Class ds fdlh Member }kjk gh Access djus esa l{ke gksaA ,slk gksus ij Class ds Data lqjf{kr jgrs gSa vkSj fdlh Hkh vU; rjhds ls Class ds Data dks modify ugha fd;k tk ldrk gSA vHkh rd geus ftruh Hkh Classes cukbZ gSa] mu lHkh Classes ds Data dks fdlh Hkh Method esa Directly Access fd;k tk ldrk gSA blfy, bu Classes dks ge ,slh Class ugha dg ldrs gSa tks Encapsulation ds fu;e dks Follow djrs gksaA

fdlh Class ds Members dks fdl izdkj ls Access fd;k tk ldrk gS ;s r; djus ds fy, ge Access Specifier dk iz;ksx djrs gSaA tkok esa Access Specifier dk ,d lewg gS] tks ;s r; djrs gSa fd fdl fLFkfr esa fdlh Member dks fdl gn rd Access fd;k tk ldrk gSA buesa ls dqN Access Specifier eq[;r;k Inheritance o Packages ds fy, gh Use gksrs gSaA fdlh ,d fo’k; ls lEcaf/kr lHkh Classes ds ,d lewg dks Package dgk tkrk gSA Package ls lEcaf/kr Access Specifier ds ckjs esa ge vkxs foLrkj ls ppkZ djsaxsA ;gka ge dsoy ,d Single Class ls lEcaf/kr Access Specifier ds ckjs esa lh[ksaxsA tkok ds eq[; Access Specifier public, protected o private gSaA lkFk gh tkok dk ,d Default Access Specifier Hkh gSA protected Specifier dsoy rc Apply gksrk gS] tc Inheritance dk iz;ksx fd;k tkrk gSA


Java in Hindi public and private Access Specifier tc fdlh Class ds Members public gksrs gSa] rc Class ds mu Members dks fdlh Hkh vU; Method }kjk Directly Access djds Modify fd;k tk ldrk gSA ysfdu tc fdlh Class ds Members private gksrs gSa] rc Class ds mu Members dks dsoy mlh Class esa Define fd, x, public Methods }kjk gh Access fd;k tk ldrk gSA main() Method dks ge blhfy, gesa”kk public j[krs gSa] rkfd main() Method dh Class ds fofHkUu Data dks vklkuh ls main() Method o fdlh Hkh vU; Method }kjk Access fd;k tk ldsA tc fdlh Class fdUgha Member ds lkFk fdlh Access Specifier dk iz;ksx ugha fd;k tkrk gS] rc Class ds os Members Default :i ls public gksrs gSaA tSlkfd geus Box Class esa fdlh Hkh Data Member ds lkFk fdlh Access Specifier dk iz;ksx ugha fd;k gS] blfy, ;s lHkh Data Members Default :i ls public gSaA ,d ckr /;ku j[kus okyh ;s gS fd tc ge fdlh Class ds Members ds lkFk fdlh Access Specifier dk iz;ksx ugha djrs gSa] rc ml Class ds Members dks ge dsoy mlh Package esa Directly Access dj ldrs gSaA Default Access Control dh Range dsoy mlh Package rd gksrh gSA ;fn gesa fdlh ,d Package ds Class ds Members dks fdlh nwljs Package ds Members esa Use djuk gS] rks ges igys Package ds Members dks public Access Specifier ds lkFk gh Declare

djuk t:jh gksrk gSA

vHkh rd geus tks Hkh Class Develop dh gS] mlesa lHkh Data Members Default :i ls public gSaA mnkgj.k ds fy, Box Class ds lHkh Members public gSa] blhfy, ge main() Method ls Hkh Box Class ds Data dks eku iznku dj ldrs gSa vkSj Box Class ds Data ds ekuksa dks Screen ij Print dj ldrs gSaA tcfd okLro esa ,slk ugha gksuk pkfg,A ;fn ge Default Access Specifier dk iz;ksx djrs gSa] rks Program ds fdlh Hkh Method }kjk Box Class ds Object ds Data dks Modify fd;k tk ldrk gS] tks fd ugha gksuk pkfg,A D;ksafd fdlh Hkh Practical Application esa lcls t:jh pht Data dh Security gh gksrh gSA blfy, gesa gesa”kk viuh Class ds Data dks fdlh Hkh vU; Method }kjk Modify gksus ls jksduk gksrk gSA ;s dke ge rc dj ldrs gSa tc Class ds Data Members private gksaA fdlh Class ds Object Program ds vU; fgLlksa ls rHkh Communicate dj ldrs gSa] tc ml Class dk dksbZ Member public gksrk gSA Data dh lqj{kk ds dkj.k ge Data dks rks public ugha dj ldrs gSa] ysfdu Class ds Methods dks ge public j[krs gSaA Class ds Methods gh Program ds vU; fgLlksa esa Class ds Data dks Access djus dk ,d ek= ek/;e gks ldrs gSa] D;ksafd os public gksrs gSaA pfy,] bl izfØ;k dks ,d Program }kjk le>rs gSa ftlesa geus fQj ls Box Class dk gh mnkgj.k fy;k gSA pwafd ge pkgrs gSa fd Box Class ds Data dks fdlh Hkh vU; Method }kjk Directly Access uk fd;k tk lds] blfy, gesa Box Class ds Data dks private djuk gksxkA ;s dke ge fuEukuqlkj dj ldrs gSa% class Box { private double width; private double height; private double length;


Java in Hindi }

vc bl Class dks Access djus ds fy, ge fuEukuqlkj ,d Program cuk ldrs gSa& Program class Box { //Attributes private double width; private double height; private double length;

}


public class BoxVolume { public static void main(String args[]) { Box cpuCabinet = new Box(); Box hardDisk = new Box(); cpuCabinet.length = 100; cpuCabinet.height = 70; cpuCabinet.width = 20; hardDisk.length = 10; hardDisk.height = 1.5; hardDisk.width = 6;

}

}


;fn bl Program dks ge Compile djrs gSa] rks gesa fuEukuqlkj Errors izkIr gksrs gSa% Output PrivateDataMember.java:25: length has private access in Box cpuCabinet.length = 100; ^ PrivateDataMember.java:26: height has private access in Box


Java in Hindi cpuCabinet.height = 70; ^ PrivateDataMember.java:27: width has private access in Box cpuCabinet.width = 20; ^ PrivateDataMember.java:29: length has private access in Box hardDisk.length = 10; ^ PrivateDataMember.java:30: height has private access in Box hardDisk.height = 1.5; ^ PrivateDataMember.java:31: width has private access in Box hardDisk.width = 6; ^ 6 errors

;s Errors blfy, Generate gksrs gSa] D;ksafd Box Class ds Data Members dks private Declare fd;k x;k gS vkSj fdlh Class ds Private Data Members dks mlh Class dk dksbZ public Method gh Access dj ldrk gSA pwafd gesa Box Class ds Objects dks Initialize djuk gS rks ;k rks ge bl dke ds fy, Constructors dk iz;ksx dj ldrs gSa] D;ksafd Constructors mlh Class ds os Methods gksrs gSa] tks Object Creation ds lkFk gh Automatically Execute gks tkrs gSa] ;k fQj ge Box Class esa fuEukuqlkj ,d public Method Define djds Box Object dks Initialize dj ldrs gSa%

public void initializeObject(double len, double wid, double hei) { length = len; width = wid; height = hei; }

bl Method dks viuh Box Class esa fuEukuqlkj Include djds ge main() Method esa Box Class ds Object ds Data dks Box Class ds Outside ds main() Method esa Access dj ldrs gSa% Program class Box { //Attributes private double width; private double height; private double length; //Methods public void volume() { double volume; volume = length * height * width;


Java in Hindi

}

System.out.println("Volume is " + volume); } public void initializeObject(double len, double wid, double hei) { length = len; width = wid; height = hei; }

public class PrivateDataPublicMethod { public static void main(String args[]) { Box cpuCabinet = new Box(); Box hardDisk = new Box(); cpuCabinet.initializeObject(100, 70, 20); hardDisk.initializeObject(10, 1.5, 6);

}

}


Output Volume is 140000.0 Volume is 90.0

;s Program Compile Hkh gksrk gS vkSj Execute gks dj Result Hkh iznku djrk gSA fdlh Class ds Private Members dks ml Class ls ckgj fdlh nwljh Class esa Use djus ds fy, gesa gesa”kk blh rjhds dks Use djuk iMrk gSA ftl rjg ls ge public o private Data Members Create dj ldrs gSa] mlh rjg ls ge fdlh Class esa private Methods Hkh Create dj ldrs gSaA ysfdu ,slk djus ij ;fn ge ml private Method dks Class ls Outside esa Use djuk pkgsa] rks Hkh gesa mlh Class ds ,d public Method dh t:jr gksrh gSA lkjka”k ;s gS fd fdlh Class ds private Members dks ml Class ls ckgj fdlh vU; Class esa rHkh Use fd;k tk ldrk gS] tc mlh Class esa fdlh public Method esa private Members dks Access djus ds Code fy[ks x, gksaA fdlh Class ds private Members dks Class ls ckgj Access djus dk dksbZ vkSj nwljk rjhdk ugha gSA

static Data Members and Methods

dbZ ckj fdlh Class esa gesa ,sls Data Members Define djus dh t:jr gksrh gS] ftudk ml Class ds Object ds Conjunction ds lkFk iz;ksx ugha gksrk cfYd bu Data Members dks Lora= :i ls Access fd;k tk ldrk gSA mnkgj.k ds fy, ekuyks fd gesa ;s tkuuk gks fd


Java in Hindi fdlh Program esa Class ds fdlh le; ij dqy fdrus Objects Create gq, gSa] rks ;s dke iwjk djus ds fy, gesa Class esa ,d static Data Member dks Define djus dh t:jr iMrh gSA lkekU;r;k fdlh Class ds ftrus Hkh Data Members gksrs gSa] mUgsa mlh Class ds fdlh Object ds Conjunction ds lkFk gh Access fd;k tkrk gSA ysfdu Class esa ,sls Data Member Hkh Create fd, tk ldrs gSa] ftudks fcuk fdlh Object ds Reference ds Hkh Directly Access o Use fd;k tk ldrk gSA bl izdkj ds Members Create djus ds fy, gesa Data Member ds lkFk static Keyword dk iz;ksx djuk iMrk gSA fdlh Class ds ,d static izdkj ds Data Member dks fcuk ml Class ds fdlh Object dks Create fd, gq, Hkh Directly Access dj ldrs gSA blh fy, main() Method dks static j[kk tkrk gS] D;ksafd ,d static Method dks ftl Class esa Declare fd;k tkrk gS] ml Class ds fdlh Object dks Create djus ls igys Hkh ml Class ds bl static Method dks Call fd;k tk ldrk gSA fdlh Class ds ftu Instance Variables dks static Declare fd;k tkrk gS] os lkekU;r;k Global Variables gksrs gSa] blfy, tc ml Class ds Object Create fd, tkrs gSa] rc gj Object ds fy, lHkh Non-Static Data Members dh Copy rks Create gksrh gS] ysfdu static Data Members dh Copy Create ugha gksrh gSA ;kuh ml iwjh Class ds lHkh Objects ds fy, static Data Member Common :i ls Use gksrk gS vkSj ml Class ds lHkh Objects static Data Member dks leku :i ls Share djrs gSaA static Methods dqN fuf”pr fu;eksa dk ikyu djrs gSaA 1

fdlh Class ds Static Methods dks dksbZ static izdkj dk Method gh Call dj ldrk gSA 2 static Methods fdlh static Data Members dks gh Access dj ldrs gSaA 3 ;s Methods this o super dk iz;ksx fdlh izdkj ls ugha dj ldrs gSaA super Keyword ds ckjs ge Inheritance Chapter ds vUrxZr vPNh rjg ls le>saxsA ;fn fdlh static Variable dks Initialize djuk gks] rks gesa ,d static Block Declare djuk iMrk gSA tc Class Memory esa igyh ckj Load gksrh gS] rc ;s Block ,d vkSj flQZ ,d gh ckj Execute gksrk gSA bls le>us ds fy, ge ,d mnkgj.k ns[krs gSaA Program //static variable, methods and blocks Demonstration. class StaticDemonstration { static int x = 3; static int y; static void calculation(int i) { System.out.println(“i = “ + i); System.out.println(“x = “ + x); System.out.println(“y = “ + y); }


Java in Hindi static { System.out.println(“Static block being Initialized.“); y = x * 3; }

}

public static void main(String args[]) { calculation(10); }

Output Static block being Initialized. i = 10 x=3 y=9

bl Program dks tSls gh Compile djds Run fd;k tkrk gS] rks StaticDemonstration Memory esa Load gks tkrk gS] blds lHkh static Statements Execute gks tkrs gSaA lcls igys x dk eku 3 Initialize gksrk gSA fQj static Block Execute gksrk gS vkSj vUr esa y dk eku Initialize gksrk gSA fQj main() Method Call gksrk gS vkSj calculation() Method esa iznku fd;k tkus okyk eku 10 Variable i dks izkIr gks tkrk gSA bl Method esa rhu println() Statements gSa tks nks static Variables x o y rFkk ,d Local Variable i ds eku dks Screen ij Print djus dk dke djrs gSaA Class esa Define fd, x, static Variables o Methods dks ml Class ls Outside esa Hkh Lora= :i ls Use fd;k tk ldrk gSA fdlh static Variable ;k Method dks Class ls ckgj Lora= :i ls Use djus ds fy, gesa bl izdkj ds Variables o Methods dks Dot Operator ds lkFk Use djuk gksrk gSA tSls ;fn ge fdlh static Method dks Program ds fdlh fgLls esa mldh Class ls Outside esa Call djuk pkgrs gSa] rks ;s dke ge fuEukuqlkj Form esa dj

ldrs gSa%

Classname.method();

;gka Classname og Class gS ftlesa static Method dks Declare fd;k x;k gSA ge ns[k ldrs gSa fd ;s Format mlh rjg dk gS ftl rjg ds Format dk iz;ksx djds ge fdlh Object ds fy, fdlh Non-Static Method dks Call djrs gSaA fdlh static Variable dks Hkh blh rjg ls Use fd;k tk ldrk gS ysfdu Object ds uke ds LFkku ij Class dk uke Use djuk gksrk gSA fuEu mnkgj.k esa bl iwjs Process dks Use fd;k x;k gSA Program //static variable, methods and blocks Demonstration. class StaticClass { static int x = 3; static int y = 21;


Java in Hindi

}

static void calculation() { System.out.println("x = " + x); }

class StaticDemo { public static void main(String args[]) { StaticClass.calculation(); System.out.println("y = " + StaticClass.y); } } Output x=3 y = 21

final Keyword

dbZ ckj gesa ,sls ekuksa dh t:jr gksrh gS] tks iwjs Program esa dsoy ,d gh ckj Initialized fd;k tkrs gSa vkSj iwjs Program esa ;s eku Constant jgrs gSaA tc gesa bl izdkj ds Instance Variable Declare djus gksrs gSa] rc ge bl izdkj ds Variables dks final Keyword ds lkFk Declare djrs gSaA bl rjg ds Variables dks Declare djrs gh bUgsa Initialize djuk gksrk gSA tSls final String NAME = “Gopal”; final int ROLLNUMBER = 12121212; final double DIMENSION = 1.0;

ftu Variables dk eku final Keyword ds lkFk Declare fd;k x;k gksrk gS] mu Variables ds ekuksa dks ge iwjs Program esa dgha Hkh Change ugha dj ldrs gSaA ;fn ge bUgsa Change djus dh dksf”k”k djrs gSa] rks tkok dk Compiler gesa Error nsrk gS vkSj Program Compile ugha gksrk gSA lkekU;r;k ftu Variables dks gesa final Declare djuk gksrk gS] mUgsa Capital Letters ds iz;ksx }kjk Declare fd;k tkrk gSA gkykafd ge bls Small Letters dk iz;ksx djds Hkh Declare dj ldrs gSaA ge Variables dh rjg Methods dks Hkh final Declare dj ldrs gSa] ysfdu blds ckjs esa ge vkxs le>saxsA

Nested and Inner Classes

ftl rjg ls ge fofHkUu izdkj ds Control Statements dh Nesting dj ldrs gSa mlh rjg ls ge fdlh ,d Class esa nwljh Class dks Hkh Nest dj ldrs gSaA Nested Class dsoy ml Class rd gh miyC/k gksrk gS] ftlesa bls Create fd;k tkrk gSA


Java in Hindi fdlh Nested Class ds Objects dks ge ml Class ls ckgj Create ugha dj ldrs gSa] ftlesa ;s Class Nested gSaA ;kuh ;fn ,d Class B dks Class A esa Define fd;k x;k gS] rks Class B ds ckjs esa Class A dks irk gksrk gS] ysfdu Class B ds ckjs esa Class A ds vykok Program ds fdlh fgLls dks irk ugha gksrk gSA ,d Nested Class dks fdlh Hkh rjhds ls mldh Outer Class ds vykok dgha Hkh Access ugha fd;k tk ldrk gSA ,d Nested Class mldh Outer Class ds fdlh Hkh Member dks Access dj ldrk gS ysfdu Outer Class Inner Class ds fdlh Hkh Member dks Access ugha dj ldrk gSA Nested Class Hkh nks rjg dh gks ldrh gSA igys izdkj dh Class static Class gksrh gSA bl izdkj dh Class esa static Modifier dk iz;ksx fd;k x;k gksrk gSA pwafd ;s ,d static Class gksrh gSA blfy, ;g vius Outer Class ds Members dks ,d Object ds Reference }kjk Access dj ldrk gSA ;kuh ,d static Inner Class viuh Outer Class ds Members dks fcuk vius Object ds Access ugha dj ldrk gSA lkekU;r;k bl izdkj dh Class dks Use

ugha fd;k tkrk gSA

nwljh izdkj dh Class ,d Inner Class gksrh gSA ;s ,d Non-Static Nested Class gksrk gS vkSj vius Outer Class ds lHkh Members dks Directly Access dj ldrk gSA fuEu Program }kjk ge bl Class ds Concept dks le> ldrs gSa tgka Outer ,d Outer Class gS vkSj Inner ,d Inner Class gSA Program class Outer { int outerVariable = 100; void Test() { Inner inner = new Inner(); inner.display(); } class Inner { void display() { System.out.println(“Display : outerVariable = “ + outerVariable); } } } class InnerClassDemonstractoin { public static void main(String args[]) { Outer outer = new Outer(); outer.Test(); } }


Java in Hindi Output Display : outerVariable = 100

bl Program esa Inner Class dks Outer Class ds vUnj Nested fd;k x;k gSA blfy, Inner Class Directly outerVariable dks Access dj ldrk gSA Inner Class esa ,d Instance Method display() Define fd;k x;k gSA ;s Method outerVariable ds eku dks Display djus dk dke djrk gSA main() Method Outer Class dk ,d Object Create djrk gS vkSj blds Test() Method dks Call djrk gSA ;s Method Inner Class dk ,d Object Create djrk gS vkSj display() Method dks Call djrk gSA ;s ckr /;ku nsus okyh gS fd Inner Class dks dsoy Outer Class esa gh Use fd;k tk ldrk gSA Outer Class ds Scope ls ckgj ;fn bl Class dk Instance Create djuk pkgsa] rks ge ,slk ugha dj ldrs gSaA Compiler gesa ,slk ugha djus nsrk gSA ,d Inner Class viuh Outer Class ds lHkh Members dks Directly Access dj ldrk gSA ysfdu ,d Outer Class viuh Inner Class ds fdlh Hkh Member dks Directly Access ugha dj ldrkA Inner Class ds Members dks dsoy Inner Class esa gh Access fd;k tk ldrk gSA ;fn ge ,d Outer Class esa Inner Class dks Use djus dh dksf”k”k djrs gSa] rks tkok Compiler gesa ,slk ugha djus nsrk gSA

GUI Application Of Java

fiNys v/;k; rd geus fofHkUu izdkj ds GUI Applets cuk, gSa] tks fofHkUu izdkj ds dke djus esa l{ke gSaA ysfdu Applets gesa”kk HTML Web Page ds vUnj Run gksrs gSa] blfy, ;s iwjh rjg ls gekjs local Computer ds lHkh Resources dks Use djus esa l{ke ugha gksrs gSaA lkFk gh Window ds Frame ds :i esa ;s HTML Window dks Use djrs gSaA ftl rjg ls geus vHkh rd GUI Applets Create fd, gSa] mlh rjg ls ge GUI Applications Hkh Create dj ldrs gSaA tc ge Applet Create djrs gSa] rc gesa By Default ,d Window izkIr gks tkrk gSA D;ksafd ;s Window HTML Web Page gksrk gSA ysfdu tc gesa Standalone Application cukuk gksrk gS] rc ,d Basic Window Create djus dk dke Hkh gekjk gh gksrk gSA tSlkfd ge tkurs gSa fd Applet Class Panel Class dh Sub Class gS vkSj Panel Class rFkk Window Class nksuksa gh Component Class dh Sub Classes gSaA ;kuh Panel Class o Window Class nksuksa gh Sibling Classes gSa] ftldh otg ls tks xq.k ,d Panel esa gksrs gSa] yxHkx os lHkh xq.k Window esa Hkh gksrs gSaA ftl rjg ls Panel Class dk Object Screen ij fn[kkbZ ugha nsrk gS] mlh rjg ls Window Class dk Object Hkh Screen ij fn[kkbZ ugha nsrk gSA Screen ij fn[kkbZ nsus dk xq.k Panel Class dh Sub Class Applet esa gksrk gSA Bhd blh rjg ls Window Class dh Sub Class Frame o Dialog esa Hkh Screen ij fn[kkbZ nsus dk xq.k gksrk gSA gkykafd Applet Class o Frame Class nksuksa gh Classes ds Objects Screen ij fn[kkbZ nsrs gSa] ysfdu nksuksa esa ,d Basic vUrj ;s gSa fd Applet Class


Java in Hindi dk Object fdlh uk fdlh Web Page esa gh fn[kkbZ nsrk gS] tcfd Frame Class ;k Dialog Class dk Object Standalone Hkh Display gks ldrk gSA blfy, tc gesa tkok Programming Language dk iz;ksx djrs gq, Standalone GUI Application Develop djuk gksrk gS] rc Container ds :i esa Frame Class dk Object Create djuk iMrk gSA Frame Class gesa ,d Standalone GUI Window iznku djrk gS] ftlesa ,d Title Bar, Control Toolbox o Border gksrk gSA pwafd fdlh Hkh Applet Program esa dksbZ main() Method ugha gksrk gS] blfy, ;fn ge pkgsa rks fdlh Hkh Applet Program dks Application Program esa Convert dj ldrs gSaA

Java Application – The Frame Class Frame Class dk Object ,d Resizable Window iznku djrk gS] tks Menu Bar Cursor, Icon o Title dks Support djrk gSA Frame dk iz;ksx dsoy tkok ds Applet Window o Application esa gh fd;k tk ldrk gSA pwafd ;s Container Class ls Derived gksrk gS] blfy, ge blesa vU; Controls dks Place dj ldrs gSaA tc gesa tkok Application Create djuk gksrk gS] rc GUI Window Create djus ds fy, ge bl Class dk Object Create djrs gSaA Frame dk iz;ksx ge fdlh HTML Page ds fofHkUu Contents dks Frames esa Setup djus ds fy, Hkh dj ldrs gSaA ,d izdkj ls ;s gekjk Basic Application Type Window gksrk gS] tks ,d ,slk Window gksrk gS] ftls ge T;knkrj Programs esa ns[krs gSaA ge Frames dk iz;ksx Applets esa Hkh dj ldrs gSaA lkekU;r;k tc gesa fdlh Applet esa Menu Bar ;k Dialog Box dks Use djuk gksrk gS] rc gesa Frames dk iz;ksx djuk t:jh gks tkrk gSA D;ksafd fcuk Frames dk iz;ksx fd, gq, ge fdlh Applet esa Menu Bar ;k Dialog Box dk iz;ksx ugha dj ldrs gSaA ,d Frame Hkh ogh Events Generate djrk gS] tks ,d Window Object Generate djrk gSA ;kuh WINDOW_DESTROY, WINDOW_ICONIFY, WINDOW_DEICONIFY, and WINDOW_MOVED Frame Constructor dks ge dsoy ,d gh String Parameter Pass djrs gSa vkSj ;s String Parameter Frame Window dk Title gksrk gSA ge lkekU;r;k gekjh Lo;a dh Class Create djrs gSa vkSj ml Class dks Frame Class ls Extend djrs gSa ;k gekjh Loa; dh Class esa Frame dh Class ds xq.kksa dks Inherit djrs gSaA

lkFk gh fofHkUu izdkj ds Components ds Events dks Hkh Handle djrs gSaA fofHkUu izdkj ds Events dks Handle djus ds fy, ge fofHkUu Components dh Event Handling Methods dks Override djrs gSaA Frame Window Create djus ds fy, lcls igys gesa ,d Class Create djuh gksrh gS vkSj ml Class esa main() Method Create djuk gksrk gSA fQj main() Method esa Frame Class dk ,d Object Create djuk gksrk gS vkSj ml Object ds Constructor esa Argument ds :i esa Frame Window dk uke nsuk gksrk gSA ge fuEukuqlkj Statement }kjk ,d Frame Object Create dj ldrs gSa%


Java in Hindi Frame firstApplicationWindow = new Frame(“Frame Window”);

bl Statement }kjk ,d Frame Object Create gksrk gSA ysfdu vHkh rd ;s Object dsoy Memory esa gh Create gqvk gSA dsoy blh Statement }kjk ge Created Window dks ugha ns[k ldrs gSaA Frame Window fn[kkbZ ns] blds fy, gesa Frame Object dks Visible djuk gksrk gSA Frame Window dks Visible djus ds fy, gesa setVisible() Method dk iz;ksx djuk iMrk gSA bl Method esa gesa Argument ds :i esa ,d Boolean eku nsuk gksrk gS] tks ;s r; djrk gS fd Window dks Show djuk gS ;k Hide djuk gSA bl Method dks Component Class ls Derive fd;k x;k gS] blfy, bl method dks ge fdlh Hkh Control Component ds lkFk Use dj ldrs gSaA pwafd gesa gekjs Frame Window dks Screen ij Display djuk gS] blfy, gesa Frame Window Object ds lkFk bl method dks fuEukuqlkj Call djuk iMrk gS% firstApplicationWindow.setVisible(true) Frame Window dks Visible dj nsus ij Window Screen ij Visible rks gks tkrk gS] ysfdu gesa fuEukuqlkj Window dk dsoy Title Bar gh fn[kkbZ nsrk gSA

Frame Window fdruk yEck&pkSMk fn[kkbZ nsuk pkfg,] ;s Hkh gesa gh r; djuk gksrk gSA Frame Window dh Height o Width r; djus ds fy, gesa Component Class ds setSize() Method dk iz;ksx djuk gksrk gSA

bl Method dks Component Class ds fdlh Hkh Method dh Height o Width Set djus ds fy, Use fd;k tkrk gSA bl Method esa gesa nks Arguments iznku djus gksrs gSaA bl Method dk igyk Argument Width dks Specify djrk gS] tcfd nwljk Argument Frame Window dh Height dks Represent djrk gSA bl Method dks Frame Object ds lkFk esa fuEukuqlkj Use djds Frame Window dh Size dks r; fd;k tkrk gS% firstApplicationWindow.setSize(300, 200);

vc fn[kkbZ nsus okyk Frame Window gesa fuEukuqlkj fn[kkbZ nsrk gS%

pwafd fn[kkbZ nsus okys Window dk Background White Color dk gS] blfy, ;fn ge pkgsa rks Window ds Background dks setBackground() Method dk iz;ksx djds Change dj ldrs gSaA ekuyks fd gesa Window ds Color dk Background pkfg,] rks blds fy, ge


Java in Hindi fuEukuqlkj Statement dk iz;ksx djds Frame Window ds Background dks Change dj ldrs gSa% firstApplicationWindow.setBackground(new Color(233, 233, 209));

bl Statement dks vius Program esa Use djus ij gesa fuEukuqlkj Frame Window izkIr gksrk gS%

bl izdkj dk Window Create djus ds fy, gesa fuEukuqlkj Application Program fy[kuk gksrk gS% Program // File: MyFirstApplicationWindow.java import java.awt.*; class MyFirstApplicationWindow { public static void main(String args[]) { Frame firstApplicationWindow = new Frame("Frame Window"); firstApplicationWindow.setVisible(true); firstApplicationWindow.setSize(300, 150); firstApplicationWindow.setBackground(new Color(233, 233, 209)); } }

;s ,d Application Program gS vkSj bls Run djus ds fy, gesa dksbZ Hkh HTML File ugha cukuh iMrh gSA ysfdu ;s Program Standalone Run gksrk gSA bls fdlh Web Page esa Run ugha fd;k tk ldrk gSA ;fn ge fdlh Applet dks Application esa Convert djuk pkgsa] rks cgqr gh vklkuh ls ;s dke fd;k tk ldrk gSA ekuyks fd fiNys v/;k; ds ModifiedThreeControlApplet Program dks gesa bl Frame Application esa Convert djuk gSA bl dke dks djus ds fy, gesa dsoy ModifiedThreeControlApplet Class dk ,d Object Create djuk gksxk] vkSj mlds init() Method dks Call djds Applet dks Initialize djuk gksxkA fQj add() Method dk iz;ksx djds Frame Window esa ModifiedThreeControlApplet Object dks Add djuk gksxkA ,slk


Java in Hindi djus ij ,d ModifiedThreeControlApplet Program ,d Application dh rjg dke djus yxrk gSA bl iwjh izfØ;k dks ge fuEukuqlkj Program }kjk le> ldrs gSa% Program // File: MyFirstApplicationWindow.java import java.awt.*; public class MyFirstApplicationWindow { public static void main(String args[]) { Frame firstApplicationWindow = new Frame("Frame Window"); ModifiedThreeControlApplet appletToApplication; appletToApplication = new ModifiedThreeControlApplet(); appletToApplication.init(); firstApplicationWindow.add("Center", appletToApplication);

}

}

firstApplicationWindow.setSize(400, 200); firstApplicationWindow.setVisible(true); firstApplicationWindow.setBackground(new Color(233, 233, 209));

Output

blh rjhds ls ge fofHkUu izdkj ds vU; Applets dks Hkh Application esa Convert dj ldrs gSaA bl Program esa geus ModifiedThreeControlApplet Class dk ,d Object appletToApplication Create fd;k gSA gkykafd ;s Class geus bl Program esa Create ugha dh gSA ysfdu fQj Hkh ge bl Class dk Object nwljs Program esa dj jgs gSaA ,slk blfy, lEHko gS] D;ksafd ModifiedThreeControlApplet Program dh Class File o MyFirstApplicationWindow Program dh Class File nksuksa gh Class Files leku Folder esa Saved gSaA blfy, ge ,d Program ds Class dks nwljs Program esa Use dj ldrs gSaA


Java in Hindi pwafd Applet Class ls Derive fd, x, ModifiedThreeControlApplet Class esa dksbZ main() Method ugha gSa] blfy, ;s Derived Class Hkh] fdlh vU; lkekU; Class dh rjg gh ,d lkekU; Class gSA vr% ge bl Class dk Object Hkh Create dj ldrs gSaA gekjs bl Program esa geus ;gh fd;k gSA bl Derived Applet Class dk ,d Object appletToApplication Create fd;k gS vkSj bls Initialize djus ds fy, mlh Applet Class ds init() Method dks Call fd;k gSA tc Applet Initialize gks tkrk gS] rc bl ModifiedThreeControlApplet Class ds appletToApplication Object dks Frame Object esa add() Method dk iz;ksx djds Add dj fy;k gSA ,slk djus ls Applet Class dk Object Frame Object esa Place gks tkrk gS vkSj gekjk Applet ,d Application dh rjg dke djus yxrk gSA blh Application Program }kjk ge fdlh Hkh Applet dks Application esa Convert dj ldrs gSaA


Java in Hindi

Java Inheritance For

Code Reusability


Java in Hindi Java Inheritance – Code Reusability

OOP esa Inheritance Class ds ckn nwljk lcls cMk Center Concept gSA Inheritance Reusability dks lEHko cukrk gSA bldh otg ls ge ,d gh Class dks ckj&ckj vyx&vyx fLFkfr;ksa esa mi;ksx esa ys ldrs gSa vkSj gesa ckj&ckj ,d gh izdkj ds Code ugha fy[kus iMrs gSaA

Reusability

gesa”kk gj Program esa dqN dke ,sls gksrs gSa ftUgsa FkksMk cgqr ifjorZu ds lkFk djuk gh iMrk gSA mnkgj.k ds fy, vkt ge GUI okrkoj.k ds Program fy[krs gSaA bu lHkh Programs esa fdlh uk fdlh gn rd dqN Menus, dqN Standard Tool Buttons, dqN Window ;k Forms vkfn yxHkx lHkh Programs esa leku gksrs gSaA OOPS ls igys gj Program ds fy, gj Source File esa budh Coding dks fy[kuk iMrk Fkk tks yxHkx lHkh Source File esa leku gksrs FksA blds fy, T;knkrj ckj fdlh fiNys Program dh Coding dks Copy djds u, Program dh Source File esa Paste fd;k tkrk FkkA viuh vko”;drkuqlkj Source Coding esa ifjorZu fd;k tkrk Fkk vkSj Program dks fQj ls Compile djds mi;ksx esa ys fy;k tkrk FkkA

ysfdu vDlj gksrk ;s Fkk fd tc iqjkus Program dh Coding dks u, Program esa Copy fd;k tkrk Fkk rks vko”;drkuqlkj fofHkUu ifjorZu djus ij Program esa okil Bugs vk tkrs Fks ftUgsa fQj ls Debug djuk iMrk FkkA dbZ ckj rks Bugs fudkyus esa bruk le; yx tkrk Fkk fd Programmer dks yxrk Fkk fd ;fn mlus iwjh Coding gh fQj ls dj yh gksrh] rks Hkh mruk le; ugha yxrk ftruk iqjkuh Coding dks Debug djus esa yx jgk gSA ;kuh iqjkuh Coding dks Use djuk ,d cMh leL;k ds leku Fkk vkSj Programmers gesa”kk ;s pkgrs Fks fd mUgsa ,d gh izdkj dh Coding ckj&ckj uk djuh iMsA Program ds Bugs dks Reduce djus o iqjkuh Coding dks Use djus ds fy, Programmers Functions Create djus yxsA Functions dh ;s fo”ks’krk gksrh gS fd bUgsa ,d gh ckj Debug

djds dbZ ckj mi;ksx esa fy;k tk ldrk gSA fofHkUu izdkj ds dkeksa ds fy, fofHkUu izdkj ds Functions fy[ks tkrs Fks vkSj mUgsa ,d Bundle ds :i esa Reuse djus ds fy, Functions dh Library cuk yh tkrh FkhA bUgha Functions dh Library dks “C” Hkk’kk esa Header Files dgk x;kA

gkykafd Function Libraries dkQh gn rd Reusable Codes iznku djrs Fks ysfdu budh leL;k ;s Fkh fd buds }kjk Real World Objects dks Computer esa Logically Represent ugha fd;k tk ldrk Fkk] D;ksafd Functions Libraries egRoiw.kZ Data dks Include ugha djrs FksA lkFk gh ,d Function dks u, Program esa vPNh rjg ls Use djus ds fy, muesa Modifications Hkh djus iMrs FksA pwafd Functions ds :i esa Companies Source Code iznku djrs Fks ftUgsa ,d Programmer viuh vko”;drkuqlkj Modify dj ldrk Fkk ysfdu tc Programmer mUgsa Modify djrk Fkk rks mls okil mu Functions ds Bugs dks Debug djuk iMrk FkkA OOPS ds Concept }kjk ,d u;k rjhdk lkeus vk;k ftlls Reusability dkQh ljy gks xbZ vkSj ;s rjhdk Fkk Class Libraries dkA D;ksafd ,d Class Real World Object dks vPNh rjg Modal djrk gS blfy, bls u, okrkoj.k esa mi;ksx esa ysus ds fy, blesa T;knk Modification djus dh vko”;drk ugha gksrh gSA OOPS gesa ,d ,slk rjhdk iznku djrk gS ftlls fcuk Class ds Coding dks ifjofrZr fd, gq, Class dks Modify fd;k tk ldrk gS vkSj fQj ls mi;ksx esa yk;k tk ldrk gSA ;s fo”ks’krk OOPS esa Inheritance Concept ds dkj.k gesa izkIr gksrh gSA bl


Java in Hindi Concept esa fdlh iqjkuh Class (Super Class) dgrs gSa] mls Modify ugha djuk gksrk gS cfYd ,d ubZ Class (Sub Class) cuk;h tkrh gS vkSj mlesa iqjkuh Class ds lHkh Features dks Derive dj fy;k tkrk gS lkFk gh viuh vko”;drkuqlkj u, Features dks Hkh bl ubZ Class esa Add dj fy;k tkrk gSA bl izfØ;k dks OOPS esa Inheritance dgrs gSaA

Inheritance and Program Design

iqjkus Codes dks Modify djds Use djus esa ljyrk iznku djuk Inheritance dh ,d vkSj fo”ks’krk gSA Inheritance gesa ,d Program ds Components dks nwljs Program ls Relate djus ;k u, Program esa tksMus dk ,d u;k rjhdk iznku djrk gSA ;s u, izdkj dh Relationship Program dks Design djus ds fy, Extra Flexibility iznku djrk gS vkSj Programmer dks ;s lqfo/kk iznku djrk gS fd og Program Architecture dks bl izdkj ls Design dj lds fd Program T;knk ls T;knk Accurate rjhds ls Real World Relationship dks Reflect djsA Inheritance ds Concept ds vk/kkj ij ge ,d Class ls dbZ vU; Classes dk Relation cuk dj dbZ vU; ubZ Classes cuk ldrs gSa] ftUgs Sub Class dgk tkrk gSA Inheritance dks dbZ ckj “Kind of” Relationship }kjk Represent fd;k tkrk gSA bl Relationship dk eryc le>us ls igys ge ,d vU; Relationship dks le>saxs ftls “Has a” Relationship ;k Composition dgk tkrk gSA

Composition: A “Has a” Relationship geus igys Hkh Composition dks vius Program esa dbZ ckj Use fd;k gSA ge ftruh Hkh ckj fdlh Class esa ,d Instance Data Member Place djrs gSa] ge ,d “Has a” Relationship cuk jgs gksrs gSaA tSls ;fn ,d Employee Class gS vkSj mlesa name uke dk ,d Data Item gS] rks ge ;s dg ldrs gSa fdl Employee dk ,d uke gS ;k ;fn English Language esa dgsa rks dg ldrs gSa fd% Employee “Has a” Name

blh rjg ls ,d Employee Object dk ID gks ldrk gS, Salary gks ldrk gS] vkfnA ;fn ge Relationship ds vk/kkj ij bUgsa Hkh Describe djuk pkgsa rks dg ldrs gSa fd% Employee “Has a” ID Employee “Has a” Salary Object o mlds Features ds chp bl izdkj ds Relationship dks Composition dgk tkrk gS D;ksafd ,d Employee Object bu Features dks Represent djus okys Variables dk ,d Composition gSA

blh rjg ls Stack Class esa Stack ds Data dks Hold djus ds fy, ,d Array dks vkSj Index Number dks Store djus ds fy, ,d top Variable, Member Data ds :i esa gks ldrs gSaA bl Stack Class ds ckjs esa ;fn ge dguk pkgsa rks dg ldrs gSa fd ,d Stack Object ,d Array vkSj ,d Stack-Top Index dk Composition gS ;k dg ldrs gSa fd ,d Stack esa ,d Array gS vkSj ,d top Index Variable gSA ;kuh 286 Any Question or Suggestion, Just Discuss Here...

Java in Hindi Stack “Has a” StackArray Stack “Has a” topIndex

ge fdlh Class esa fdlh nwljh Class ds Object dks Hkh ,d Member Data Variable ds :i esa Declare dj ldrs gSaA ;kuh ;fn ge pkgsa rks fdlh School Class esa fdlh Student Class ds Object dks Hkh Data Member ds :i esa Declare dj ldrs gSaA blh rjg ls ge ,d Bicycle Class esa Frame Object dks Data Member ds :i esa j[k ldrs gSa tks fd fdlh vU; Class dk ,d Object gSA OOPS esa Composition fdlh Real World Object dks bl rjg ls Represent djrk gS] ftlesa ,d Object dbZ vU; Objects dk cuk gqvk gks ldrk gSA ;fn ge ,d Family Relationship ds vk/kkj ij “Has A” Relationship dks Represent djsa rks ge fuEukuqlkj fp= }kjk bl Relationship dks le> ldrs gSa% A Has – A / Part – Of Relationship ( “ds ikl . . . gS” @ “dk ,d Hkkx gS” lEca/k) ,d Human Being Class ds ikl ,d Heart gS vkSj ,d Heart Human Being Class dk

,d Hkkx gSA

Part – Of Human Being

Mammal Has – A

“Has a” Relationship o “Part of” Relationship vkil esa Interchangeable gksrs gSaA “C” Language esa bl “Has a” Relationship dks Structure }kjk Represent fd;k tkrk FkkA ;kuh ,d Structure dbZ vU; Variables o Structures ls Composed gksrk FkkA ysfdu ,d vkSj Relationship gksrh gS ftls “C” Language tSlh Procedural Languages Modal ugha dj ldrs gSaA bl Relationship dks “Kind of” Relationship dgk tkrk gSA

Inheritance: A “Kind of” Relationship OOPS Real World ds ml Concept dks Represent djrk gS] ftls Generalization dgk tkrk gSA ;kuh ;fn ,d Maruti Car gS] ,d Tata Sumo Car gS vkSj ,d Ferrari Car gS] rks ge dg ldrs gSAa ;s rhuksa dkjsa ,d General Concept ftls Car dgrs gSa] ds Specific mnkgj.k gSaA bu lHkh dkjksa esa Wheels gksrs gSa] ysfdu gks ldrk gS fd Maruti Car ds Wheels dh pkSMkbZ de gks vkSj Ferrari Car ds Wheels dh pkSMkbZ vf/kd gksA blh rjg ls gks ldrk gS fd Tata Sumo Car ds Steering dk O;kl vU; dkjksa dh rqyuk esa vf/kd gksA ;kuh rhuksa Cars dh General Specification ds eku esa vUrj gks ldrk gS] tcfd rhuksa Cars ds Attributes leku Features dks Share djrs gSaA ysfdu fQj Hkh ge ;s dg ldrs gSa fd Maruti ,d izdkj dh Car gSA blh rjg ls Tata Sumo Hkh ,d izdkj dh Car gS vkSj Ferrari Hkh ,d izdkj dh Car gSA ;fn ge bls English Language esa dgsa rks dg ldrs gSa fd%


Java in Hindi Maruti is a “Kind of” Car Ferrari is a “Kind of” Car Tata Sumo is a “Kind of” Car

blh rjg ls ekuk ge ,d Employee Class cukrs gSaA ysfdu Employee Hkh dbZ izdkj ds gks ldrs gSaA tSls Labor, Manager, Scientist vkfnA ;s lHkh fdlh Company ds Employee gks ldrs gSa] ysfdu ;s lHkh vyx&vyx izdkj ds (Kind of) Employee gSaA fQj Hkh gj Employee dk Employee Class ls ,d lEca/k gS] tks buds vyx&vyx izdkj ds Employee gksus dks Represent gSA ;s nksuksa mnkgj.k Cars o Employees dh General Category dks Represent djrs gSaA ge gekjs nSfud thou esa Hkh Generalization dks dkQh Use djrs gSaA ge tkurs gSa fd ?kksMk] xk;] vkneh] vkSjr vkfn lHkh ltho izdkj ds mnkgj.k gSaA blh rjg ls Car, Bus, Truck vkfn Vehicle izdkj ds mnkgj.k gSaA Macintosh, o PCs Computer izdkj ds mnkgj.k gSaA bu lHkh Relationships dks ;fn ge English Hkk’kk esa Represent djsa rks dg ldrs gSa fd Human Being is “a Kind” of Mammal Dog is “a Kind” of Mammal Horse is “a Kind” of Mammal Maruti is “a Kind” of Car Ferrari is “a Kind” of Car Tata Indica is “a Kind” of Car

;kuh ge dg ldrs gSa fd Real World esa gj Object dk mldh Class ls ,d izdkj dk “Kind of” lEca/k gksrk gS blh rjg ls gj Object Attributes ;k Features dk ,d Composition gksrk gSA tc Real World esa Physically fofHkUu izdkj ds Objects ds chp bl izdkj dk lEca/k gksrk gS] rks Logically ;gh lEca/k gesa Computer esa Hkh Establish djuk t:jh gS rHkh ge fdlh Computer Language dks Object Oriented Language dg ldrs gSaA Inheritance Objects dh Classes ds chp blh Relationship dks Establish djus dh {kerk iznku djrk gSA Kind Of Relationship ( “,d izdkj dk” lEca/k ) bUlku o tkuoj nksuksa gh ltho izk.kh gSaA nksuksa ds gh T;knkrj Characteristics ,d leku gksrs gSaA tSls nksuksa ds ikl nks vka[ksa] ,d ukd] ,d eqag] nks dku gksrs gSa vkSj nksuksa gh py ldrs gSa] Hkkx ldrs gSa] f”kdkj dj ldrs gSa] vkfnA blfy, ge ;s dg ldrs gSa fd bUlku ,d izdkj dk ltho gS vkSj dksbZ tkuoj tSls fd “ksj Hkh ,d izdkj dk ltho gSA bls ge fuEukuqlkj fp= }kjk Hkh n”kkZ ldrs gSa% ,d izdkj dk

bUlku

ltho

bUlku ,d izdkj dk ltho gSA bls vaxzsth Hkk’kk esa Describe djsa rks ge dg ldrs gSa fd%


Java in Hindi Human Being is a Kind of Mammal.

blh rjg ls ge ,d “ksj dks Hkh fuEukuqlkj Represent dj ldrs gSa%

Human Being

A Kind Of

Mammal

Is – A Relationship ( “,d . . . gS” lEca/k) fiNys mnkgj.k esa geus ns[kk fd bUlku o “ksj ltho Class ds nks mnkgj.k gSaA vc ge ,d Human Being Class ds Instance ftldk uke Rahul Sharma gS] dks n[krs gSa] tks fd% ,d Human Being gS vkSj ,d izdkj dk ltho gSA ;kuh% Is – A Rahul Sharma

A Kind Of Human Being

Mammal

Is – A Computer eas fdlh Logical Class dks fdlh nwljh Logical Class ls Logically Relate dj ldrs gSa vkSj fofHkUu izdkj dh Relationship dks iz;ksx djrs gq, ge fdlh Class dks fcuk Rewrite fd, gq,] fQj ls Reuse dj ldrs gSaA

,d mnkgj.k }kjk le>sa rks ,d cPps esa mlds ekrk o firk nksuksa ds xq.k vkrs gSa] ftUgsa vkuqokaf”kd xq.k dgrs gSaA blh vkuqokaf”kdrk ds fl)kar dk iz;ksx Object Oriented Concept ds :i esa Computer esa fd;k tkrk gSA vkuqoakf”kdrk ds bl xq.k dks OOPS esa Inheritance dgk tkrk gSA Inheritance ,d ,slk rjhdk gksrk gS] ftlesa ;fn nks leku izdkj ds Objects gksa] rks ,d Object nwljs Object ds Attributers (State) o Behaviors (Ability) dks Use dj ldrk gSA bl fl)kar ds vk/kkj ij gh Object Oriented Programming Languages esa Reusability

dk fodkl fd;k x;k gSA

Superclass and Subclass

Computer ds Inheritance dks ge ,d mnkgj.k }kjk le>us dh dksf”k”k djrs gSaA ekuyks fd ge Railway Reservation dk Software cuk jgs gSaA bl Software esa fdlh Hkh le; nks rjg ds Tickets gks ldrs gSa% 1 2

Confirmed Ticket Waiting Ticket


Java in Hindi bu nksuksa izdkj ds Tickets ds dbZ vU; Attributes gks ldrs gSaA tSls% 1 2 3

4

Train Number Date Time Destination

fQj Hkh ,d Confirmed Ticket esa Seat Number uke dk ,d Extra Attribute gksxk] tcfd Waiting Ticket esa ,d Status Attribute gksxk] tks Ticket dh fLFkfr dks n”kkZ,xkA

mijksDr fp= esa geus nks Classes ds Common Structure o Attributes dks ifjHkkf’kr fd;k gS] tks fd Super Class Represent djrk gSA ;kuh Ticket ,d ,slh Common Class gS ftlds Attributes o Behaviors dks blds uhps dh nksuksa Sub Classes Confirmed Ticket o Waiting Ticket izkIr djrh gSaA pwafd Ticket Class dks ge ,d ,slh Class ds :i esa ns[k ldrs gSa] tks fd blds uhps dh nksuksa Classes ds fy, Common Attributes o Behaviors dks Represent djrk gS] blfy, bl Class dks Generalized Class dgrs gSaA tcfd Confirmed Ticket o Waiting Ticket nks ,slh Classes gSa] tks bldh Super Class Ticket ds Attributes o Behaviors dks rks izkIr djrs gh gSa] lkFk gh buds Lo;a ds Hkh dqN Attributes o Behaviors gks ldrs gSa] ;kuh ;s Classes T;knk Modified gks ldrh gSa vkSj fdlh ,d dke dks T;knk Special rjhds ls Represent dj ldrh gSa] blfy, bu Sub Classes dks Specialized Class dgrs gSaA Super Class ,d ,slh Class gksrh gS] ftlls vU; Classes Common Properties dks izkIr djrh gSaA ;s Classes viuh Properties dks vius ls Inherit gksus okyh Classes ds lkFk Share djrh gSaA tcfd ,d Sub Class og Class gksrh gSa] tks fdlh Super Class dh Properties ;kuh Attributes o Methods dks izkIr djrk gS vkSj T;knk Specialized rjhds ls mUgsa Use djrk gSA

dksbZ Hkh Sub Class dHkh Hkh viuh Super Class ds Constructors dks Inherit ugha djrk gS] D;ksafd Contractors dk vius Compiler ds fy, fo”ks’k Meaning gksrk gSA Sub Classes ds Lo;a ds Constructors Hkh Create fd, tk ldrs gSa] tgka Super Class ds Constructor ds ekuksa dks Hkh Initialize fd;k tkrk gSA ,d Sub Class dk mldh Super Class ds Data Members o Member Methods ds vykok Loa; dk Hkh Data Member o Method gks ldrk gSA lkekU;r;k dbZ Programming Languages esa Super Class dks Base Class o Sub Class dks Derived Class Hkh dgk tkrk gSA


Java in Hindi fiNys fp= esa geus ns[kk fd Ticket Class ,d Generalized Class gSA ,d Generalized Class dk iz;ksx bl izdkj ds Programs dks fy[kus ds fy, fd;k tkrk gS tks fd cgqr T;knk General ;kuh Common :i ls dke esa vkrs gSaA ekuyks fd geus ,d ,slk Program cuk;k tks fd User ls Input ds :i esa ,d String izkIr djrk gS vkSj Output esa ml String dks Screen ij Print dj nsrk gSA ysfdu vc gekjh Requirement Change gks xbZ gS vkSj gesa Screen ij String ds LFkku ij fdlh Integer eku dks Print djuk gSA bl fLFkfr esa gesa gekjh fiNyh okyh Class dks Modify djuk gksxkA ekuyks fd gekjs ikl Super Class ds :i esa Data Class gS] ftlesa blds eku dks Display djus ds fy, ,d Method gSA Data Class dh Sub Class ds :i esa gekjs ikl Character o Float Class Hkh gSA vc ,d Integer izdkj ds eku dks Screen ij Print djus ds fy, gesa ,d Integer Class Create djuh gksxh] tks fd Data Class dh ,d Sub Class gSA Data Class esa ,d vkSj Sub Class dks Add djus ij Data Class dh igys ls Created Character o Float Sub Class esa dksbZ Effect ugha gksxkA pwafd Super Class Data esa Character Class o Float Class ds ekuksa dks Screen ij Print djus dk Method Super Class Data esa igys ls gh fy[kk tk pqdk gS] blfy, gesa Integer izdkj ds eku dks Screen ij Print djus ds fy, Hkh vyx ls Display() Method fy[kus dh t:jr ugha gSA ge Data Super Class ds Display() Method dks Integer Class esa Inherit djds ,d Integer izdkj ds eku dks Hkh Screen ij Print dj ldrs gSaA Generalization ,d ,slk rjhdk gS] tks gesa Abstraction djus esa enn djrk gSA OOPS esa eq[; egRo ,slh Classes Develop djus dk gksrk gS] tks vkil esa Data o Methods dks Share dj ldsa] lkFk gh Data dh Hkh Security cuh jgsA ;kuh ,d Unauthorized Class fdlh Hkh rjg ls fdlh nwljh Class ds Data dks Access ugha dj ldsA Encapsulation gh og rjhdk gS] ftlls Data dh Security dks izkIr fd;k tk ldrk gSA

fdlh Class dks dc Generalized Form esa Create djuk pkfg,] bldk dksbZ fuf”pr fu;e ugha gSA blfy, fdl izdkj dh Class dks Generalized djuk gS vkSj fdls ugha] bl ckr dk fu.kZ; ysus dh {kerk vuqHko ls izkIr gksrh gSA tkok esa ge dsoy Single Inheritance Concept dks gh Use dj ldrs gSaA ;kuh tkok esa ge dsoy ,d gh Super Class ds Attributes o Behaviors dks ubZ Class esa izkIr dj ldrs gSaA

Implementing Inheritance

Inheritance ds ,d lcls ljy mnkgj.k esa Hkh de ls de nks Classes gksrh gSaA ewy Class dks tkok esa Super Class dgk tkrk gS tcfd “C++” esa bls Base Class dgk tkrk gSA blh rjg ls ewy Class ls Derive dh tkus okyh Class dks tkok esa Sub Class dgk tkrk gS] tcfd “C++” esa Inherit gksus okyh Class dks Derived Class dgk tkrk gSA

tkok esa fdlh Super Class ds xq.kksa dks fdlh ubZ Class esa Derive djus ds fy, gesa extends Keyword dk iz;ksx djuk gksrk gSA tc ge fdlh Super Class ds xq.kksa dks fdlh Sub Class esa Inherit djrs gSa] rc okLro esa ge Super Class ds General xq.kksa dks viuh


Java in Hindi t:jr ds vk/kkj ij c { // Attributes and Methods } public class extends { // Attributes and Methods }

bl Code Segment esa extends dk eryc ;s gksrk gS fd ge Super Class dks Extend djds ,d ubZ Sub Class cuk jgs gSa] ftlesa Super Class ds rks lHkh Instance Member o Methods gksrs gh gSa] lkFk gh Sub Class ds Lo;a ds Hkh dqN Special Instance Members o Methods gks ldrs gSaA Super Class ds Data Members o Methods ds Access Specifies ds vk/kkj ij gh ;s r; gksrk gS fd Sub Class Super Class ds fdu Data Members o Methods dks fdl gn rd Access djus esa l{ke gksxk o fdl fLFkfr esa Access djus esa l{ke gksxkA OOPS dk ,d lkekU; lk fu;e ;s gksrk gS fd fdlh Hkh Object ds Data Members dks Access djus ds fy, mlh Object ds Methods gh l{ke gksrs gSaA blfy, lkekU;r;k fdlh Hkh Super Class ds Data Members dks Private j[kk tkrk gSA tcfd bu Data Members dks Access djus ds fy, bUgha dh Classes esa dqN Public Member Functions ;k Public Methods gksrs gSaA bu Methods dk iz;ksx djds gh dksbZ Outer Method bl Class ds Data dks Access dj ldrk gSA Inheritance esa Access Specifier dkQh egRoiw.kZ dke djrs gSaA

buds vk/kkj ij gh fdlh Object dh dqy {kerk dk irk yx ikrk gS] fd dksbZ Specific Object D;k&D;k djus esa l{ke gSA tkok esa dqy pkj izdkj ds Access Specifier gksrs gSa tks Class ds Inherit gksus dh {kerk dks fu/kkZfjr djrs gSaA tc ge fdlh Class dks Create djrs le; fdlh Access Specifier dk iz;ksx ugha djrs gSa] rc Class Default Access Specifier dk iz;ksx djrk gSA Default Access Specifier ds vk/kkj ij Create gksus okyh Classes ftl Package esa gksrh gSa] mUgsa mlh Package dh lHkh vU; Classes Directly Access djus esa l{ke gksrh gSaA ysfdu fdlh nwljs Package dh Class Default Access Specifier okyh Class dks Access ugha dj ldrh gSA Program // File Name : InheritanceDemo class Employee {


Java in Hindi }

int ID; String name;

// By Default Friend Data Members // By Default Friend Data Members

class Scientist extends Employee { float salary; // By Default Friend Data Members } class InheritanceDemo { public static void main(String args[]) { Employee you = new Employee(); Scientist me = new Scientist(); you.ID = 1000; you.name = "Mohan"; me.ID = 2000; me.name = "Govind"; // you.salary = 12000; Error: // Employee does not know about salary Data Member of Scientist me.salary = 15000; System.out.println("Your Information"); System.out.println("\tName : " + you.name); System.out.println("\tID : " + you.ID);

}

}

System.out.println("\nMy Information"); System.out.println("\tName : " + me.name); System.out.println("\tID : " + me.ID); System.out.println("\tSalary : " + me.salary);

Output Your Information Name : Mohan ID : 1000 My Information Name : Govind ID : 2000 Salary : 15000.0


Java in Hindi bl mnkgj.k esa geus nksuksa gh Classes dks ,d gh Program File esa Create fd;k gSA tc ge ,d gh Program File esa Super Class o Sub Class nksuksa dks Create djrs gSa] ml fLFkfr esa ;fn ge Classes ds lkFk fdlh Hkh Access Specifier dk iz;kssx uk djsa] rc Hkh Program esa fdlh rjg dh dksbZ Error ugha vkrh gSA blh rjg ls ;fn ge Super Class o Sub Class dks nks vyx Files esa j[krs gSa vkSj main() Method Class dh File dks Hkh vyx ls fy[krs gSa] ysfdu rhuksa gh Classes dks leku Folder esa Store djrs gSa] rks Hkh lHkh Classes fcuk fdlh O;o/kku ds vkil esa Communication dj ysrh gSa] pkgs geus fofHkUu Classes dks public Specifier ds lkFk Create uk fd;k gksA ,slk blfy, lEHko gS] D;ksafd tc ge fdlh Class dks Create djrs le; fdlh Access Specifier dk iz;ksx ugha djrs gSa] rc lHkh Classes Default Access Specifier dk iz;ksx djds Create gksrh gSaA bl fLFkfr esa ,slh lHkh Classes ,d nwljs dh Friend gksrh gSaA blfy, lHkh Classes dks leku Package dh lHkh vU; Classes Directly Use dj ldrh gSaA gkykafd geus vHkh rd Package ugha cuk;k gS] ysfdu fQj Hkh ge ;s eku ldrs gSa fd vkil esa Communicate djus okyh fofHkUu Class Files leku Folder esa Stored gSa] blfy, og Folder ,d Package ds leku gh gS vkSj ,d gh Package ;k ,d gh Folder esa Stored lHkh Class Files vkil esa Friend gksus dh otg ls Directly Communicate djus es l{ke gksrh gSaA gekjs bl mnkgj.k esa Employee Class ,d Super Class gS] ftlesa nks Data Members gSa] tcfd Scientist Class Employee Class dh Sub Class gS] ftlesa ,d Data Member gSA tkok esa fdlh Class ds lHkh Data Member o Methods By Default friendly gksrs gSaA tkok esa friendly dksbZ Keyword ugha gS cfYd Access Level Specify djus dk ,d ek/;e gS vkSj tc Hkh ge fdlh Class ;k Class ds Members (Data Member and Methods) ds lkFk fdlh Access Specifier dk iz;ksx ugha djrs gSa] rc Default Access Specifier ds :i esa Friendly Access Specifier Apply gks tkrk gSA blh otg ls main() Method esa geus Super Class Employee o Sub Class Scientist nksuksa ds Data Members dks Dot Operator dk iz;ksx djds Directly Access dj fy;k gSA ysfdu lkekU;r;k fdlh Hkh Class ds Data Members dks Public ;k Friendly ugha j[kk tkrk gSA ;fn Data Member dks Public j[kk tkrk gS] rks Data dh dksbZ lqj{kk ugha jgrh gS vkSj bu Data Members ds Data dks dksbZ Hkh Method Change dj ldrk gS] tSlkfd geus main() Method esa Super Class o Sub Class nksuksa gh Classes ds Members dks Directly Value Assignment fd;k gSA tc ge Data dh lqj{kk dh ckr djrs gSa] rc gesa fdlh Hkh Class ds Data dks Private j[kuk gksrk gSA fdlh Data Member dks Private j[kus ds fy, gesa Data Member Declare djrs le; private Keyword dk iz;ksx djuk gksrk gSA ysfdu tc ge fdlh Class ds fdlh Data Member dks Private Declare djrs gSa] rc ge ml Class ds ml Private Data dks fdlh Hkh vU; Class esa Directly Access ugha dj ldrs gSaA bl fLFkfr esa gesa ,sls Methods cukus gksrs gSa tks Public ;k Friendly gksrs gSa vkSj D;ksafd ge Public Methods dks Directly fdlh Hkh Class esa Access dj ldrs gSa] blfy, gesa bu 294 Any Question or Suggestion, Just Discuss Here...

Java in Hindi Public Methods }kjk gh fdlh Hkh Class ds Private Data dks Access djus dh lqfo/kk izkIr gksrh gSA ;kuh ;fn ge fiNys Program ds gh Data Members dks Modify djds Private dj nsa] vkSj Program dks Compile djsa] rks gesa fuEukuqlkj Compile Time Error izkIr gksrh gS% Program class Employee { private int ID; private String name; } class Scientist extends Employee { private float salary; } class InheritanceDemo { public static void main(String args[]) { Employee you = new Employee(); Scientist me = new Scientist(); you.ID = 1000; you.name = "Mohan"; me.ID = 2000; me.name = "Govind"; // you.salary = 12000; Error: // Employee Class does not know about salary Data Member me.salary = 15000; System.out.println("Your Information"); System.out.println("\tName : " + you.name); System.out.println("\tID : " + you.ID);

}

}

System.out.println("\n\nMy Information"); System.out.println("\tName : " + me.name); System.out.println("\tID : " + me.ID); System.out.println("\tSalary : " + me.salary);

Output D:\Java\InheritanceDemo.java:20: ID has private access in Employee you.ID = 1000; ^ D:\Java\InheritanceDemo.java:21: name has private access in Employee 295 Any Question or Suggestion, Just Discuss Here...

Java in Hindi you.name = "Mohan"; ^ D:\Java\InheritanceDemo.java:23: ID has private access in Employee me.ID = 2000; ^ D:\Java\InheritanceDemo.java:24: name has private access in Employee me.name = "Govind"; ^ D:\Java\InheritanceDemo.java:28: salary has private access in Scientist me.salary = 15000; ^ D:\Java\InheritanceDemo.java:32: name has private access in Employee System.out.println("\tName : " + you.name); ^ D:\Java\InheritanceDemo.java:33: ID has private access in Employee System.out.println("\tID : " + you.ID); ^ D:\Java\InheritanceDemo.java:36: name has private access in Employee System.out.println("\tName : " + me.name); ^ D:\Java\InheritanceDemo.java:37: ID has private access in Employee System.out.println("\tID : " + me.ID); ^ D:\Java\InheritanceDemo.java:38: salary has private access in Scientist System.out.println("\tSalary : " + me.salary); ^ 10 errors

;kuh ;fn gesa fdlh Class ds Private Data dks fdlh nwljh Class esa Use djuk gks] rks gesa mlh Class ds Public Methods dk iz;ksx djuk iMrk gSA ftl rjg ls ge fdlh Class ds Data Members dks Private Declare dj ldrs gSa] mlh rjg ls ge fdlh Class ds Methods dks Hkh Private Declare dj ldrs gSaA ysfdu ;gka Hkh Bhd ogh fu;e ykxw gksrk gS fd ge fcuk fdlh Public Method ds fdlh Class ds Private Method dks Hkh Access ugha dj ldrs gSaA blfy, lkjka”k ;s gqvk fd fdlh Hkh Class ds Data dks gesa”kk Private j[kk tkrk gS vkSj ml Class ds Data dks Access djus ds fy, gesa Public Methods dh t:jr gksrh gSA vc pwafd geus fiNys Program esa nksuksa gh Classes ds Data Members dks Private dj fn;k gS] blfy, bu Data Members dks Access djus ds fy, gesa mUgha Classes esa Public Methods Define djus gksaxs vkSj mUgha Public Methods }kjk muds Private Data dks Access djuk gksxkA bl fLFkfr esa gesa mijksDr Program dks fuEukuqlkj Modify djuk gksxk% Program class Employee { private int ID; private String name; public void setEmpData(int empID, String empName) 296 Any Question or Suggestion, Just Discuss Here...

Java in Hindi {

}

ID = empID; name = empName;

} public void showEmpData() { System.out.println("\tName : " + name); System.out.println("\tID : " + ID); }

class Scientist extends Employee { private float salary;

}

public void setScientistData(float sciSalary) { salary = sciSalary; } public void showScientistData() { System.out.println("\tSalary : " + salary); }

class ModifiedInheritanceDemo { public static void main(String args[]) { Employee you = new Employee(); Scientist me = new Scientist(); you.setEmpData(1000, "Mohan"); me.setEmpData(2000, "Govind"); me.setScientistData(15000); System.out.println("Your Information"); you.showEmpData(); System.out.println("\nMy Information"); me.showEmpData(); me.showScientistData(); } } Output Your Information Name : Mohan ID : 1000 My Information Name : Govind


Java in Hindi ID : 2000 Salary : 15000.0 Real World esa Hkh ge ns[krs gSa fd gj Scientist Object Employee gks ldrk gS] ysfdu gj Employee Scientist ugha gks ldrkA ;kuh gj Scientist ,d izdkj dk (Kind Of) Employee gks ldrk gS ysfdu gj Employee ,d izdkj dk Scientist ugha gks ldrkA lkjka”k ds :i esa ge ;s Hkh dg ldrs gSa fd Super Class o Sub Class nksuksa esa “Kind Of” Relationship gksrh gSA

,d Derived Class ;k Sub Class esa mldh Methods Inherit gksrs gSa] blfy, Sub Class Members o Methods ds ckjs esa tkurk gksrk Members dks rks Access dj gh ldrk gS] lkFk Access dj ldrk gSA

Super Class ds lHkh Data Members o gesa”kk viuh Super Class ds lHkh Data gSA ;kuh ,d Sub Class viuh Class ds gh viuh Super Class ds Members dks Hkh

ysfdu ,d Super Class dsoy vius gh Members dks Access djus esa l{ke gksrk gSA mldh Sub Class esa dkSuls u, Members Add fd, x, gSa] bldh tkudkjh Super Class dks dHkh Hkh ugha gksrh gSA ;gh otg gS fd InheritanceDemo Program esa Employee Super Class dk Object Scientist Sub Class ds Object ds salary Data Member dks Access ugha dj ldrk gSA bl Program esa geus you.salary Statement dks Comment cuk;k gSA ;fn ge bls ,d Normal Statement cuk nsa] rks Program Compile ugha gksrk gSA D;ksafd Super Class ds Object dks Sub Class ds Data Member ds ckjs esa dHkh Hkh dksbZ tkudkjh ugha gksrh gSA Default Access Specifier, Public Access Specifier, Private Access Specifier o Protected Access Specifier bu lHkh Access Specifier dks Data Members, Methods o Class rhuksa ds lkFk muds Scope dks Specify djus ds fy, Use fd;k tkrk gSA Private Access Specifier dks dsoy Data Members, Methods o Inner Classes ds fy, gh Use

fd;k tk ldrk gSA

tcfd Public Access Specifier dk iz;ksx Class, Methods o Data Members ds lkFk dj ldrs gSa] ysfdu fdlh Inner Class ds lkFk ge Public Access Specifier dk iz;ksx ugha dj ldrs gSaA ge ftl fdlh Hkh Inner Class, Method ;k Data Member dks Protected Declare djrs gSa] mls mldh Derived Classes esa Directly Access fd;k tk ldrk gSA ;kuh Protected Access Specifier dk iz;ksx djds Define dh xbZ Inner Class] Method ;k Data Members dks dsoy mudh Derived Classes ;k Sub Classes esa gh Directly Access fd;k tk ldrk gSA “ks’k Classes ds fy, ;s iwjh rjg ls Private ;k Inaccessible jgrs gSaA ge fdlh External Class dks Protected Define ugha dj ldrs gSaA bl Discussion ds vk/kkj ij ;fn ge fiNys Program esa Use fd, x, fofHkUu izdkj ds Access Specifier dks gVk nsa] rks Hkh gekjk Program lkekU; rjhds ls dke djrk gS] D;ksafd ml fLFkfr esa Hkh lHkh Classes, Data Members o Methods Friendly Access Level esa gksrs gSaA


Java in Hindi Method Overriding

fdlh Super Class esa fdlh Method dk tks Signature gksrk gS] mlh Signature dk Method tc ge Sub Class esa Create djrs gSa] rks bl izfØ;k dks Method Overriding dgk tkrk gSA tcfd Super Class o Sub Class nksuksa esa gh Method dk uke leku gks] ysfdu muds Signature esa vUrj gks] rks fQj pkgs ;s Methods Super Class esa gksa pkgs Sub Class esa ,sls Methods Overloaded Methods dgykrs gSa vkSj bl izfØ;k dks Method Overloading dgk tkrk gSA Method Overloading ds ckjs esa ge fiNys v/;k; esa i< pqds gSaA bl v/;k; esa ge Method Overriding ds ckjs esa tkusaxsA fiNys Program esa geus Super Class ds Data dks Set djus ds fy, setEmpData() uke dk Method cuk;k gS tcfd Sub Class ds Data dks Set djus ds fy, setScientistData() uke dk Method cuk;k gSA ge le> ldrs gSa] fd nksuksa gh Classes esa Object ds Data dks Set djus dk gh dke gks jgk gS] fQj Hkh Super Class ds Data o Sub Class ds Data nksuksa dks Set djus ds fy, gesa vyx&vyx uke ds Methods dks Call djuk iM jgk gSA bl fLFkfr esa ge Super Class ds Method dks Override djds ,d Common uke ns ldrs gSa] ftlls gesa nksuksa gh Classes ds Objects dks eku Set djus ds fy, nks vyx Method dks Call djus dh t:jr ugha gksxh cfYd ge nksuksa gh LFkkuksa ij ,d gh uke ds Method dks Use dj ldrs gSaA bl rjg dk ifjorZu djus ij gekjk Program fuEukuqlkj cu tk,xk% Program class Employee { private int ID; private String name; public void setData(int empID, String empName) { ID = empID; name = empName; }

}

public void showData() { System.out.println("\tName : " + name); System.out.println("\tID : " + ID); }

class Scientist extends Employee { private float salary; public void setData(int empID, String empName, float sciSalary) { super.setData(empID, empName); salary = sciSalary; }


Java in Hindi

}

public void showData() { super.showData(); System.out.println("\tSalary : " + salary); }

class InheritanceDemo { public static void main(String args[]) { Employee you = new Employee(); Scientist me = new Scientist(); you.setData(1000, "Mohan"); me.setData(2000, "Govind", 15000); System.out.println("Your Information"); you.showData();

}

System.out.println("\nMy Information"); me.showData();

Output Your Information Name : Mohan ID : 1000 My Information Name : Govind ID : 2000 Salary : 15000.0

bl Modified Program esa geus Super Class o Sub Class nksuksa esa gh leku dke djus okys Methods ds uke leku dj fn, gSaA tc ge Sub Class Scientist dk Object Create djrs gSa] rc bl Object dks Set djus ds fy, bl Class ds Object ds lkFk setData() Method dks Call djrs gSaA ,slk djus ij Sub Class dk setData() Method Call gksrk gS vkSj Sub Class ds setData() Method esa Super Class ds setData() Method dks Call fd;k gSA Super Class ds setData() Method dks Call djus ds fy, gesa super Keyword dk iz;ksx djuk t:jh gksrk gSA ;fn ge super Keyword dk iz;ksx uk djsa] rks Sub Class esa Super Class dk setData() Method rks Call gks tkrk gS] D;ksafd ge bl Method esa nks Argument Pass dj jgs gSa vkSj nks Argument okyk setData() Method Super Class esa gh gSA


Java in Hindi ysfdu tc ge showData() Method dks Call djrs gSa] rc pwafd Super Class o Sub Class nksuksa gh Classes esa showData() Method esa dksbZ Argument Pass ugha gks jgk gS] blfy, nksuksa gh Methods ds Signature leku gks x, gSaA bl fLFkfr esa tkok gesa”kk Sub Class ds gh showData() Method dks Execute djrk gS] Super Class ds showData() Method dks ughaA pwafd ge Sub Class ds showData() Method ls Super Class ds showData() Method dks Execute djuk pkgrs gSa] blfy, gesa bl super Keyword dk iz;ksx setData() Method ls igys djuk t:jh gksrk gSA super Keyword ,d ,slk Keyword gS] tks gesa”kk viuh Super Class dks gh Refer djrk gSA blfy, ;fn gesa Super Class ds fdlh ,sls Method dks Call djuk gks] ftldk uke o Parameters dh la[;k o Parameters ds Data Type rhuksa gh leku gksa] rks Super Class ds Method dks Call djus ds fy, gesa ,sls Method dks super Keyword ds lkFk Call djus ij Super Class dk Method Call gksrk gSA

ysfdu ;fn ge super Keyword ds lkFk bl izdkj ds Method dks Call uk djsa] rks Sub Class dk gh Method Call gksrk gSA fiNys Program esa ns[ksa rks showData() Method dk Signature Super Class o Sub Class nksuksa esa gh fuEukuqlkj gS% public void showData();

tcfd setData() Method dk Signature nksuksa gh Classes esa fuEukuqlkj vyx&vyx gSa% // In Super Class public void setData(int empID, String empName) // In Sub Class public void setData(int empID, String empName, float sciSalary)

pwafd nksuksa gh Classes esa setData() Method ds Signature vyx gSa] blfy, tc ge Sub Class esa Super Class ds setData() Method dks Call djuk pkgrs gSa] rc mlesa nks gh Arguments Pass djrs gSa] ftlls tkok Compiler nks Parameter okys setData() dks [kkstrk gS vkSj ;s Method mls Super Class esa izkIr gksrk gSA blfy, tkok Super Class ds setData() Method o Sub Class ds setData() Method esa rks vUrj dj ldrk gSA ysfdu tc ge showData() Method dh ckr djrs gSa] rc tkok ;s r; ugha dj ikrk gS fd mls Super Class ds setData() Method dks Call djuk gS] ;k Sub Class dsA ,slk blfy, gksrk gS D;ksafd tkok Compiler gesa”kk igys Sub Class esa gh setData() Method dks [kkstrk gSA ;fn mls leku Signature dk Method Sub Class esa izkIr ugha gksrk gS] rks tkok Compiler Super Class esa leku Signature ds Method dks [kkstrk gSA pwafd setData() Method dk Signature nksuksa gh Classes esa vyx gS] blfy, tkok igpku ysrk gS fd mls fdl Class ds setData() Method dks Execute djuk gS] ysfdu showData() Method nksuksa gh Classes esa leku gS] blfy, tkok Sub Class ds showData() Method dks Execute djrs le; tSls gh Super Class ds showData() Method dks [kkstrk gS] mls Sub Class dk gh Derive Method fey tkrk gS] D;ksafd nksuksa gh Classes esa bl Method ds Signature leku gSaA


Java in Hindi blfy, tkok gesa”kk Sub Class ds showData() Method dks gh Execute djus yxrk gS vkSj ,d izdkj dh Infinite Looping cu tkrh gSA bl izdkj dh fLFkfr ls cpus ds fy, tkok esa super Keyword dks Add fd;k x;k gSA ge ftl Class ds Object ds lkFk Currently izfØ;k dj jgs gksrs gSa] ml Object dks this Object Refer djrk gS] tcfd ge ftl Object ds lkFk Currently izfØ;k dj jgs gSa] ml Object dh Class ds Super Class dks gesa”kk super Object ;k super Keyword Refer djrk gSA ljy “kCnksa esa dgsa rks ge ;s Hkh dg ldrs gSa fd super ,d ,slk Object gksrk gS tks viuh Current Class dh Super Class dk Object gksrk gS vkSj bl Object ds Through ge fdlh Sub Class esa mldh Super Class dks Directly Access dj ldrs gSaA ftl rjg ls ge super Keyword ds lkFk Super Class ds Method dk iz;kssx djds Super Class ds Method dks Call dj ldrs gSa] mlh rjg ls ge super Keyword ds lkFk Super Class ds Data Members dks Hkh Access dj ldrs gSaA ;kuh ;fn ge pkgsa] rks ge Sub Class esa Super Class ds ID o name Field dks fuEukuqlkj Directly Access djds Set dj

ldrs gSa%

super.ID = 5000; super.name = “Gopal”

;fn ge bl Statement dks Sub Class ds setData() Method esa Use djuk pkgsa] rks mijksDr Program dh Sub Class ds setData() Method dks gesa fuEukuqlkj Modify djuk gksxk% public void setData(int empID, String empName, float sciSalary) { super.ID = empID; super.name = empName; salary = sciSalary; }

pwafd ;fn ge Derived Class ;k Sub Class Scientist esa fiNys setData() Method ds LFkku ij bl Method dks Use djuk pkgrs gSa] rks ,slk ge rHkh dj ldrs gSa tc Super Class Employee ds Data Members Public ;k Friend gksaA D;ksafd super Keyword Super Class ds dsoy Friend, Protected o Public Data Members o Methods dks gh Sub Class esa Directly Access djus dh lqfo/kk nsrk gSA

Constructors and Inheritance

fiNys Program esa geus Employee o Scientist nksuksa gh Classes ds Objects dks Initialize djus ds fy, setData() uke ds ,d Member Function dk iz;ksx fd;k gSA ysfdu ge bu Objects dks Constructors dk iz;ksx djds Hkh Initialize dj ldrs gSaA ;fn ge blh Program esa Define dh xbZ Super Class esa Constructors dk iz;ksx djsa] rks Employee Class dks ge fuEukuqlkj Modify dj ldrs gSa% class Employee { 302 Any Question or Suggestion, Just Discuss Here...

Java in Hindi private int ID; private String name; Employee(int empID, String empName) { ID = empID; name = empName; }

}

public void showData() { System.out.println("\tName : " + name); System.out.println("\tID : " + ID); }

vc ;fn ge bl Class ds Object Create djuk pkgsa] rks Object Create djrs gh mls fuEukuqlkj Initialize Hkh dj ldrs gSa% Employee you = new Employee(1000, “Mohan”);

pwafd ge tkurs gSa fd Constructor ,d ,slk Method gksrk gS] ftldk ogh uke gksrk gS] tks ml Method dh Class dk uke gksrk gS] ftlesa Method Define fd;k tkrk gSA tc ge bl izdkj dk Statement fy[krs gSa rc Compiler you Object dks Create djrs le; Employee Class ds 2-Argument Constructor dks Call djrk gS vkSj you Object ds nksuksa Data Members dks os eku Initialize dj nsrk gS] tks eku Arguments ds :i esa Object Create djrs le; Pass fd, tkrs gSaA vc ;fn ge bl Employee Class dks Extend djsa rks Extend gksus okyh Class esa Hkh ge Constructor Define dj ldrs gSaA ;kuh ;fn ge bl Modified Employee Class ds vk/kkj ij Scientist Class dks Hkh Modify djsa] rks bl Class dks Hkh ge fuEukuqlkj Define dj ldrs gSa% class Scientist extends Employee { private float salary; Scientist(int empID, String empName, float sciSalary) { super(empID, empName); salary = sciSalary; }

}

public void showData() { super.showData(); System.out.println("\tSalary : " + salary); }


Java in Hindi bl Class esa geus fQj ls super Keyword dk iz;ksx fd;k gS] ysfdu pwafd bl ckj super Keyword ls gesa Super Class ds fdlh Method dks Call ugha djuk gS] blfy, bls vdsys gh Use fd;k gSA ge ns[k ldrs gSa fd ;s Hkh ,d rjg dk Method gh gS] D;ksafd blds vkxs ,d Parenthesis gS ftlesa nks Arguments Pass fd, x, gSaA bl Method dks tkok esa super() Method dgk tkrk gS vkSj bl Method dks rHkh Use fd;k tkrk gS] tc gesa fdlh Sub Class esa ml Sub Class dh Super Class ds Constructor dks Call djuk gksrk gSA Scientist Class esa ;s super() Method Super Class Employee ds Constructor dks Call dj jgk gSA ;fn ge pkgsa rks vc ,d main() Method Class dks fuEukuqlkj Define dj ldrs gSa] ftlesa nksuksa gh Class ds Objects Create gks jgs gSa vkSj muds eku Initialize o Display

gks jgs gSa%

class ConstructorInheritance { public static void main(String args[]) { Employee you = new Employee(1000, "Mohan"); Scientist me = new Scientist(2000, "Govind", 15000); System.out.println("Your Information"); you.showData();

}

}


bl Program dk Hkh gesa ogh Output izkIr gksrk gS] tks fiNys Program dk gks jgk gSA bl Program esa geusa Employee Class o Scientist Class nksuksa Classes ds gh ,d&,d Object Create fd, gSaA tc ge Employee Class dk Object Create djrs gSa] rc pwafd Employee Class esa nks gh Data Members gSa] blfy, gesa Employee Class ds Constructor esa dsoy nks gh eku nsus gksrs gSa] ysfdu tc ge Scientist Class dk Object Create djrs gSa] rc gesa mlds Constructor esa rhu Arguments Pass djus gksrs gSaA tc ge Scientist Sub Class dk Object Create djrs gSa] rc bl Class dk 3-Argument Constructor Execute gksrk gS] tks fd fuEukuqlkj gS% Scientist(int empID, String empName, float sciSalary) { super(empID, empName); salary = sciSalary; }

bl Constructor ds igys Statement ds :i esa bldh Super Class ds Constructor dks super() Method dk iz;ksx djds Call fd;k x;k gSA pwafd Super Class ds Constructor dks gesa nks eku Pass djus gksrs gSa] ogh nksuksa eku ge super() Method esa Argument ds :i esa ns


Java in Hindi nsrs gSaA Super Class ds Data Members Initialize gksus ds ckn Sub Class ds Data Members Initialize gksrs gSaA ,d ckr gesa”kk /;ku j[ksa fd Inheritance dh Hierarchy esa gesa”kk lcls igys Super Class dk Constructor Execute gksrk gSA blfy, fdlh Hkh Sub Class Constructor esa gesa gesa”kk super() Method dks lcls igys Statement ds :i esa Define djuk t:jh gksrk gSA ;fn ge ,slk ugha djrs gSa] rks Compiler Error Generate djrk gS] D;ksafd tkok esa Internally Hkh lcls igys Super Class dk Constructor Execute gksrk gS vkSj Super Class ds Data Members Initialize gksus ds ckn mldh Sub Classes ds Data Members Initialize gksrs gSaA ;kuh ;fn ge mijksDr Code Segment esa fuEukuqlkj ifjorZu djds igys Sub Class ds salary Data Member dks Initialize dj nsa% Scientist(int empID, String empName, float sciSalary) { salary = sciSalary; super(empID, empName); }

rks tkok Compiler gesa fuEukuqlkj Error Message iznku djrk gS] tks gesa crkrk gS fd super() Method dks gesa”kk igys Statement ds :i esa fy[kk tkuk pkfg,A D:\Java\ConstructorInheritance.java:25: cannot resolve symbol symbol : constructor Employee () location: class Employee { ^ D:\Java\ConstructorInheritance.java:27: call to super must be first statement in constructor super(empID, empName); ^ 2 errors

tc ge fdlh Class esa dksbZ Constructor Define ugha djrs gSa] rc Hkh tkok gesa ,d NoArgument Constructor iznku djrk gS] ftls Default Constructor dgrs gSaA blh otg ls geus fcuk fdlh Constructor dks Define fd, gq, Hkh InheritanceDemo Class ds Program esa Employee o Scientist Class ds Objects you o me dks fuEukuqlkj Create dj fy;k Fkk% Employee you = new Employee() Scientist me = new Scientist()

// No-Argument Constructor // No-Argument Constructor

ysfdu tc ge fdlh Hkh Class esa dksbZ Hkh ,slk Constructor cuk nsrs gSa] ftlesa n Arguments gksa] rks Constructor Define djus ds ckn tkok gesa Default Constructor ugha nsrk gSA bl fLFkfr esa Default Constructor Hkh gesa gh cukuk iMrk gSA mnkgj.k ds fy, fiNys Program esa Super Class Employee esa geus ,d 2-Argument Constructor Define fd;k gS] tcfd Sub Class Scientist esa geus ,d 3-Argument Constructor Define fd;k gSA bl fLFkfr esa nksuksa gh Super o Sub Classes dks tkok 305 Any Question or Suggestion, Just Discuss Here...

Java in Hindi Default Constructor iznku ugha djrk gSA blfy, vc ;fn ge fuEukuqlkj Program Create djds Compiler djsa] rks tkok Compiler gesa vxzkuqlkj Error iznku djrk gS% Program class ConstructorInheritance { public static void main(String args[]) { Employee you = new Employee(); Scientist me = new Scientist(); System.out.println("Your Information"); you.showData();

}

}


Output D:\Java\ConstructorInheritance.java:41: cannot resolve symbol symbol : constructor Employee () location: class Employee Employee you = new Employee(); ^ D:\Java\ConstructorInheritance.java:42: cannot resolve symbol symbol : constructor Scientist () location: class Scientist Scientist me = new Scientist(); ^ 2 errors Error ds Output esa ge ns[k ldrs gSa fd nksuksa gh Errors esa Compiler gesa crk jgk gS fd mls Default Constructor ugha fey jgk gSA ;fn ge bl Program dks Hkh Bhd rjg ls Run djokuk pkgrs gSa] rks gesa Super Class o Sub Class nksuksa esa gh ,d No-Argument Constructor Define djuk gksxkA ;kuh gesa nksuksa gh Classes esa fuEukuqlkj ifjorZu djuk

gksxk%

Program class Employee { private int ID; private String name; Employee() {} Employee(int empID, String empName) { ID = empID; name = empName;

// No-Argument Constructor // 2-Argument Constructor


Java in Hindi

}

} public void showData() { System.out.println("\tName : " + name); System.out.println("\tID : " + ID); }

class Scientist extends Employee { private float salary;

}

Scientist() {} Scientist(int empID, String empName, float sciSalary) { super(empID, empName); salary = sciSalary; } public void showData() { super.showData(); System.out.println("\tSalary : " + salary); }

//No-Argument Constructor //3-Argument Constructor

class ConstructorInheritance { public static void main(String args[]) { Employee you = new Employee(); Scientist me = new Scientist(); System.out.println("Your Information"); you.showData(); System.out.println("\nMy Information"); me.showData(); } } Output Your Information Name : null ID : 0 My Information Name : null ID : 0 Salary : 0.0


Java in Hindi pwafd Object Create djus ds fy, geus No-Argument Constructor dk iz;ksx fd;k gS] blhfy, you o me nksuksa gh Objects Un-Initialized gSa vkSj tc tkok esa dksbZ Class Data Member Un-Initialized jgrk gS] rc og Default ekuksa ls Initialize gks tkrk gSA blhfy, bl Program ds Output esa gesa mijksDr Information izkIr gks jgh gSA tc ge fdlh Class dks Extend djrs gSa] rc Extend gksus okyh Sub Class o mldh Super Class ds chp esa “Kind Of” Relationship gksrh gSA ;kuh ge ;s Hkh dg ldrs gSa fd% Sub Class is a “Kind Of” Super Class

vkSj D;ksafd ,d Super Class Object Super Class ds fdlh Hkh nwljs Object dks Refer dj ldrk gS] D;ksafd ,d gh Class ds lHkh Objects leku Type ds ;k leku izdkj ds (“Kind Of”) gksrs gSa] blhfy, Super Class dk Object Sub Class ds Object dks Hkh Refer dj ldrk gSA D;ksafd Sub Class dk Object Hkh ,d izdkj dk (“Kind Of”) Super Class dk Object gh gksrk gSA ysfdu ,d Sub Class dk Object dHkh Hkh viuh Super Class ds Object dks Refer ugha dj ldrk gS] D;ksafd gj Sub Class Type dk Object viuh Super Class Type dk ugha gksrk gSA tcfd gj Super Class Type dk Object viuh Sub Class Type dk Object rks gksrk gh gSA D;ksafd gj Sub Class esa mldh Super Class ds lHkh xq.k gksrs gh gSa] ysfdu gj Super Class esa mldh fdlh Hkh Sub Class ds lHkh xq.k ugha gks ldrs gSaA ;fn ge cgqr gh ljy “kCnksa esa bl Concept dks dgsa rks ge ;s dg ldrs gSa fd ,d Super Class dk Object viuh Sub Class ds fdlh Object dks Refer dj ldrk gS] ysfdu Sub Class dk dksbZ Hkh Object viuh Super Class dks Refer ugha dj ldrk gSA blh rjg ls fdlh Hkh Method esa fdlh Parameter ds :i esa ;fn fdlh Super Class ds Object dh t:jr gks rks ge ml Parameter esa Argument ds :i esa mldh Sub Class ds Object dks Pass dj ldrs gSa] D;ksafd Super Class dk Object Sub Class ds Object dks Refer dj ldrk gSA ysfdu ;fn fdlh Method esa Parameter ds :i esa fdlh Sub Class ds Object dh t:jr gks] rks ge mldh Super Class ds Object dks Parameter esa Argument ds :i esa Pass ugha dj ldrs gSa] D;ksafd Sub Class dk Object Super Class ds Object dks Refer ugha dj ldrk gSA bl Concept dks ge fuEu Program }kjk le> ldrs gSa% Program class Box { double width; double height; double length; Box(double wid, double hei, double len) { width = wid; height = hei; length = len;


Java in Hindi

}

} void getData() { System.out.println("Width = " + width); System.out.println("height = " + height); System.out.println("length = " + length); } double getVolume() { return width * height * length; }

class DerivedBox extends Box { double weight;

}

DerivedBox(double wid, double hei, double len, double wei) { super(wid, hei, len); weight = wei; } public void getData() { super.getData(); System.out.println("Weight = " + weight); }

class DerivedBoxDemonstration { public static void main(String args[]) { Box cpuCabinet = new Box(10, 20, 30); DerivedBox hardDisk = new DerivedBox(1, 2, 3, 4); double cpuCabinetVolume; double hardDiskVolume; cpuCabinetVolume = cpuCabinet.getVolume(); System.out.println("CPU Cabinet Volume = " + cpuCabinetVolume); cpuCabinet.getData();

}

}

cpuCabinet = hardDisk; hardDiskVolume = cpuCabinet.getVolume(); System.out.println("Hard Disk Volume = " + hardDiskVolume); hardDisk.getData();


Java in Hindi Output CPU Cabinet Volume = 6000.0 Width = 10.0 height = 20.0 length = 30.0 Hard Disk Volume = 6.0 Width = 1.0 height = 2.0 length = 3.0 Weight = 4.0 main() Method Class esa geus Box Class dk ,d Object cpuCabinet o DerivedBox Class dk ,d Object hardDisk Create fd;k gSA lkFk gh nksuksa dks Initialize Hkh fd;k gSA fQj double izdkj ds nks Variables cpuCabinet o hardDisk nksuksa Objects ds Volume dks Hold djus ds fy, Define fd;k gSA fQj cpuCabinet dk Volume Calculate djus ds fy, geus Box Class ds Method getVolume() dks cpuCabinet ds lkFk Call fd;k gSA

pwafd cpuCabinet Box Class dk gh Object gS] blfy, ge blds lkFk getVolume() Method dks Call dj ldrs gSaA fQj geus Box Class ds Object cpuCabinet ds Dimensions izkIr djus ds fy, getData() Method dks Call fd;k gSA vxys Statement esa geus Box Class ds Object cpuCabinet esa Box Class dh Sub Class DerivedBox Class ds Object hardDisk dk Reference fuEukuqlkj Statement }kjk iznku fd;k gS% cpuCabinet = hardDisk;

ge ,slk blfy, dj ldrs gSa D;ksafd DerivedBox Class Box Class ds izdkj (“Kind Of”) dh gh gSA tc ge ,slk djrs gSa] rc okLro esa hardDisk Object dks cpuCabinet Object }kjk Refer dj ldrs gSa vkSj hardDisk Object ds fy, tks fd Box Class dh Sub Class dk Object gSa] Box Class ds Methods dks Call dj ldrs gSaA pwafd geusa Sub Class esa getVolume() uke dk Method Create ugha fd;k gS] fQj Hkh ge Super Class Box ds getVolume() Method dk iz;ksx djds Sub Class DerivedBox ds Object dk Volume Hkh Kkr dj ldrs gSa] tSlkfd bl Program ds vxys Statement esa fd;k x;k gSA cpuCabinetVolume = cpuCabinet.getVolume(); cpuCabinet = hardDisk; hardDiskVolume = cpuCabinet.getVolume();

bu nksuksa Statement esa ge ns[k ldrs gSa fd geus nksuksa gh ckj cpuCabinet ds Reference esa gh getVolume() Method dks Call fd;k gSA ysfdu tc igyh ckj cpuCabinet ds fy, getVolume() Method dks Call djrs gSa] rc Box Class dk getVolume() Method Super Class Box ds Object cpuCabinet dk Volume Calculate djrk gS] D;ksafd bl le; cpuCabinet Object esa Box Class ds Object dk Reference gSA


Java in Hindi ysfdu tSls gh ge Box Class ds cpuCabinet Object esa DerivedBox Sub Class ds hardDisk Object dk Reference nsrs gSa] cpuCabinet uke dk Super Class dk Object Sub Class ds Object dks Refer djus yxrk gSA blfy, vc fQj ls tc ge bl cpuCabinet Object ds lkFk Super Class ds getVolume() Method dks Call djrs gSa] rks bl ckj cpuCabinet Object Box Class ds Object dh Volume Calculate djus ds ctk; DerivedBox Class ds Object dk Volume Calculate djrk gSA bl Program esa ge ns[k ldrs gSa fd geus Super Class Box ds Object cpuCabinet esa Sub Class DerivedBox ds Object dk Reference Store fd;k gSA ge ,slk dj ldrs gSa] D;ksafd Sub Class gesa”kk “Kind Of” Super Class gksrk gSA ysfdu ;fn ge bl Statement dks mYVk djsa] ;kuh Sub Class ds Object esa Super Class ds Object dk Reference iznku djsa] rks tkok Compiler gesa fuEukuqlkj Compile Time Error nsrk gS% D:\Java\DerivedBoxDemonstration.java:59: incompatible types found : Box required: DerivedBox hardDisk=cpuCabinet; ^ 1 error

tkok Compiler gesa ;s Error blfy, nsrk gS] D;ksafd Super Class dHkh Hkh “Kind Of” Sub Class ugha gksrh gS] cfYd Super Class Sub Class dk ,d Part gksrk gSA blfy, Super Class o Sub Class ds chp “Has A “ o “Part Of “ dh Relationship cu tkrh gSA pwafd ge Super Class ds Object ls fdlh Hkh Sub Class Object dks Refer dj ldrs gSa vkSj ,d Super Class Object ls gh fofHkUu izdkj dh Sub Classes ds Methods dks Call dj ldrs gSa] blfy, tkok esa ;s Process Polymorphism dh lqfo/kk iznku djrk gSA

Multilevel Hierarchy

tkok esa ge fdlh Derive dh xbZ Sub Class dks fQj ls Derive dj ldrs gSaA tc ge fdlh Derive dh xbZ Sub Class dks fQj ls Derive djrs gSa] rks bl Process dks Multilevel Hierarchy dgk tkrk gSA mnkgj.k ds fy, tkok dh lcls Top Level dh Class Object Class gSA Object Class ls awt Class dks Inherit fd;k x;k gSA fQj awt Class ls Component Class dks Derive fd;k gSA fQj Component Class ls Container Class dks Derive fd;k gSA fQj Container Class ls Panel Class dks Derive fd;k gS vkSj vUr esa Panel Class ls Applet Class dks Derive fd;k gSA bl rjg ls ge Applet Class dh Multilevel Hierarchy dks le> ldrs gSaA

Constructor Calling Convention

tkok esa tc ge fdlh Class dks Derive djrs gS] rks Super Class dk Constructor dHkh Hkh Sub Class esa ugha vkrk gSA blfy, gesa gesa”kk Sub Class ds Constructor esa Super Class ds Constructor dks Call djuk iMrk gSA tkok Multiple Hierarchy dks Support djrk gSA blfy, ge pkgs fdlh Hkh Level dh Hierarchy dh Class dks Inherit djsa] ml Inherited Class ds Object Create djrs gh Sub Class dk Constructor Execute gks tkrk gS vkSj


Java in Hindi Derived Class dk Constructor Execute gksrs gh Super Class ds Constructor dks Execute djrk gSA

;fn geus Sub Class esa dksbZ Constructor ugha cuk;k gS] rks Class dk Default ;k NoArgument Constructor Execute gksrk gS vkSj Derived Class dk Constructor Base Class ;k Super Class ds Default Constructor dks Execute dj nsrk gSA ;kuh lkjka”k esa dgsa rks ge Hierarchy esa pkgs ftl Level dh Class dk Object Create djsa] gesa”kk Hierarchy ds Top Level Class dk Constructor lcls igys Execute gksrk gS vkSj fQj Øe ls uhps dh Classes ds Constructors Execute gksrs gSaA ;fn fdlh Super Class esa dksbZ n Argument Constructor gks rks gesa Sub Class esa Hkh n Argument Constructor cukuk t:jh gks tkrk gS] tcfd ;fn Sub Class esa dksbZ n Argument Constructor gks rks Super Class esa n Argument Constructor dk gksuk t:jh ugha gksrk gSA tc ,slh fLFkfr gksrh gS] rc Sub Class dk rks n Argument Constructor Execute gksrk gS ysfdu Super Class dk No-Argument Constructor Execute gks tkrk

gSA

fdlh Sub Class ds Constructor esa Super Class ds Constructor dks Call djus ds fy, gesa super() Method dks Call djuk gksrk gSA ysfdu ;fn ge fdlh Sub Class Constructor esa mldh Super Class ds Constructor dks Call uk djsa] rks Hkh Super Class dk Default Constructor rks Execute gksrh gh gS] lkFk gh og Sub Class ds Constructor ls igys Execute gksrk gSA

Dynamic Method Dispatch – The Run Time Polymorphism

Method Overriding tkok dk ,d cgqr gh egRoiw.kZ Concept gS] D;ksafd blds iz;ksx }kjk gesa tkok esa Dynamic Method Dispatch dh lqfo/kk izkIr gksrh gS] tks fd tkok dk lcls egRoiw.kZ o Powerful Concept gSA Dynamic Method Dispatch ,d ,slk rjhdk gS] tks Program ds Runtime esa ;s r; djrk gS fd fdlh Object ds Reference esa dkSulk Method Execute gksxk uk fd Compile Time esaA Dynamic Method Dispatch blhfy, egRoiw.kZ gS D;ksafd ;gh og rjhdk gS ftlls tkok Run Time Polymorphism dks Implement djrk gSA

geus igys Hkh crk;k Fkk fd ,d Super Class dk Object ml Class dh lHkh Sub Classes ds Objects dks Refer dj ldrk gSA tkok bl Concept dks Use djds Program ds Run Time esa ;s r; dj ldrk gS fd mls fdl Method dks Call djuk gSA pfy,] Run Time Polymorphism dh bl rduhd dks le>us dh dksf”k”k djrs gSaA tc fdlh Super Class Object ds Reference esa fdlh Overridden Method dks Call fd;k tkrk gS] rc tkok dks ;s r; djuk iMrk gS fd Object ds fy, bl Overridden Method ds Super Class ds Method dks Call djuk gS ;k Sub Class ds Overridden Method dks Call djuk gSA ;s r; djus ds fy, tkok ml Object dh Class dk irk yxkrk gS vkSj ;s Identify djrk gS fd Overridden Method dks Call djus okyk og Object fdl Class dk gSA ;fn Object Sub Class dk gksrk gS] rks tkok Sub Class ds Overridden Method dks Call dj ysrk gS] tcfd ;fn Object Super Class dk gksrk gS] rks tkok Super Class ds Overridden Method dks Call dj ysrk gSA tkok ;s fu.kZ; Program ds Run Time esa ysrk gS]


Java in Hindi blfy, bl izfØ;k dks Dynamic Method Dispatch ;k Run time Polymorphism dgk tkrk gSA pwafd ,d Super Class Object viuh fdlh Hkh Sub Class ds Object dks Refer dj ldrk gS] blfy, ge Super Class ds fdlh Hkh Object dks mlh Class dh fdlh Hkh Sub Class ds Object dk Reference Assign dj ldrs gSaA bl fLFkfr esa tc ge Super Class ds Object ds fy, fdlh Overridden Method dks Call djsaxs] rc tkok ml Super Class ds Object ds Reference ls ;s irk yxk ysxk fd mlesa fdl Sub Class Object dk Reference gSA Super Class ds bl Object esa ftl Sub Class ds Object dk Reference gksxk] tkok mlh Sub Class ds Overridden Method dks Call dj ysxkA bl izdkj dh fLFkfr esa ge gekjs Program esa ,d gh izdkj dk Statement fy[krs gSa] ysfdu gj Statement Run Time esa ;s r; dj ysrk gS fd mls fdl Class ds Overridden Method dks Call djuk gSA blfy, bl izfØ;k dks Polymorphism dgk tkrk gSA Polymorphism dh bl izfØ;k dks ge fuEukuqlkj Program }kjk le> ldrs gSa% Program // File Name: DynamicMethodDispatch.java class TopClass { void callme() { System.out.println("callme Method Called from the TopClass"); } } class MiddleClass extends TopClass { void callme() // Overridden callme() Method { System.out.println("callme Method Called from the MiddleClass"); } } class BottomClass extends MiddleClass { void callme() // Overridden callme() Method { System.out.println("callme Method Called from the BottomClass"); } } class DynamicMethodDispatch { public static void main(String args[]) { TopClass topObject = new TopClass(); MiddleClass middleObject = new MiddleClass(); BottomClass bottomObject = new BottomClass();

// TopClass Object // MiddleClass Object // BottomClass Object


Java in Hindi TopClass reference = new TopClass(); reference = topObject; reference.callme();

// TopClass Object

// reference Refers to TopClass Object // Calls TopClass's callme() Overridden Method

reference = middleObject; // reference Refers to MiddleClass Object reference.callme(); // Calls MiddleClass's callme() Overridden Method

}

}

reference = bottomObject; // reference Refers to BottomClass Object reference.callme(); // Calls BottomClass's callme() Overridden Method

Output callme Method Called from the TopClass callme Method Called from the MiddleClass callme Method Called from the BottomClass

bl Program esa ge ns[k ldrs gSa fuEu Statement dks Program esa rhu ckj Use fd;k x;k gS] ysfdu rhuksa gh ckj ,d vyx callme() Method Execute gqvk gS] ftUgsa ge Output esa ns[k ldrs gSa% reference.callme();

bl Statement ls gj ckj vyx Class dk Overridden callme() Method blfy, Execute gqvk gS] D;ksafd gj ckj bl Statement ls igys Øe ls fuEukuqlkj ,d Statement fy[kdj Super Class ds topObject dks Sub Class ds Object dk Reference Assign fd;k x;k gS% reference = topObject; // reference Refers to TopClass Object reference = middleObject; // reference Refers to MiddleClass Object reference = bottomObject; // reference Refers to BottomClass Object

vkSj pwafd tkok Compiler mlh Object dh Class ds callme() Method dks Call djrk gS] ftldh Class ds Object dk Reference Super Class ds Object reference esa gksrk gSA blfy, gj ckj reference.callme() Statement ,d vyx Class ds callme() Method dks Call dj ysrk gSA “C++” esa ;gh dke Virtual Functions djrs gSaA vc loky ;s iSnk gksrk gS fd tkok esa bl Method Overridden Concept dh t:jr D;k gS\ rks bldk tokc ;s gS fd Method Overridden djus ls gesa tkok esa Run Time Polymorphism dh lqfo/kk izkIr gks tkrh gSA Polymorphism fdlh Hkh Object Oriented Programming Language dk ,d cgqr gh egRoiw.kZ fgLlk gksrk gS vkSj gj Object Oriented Programming Language esa Polymorphism dk Support djuk blfy, t:jh gksrk gS] D;ksafd Polymorphism ;s lqfo/kk nsrk gS fd fdlh General Class ds ftrus Hkh Methods mldh lHkh Derived ;k Sub


Java in Hindi Classes ds fy, Common gks ldrs gSa] mu lHkh Methods dks Super Class esa Define fd;k tk ldrk gSA Polymorphism }kjk iznku dh tkus okyh bl lqfo/kk ds dkj.k gesa mu lHkh dkeksa dks djus ds fy, tks fd fdlh Super Class dh lHkh Sub Classes ds fy, Common gksa] gj Sub Class esa vyx ls Methods dks Define djus dh t:jr ugha jg tkrh gS] cfYd lHkh izdkj dh Sub Classes ds fy, tks Common Methods gksrs gSa] mUgsa Super Class esa gh Define dj fy;k tkrk gS vkSj tc Hkh fdlh Sub Class esa Super Class ds ml Method dks Access djus dh t:jr gksrh gS] Polymorphism ds Concept ds vk/kkj ij Super Class ds Object esa Sub Class ds Object dk Reference Assign djds Sub Class ds Object ds fy, Super Class ds ml Common Method dks Call dj fy;k tkrk gSA

tkok esa Polymorphism dks Best rjhds ls Apply djuk bl le> ij fuHkZj djrk gS fd Super Class o Sub Class vkil esa feydj ,d izdkj dh Hierarchy Create djrs gSa] tks fd Top Level ls Lower Level dh rjQ vkrs&vkrs General Classes ls Specialized Classes esa Convert gksrs pys tkrs gSaA ;fn Super Class dks vPNh rjhds ls Use fd;k tk,] rks ,d Super Class mldh lHkh Sub Classes dks ;s lqfo/kk nsrk gS fd os Super Class ds lHkh Elements dks Directly Access dj ldrs gSaA Super Class esa mu Methods dks Hkh igys ls gh Define fd;k tk pqdk gksrk gS ftUgsa Derived Classes dks Implement djuk t:jh gksrk gSA Polymorphism Sub Classes dks ;s Flexibility iznku djrk gS fd muesa muds [kqn ds Methods dks Define fd;k tk ldsA bl rjg ls ;fn ge lkjka”k ns[ksa rks ge dg ldrs gSa fd Inheritance dks Overridden Methods ds lkFk Combine djds ,d Super Class ,sls Methods dks Define dj ldrk gS] ftUgsa ml Super Class dh lHkh Classes Common :i

ls mi;ksx esa ysus esa l{ke gksrh gSaA

Dynamic ;k Run Time Polymorphism Object Oriented Programming ds Design dk ,d Most Powerful Mechanism gS] ftlds dkj.k ge lqjf{kr rjhds ls ,d ckj Create fd, x, Codes dks ckj&ckj Reuse djus esa l{ke gks ikrs gSaA OOPS }kjk iznku dh xbZ ;s {kerk ftlls ubZ Classes ds Objects igys ls Exists Code Library ds Methods dks fcuk Recompile fd, gq, fQj ls Call dj ldrs gSa] Object Oriented Programming Design dh ,d Programmer dks feyus okyh ,d cgqr gh tcjnLr lqfo/kk gSA

pfy,] Polymorphism dk ,d vkSj mnkgj.k ns[krs gSa] ftlesa Method Overriding dk iz;ksx fd;k x;k gSA vxys Program esa Figure uke dh ,d Super Class gS] ftlesa fofHkUu 2-D Objects ds Dimension Store gksrs gSaA blesa area() uke dk ,d Method Hkh Define fd;k x;k gS] tks Object ds Area dks Calculate djrk gSA bl Program esa bl Figure Class ls nks Sub Classes Rectangle o Triangle Derive dh xbZ gSaA ;s nksuksa Sub Classes Super Class ds area() Method dks Override djrs gSa] rkfd ;s Method Øe ls Rectangle o Triangle nksuksa dk Area Return dj ldsA Program // File Name: PolymorphismArea.java class Figure {


Java in Hindi double dim1, dim2;

}

Figure(double dimension1, double dimension2) { dim1 = dimension1; dim2 = dimension2; } double area() { System.out.println("\nArea of Figure is undefined "); return 0; }

class Rectangle extends Figure { Rectangle(double dimension1, double dimension2) { super(dimension1, dimension2); } double area() // Override area() for Rectangle Class { System.out.println("\nInside Area for Rectangle : "); return dim1 * dim2; } } class Triangle extends Figure { Triangle(double dimension1, double dimension2) { super(dimension1, dimension2); } double area() // Override area() for Right Triangle { System.out.println("\nInside Area for Triangle : "); return dim1 * dim2 / 2; } } class PolymorphismArea { public static void main(String args[]) { Figure newFigure = new Figure(10,10); Rectangle newRectangle = new Rectangle(6,7); Triangle newTriangle = new Triangle(12,23); Figure referenceFigure;


Java in Hindi referenceFigure = newRectangle; System.out.println("Area is " + referenceFigure.area()); referenceFigure = newTriangle; System.out.println("Area is " + referenceFigure.area());

}

}

referenceFigure = newFigure; System.out.println("Area is " + referenceFigure.area());

Output Inside Area for Rectangle : Area is 42.0 Inside Area for Triangle : Area is 138.0 Area of Figure is undefined Area is 0.0

Abstract Classes

dbZ ckj ,slh fLFkfr;ka gksrh gSa tc ge tks Super Class cukrs gSa og dsoy ,d General Class ds :i esa gh Use gks ldrh gSA ,slh Class ds Direct Object Create ugha fd, tk ldrs gSaA ,slh Class ,d rjg ls v/kwjh Class gksrh gS] ftlesa Declare fd, x, lHkh Methods dks Define ;k Implement ugha fd;k x;k gksrk gSA ,d ,slh General Class ftlds lHkh xq.kksa dks mldh lHkh Sub Classes Share djsa] ysfdu Lo;a ml General Class dk Object uk Create fd;k tk lds] bl izdkj dh Class dks Abstract Class dgrs gSaA ,d Abstract Class dks gesa gesa”kk Inherit djuk gh gksrk gS] D;ksafd bl izdkj dh Class esa fofHkUu izdkj ds Methods dks Declare rks fd;k tkrk gS] ysfdu mUgsa Implement ;k Define ugha fd;k tkrk gSA cfYd bUgsa mu Sub Classes esa Implement djus ds fy, NksM fn;k tkrk gS] ftUgsa bl izdkj dh Abstract Classes ls Inherit fd;k tkrk gSA Abstract Class ,d ,slh Class gksrh gS tks mldh lHkh Sub Classes dh Common Properties o Behaviors ;kuh Common Attributes o Methods dks Describe djrh gSA pwafd Abstract Class gesa”kk lHkh Derived Classes dh Common Things dks Describe djrh gS] blfy, blds Lora= Objects ugha Create fd, tk ldrs gSaA D;ksafd Objects gesa”kk Special Classes ds Create gksrs gSa vkSj lHkh Sub Classes ds Common Members dks Represent djus okyh Class Hkh ,d Common ;k General Class gksrh gSA

mnkgj.k ds fy, Shape ,d General Class gSA blds Direct Object Create ugha fd, tk ldrs gSa] cfYd ;fn gesa Shape Object Create djuk gks] rks ge Rectangle, Triangle, Circle vkfn Shape Object Create dj ldrs gSaA ysfdu ;fn ge Shape Class dk Object Create djuk pkgsa] rks ge ,slk ugha dj ldrs gSaA D;ksafd Shape Loa; dqN ugha gksrk gSA


Java in Hindi lkekU;r;k Abstract Classes rc cukbZ tkrh gSa] tc dksbZ Super Class Lo;a fdlh Meaningful Object dks Represent ugha djrk gS] cfYd fdlh Group Of Objects ds Common Features dks Represent djrk gSA gekjs fiNys mnkgj.k dh Super Class ,d Abstract Class gS vkSj gesa blds Object Create djus dh t:jr ugha gS] D;ksafd blds Objects Meaningful ugha gSaA ;fn ge Figure Class dk dksbZ Object Create djrs gSa] rks Figure Class dk Object Create djus dk dksbZ Meaning ugha gS D;ksafd Figure Loa; dqN ugha gSA ysfdu fQj Hkh ,d Class User fdlh Abstract Class ds Objects Create dj ldrk gSA bl fLFkfr esa ;fn og pkgs rks Abstract Class ds Object ds Reference esa area() Method dks Hkh Call dj ldrk gSA ysfdu pwafd Abstract Class Figure Loa; fdlh Actual Object dks Represent ugha djrk gS] blfy, blds Object ds fy, area() Method dks Call djus dk dksbZ Meaning ugha gSA blhfy, bl Class ds area() Method esa geus ,d Message gh fy[kk gSA pwafd ge tkurs gSa fd fdlh Hkh Abstract Class ds Object Create djus dk dksbZ eryc ugha gksrk gS] fQj Hkh ,d Class User fdlh Abstract Class ds Object Create dj ldrk gSA blfy, ;fn User fdlh Abstract Class ds Object Create djs vkSj User dks dksbZ Error Message izkIr gks] blls csgrj rks ;gh gS fd User dHkh fdlh Abstract Class ds Object Create gh uk dj ldsA ;s lqfo/kk ge tkok ds Abstract Methods ls izkIr dj ldrs gSaA fdlh Class dks Abstract cukus ds fy, gesa Abstract Class esa Define fd, tkus okys lHkh Methods dks Abstract Keyword ds lkFk Declare djuk gksrk gSA tc ge fdlh Class ds lHkh Methods dks Abstract Declare dj nsrs gSa] rks tkok ml Class dks Abstract Class eku ysrk gS vkSj ,d Class User dks ml Abstract Class ds Object Create ugha djus nsrk gSA bl fLFkfr esa User ;fn fdlh Abstract Class ds Object Create djrk gS] rks tkok Compiler mls ,d Error Message iznku djrk gSA fdlh Method dks Abstract Class esa Abstract Declare djus ds fy, gesa fuEukuqlkj Syntax dk iz;ksx djuk iMrk gS% abstract Return_Type Method_Name(Parameter_List);

bl Syntax esa ge ns[k ldrs gSa fd bl Method dh dksbZ Body ugha gS] cfYd Parenthesis ds ckn Semicolon dk iz;ksx djds Method dks Terminate fd;k x;k gSA ftl fdlh Class esa ,d ;k ,d ls vf/kd Abstract Methods gksrs gSa] ml Class dks Hkh gesa Abstract Declare djuk t:jh gks tkrk gSA Class dks Abstract djus ds fy, gesa Class dks fuEukuqlkj Define djuk gksrk gS% abstract class shape { abstract void area(); }

bl izdkj ls tc ge fdlh Class dks Abstract dj nsrs gSa] rc ml Class ds Objects dks new Operator dk iz;ksx djds Directly Create ugha fd;k tk ldrk gSA Abstract Classes o Methods By Default Public gksrs gSa] blfy, buds lkFk fdlh Access Specifier dh


Java in Hindi t:jr ugha gksrh gSA fdlh lkekU; Method dh rjg gh ge Abstract Constructor o Abstract Static Method Create ugha dj ldrs gSaA dksbZ Hkh Class tks fd fdlh Abstract Class dks Derive djrk gS] mlesa bu Abstract Methods dks Implement djuk t:jh gksrk gSA ;fn ge ml Derived Class esa lHkh Methods Implement uk djsa] rks og Derived Class Hkh rc rd Abstract Class cuh jgrh gS] tc rd ge mldh Super Class ds lHkh Methods dks Implement uk dj nsaA pfy,] ,d mnkgj.k }kjk ge Abstract Class o Abstract Method dks le>us dh dksf”k”k djrs gSa% Program // File Name: AbstractClassNMethod.java abstract class SuperClass // Abstract Class { abstract void abstractMethod(); // Abstract Method

}

void SimpleMethod() { System.out.println("Abstract Super Class Method CALLED"); }

class SubClass extends SuperClass { void abstractMethod() { System.out.println("Implemented Super Class Method CALLED"); } } class AbstractClassNMethod { public static void main(String args[]) { SubClass objSubClass = new SubClass();

}

}

objSubClass.SimpleMethod(); objSubClass.abstractMethod();

Output Abstract Super Class Method CALLED Implemented Super Class Method CALLED main() Program esa ge ns[k ldrs gSa fd geus Abstract Super Class dk dksbZ Object Create ugha fd;k gSA ;fn ge ,slk djus dh dksf”k”k djrs gSa] rks tkok Compiler gesa ,slk djus Hkh ugha nsrk gSA fdlh Abstract Class ds lHkh Methods Abstract gksa] ,slk t:jh ugha gksrk gSA ge fdlh Abstract Class esa Simple Methods Hkh Define dj ldrs gSa vkSj bl 319 Any Question or Suggestion, Just Discuss Here...

Java in Hindi Simple Method dks main() Method Program esa fdlh Sub Class Object ds lkFk Directly Use Hkh dj ldrs gSa] tSlkfd geus bl Program esa fd;k gSA

gkykafd Abstract Classes ds Object Create ugha fd, tk ldrs gSa] ysfdu fQj Hkh Super Class dk Reference Create fd;k tk ldrk gS] D;ksafd tkok esa Run Time Polymorphism dks Super Class ds Reference }kjk gh Implement fd;k tk ldrk gSA blfy, ;s t:jh gksrk gS fd ge fdlh Abstract Super Class ds Hkh Reference Create dj ldsa] tks ml Abstract Class dh Sub Classes ds Objects dks Refer dj ldsA pwafd geus tks Figure Program cuk;k Fkk] mlesa Hkh Super Class ds Object Create djus dk dksbZ Meaning ugha gSA blfy, ge ml iwjs Program dks Abstract Class ds :i esa fuEukuqlkj Modify dj ldrs gSa% Program // File Name: AbstractClass.java abstract class Figure { double dim1, dim2; Figure(double dimension1, double dimension2) { dim1 = dimension1; dim2 = dimension2; } abstract double area();

} class Rectangle extends Figure { Rectangle(double dimension1, double dimension2) { super(dimension1, dimension2); }

}

double area() // Implementing of Super Class’s Abstract Method { System.out.println("\nInside Area for Rectangle : "); return dim1 * dim2; }

class Triangle extends Figure { Triangle(double dimension1, double dimension2) { super(dimension1, dimension2); }


Java in Hindi

}

double area() // Implementing of Super Class’s Abstract Method { System.out.println("\nInside Area for Triangle : "); return dim1 * dim2 / 2; }

class AbstractClass { public static void main(String args[]) { // Figure newFigure = new Figure(10,10); Rectangle newRectangle = new Rectangle(6,7); Triangle newTriangle = new Triangle(12,23); Figure referenceFigure;

// Object Created // Object Created // Object Created // Reference Created

referenceFigure = newRectangle; System.out.println("Area is " + referenceFigure.area()); referenceFigure = newTriangle; System.out.println("Area is " + referenceFigure.area());

}

// referenceFigure = newFigure; // System.out.println("Area is " + referenceFigure.area()); }

Output Inside Area for Rectangle : Area is 42.0 Inside Area for Triangle : Area is 138.0

tkok esa fdlh Hkh Class ds Object esa gesa”kk fdlh uk fdlh Actual Memory Block dk Reference Store gksrk gSA bldk eryc ;s gksrk gS fd tkok esa fdlh Hkh Class dk Object Lo;a fdlh Memory Block dk uke ugha gksrk gS] cfYd fdlh Memory Block ds Address dk Reference bl Object esa Hold gksrk gSA ;kuh tkok esa rc rd dksbZ Actual Object Create ugha gksrk gS] tc rd fd ge new Operator dk iz;ksx djds Object Create uk djsaA tc ge new Operator }kjk dksbZ Memory Block Create djrs gSa] rc Created Memory Block dk Reference gh ml Class ds Object esa Store gksrk gSA tcfd Abstract Classes ,slh Classes gSa] ftuds Object Create ugha fd, tk ldrs gSa] ysfdu Reference rks Abstract Classes ds Hkh Create fd, tk ldrs gSa vkSj bl Program esa geus Figure uke dh Abstract Class dk Reference gh main() Method esa Create fd;k gSA blfy, ;s Program iwjh rjg ls dke djrk gS vkSj gesa mfpr Output nsrk gSA


Java in Hindi bl Program esa geus dqN Lines dks Comment cuk;k gSA ;fn ge Program dh igyh Line dks Normal dj nsa] rks ;s Line Figure Class dk Object Create djsxk] tks fd lEHko ugha gSA blfy, Error Generate gksxk] vkSj pwafd Figure Class dk Object Create ugha gks ldrk gS] blh otg ls ge Figure Class ds fdlh Object ds fy, fdlh Hkh Method dks Call ugha dj ldrs gSaA blhfy, Program dh vfUre nks Lines ds Code dks Hkh Comment cuk;k gSA

Final Classes

final tkok dk ,d ,slk Keyword gS] ftldk iz;ksx fdlh dke dks Finalize djus ds fy, fd;k tkrk gSA ftl izdkj ls Abstract Classes ,slh Classes gksrh gSa] ftUgsa Inherit djuk gh iMrk gS] mlh rjg ls dqN Level dh Hierarchy ds ckn dqN ,slh Classes Hkh cu tkrh gSa] ftUgsa fdlh Hkh gkyr esa Inherit ugha fd;k tkuk pkfg, gksrk gSA

tc gesa ,slh Derive dh tkus okyh fdlh Class dks Inheritance Hierarchy dh vfUre Class cukuk gks vkSj blh Class ij Hierarchy dk vUr djuk gks] rks bl izdkj dh Class dks gesa Final Class ds :i esa Derive djuk gksrk gSA ftl rjg ge fdlh Abstract Class ds Object Create ugha dj ldrs gSa mlh rjg ls ge fdlh Final Class dks Inherit ;k Derive djds ubZ Class ugha cuk ldrs gSaA blh rjg ls tc ge ;s pkgrs gSa fd fdlh Super Class dk dksbZ Method dHkh Hkh fdlh Hkh Derived Class esa Override uk fd;k tk lds] rks ge ml Method dks Current Class dh Super Class esa Final Define dj nsrs gSaA fdlh Method dks Final Define djus ds fy, gesa dsoy ml Method ds Return Type ls igys final Keyword dk iz;ksx djuk iMrk gSA tc ge fdlh Method dks final Define dj nsrs gSa vkSj ml Class dks Derive djrs gSa] rks Derived Class esa ml final Define fd, x, Method dks Override ugha fd;k tk ldrk gSA bl izfØ;k dks ge fuEukuqlkj Code Segment }kjk le> ldrs gSa% // File Name: AbstractClass.java class Figure { final double area() { // Other Statements } } class Rectangle extends Figure { double area() // Could not Override final method { } }


Java in Hindi bl Code Segment esa Sub Class esa Super Class ds final Method area() dks Override djus dh dksf”k”k dh tk jgh gS] tks fd lEHko ugha gSA bl Code Segment dks Run djus ij Error Generate gksxkA // File Name: AbstractClass.java final class Figure { double area() { // Other Statements } } class Rectangle extends Figure // Could not Inherit final Class { }

bl Code Segment esa Super Class dks Inherit fd;k tk jgk gS] tks fd lEHko ugha gSA D;ksafd Super Class ,d Final Class gSA blfy, bl Code Segment dks Run djus ij Error Generate gksxkA ftl rjg ls ge fdlh Class esa Data Member ds :i esa fofHkUu izdkj ds Data Type ds Variables ,d Class esa Compose djrs gSa] mlh rjg ls ge fdlh Class esa Data Member ds :i esa fdlh nwljh Class ds Objects dks Hkh Compose dj ldrs gSaA fiNys v/;k; rd geus Applet Class dks Derive djds vyx&vyx rjg ds Programs Create fd, FksA mlh rjg ls ge viuh Lo;a dh Classes cuk dj mUgsa Hkh fQj ls Inheritance ds Concept dk iz;kssx djds fQj ls ckj&ckj Use dj ldrs gSaA tkok esa ftruh Hkh Classes gSa] mUgsa Object uke dh ,d Class ls Inherit fd;k x;k gSA blfy, Object Class tkok dh fdlh Hkh vU; Class dh Top Level Super Class gSA blfy, ge Object Class ds fdlh Hkh Object ls fdlh Hkh vU; Class dks Refer dj ldrs gSaA D;ksafd Array dks Hkh tkok esa Classes dh rjg gh Implement fd;k tkrk gS] blfy, Object Class ds Objects fdlh Array dks Hkh Refer dj ldrs gSaA ,d Object Class esa fuEu Methods gksrs gSa] tks tkok dh lHkh vU; Classes esa Default :i ls miyC/k gks tkrs gSa] D;ksafd tkok dh lHkh vU; Classes Object Class ls gh Derived gSA Object clone() ;s Method ,d u;k Object Create djds Return djrk gS vkSj Return gksus okyk Object mlh Object dk Clone gksrk gS] ftlds Reference esa bl Method dks Call

fd;k tkrk gSA

boolean equals(Object obj) ;s Method ;s Check djrk gS fd Argument ds :i esa Pass fd;k x;k Object o bl Method dks Call djus okyk Object nksuksa leku Objects gSa ;k ughaA ;fn nksuksa leku Object gksrs gSa] rks ;s Method true Return djrk gS vkSj ;fn nksuksa Objects leku ugha gksrs gSa rks ;s Method false Return djrk gSA 323 Any Question or Suggestion, Just Discuss Here...

Java in Hindi void finalize() ;s Method fdlh Unused Object ds Recycle gksus ls igys Call gksrk gSA Class getClass() ;s Method Program ds Run Time esa fdlh Object dh Class Return djrk gSA int hashCode() ;s Method ml Object ds Hash Code dks Return djrk gS] ftlds Reference esa bl Method dks Call fd;k tkrk gSA void notify() ;s Method Invoke djus okys fdlh Object ij Wait dj jgs fdlh Thread ds Execution dks Resume djus ;kuh fQj ls Execute djus dk dke djrk gSA void notifyAll() ;s Method Invoke djus okys fdlh Object ij Wait dj jgs lHkh Threads ds Execution dks Resume djus ;kuh fQj ls Execute djus dk dke djrk gSA String toString() ;s Method Object dks Describe djus okyk ,d String Return djrk gSA void wait() void wait(long milliseconds) void wait(long milliseconds, int nanoseconds) ;s rhuksa gh Methods Execution ds fdlh nwljs Thread ij Wait djrs gSaA getClass(), notify(), notifyAll() o wait() bu pkjksa Methods dks Final Declare fd;k x;k gSA buds vykok ckdh ds Methods dks ge Override dj ldrs gSaA toString() Method ,d String Return djrk gS] tks fd ml Object dh Description gksrk gS ftlds Reference esa bl Method dks Call fd;k x;k gSA lkFk gh tc ge println() Method dk iz;ksx djds fdlh Object dks Output esa Hkstrs gSa] rc ;s Method Automatically Call gks tkrk gSA


Java in Hindi

Java Interface For

Multiple Inheritance


Java in Hindi Java Interfaces – Multiple Inheritances

lkekU;r;k ,d Abstract Class esa dqN Methods dks Abstract Declare fd;k tkrk gS] tcfd dqN Methods dks lkekU; Method gh j[kk tkrk gSA ;fn ge dksbZ ,slh Abstract Class Define djsa] ftlesa lHkh Methods Abstract gksa] rks okLro esa ge ,d ,slh Class Create dj jgs gksrs gSa] ftls lEHkor;k Interface dgk tk ldrk gSA ;kuh Interface ,d iwjh rjg ls Abstract Class gksrh gS] ftlesa fdlh Hkh Method dks Implement ugha fd;k x;k gksrk gSA ge fdlh Interface dks Hkh Bhd mlh rjg ls Derive dj ldrs gSa] ftl rjg ls fdlh vU; lkekU; Class dks Derive djrs gSaA Interface Hkh ,d lkekU; Class dh rjg gh Class gksrh gSA ;kuh blesa Hkh Data Members o Methods gksrs gSaA ysfdu blds Data Members gesa”kk static final ;kuh Constants gksrs gSa] tcfd blds lHkh Methods iwjh rjg ls Unimplemented gksrs gSaA blds vykok ,d Interface dh tks nwljh lcls cMh fo”ks’krk gksrh gS og ;s gksrh gS fd tkok dh dksbZ Hkh Class ,d ls T;knk ;kuh Multiple Interfaces dks Implement dj ldrk gSA Interface dh bl fo”ks’krk ds dkj.k tkok dh Multiple Inheritance dh deh dh Hkh iwfrZ gks tkrh gSA ;kuh gkykafd tkok Directly Multiple Inheritance dks Support ugha djrk gS] ysfdu Interface dks tkok esa Multiple Inheritance ds Alternate ds :i esa Use fd;k tkrk gS] ftlls tkok esa Multiple Inheritance dh deh ugha yxrh gSA pwafd ,d Class ,d ls T;knk Interfaces dks Implement dj ldrk gS] blfy, og Class Interfaces esa Declare fd, x, lHkh Classes ds Methods dks Implement djds Interface esa Declared lHkh Methods dh Functionality Provide djus esa l{ke gks tkrk gSA gkykafd ;s rjhdk iwjh rjg ls Multiple Inheritance dh lHkh lqfo/kk,a iznku ugha dj ikrk gS] fQj Hkh ;s tkok dk ,d cgqr gh mi;ksxh Feature gS vkSj ;s Feature ;gh gS tks tkok dh Abstract Classes dks Interfaces ls Separate djrk gSA tkok gesa ;s lqfo/kk nsrk gS fd ge fofHkUu Interfaces dks ;kuh Public Methods dks fcuk Implement fd, iwjh rjg ls ,d Abstract Form esa Specify dj ldrs gSaA fQj Interface dk iz;ksx djds ge bu fcuk Implemented Interfaces ds lewg dks fdlh Hkh Class ds fy, Implement dj ldrs gSaA okLro esa Interfaces Abstract Classes ds leku gh gksrs gSa] ysfdu buesa ,d Extra Ability ;s gksrh gS fd dksbZ Hkh Class ,d ls T;knk Interfaces dks Implement dj ldrk gSA tcfd Inheritance esa ,d Abstract Class ls gh fdlh ,d Class dks Inherit fd;k tk ldrk gSA interface Keyword dk iz;ksx djds ge Interface dks mlds Implementation ls iwjh rjg ls Abstract dj ldrs gSaA ,d Interface esa ge ;s Specify djrs gSa fd mls Use djus okyh Class D;k&D;k djus esa l{ke gks ldsxkA Interface esa ge ;s Specify ugha djrs gSa] fd Interface mu dkeksa dks dSls Perform djsxk] ftUgsa Interface ls izkIr djsxkA Interface o Class dks Create djus ds Syntax esa dksbZ fo”ks’k vUrj ugha gksrk gSA ysfdu Interface esa dsoy Constant Variables gh Declare fd, tkrs gSa vkSj Interface esa Declare fd, x, Methods dh Body ugha gksrh gSA


Java in Hindi bldk Qk;nk ;s gksrk gS fd ge ftl Class esa fdlh Interface dks izkIr djuk pkgrs gSa] mlh Class esa ml Interface ds lHkh Methods dks Implement dj ysrs gSaA ,d Interface dks ,d ckj Define djus ds ckn ml Interface dks ge ftruh Classes esa pkgsa mruh Classes esa Implement dj ldrs gSaA lkFk gh ge ,d gh Class esa ,d ls T;knk Interfaces dks Implement dj ldrs gSaA ,d Interface dks Implement djus ds fy, gesa Interface esa Declare fd, x, lHkh Abstract Methods dks Class esa iwjh rjg ls Define djuk gksrk gS vkSj gj Class fdlh ,d Interface dks viuh vko”;drkuqlkj Define djus ds fy, iwjh rjg ls Lora= gksrh gSA interface Keyword iznku djds tkok gesa ;s lqfo/kk nsrk gS fd ge “One Interface, Multiple Methods” izdkj ds Polymorphism dks iwjh rjg ls Utilize dj ldsaA D;ksafd Interfaces dks bl rjg ls Design fd;k x;k gS] ftlls gesa tkok esa Run Time esa Dynamic Method Resolution ;kuh Program ds Run Time esa ;s r; djus dh lqfo/kk feyrh gS fd fdl fLFkfr esa dkSulk Method Execute gksuk pkfg,A

lkekU;r;k ,d Class ls nwljh Class esa Methods ds Call gksus ds fy, nksuksa Classes dk tkok Compiler ij Compile Time esa miyC/k gksuk t:jh gksrk gS] rkfd tkok Compiler nksuksa Classes ds Method Signatures dks Compatibility ds fy, Check dj ldsA tkok ds Classing djus ds bl rjhds esa ge ,d Limit esa Bound gks tkrs gSa] D;ksafd fdlh Hkh Sub Class dh Compiling ds fy, mldh lHkh Super Classes dh t:jr gksrh gSA Interfaces dks bl deh dks iwjk djus ds fy, Develop fd;k x;k gSA Interfaces Method ;k Method ds lewg ds Implementations dks Inheritance Hierarchy ls Disconnect dj nsrk gSA D;ksafd Interfaces Classes dh rqyuk esa ,d vyx Hierarchy esa Represent gksrs gSa] blfy, Interfaces Hierarchy ls Unrelated fofHkUu izdkj dh Classes Hierarchy leku izdkj ds Interfaces dks Implement dj ldus esa l{ke gks tkrh gSaA blhfy, ge ,d gh Interface dks vyx&vyx Classes ds fy, Implement dj ldrs gSaA

Declaring Interfaces

ftl izdkj ls ge dksbZ Class Define djrs gSa] mlh rjg ls gesa Interface Hkh Define djuk gksrk gSA ,d Interface dks ge fuEu Syntax ds vuqlkj Create dj ldrs gSa% access interface InterfaceName { Return_Type Method_Name(Parameter_List); //Un-Implemented Methods }

static final Type constantName = Value;

//Constant Data Members

bl Syntax esa access Keyword ;k rks public gksrk gS ;k fQj bls Specify ugha fd;k tkrk gSA tc bls Specify ugha fd;k tkrk gS] rc ;gka Default Access Specifier Friend gksrk gS vkSj ge bl Interface dks dsoy leku Package dh Classes esa gh Use dj ldrs gSaA tcfd public Access Specifier okys Interface dks ge fdlh Hkh Package dh Class ds lkFk Use dj ldrs gSaA interface ,d Keyword gS] tks Interface Create djus dk dke 327 Any Question or Suggestion, Just Discuss Here...

Java in Hindi djrk gSA InterfaceName gekjs Interface dk og uke gksrk gS] ftlls ge bls Access djrs gSaA ;s uke dksbZ Hkh Valid Identifier Name gks ldrk gSA pwafd ,d Interface esa lHkh Methods Abstract gksrs gSa] blfy, Methods ds Declaration esa abstract Keyword dks Use djus dh dksbZ t:jr ugha jgrh gSA fofHkUu Abstract Methods ds Parenthesis ds ckn Semicolon dk iz;ksx djds mUgsa Terminate dj fn;k tkrk gSA bUgsa Implement ugha fd;k tkrk gS] blfy, budh Body ugha gksrh gSA ge fdlh Interface esa fdlh Hkh Method dks Implement ugha dj ldrs gSaA ;fn ge fdlh Interface esa fdlh Method dks Implement ;k Define djrs gSa] rks Compiler Error Generate djrk gS] D;ksafd ,d Interface ds lHkh Methods Abstract gksrs gSa] ftUgsa mlh Class esa Implement fd;k tkrk gS] ftlesa Interface dks Use djuk gksrk gSA lkFk gh ftl fdlh Hkh Class esa gesa ftl fdlh Hkh Interface dks Use djuk gksrk gS] ml Class esa gesa Interface ds lHkh Abstract Methods dks Implement djuk t:jh gksrk gSA ge Interface ds fdlh Hkh Method dks fcuk Implement fd, ugha NksM ldrs gSaA ;fn ge ,slk djrs gSa] rks Compiler Error Generate djrk gSA Interfaces esa ge Variables Hkh Declare dj ldrs gSa] ysfdu fdlh Interface esa ge tks Hkh Variable Declare djrs gSa] os Variables gesa”kk ds fy, Public, Static o Final ;kuh Constants gksrs gSaA blfy, bUgsa Create djrs gh gesa bUgsa Initialize Hkh djuk iMrk gS vkSj pwafd fdlh Interface ds lHkh Variables Constant gksrs gSa] blfy, Interface dks fdlh Class esa Implement djrs le; Hkh ge bu Variables ds eku dks Change ugha dj ldrs

gSaA

;fn fdlh Interface dks Public Declare fd;k tkrk gS] rks mlds lHkh Data Members o Methods By Default Public gks tkrs gSaA Method dk Public gksuk blfy, Hkh t:jh gksrk gS] D;ksafd ftl Class esa Hkh ge Interfaces dks Use djrs gSa] gesa ml Class esa Interface ds lHkh Members dks Implement djus ds fy, Access djuk gh iMrk gSA blfy, ;fn bUgsa Public uk j[kk tk,] rks ge fdlh Interface ds fdlh Method dks fdlh Class esa Implement ugha dj ldsaxs] ftlls Interface dk Meaning gh [kRe gks tk,xkA fdlh Interface dks ge fuEukuqlkj Define dj ldrs gSa% public interface CalculateArea { void area(); }

Extending Interfaces

Classes dh rjg gh ge fdlh Interface dks Hkh Extend djds u;k Sub Interface Create dj ldrs gSaA ge tc Hkh fdlh Interface dks Extend djrs gSa rks Sub Interface esa Super Interface ds lHkh Abstract Methods o Data Members Inherit gks tkrs gSA Interfaces dks Extend djus ds fy, Hkh gesa ogh Syntax Use djuk iMrk gS] ftl Syntax dk iz;ksx ge Class dks Extend djus ds fy, djrs gSaA interface SubInterface extends SuperInterface


Java in Hindi { }

// Constant Data Members // Abstract Method

mnkgj.k ds fy, ;fn ge fdlh Interface esa fuEukuqlkj dsoy Constants dks gh Define djsa% interface ItemInformation{ public static int code = 1000; public static String name = “Freeze”; }

rks bl Interface dks ge fuEukuqlkj Extend dj ldrs gSa% interface ItemInformation { int code = 1000; String name = “Freeze”; }

// Abstract Methods

interface Item extends ItemInformation { // Constant Data Members }

void display();

tc ge bl izdkj ls fdlh Interface dks Inherit djrs gSa] rc Sub Interface Item esa Super Interface ItemInformation ds lHkh Data Members o Methods Inherit gks tkrs gSaA ge ns[k ldrs gSa fd geus ItemInformation Interface esa nksuksa Data Members dks lkekU; Variables dh rjg Declare fd;k gSA ge ,slk dj ldrs gSa] ysfdu ge pkgs public static Keywords dk iz;skx djsa pkgs uk djsa] Interface ds lHkh Data Members By Default Constant gh gksrs gSaA gkykafd ge dbZ Classes ls ,d Sub Class dks ,d ckj esa Extend ugha dj ldrs D;ksafd tkok Multiple Inheritance dks Support ugha djrk gSA ysfdu ge dbZ Interfaces ls ,d u, Sub Interfaces dks ,d ckj esa Extend dj ldrs gSa] bl izfØ;k dks tkok Support djrk gSA ;kuh ge pkgsa rks Interfaces dks fuEukuqlkj Extend dj ldrs gSa% interface DataMemberInfo { int code = 1000; String name = “Freeze”; }

// Abstract Methods


Java in Hindi interface MemberMethodInfo { // Constant Data Members }

void display();

interface MultipleInterface extends DataMemberInfo, MemberMethodInfo { int code = 1000; String name = “Freeze”; }

// Abstract Methods

gkykafd ge ,d Sub Interface esa ,d ls T;knk Interfaces dks Inherit dj ldrs gSa] ysfdu fQj Hkh ge Sub Interface esa fdlh Hkh Super Interface ds fdlh Hkh Method dks Define ugha dj ldrs gSaA lHkh Sub Interfaces vHkh Hkh Interface dh rjg gh Behave djrs gSa] Class dh rjg ughaA lkFk gh tc ge fdlh Interface dks Implement djrs gSa] rks gesa ml Interface ds lHkh Abstract Methods dks Class esa Implement djuk iMrk gSA ysfdu tc ge fdlh Sub Interface dks Class esa Implement djrs gSa] rc gesa ml Sub Interface ds rks lHkh Methods dks Class esa Implement djuk gh gksrk gS] lkFk gh ml Sub Interface dh lHkh Super Interfaces ds Abstract methods dks Hkh gesa Class esa Implement djuk t:jh gksrk gSA tc gesa fdlh Sub Interface esa ,d ls T;knk Interfaces dks Extend djuk gksrk gS] rc lHkh Super Interfaces dks Comma Operator }kjk Separate j[kk tkrk gSA ,d ckr gesa”kk /;ku j[ksa fd ge dHkh Hkh fdlh Interface esa fdlh Class dks Inherit ugha dj ldrs gSaA D;ksafd Class dks Inherit djus ij Class ds Implemented Methods Interface esa Inherit gks tk,axs] tks fd Interface ds fu;e ds f[kykQ gSA

Implementing Interfaces

D;ksafd Interface fdlh Hkh Class ds fy, dsoy ,d Declaration, Prototype ;k Template gksrk gS] blfy, gesa bl Prototype dks mlh Class esa Implement djuk gksrk gS] ftl Class esa gesa mls Use djuk gksrk gSA fdlh Interface dks Implement djuk ml Class dks Derive djus ds leku gh gksrk gSA ysfdu fdlh Class dks Derive djuk ;k ugha djuk gekjh bPNk ij fuHkZj djrk gS tcfd fdlh Interface dks Use djus ds fy, gesa mlds lHkh Methods dks viuh ml Class esa Implement djuk gh gksrk gS] ftlesa ge Interface dks Use djuk pkgrs gSaA fdlh Interface dks fdlh Class esa Implement djus ds fy, gesa implements Keyword dk iz;ksx djuk gksrk gSA fdlh Interface ds Method dks fdlh Class esa Implement djus dk Syntax fuEukuqlkj gksrk gS%


Java in Hindi class ClassName [extends SuperClass] implements InterfaceName1 [,InterfaceName2, ..., InterfaceNameN] { // Class Members // Methods }

;gka ClassName Create gksus okyh ubZ Class gSA ;fn Class fdlh nwljh Super Class ls Inherit gks jgk gks] rks gesa Class dks Extend djus okys Syntax ds ckn Implement Syntax dks fy[kuk gksrk gSA InterfaceName og Interface gS] ftls ClassName uke dh Class esa Implement fd;k tk jgk gSA ge ,d ckj esa dsoy ,d gh Super Class dks Inherit dj ldrs gSa] ysfdu ge ,d ckj esa ,d ls T;knk Interfaces dks Extend dj ldrs gSaA tkok ds Interfaces dh blh lqfo/kk ds dkj.k ge tkok esa Multiple Inheritance Concept ds Alternate ds :i esa Interfaces dks Use dj ldrs gSaA vxys Program esa geus lcls igys Area uke dk ,d Interface Create fd;k gSA bl Interface dks fdlh Hkh Shape dk Area Calculate djus ds fy, Implement fd;k tk ldrk gSA blh Program esa vkxs geus Rectangle o Circle uke dh nks Classes Create dh gSa vkSj bu Classes ds Objects dk Area Calculate djus ds fy, Interface dks bu nksuksa Classes esa Implement fd;k x;k gSA bl Program esa geus Rectangle o Circle nksuksa Classes ds new Operator dk iz;ksx djds Object Create fd, gSa] tcfd blh Program esa geus Interface Area Type dk ,d Reference Create fd;k gSA ge Interface Type dk Object Create dj ldrs gSa] D;ksafd ;s Hkh ,d rjg dh Class gh gS] ysfdu Pure Abstract Class gSA fQj bl Interface Area Type ds Reference esa geus Rectangle Class ds Object dk Reference Area Type ds Reference esa Assign djds computArea() uke ds Method dks Call fd;k gSA ;s Method Interface Class esa Declare fd;k x;k Abstract Method gS] blfy, bls Rectangle Class esa Implement fd;k x;k gSA tc Interface Area Class ds Object esa Rectangle Class dk Reference gksrk gS] rc tkok Rectangle Class ds computArea() Method dks Execute djds Rectangle Object dk Area Calculate dj nsrk gSA blh rjg ls Interface ds computArea() Method dks Circle Class esa Hkh Implement fd;k x;k gS] blfy, tc ge Circle Class ds Object dk Reference Area Interface Class ds Object dks nsrs gSa vkSj mlds Reference esa computArea() Method dks Call djrs gSa] rks D;ksafd Interface Area ds Object esa Circle Class dk Reference gksrk gS] blfy, tkok Circle Class ds computArea() Method dks Call djds Area Class ds Object dk Area Calculate dj ysrk gSA Program // File Name: InterfaceImplementation.java interface Area { final static float PI = 3.14f; float computeArea(float x, float y);


Java in Hindi } // Interface Implementation in Rectangle Class class Rectangle implements Area { public float computeArea(float x, float y){ return ( x * y ); } } // Interface Implementation in Circle Class class Circle implements Area{ public float computeArea(float x, float y){ return ( PI * x * y ); } } class InterfaceImplementation{ public static void main(String args[]){ Rectangle myRectangle = new Rectangle(); Circle myCircle = new Circle(); Area shape; shape = myRectangle; System.out.println("Area of Rectangle = "+shape.computeArea(10, 20));

}

shape = myCircle; System.out.println("Area of Rectangle = "+shape.computeArea(10, 20));

Output Area of Rectangle = 200.0 Area of Rectangle = 628.0

ge vyx&vyx izdkj dh fofHkUu Classes esa fdlh Interface dks Implement dj ldrs gSaA fQj Hkh Method dks Implement djus ds fy, gesa Class ds Object dks Interface }kjk Refer djuk t:jh gksrk gSA ge fdlh Class ds Method ls fdlh Implemented Method dks Execute ugha dj ldrs gSaA ,d ckr gesa”kk /;ku j[ksa fd ;fn ge fdlh Class esa fdlh Interface dks Implement djrs gSa] ysfdu ml Interface dh lHkh Methods dks Class esa Implement ugha djrs gSa] rks ftl Class esa ge Interface ds dqN Methods dks Implement djrs gSa] og Class Hkh Abstract Class cu tkrh gS vkSj ge ml Class ds Hkh Object Create ugha dj ldrs gSaA tc ge fdlh Interface dks Implement djrs gSa] rc Interface dks Implement dh tk jgh Class esa Abstract Method dks Public Form esa Implement djuk t:jh gksrk gS] pkgs geus Interface esa Method dks Public Declare fd;k gks pkgs uk fd;k gksA


Java in Hindi fiNys mnkgj.k esa geus Rectangle o Circle nksuksa gh Classes esa computArea() Method dks Public Form esa Implement fd;k gS] tcfd Interface Area esa computArea() Abstract Method ds lkFk fdlh Access Specifier dk iz;ksx ugha fd;k gSA ;fn ge ,slk ugha djrs gSa] rks tkok Compiler gesa Error nsrk gSA lkFk gh Interface ds Abstract Method dk Signature o mls ftl Class esa Implement fd;k tk jgk gS] ml Class esa Implement fd, tk jgs Method] nksuksa dk Signature leku gksuk Hkh t:jh gksrk gSA os Classes ftuesa fdlh Interface dks Implement fd;k tk jgk gksrk gS] muesa vU; Non-Interface Methods Hkh Define fd, tk ldrs gSaA ge ,sls Interface Hkh Create dj ldrs gSa] ftlesa dksbZ Hkh Abstract Method uk gks] cfYd mlesa dsoy Constant Variables gh gksa] ftUgsa fofHkUu izdkj dh Classes esa leku :i ls Use fd;k tkuk gksA ;kuh ;fn dqN ,sls Constant eku gksa ftudh t:jr fofHkUu izdkj dh dbZ Classes esa iMrh gS] rks ge bl izdkj ds Constant Members dks Hkh Interface es Specify dj ldrs gSA fQj ftl fdlh Hkh Class esa gesa mu Constant Members dh t:jr gksrh gS] mu Classes esa ml Interface dks Implement dj ysrs gSaA ;s Interfaces okLro esa “C” dh ,d Header File ds leku gh dke djrs gSa] ftlesa fofHkUu izdkj ds #define izdkj ds Constants ;k const Keyword ds lkFk Declare fd, x, Constants dks Store djds j[kk tkrk gSA tc Hkh gesa fdlh Program esa bu Constant ekuksa ds lewg esa ls fdlh eku dh t:jr gksrh gS] ge ml Header File dks vius Program esa Include djds mu Constants dks Use dj ysrs gSa] mlh rjg ls bl izdkj ds Interfaces dks ge ml Class esa Implement dj ysrs gSa] ftuesa bu Interfaces esa Define fd, x, Constants dh t:jr gksrh gSA pwafd ,sls Interfaces esa dksbZ Method ugha gksrk gS] blfy, gesa Interface ds fdlh Hkh Method dks Implement djus dh t:jr ugha gksrh gSA ge Interface ds lHkh Constants dks viuh Class esa Directly Access djds Use dj ysrs gSaA bu Interfaces ds Constants dks ge Class ds fdlh Hkh Method esa Use dj ldrs gSaA bl izfØ;k dks ge fuEukuqlkj Code Segment ls le> ldrs gSa% interface OnlyConstants { int xCoordinate = 200; int yCoordinate = 250; } class ImplementOnlyConstantsInterface implements OnlyConstants { int newCoordinate = xCoordinate; void getNewCoordinate(int center) { ... ... if(yCoordinate < newCoordinate) { ...


Java in Hindi

}

}

}

...

tc ge bl izdkj dk Interface Create djrs gSa] rc Interface ds Data Members ,sls Constants gksrs gSa] tks fofHkUu Classes }kjk vkil esa Share gksrs gSaA bl izdkj ds Interface dks fdlh Class esa Implement djus dk eryc gksrk gS fd ge Interface ds lHkh Constants dks ,d izdkj ls viuh ml Class ds fy, Available dj jgs gSa] rkfd gekjh Class Interface ds mu lHkh Constants dks Use dj ldsA okLro esa bl izdkj ds Interfaces Classes esa fdlh Hkh rjg ls Implement ugha gksrs gSa] cfYd muesa miyC/k ;k Declared lHkh Constants gekjh Class esa miyC/k gks tkrs gSa] ftUgsa Class viuh t:jr ds vuqlkj Use dj ldrk gSA tc ge ,d ,slh Class Create djrs gSa] ftlesa fdlh Interface dks Implement rks fd;k tkrk gS] ysfdu Interface ds lHkh Methods dks Implement ugha fd;k tkrk gS] rc ,slh Class dks gesa Abstract Class Declare djuk t:jh gksrk gSA bl izdkj ds Implementation dks Partial Implementation dgrs gSaA D;ksafd bl fLFkfr esa gekjs lkeus tks Class gksrh gS] og Hkh ,d Abstract Class gksrh gS] D;ksafd Extend gksus ds ckn lHkh Interfaces Class esa vk tkrs gSaA vc ;fn ge Class esa Interface ls Extend gksus okyh lHkh Methods dks Implement ugha djrs gSa] rks Class esa Abstract Method jgrs gS vkSj ftl Class esa Abstract Method jgrs gSa] ml Class dks Abstract Class Declare djuk t:jh gksrk gSA


Java in Hindi

Java Exceptions For

Error Handling


Java in Hindi Java Exception – Error Handling

dksbZ Hkh Program dHkh Hkh First Attempt esa Successfully Run gks tk,] ,slk dHkh dHkkj gh gksrk gSA fdlh Program dks Develop o Type djrs le; mlesa Mistakes jg tkuk LokHkkfod gS vkSj Program esa tc dksbZ Mistake jg tkrh gS] rc Program esa Error Generate gksrk gS vkSj Errors gesa”kk Unexpected Results iznku djrk gSA fdlh Program esa dh xbZ os xyfr;ka tks Program esa Unexpected Results Generate djrs gSa] Errors dgykrs gSaA lkekU;r;k fdlh Hkh Program esa Semantic o Logical nks rjg dh xyfr;ka gksrh gSaA tc Program dks Type djrs le; ge fdlh izdkj dh Typing Mistake djrs gSa] rks bl izdkj dh xyrh gksus ij lkekU;r;k dksbZ Program Compile ugha gksrk gSA bl izdkj dh xyfr;ksa ls tks Error Generate gksrk gS] mls Compile Time Error Hkh dgrs gSaA tcfd dqN xyfr;ka ,slh gksrh gSa] tks Logical gksrh gSaA bl izdkj dh xyfr;ksa ls tks Error Generate gksrk gS] ml Error dks Run Time Error dgrs gSaA tc fdlh Program esa Error gksrk gS] rc ;k rks Program lgh Result iznku ugha djrk gS] ;k fQj Program lkekU; :i ls Run gksrs&gksrs vpkud fdlh fo”ks’k ifjfLFkfr esa Crash gksdj Terminate gks tkrk gSA

Compile Time Errors

os lHkh Errors ftUgsa Program dks Compiler djrs le; Compiler }kjk Identify dj fy;k tkrk gS] Compile Time Errors dgykrs gSaA tc Hkh fdlh Program File esa dksbZ Error gksrh gS] tkok Compiler ml Source File dh .class File Create ugha djrk gSA blfy, tc Hkh fdlh Program dks Compile djrs le; tkok gesa dksbZ Error Display djrk gS] gesa mu Errors dks Debug djuk t:jh gksrk gS] rkfd Program Bhd rjg ls Compile o Run gks ldsA Compile Time Errors lkekU;r;k ;k rks Typing Mistake ds dkj.k Generate gksrs gSa ;k fQj Programming Code Statements dks Misplaced djus ij Generate gksrs gSaA mnkgj.k ds fy, fuEu Code Segment nsf[k,% class ErrorDemo { public static void main(String arg[]) { System.out.printnl(“Hello Java !”); } }

tc gekjs Source Program esa dksbZ Typing Mistake gks tkrh gS] rc tkok Compiler gesa ;s Hkh crkrk gS fd Program dh fdl Line esa Error gSA mnkgj.k ds fy, tc ge fiNys Program dks Compile djrs gSa] rc tkok Compiler gesa fuEukuqlkj Error Message nsrk gS] ftlesa igyh Line esa gh og gesa crk jgk gS fd Program dh 6th Line esa Error gS ftlesa tkok dks ,d ,slk Symbol ;k Statement fey jgk gS] ftls tkok ugha igpkurk gSA geus bl Program esa println() Method ds LFkku ij printnl() Method iz;ksx fd;k gSA


Java in Hindi pwafd tkok esa bl uke dk dksbZ Method ugha gS] blfy, tkok ,d Error Message Display dj nsrk gSA lkFk gh tkok ml LFkku ij ,d Caret Symbol ( ^ ) }kjk gesa ;s Hkh Indicate djrk gS fd Error Statement ds fdl LFkku ij gSA D:\Java\ErrorDemo.java:6: cannot resolve symbol symbol : method printnl (java.lang.String) location: class java.io.PrintStream System.out.printnl("Hello Java !"); ^ 1 error

tkok }kjk iznku fd, tk jgs bl Error Output ds vk/kkj ij ge Program esa Appropriate Line ij tkdj ml Error dks lgh dj ldrs gSaA Program esa dbZ ckj dksbZ ,d ,slh Error gksrh gS] tks dbZ vU; nwljh Errors ds Source dk dke djrh gSA mnkgj.k ds fy, fdlh Program esa fdlh Variable dks Declare fd, fcuk gh mls Program esa Use dj fy;k tk,] rks Program gesa “undefined variable” izdkj ds cgqr lkjs Errors Display dj nsrk gS] tcfd ge tSls gh ml Variable dks Declare djrs gSa] Program dh lkjh Errors Bhd gks tkrh gSaA lkekU;r;k fdlh Hkh Program dks Debug djus dk lcls Best rjhdk ;gh gS fd Program dh lHkh Typing lEcaf/kr Errors dks Top ls Bottom dh rjQ pyrs gq, lgh djsaA ,slk djus ij ml izdkj ds Errors cgqr tYnh idM esa vk tkrs gSa] tks dbZ vU; Errors dks Generate djus dk dke djrs gSaA

Run Time Errors

dbZ ckj ,d Program vPNh rjg ls Compile gksrk gS vkSj mldh .class File Hkh curh gSA Program lkekU; rjhds ls Run Hkh gksrk gS] ysfdu fdlh fo”ks’k ifjfLFkfr ds vkrs gh Program Terminate gks tkrk gS] ;k xyr Result iznku djus yxrk gSA bl izdkj dh Errors okLro esa Logical Errors gksrh gSa vkSj bUgsa Debug djuk lcls eqf”dy dke gksrk gSA pwafd ;s Errors Program ds Run Time esa dqN fo”ks’k ifjfLFkfr;ksa esa Generate gksrs gSa] blfy, bl izdkj ds Errors dks Run Time Errors dgk tkrk gSA tc bl izdkj dh Errors Program esa Generate gksrh gSa] rc tkok Interpreter ,d Error Message Generate djrk gS vkSj Program dks Terminate dj nsrk gSA bl izfØ;k dks ge fuEu Program }kjk le> ldrs gSa] ftlesa ,d fLFkfr ds ckn ,d la[;k esa 0 dk Hkkx fn;k tkus yxrk gS] tcfd fdlh Hkh la[;k esa 0 dk Hkkx ugha fn;k tk ldrk gSA bl fLFkfr esa tc rd ,d lkekU; la[;k dk Hkkx fn;k tkrk gS] Program lgh rjhds ls dke djrk gS] tcfd tSls gh la[;k esa 0 dk Hkkx fn;k tkrk gS] Program Error Message nsrk gS vkSj Terminate gks tkrk gSA

Program class ErrorDemo2 { public static void main(String Arg[]) {


Java in Hindi int x = 15, y = 5, z = 5, result=0; result = x / (y+z); System.out.println("Value of result = " + result); result = x / (y-z+1); System.out.println("Value of result = " + result);

}

}

result = x / (y-z); // Error: Division by zero System.out.println("Value of result = " + result);

Output Value of result = 1 Value of result = 15 Exception in thread "main" java.lang.ArithmeticException: / by zero at ErrorDemo2.main(ErrorDemo2.java:14)

;s Program Syntactically iwjh rjg ls lgh gS] fQj Hkh Program Run gksrs le; tc ml LFkku ij vkrk gS] ftls geus Program esa Bold fd;k gS] rc tkok ,d Error Message nsrk gS] vkSj Terminate gks tkrk gS] D;ksafd bl Statement esa x esa y-z ;kuh 0 dk Hkkx fn;k x;k gSA tkok tc bl “Division By Zero” okys Statement dks Execute djus dh dksf”k”k djrk gS] rc ,d Error Generate gksrk gS] ftlds Reaction esa Program ,d Error Message nsrk gS vkSj Terminate gks tkrk gSA

Exceptions

tkok Exception ,d Object gksrk gS] tks fdlh Run Time Error dks Represent djrk gSA ;s ,d rjg dk Exception Event Object ;k Abnormal Event Object gS] tks rc Generate gksrk gS] tc Program vius Normal Flow ls vpkud Disturb gks tkrk gSA tkok Program esa tc Hkh dksbZ Run Time Error Generate gksus dh lEHkkouk gksrh gS] rks ml Run Time Error dks Exception dgk tkrk gSA tkok Interpreter Program dks Normal Flow esa Run djrk jgrk gSA ysfdu ;fn fdlh dkj.ko”k tkok Interpreter dks dksbZ Statement Execute djus esa ijs”kkuh gksrh gS] rks tkok Interpreter ml Statement ls lEcaf/kr ijs”kkuh dks ,d Object Create djds Represent djrk gSA bl Object dks Exception Object dgk tkrk gSA tc tkok Interpreter dksbZ Exception Object Create djrk gS] rks lkekU; Hkk’kk esa bls Exception Object Throw djuk dgk tkrk gSA ;kuh tkok dks tc Hkh dHkh fdlh Statement dks Run djus esa ijs”kkuh gksrh gS] tkok ,d Exception Object Create djds Throw djrk gSA ;fn tkok dksbZ Exception Object Throw djrk gS vkSj ml Exception Object dks gekjs Program dk dksbZ Hkh Error Handling Method Catch djds lgh rjhds ls Handle ugha djrk gS] rks og Error Object tkok ds Default Exception Handler ij pyk tkrk gS vkSj tkok dk Default Exception Handler ml Exception dks Handle djus ds Response esa ,d Error Message Display djds Program dks Terminate dj nsrk gSA tc bl izdkj dh 338 Any Question or Suggestion, Just Discuss Here...

Java in Hindi fdlh Error ls Program Terminate gksrk gS] rks bl izfØ;k dks Program dk Crash gksuk dgrs gSaA lkekU;r;k ge ;s dHkh ugha pkgrs gSa fd gekjk Program dHkh Hkh fdlh Hkh fLFkfr esa fcuk Proper Output fn, Terminate gks tk, ;k Crash gks tk,A ge gesa”kk ;gh pkgrs gSa fd gekjk Program gesa”kk lgh rjg ls Run gks vkSj gesa”kk lgh Result gh iznku djsA bl fLFkfr esa ;s t:jh gks tkrk gS fd ;fn dHkh fdlh Program esa fdlh izdkj dh dksbZ Run Time Error Generate gks Hkh tkrh gS] rks Hkh gekjk Program Continue jgs vkSj vius Program esa ;s fLFkfr ge rHkh izkIr dj ldrs gSa] tc ge Program dh fofHkUu Run Time Errors dks Handle djus ds fy, igys ls gh dksbZ uk dksbZ O;oLFkk dj nsaA tkok esa Exceptions dks Handle djus ds fy, ,d lqO;ofLFkr Object Oriented Approach dks Develop fd;k x;k gSA tkok esa tc Hkh dksbZ Exception Generate gksrk gS] tkok ml Exception dks Represent djrk gqvk ,d Object Create djds Throw djrk gSA bl Object esa Generate gksus okyh Error ls lEcaf/kr tkudkfj;ka gksrh gSaA tkok }kjk Throw fd, tkus okys bl Exception Object dks ,d Exception Handler Method esa Catch dj fy;k tkrk gSA pwafd bl Object esa Exception ls lEcaf/kr tkudkfj;ka Hkh gksrh gSa] blfy, bl Object dks Bhd rjhds ls Manage djds Program Control dks fQj ls mlh Statement ls vxys Statement ij Hkst fn;k tkrk gS] ftl Statement ij Exception Generate gqvk FkkA pwafd Exception Handling Method Program Control dks fQj ls ml Statement ls vkxs ds lHkh Statement dks lkekU; rjhds ls Execute djus ds fy, Hkst nsrk gS] tgka Exception Generate gqvk Fkk] blfy, Exception Generate gksus ij Hkh Program Crash gks dj Terminate ugha gksrk gSA Exception dks bl izdkj ls Handle djus dh Process dks “Exception Handling Process” dgk tkrk gSA Exception Handling Process ,d ,slk Mechanism gS] tks gesa fdlh Error dks Detect djus dh lqfo/kk nsrk gS] rkfd ge ml Exception dks Handle dj ldsaA bl Mechanism esa vyx ls ,d Error Exception Handling Code Block fy[kk tkrk gSA ;s Code Block fuEu dke djrk gS% Problem Find djrk gSA (Hit the Exception) dksbZ Exception Generate gksus ij Inform djrk gSA (Throw the Exception) Error dh Information dks Exception Object ls Receive djrk gSA (Catch the Exception) mfpr Action Perform djrk gSA (Handle the Exception)

lkekU;r;k Error Handling Code ds nks Hkkx gksrs gSaA igyk Hkkx Error dks Detect djrk gS vkSj Exception Object Throw djrk gS rFkk nwljk Hkkx Exception dks Handle djus ds fy, Appropriate Actions Perform djrk gSA ge tc Hkh dksbZ Program fy[krs gSa] gesa gesa”kk ;s r; djus dh dksf”k”k djuh gksrh gS fd fdl fLFkfr esa fdl izdkj dk Exception Generate gks ldrk gS vkSj ml Exception dks fdl izdkj ls Handle fd;k tkuk pkfg,A tkok esa Exception Handling dks eq[;r;k ikap Keywords try, catch, throw, throws o finally }kjk Manage fd;k tkrk gSA ge ftl Program Statement dks Exception ds fy, Monitor djuk pkgrs gSa ;k tks Code Statements Exceptions Generate dj ldrs gSa] mu 339 Any Question or Suggestion, Just Discuss Here...

Java in Hindi Statements dks ge try Block esa fy[krs gSaA try Block esa fy[ks x, Code Statements esa ;fn dksbZ Exception Generate gksrk gS] rks try Block ml Exception Object dks Throw djrk gSA try Block }kjk Throw fd, x, Exception Object dks Catch djus ds fy, try Block ls Just uhps catch Block fy[kk tkrk gSA catch Block try }kjk Throw fd, x, Exception Object dks Catch djds Appropriate Actions Perform djrk gS vkSj Program Control dks fQj ls try Block esa ml Statement ls vxys Statement ij Hkst nsrk gS] tgka Exception Generate gqvk FkkA System Generated Exceptions dks tkok Lo;a gh Automatically Java Run Time Environment ij Throw dj nsrk gSA ge Manually Hkh fdlh Exception dks Throw dj ldrs gSaA fdlh Exception dks Manually Throw djus ds fy, gesa tkok ds throw Keyword dk iz;ksx djuk iMrk gSA ;fn dksbZ Method ,slk Exception Generate djus esa l{ke gks] ftls og Method Loa; Handle ugha dj ldrk gS] rks bl izdkj ds Exception dks og Method Handle djrk gS] tks Method Exception Generate djus okys bl Method dks Call djrk gSA

bl izdkj dh fLFkfr ftlesa Method Exception Throw dj ldrk gS] Exception dks Throw djokus ds fy, gesa throws Keyword ds Statement dk iz;ksx djuk iMrk gSA throws Statement dk iz;ksx mu Exceptions dh List Create djus ds fy, fd;k tkrk gS] ftUgsa Method Throw djrk gSA tc Hkh dHkh fdlh Statement ij dksbZ Exception Generate gksrk gS] Program Control ml Statement ls vkxs ds Statements dks Ignore dj nsrk gSA ysfdu dqN fLFkfr;ka ,slh gksrh gSa] ftlesa fdlh Statement ij Exception Generate gksus ds ckotwn Hkh Program ds dqN vU; Statement dk Execution djus ds ckn gh ml Exception dks Handle djuk gksrk gSA bl izdkj ds ftrus Hkh Statements gksrs gSa] ftUgsa fdlh Hkh fLFkfr esa Exception Handling ls igys gh Execute djuk t:jh gksrk gS] mUgsa finally Block esa fy[kk tkrk gSA fdlh Exception dks Handle djus dk General Block fuEukuqlkj gksrk gS% try {

// Block of codes to be monitored for errors } catch(ExceptionType1 excepObj) { // Exception Handler for ExceptionType1 } catch(ExceptionType2 excepObj) { // Exception Handler for ExceptionType2 } ... ... ... catch(ExceptionTypeN excepObj) {


Java in Hindi // Exception Handler for ExceptionTypeN } finally(ExceptionType2 excepObj) { // Block of codes which must be executed before try block ends }

;gka ExceptionType og Class gS] ftlds Exception Object Throw gq, gSaA blls vkxs ds v/;k; esa ;gh crk;k x;k gS fd ge Exception Handling dh bl rduhd dks fdl izdkj ls Use dj ldrs gSaA

Exception Types tkok esa ftrus Hkh izdkj dh Exceptions dks Represent djus okyh ExceptionType Classes gSa] os lHkh Built-In Throwable Class dh Sub Classes gSaA vr% Throwable Class Exception Hierarchy Classes dh Top dh Super Class gSA Throwable Class dh nks Sub Classes gSa] tks fdlh Exception dks nks Distinct Branch esa foHkkftr dj nsrk gSA igyh Sub Class dk uke Exception gSA bl Class dk iz;ksx Exceptional Condition ;kuh Exception dks Represent djus okys Object dks Create djds Throw djus ds fy, fd;k tkrk gS] ftls gekjk Program catch Block esa Catch djrk gSA lkFk gh ;fn ge gekjs Lo;a ds Exceptions dh Custom Class cukuk pkgrs gSa] rks og ubZ Class blh Sub Class dh Sub Class gksrh gSA Exception Class dh ,d vkSj cgqr gh egRoiw.kZ Class gS] ftls RuntimeException Class dgk tkrk gSA Division By Zero, Invalid Array Indexing blh izdkj ds Exceptions ds mnkgj.k gSaA fofHkUu izdkj ds Runtime Exceptions gekjs }kjk Create fd, tk jgs fdlh Hkh Program dh Class ds fy, Automatically Define gks tkrs gSaA Throwable Class dh nwljh Sub Class dk uke Error Class gSA ;s mu Exceptions dks Define djrs gSa] ftUgsa Program ds Normal Flow esa Catch fd, tkus dh lEHkkouk ugha gksrh gSA Error izdkj ds Exceptions dks Java Runtime Environment System Loa; Handle djrk gSA Stack Overflow gksuk blh izdkj dh ,d Error gS] ftls tkok Loa; Handle djrk gSA blds fy, ge gekjs Program esa fdlh izdkj dh dksbZ O;oLFkk ugha djrs gSaA

try and catch Block – The Exception Handling Process gkykafd tkok dk Default Exception Handler Debugging ds fy, dkQh mi;ksxh gS] fQj Hkh fdlh Hkh Program esa Generate gksus okys fdlh Hkh Exception dks vDlj ge Lo;a gh Handle djrs gSaA ,slk djus ls nks Qk;ns gksrs gSaA igyk ;s fd gesa Error dks Fix djus dh lqfo/kk fey tkrh gS vkSj nwljk ;s fd blls Program Automatically Terminate ugha gksrkA tc gesa fdlh Code Statement dks Exception ds fy, Monitor djuk gksrk gS] rc ge ml Statement Block dks try Block esa fy[krs gSa vkSj bl Block ds Just vkxs catch Block fy[krs gSa] ftlesa ge ml Exception ds Type dks Specify djrs gSa] ftls ge catch Block esa Catch djuk pkgrs gSaA bl izfØ;k dks le>us ds fy, fuEu Program nsf[k,] ftlesa Division By Zero Exception dks Handle fd;k x;k gS%


Java in Hindi Program class ExceptionDivisionByZero { public static void main(String args[]) { int number, divider; try {

divider = 0; number = 10 / divider;

System.out.println(“This will not be printed.”); } catch(ArithmeticException ae) { System.out.println(“Division by zero.”); } System.out.println(“After catch statement”); }

} Output Division by zero. After catch statement

ge ns[k ldrs gSa fd try Block esa fy[kk x;k println() Statement Execute ugha gks ik;k gSA ,slk blfy, gksrk gS] D;ksafd tSls gh Exception Generate gksrk gS] try Block ,d Exception Object Throw djrk gS] ftls catch Block Catch djrk gSA ;kuh Program Control Exception Object ds lkFk gh try Block ls ckgj fudy dj catch Block esa vk tkrk gS] blhfy, try Block dk println() Statement Execute ugha gks ikrk gSA try o catch Block ,d Unit ds :i esa dke djrs gSaA catch Block rHkh Execute gksrk gS] tc try Block esa dksbZ Exception Generate gksrk gSA Throwable Class esa Object Class }kjk Define fd, x, toString() Method dks Override fd;k x;k gS] rkfd Throwable Class Exception dh Description dks String ds :i esa Display fd;k tk ldsA Exception dh Description dks ,d Argument ds :i esa println() Method esa Pass djds Display djok ldrs gSaA ;kuh try Block }kjk Throw fd, tkus okys fdlh Exception Object dks catch Block esa ge fuEukuqlkj fdlh println() Statement }kjk Hkh Display djok ldrs gSa% Program class ExceptionDivisionByZero{ public static void main(String args[]){ int number, divider; try{

divider = 0; number = 10 / divider;


Java in Hindi System.out.println("This will not be printed.");

}

}

} catch(ArithmeticException ae){ System.out.println("Exception : " + ae ); } System.out.println("After catch statement");

Output Exception : java.lang.ArithmeticException: / by zero After catch statement

gkykafd bl izdkj ds Description dk User ds fy, dksbZ egRo ugha gksrk gSA ysfdu fQj Hkh tc ge fdlh Program dks Debug dj jgs gksrs gSa] ml le; bl izdkj ds Description dk ,d Programmer ds fy, dkQh mi;ksx gksrk gSA

Multiple catch Blocks dbZ ckj ,slh ifjfLFkfr;ka gksrh gSa fd ,d gh try Block ls ,d ls T;knk izdkj ds Exceptions Generate gks ldrs gSaA bl izdkj dh fLFkfr;ksa dks Solve djus ds fy, ge ,d ls T;knk catch Block dks Use dj ldrs gSa] tgka gj catch Block ,d vyx izdkj ds Exception dks Handle djus dk dke djrk gSA tc try Block dksbZ Exception Object Throw djrk gS] rc fofHkUu catch Blocks esa Throw fd, x, Object ds Type dks Check fd;k tkrk gSA ftl catch Block dk Type Throw fd, x, Object ds leku gksrk gS] og catch Block Execute gks tkrk gS vkSj vU; catch Blocks Bypass gks tkrs gSaA bl izfØ;k dks ge fuEukuqlkj mnkgj.k }kjk le> ldrs gSa% Program class MultipleCatchBlock { public static void main(String args[]) { try { int number = args.length; System.out.println("Command Line Arguments = " + number); int x = 122/number; int y[] = {1}; y[10] = 99; } catch(ArithmeticException ae) {


Java in Hindi

}

}

System.out.println("Arithmetical Exception : Divide by zero"); } catch(ArrayIndexOutOfBoundsException ae) { System.out.println("Array Bound Exception :" + ae); } System.out.println("After try / catch Blocks.");

Output: For ArithmeticException Catch Block Command Line Arguments = 0 Arithmetical Exception : Divide by zero After try / catch Blocks. Output: For ArrayIndexOutOfBoundsException Catch Block Command Line Arguments = 1 Array Bound Exception :java.lang.ArrayIndexOutOfBoundsException After try / catch Blocks.

bl Program esa ;fn dksbZ Command Line Parameter iznku ugha fd;k tk,xk] rks blesa Division By Zero dh Error Generate gksxhA pwafd ;s ,d Arithmetical Type Exception gS] blfy, bl Exception dks Program dk igyk catch Block Catch djsxkA tcfd ;fn User Command Prompt ij ,d Hkh Argument Pass djrk gS] rks Division By Zero dh Exception Generate ugha gksrh gS] cfYd ArrayIndexOutOfBoundsException Generate gksrh gSA pwafd Array dh Size rks 1 gS vkSj ge Index Number 10 ij eku 99 dks Store djuk pkgrs gSa] tks fd lEHko ugha gSA blfy, Array ds Bound ls lEcaf/kr Exception Generate gksrk gS] tks Program ds nwljs catch Block }kjk Handle gksrk gSA tc ge Multiple Catch Block Statement Use djrs gSa] rc gesa bl ckr dk /;ku j[kuk gksrk gS fd Exception Sub Class ds Exception dks Handle djus dk catch Block fdlh Hkh vU; Super Class Block ls igys Define gksuk t:jh gksrk gSA gesa ,slk blfy, djuk t:jh gksrk gS D;ksafd ,d ,slk catch Block tks ,d Super Class dks Use djrk gS] og Super Class ds Exceptions dks rks Catch djsxk] lkFk gh og Sub Class ds Hkh lHkh Exceptions dks Catch dj ysxk] D;ksafd gj Sub Class “Kind Of” Super Class gksrk gS vkSj dksbZ Super Class Reference Object fdlh Hkh Sub Class ds Object dks Refer dj ldrk gSA blfy, ;fn ge fdlh Super Class ds catch Block dks mlds fdlh Hkh Sub Class ds catch Block ls igys Define dj nsaxs] rks Throw fd;k x;k Sub Class Object dHkh Hkh mlds Sub Class catch Block rd ugha igqap ik,xkA blfy, tc Hkh gesa Multiple catch Block dks Use djuk gksrk gS] gesa gesa”kk lcls igys Sub Classes ds catch Block dks Define djuk gksrk gS vkSj lcls vUr esa mudh Super Class ds catch Block dks Define djuk gksrk gSA bl Process dks fuEukuqlkj ,d Program }kjk le>k;k x;k gS% Program class MultipleCatchBlockHiearchy{ public static void main(String args[])

{


Java in Hindi try{

int x = 0; int y = 12/x;

} catch(Exception ae){ System.out.println("Generic Exception catch block."); }

}

}

catch(ArithmeticException ae){ System.out.println("This statement never reached"); }

Output D:\Java\MultipleCatchBlockHiearchy.java:17: exception java.lang.ArithmeticException has already been caught catch(ArithmeticException ae) ^ 1 error

;fn ge bl Program dks Compile djus dh dksf”k”k djrs gSa] rks gesa ,d Error Message izkIr gksrk gS] tks ;s crkrk gS fd ftl Exception dks catch djus ds fy, bl catch Block dks fy[kk x;k gS] og Exception Object bl catch Block rd vkus ls igys gh Catch gks jgk gSA D;ksafd ArithmeticException Class Exception Class dh Sub Class gS vkSj geus Exception Class ls lEcaf/kr lHkh Exceptions dks Handle djus ds fy, igys gh catch Block Define dj fn;k gSA pwafd ge tkurs gSa fd lHkh izdkj ds Exception Objects “Kind Of” Exceptions gh gSaA ;kuh ftrus Hkh Exception Object Generate gksrs gSa] mUgsa Super Class Exception }kjk Catch fd;k tk ldrk gS] blfy, ArithmeticException tks fd Exception Class dh Sub Class gS] bl Exception dks Handle djus okys catch Block rd tkok dHkh Hkh ugha igqap ik,xkA bl Exception dks handle djus ds fy, t:jh gS fd ge igys fofHkUu Sub Classes ds Exceptions dks Reverse Hierarchy ds :i esa Define djsa vkSj lcls vUr esa Super Class Exception ds catch Block dks Define djsaA ;kuh gesa blh Program dks fuEukuqlkj Define

djuk gksxk%

Program class MultipleCatchBlockHiearchy { public static void main(String args[]) { try {

int x = 0; int y = 12/x;


Java in Hindi } catch(ArithmeticException ae) { System.out.println("Now this statement is reachable."); }

}

}

catch(Exception ae) { System.out.println("Generic Exception catch block."); }

Output Now this statement is reachable.

dbZ ckj ,slh fLFkfr;ka gksrh gSa] fd catch Block dks Define fd, fcuk ge Program dks Normal Flow esa Run ugha dj ldrs gSa vkSj catch Block esa gesa dqN Extra Ordinary dke djuk ugha gksrk gSA bl fLFkfr esa catch Block dks Define rks fd;k tkrk gS] ysfdu ml Block esa dksbZ Statement ugha fy[kk tkrk] cfYd Definition Block dks Empty NksM fn;k tkrk gSA tc gesa fdlh Exception dks Handle ugha djuk gksrk gS] rc ge fuEukuqlkj fdlh Exception dks Skip dj ldrs gSa% Program class NothingToDoInCatch { public static void main(String args[]) { try { }

}

}

int x = 0; int y = 12/x;

catch(ArithmeticException ae) { System.out.println("Hello"); } System.out.println("Nothing done in catch block.");

Output Hello Nothing done in catch block.


Java in Hindi Nested try Statement ge try Statement Block dks Hkh Nested dj ldrs gSaA ge tSls gh ,d try Block ls nwljs try Block esa izos”k djrs gSa] fiNys try Block dh lHkh Information Stack esa Store gks tkrh gSaA ;fn ,d Inner try Block dk catch Block uk gks] rks try Block Outer try ds catch Block dks Exception Throw djrk gSA ;fn dksbZ Hkh Outer catch Block Inner try Block ds Exception dks Handle ugha dj ikrk gS] rks tkok Run Time Environment ml Inner Exception Block ds Exception dks Handle dj ysrk gSA

The throw Keyword vHkh rd geus ftrus Hkh mnkgj.k ns[ks gSa] muesa JRE dksbZ Exception Throw djrk gS vkSj Program dk catch Block ml Exception dks Catch djds Handle djrk gSA blds vykok ge fdlh t:jr dks iwjk djus ds fy, vyx ls Hkh fdlh Exception dks throw Statement dk iz;ksx djds Throw dj ldrs gSaA throw Statement, General Form fuEukuqlkj gksrk gS% throw ThrowableObject;

bl Statement esa ThrowableObject Throwable Class ;k mlds fdlh Sub Class dk Object gksrk gSA Basic Data Types tSls fd int, char, float vkfn vkSj blh rjg ls dksbZ Hkh Non-Throwable Class tSls fd String o Object, bUgsa ge Exceptions dh rjg Use djds Throw ugha dj ldrs gSaA fdlh Throwable Object dks izkIr djus ds nks rjhds gks ldrs gSaA igys rjhds esa fdlh Parameter ds :i esa Throwable Object dks Use fd;k tkrk gS] tSlkfd fiNys mnkgj.kksa esa geus fd;k gS vkSj nwljs rjhds esa new Operator dk iz;ksx djds Throwable Class dk ,d Object Create fd;k tkrk gSA dbZ ckj ge dqN fo”ks’k fLFkfr;ksa esa ge Lo;a dksbZ Exception Throw djuk pkgrs gSa] rkfd Program User ;fn dksbZ xyrh djrk gS] rks ml xyrh dks lq/kkj ldsA mnkgj.k ds fy, ekuyks fd User fdlh Password Form ij Login djrs le; xyr Login ID Enter dj nsrk gS vkSj ge pkgrs gSa fd ;fn User xyr Login ID Enter djs] rks ,d Error Message vkuk pkfg,A bl fLFkfr esa ge Lo;a dk Exception Object Throw dj ldrs gSaA tc ge fdlh fo”ks’k ifjfLFkfr esa viuk Lo;a dk Exception Object Throw djrs gSa] rks throw Statement ds rqjUr ckn Program dk Normal Execution :d tkrk gSA tgka ls fdlh Exception dks Throw dj fn;k tkrk gS] ml Statement ls vkxs ds fdlh Hkh Statement dk Execution ugha gksrk gSA fQj lcls ikl ds try Block dks Check fd;k tkrk gS] fd Throw gksus okys Exception dks Handle djus ds fy, bl try Block dk dksbZ catch Block Match djrk gS ;k ughaA ;fn ml try Block ds fdlh catch Block esa Matching Class dk Exception Holder fey tkrk gS] rks Program Control ml Statement ij Transfer gks tkrk gSA ysfdu ;fn dksbZ Matching catch Block izkIr ugha gksrk gS] rks vxyk try Block Check fd;k tkrk gSA ;fn iwjs Program esa dksbZ Hkh Matching Exception Handler ugha feyrk gS] rks Program Crash gks tkrk gS vkSj JRE dk Default Exception Handler Generated Exception dks Handle djds Program dks Terminate dj nsrk gSA bl iwjh izfØ;k dks ge fuEukuqlkj ,d Program }kjk le> ldrs gSa% 347 Any Question or Suggestion, Just Discuss Here...

Java in Hindi Program import java.io.* ; import java.lang.Exception ; public class gradeTest { public static void main( String[] args ) { try { int firstValue = 100, secondValue = 200; if(firstValue < secondValue) { throw new Exception("First Value is Less then Second Value"); }

}

}

} catch( Exception excp ) { System.out.println( "Exception: " + excp.getMessage() ) ; }

bl Program esa geus try Block esa nks Integer izdkj ds Variables Declare fd, gSa] lkFk gh mUgsa Initialize Hkh dj fn;k gSA fQj ,d if Statement Block esa firstValue Variable ds eku dks secondValue Variable ds eku ls Check djok;k gSA pwafd firstValue esa eku 100 gS] tcfd secondValue esa eku 200 gS] blfy, if Condition True gks tkrh gS vkSj if Statement Block dk Execution gks tkrk gSA bl if Statement Block esa Exception Class dk ,d u;k Object Create fd;k x;k gS vkSj mlds Constructor esa ,d Message dks Store fd;k x;k gSA lkFk gh bl Exception Type ds Object dks Throw fd;k x;k gSA bl Exception dks catch Block esa Catch dj fy;k tkrk gSA catch Block bl Exception dks excp Object esa izkIr djrk gSA getMessage() Method Exception Object excp esa Hold gksus okys ml Message dks Return djrk gS] tks Message geus try Block ds Constructor esa Exception Object dks Provide fd;k gSA blfy, tc bl Program dks Execute djrs gSa rc gesa Output esa fuEukuqlkj ,d Message Display gks tkrk gS% Exception: First Value is More then Second Value

bl Program esa rks geus Super Class Exception dk gh Object Throw fd;k gSA ysfdu ;fn gesa irk gks fd fdlh fo”ks’k fLFkfr esa fdl izdkj dk Exception Generate gks ldrk gS] rks ge Particular ml Sub Class ds Hkh Object Create djds Throw dj ldrs gSa vkSj catch Block esa ml Exception dks Catch dj ldrs gSaA


Java in Hindi The throws Keyword ;fn gesa ,slk yxrk gS fd ge tks External Function ;kuh ,slk Method tks fdlh Class esa Define ugha fd;k tkrk gS] cfYd Class ds ckgj ,d Lora= Method dh rjg Define fd;k tkrk gS] og Method fdlh uk fdlh rjg dk Exception Generate dj ldrk gS] lkFk gh ge ;s Hkh tkurs gSa fd tks Method Exception Generate dj ldrk gS] og Method ml Exception dks Handle ugha djsxk] rks ge ml Method ds Exception dks throws Keyword }kjk fuEukuqlkj Syntax esa Throw dj ldrs gSa% AccessSpecifier ReturnType FunctionName(ParameterList) throws ExceptionList { // Body }

tc ge bl izdkj ds Syntax ls fdlh Exception dks Throw djrs gSa] rc ge ftl Class esa bl Lora= Function dks Use djrs gSa] bl Function ls Generate gksus okys Exception dks Handle djus dh ftEesnkjh Hkh mlh Class ds catch Block dh gks tkrh gSA bl Syntax esa fuEu nks “kCnksa ds vykok iwjk Function Syntax mlh rjg dk gS] ftl rjg dk fdlh vU; lkekU; Member Method dk Definition Syntax gksrk gS% throws ExceptionList

tc dksbZ Function dksbZ Exception Generate djrk gS] rc og Function fofHkUu izdkj ds Exception dks Throw dj ldrk gSA ;gka ge ExceptionList ds LFkku ij mu fofHkUu izdkj ds Exceptions dks Specify dj ldrs gSa] ftUgsa og Method Throw dj ldrk gSA mnkgj.k ds fy, ekuyks fd geus tks Function Create fd;k gS] og Method Arithmetical o Array ls lEcaf/kr Exceptions dks Throw dj ldrk gSA rks bl Function dks ge fuEukuqlkj Define dj ldrs gSa% public void ExceptionTestFunction() throws ArithmeticalException, IllegalAccessException { // Body throw new ArithmeticalException(“This is Arithmetical Exception”);

}

// Body throw new IllegalAccessException(“This is Illegal Access Exception”);

The finally Code Block lkekU;r;k tc Hkh fdlh try Block esa dksbZ Exception Generate gksrk gS] Program Control try Block dks NksMdj lh/ks gh catch Block esa ml Exception dks Handle djus ds fy, pyk tkrk gSA ysfdu dbZ ckj ,slh fLFkfr gksrh gS] fd try Block esa dksbZ Exception Generate gksus ds ckotwn Hkh gesa try Block ds dqN Statements dk Execution djuk t:jh gksrk gSA 349 Any Question or Suggestion, Just Discuss Here...

Java in Hindi mnkgj.k ds fy, ekuyks fd geus try Block esa fdlh File dks Open fd;k vkSj File dks Save djrs le; dksbZ Exception Generate gks x;kA bl fLFkfr esa ge try Block ls Open dh xbZ File dks Close fd, fcuk gh catch Block esa vk tkrs gSaA ysfdu Open dh xbZ File dks Close fd, fcuk ge Program dks Terminate ugha dj ldrs gSa] D;ksafd ,slk djus ij Program esa nwljh izdkj dh leL;k,a iSnk gks ldrh gSaA blfy, ;s t:jh gS fd Exception Generate gksus dh fLFkfr esa Hkh try Block ds dqN ,sls Statements dk Execution gksuk pkfg,] tks catch Block esa Control ds Transfer gksus ds ckn Hkh File dks Close dj ldsa] rkfd System esa vU; izdkj dh Problem uk gksA bl izdkj ds dke ds fy, ge File dks Close djus dk Statement try Block o catch Block nksuksa esa

fy[kdj djrs gSaA

;fn Exception Generate ugha gksrk gS] rks try Block dk File Close djus dk Statement Execute gks dj File dks Close dj nsrk gS vkSj ;fn Exception Generate gks tkrk gS] rks catch Block esa fy[kk x;k File Close djus dk Statement Execute gks tkrk gS] tks File dks Close dj nsrk gSA ;kuh ge le> ldrs gSa fd File Close djus dk dke ,d ,slk dke gS] tks gksuk gh pkfg,A tkok esa dksbZ Program cukrs le; Hkh ge ,sls dkeksa dks r; dj ldrs gSa] tks fdlh Hkh fLFkfr esa gksus gh pkfg, gksrs gSaA pwafd try o catch nksuksa Block esa t:jh :i ls Execute gksus okys Code Statements dks nks ckj fy[kus ls cpus ds fy, tkok esa finally Code Block dh lqfo/kk iznku dh xbZ gSA ;s ,d ,slk Code Block gksrk gS] ftlesa fy[ks x, Statements dk Execution gksrk gh gS] fQj pkgs try Block esa dksbZ Exception Generate gks pkgs uk gksA tkok esa Program Develop djrs le; ,sls ftrus Hkh Statement gksrs gSa] ftUgsa Execute djuk gh gksrk gS] mUgsa finally Block esa fy[k fn;k tkrk gSA fdlh Hkh try/catch Block tksMs esa finally Block gesa”kk lcls vfUre Block gksrk gSA ;kuh ;fn ge Multiple catch Block okyk Program Develop dj jgs gSa] rks ml Program esa Hkh dsoy ,d gh try o ,d gh finally Block gksrk gS] ysfdu mlesa catch Block ,d ls T;knk gks ldrs gSaA try Block gesa”kk lcls igyk Block gksrk gS tcfd finally Block dks lHkh catch Blocks dks Define djus ds ckn esa Define fd;k tkrk gSA bl Block dks ge fuEukuqlkj Use djuk lh[k

ldrs gSa%

Program import java.io.* ; import java.lang.Exception ; public class gradeTest { public static void main( String[] args ) { try { // Comment Next Statement Line for First Output int firstValue = 100, secondValue = 200;

// Line Number 01


Java in Hindi // Un-Comment Next Statement Line for Second Output // int firstValue = 300, secondValue = 200; Line Number 02 if(firstValue < secondValue) { throw new Exception("First Value is More then Second Value"); } if(firstValue > secondValue) { throw new ArithmeticalException("Second Value is Greater."); }

{ }

} catch( ArithmeticalException excp)

System.out.println( "Exception: " + excp.getMessage() ) ;

catch( Exception excp ) { System.out.println( "Exception: " + excp.getMessage() ) ; }

}

}

finally { System.out.println ("This Statement must be executed on any exception."); }

First Output Exception: First Value is Greater then Second Value This Statement must be executed on any exception. Second Output Exception: Second Value is Greatest. This Statement must be executed on any exception.

bl Program ds nks Output crk, x, gSaA First Output izkIr djus ds fy, Program dks T;ksa dk R;ksa Compile djds Run djuk gksrk gSA tcfd Second Output dks izkIr djus ds fy, Program ds try Block ds “Line Number 01” dks Comment cukuk gksrk gS vkSj “Line Number 02” dks Normal Statement cukuk gksrk gSA ge ns[k ldrs gSa] fd nksuksa gh Output esa nwljh Line Common :i ls Display gks jgh gS vkSj bl Line dks geus finally Block esa fy[kk gSA ge ns[k ldrs gSa fd nksuksa gh fLFkfr;ksa esa nks vyx izdkj ds Exception dks Handle djus ds fy, nks catch Block gSa] ysfdu nksuksa catch


Java in Hindi Block esa Exceptions dks Handle djus ds ckn Hkh finally Block ds Statement dk Execution gks jgk gSA

;fn try Block esa fdlh Hkh izdkj dk Exception Generate uk gks] rc Hkh finally Block dk Statement Output esa Display gksrk gh gSA ;kuh finally Block dks ge Sequential Statement Block Hkh dg ldrs gSa] D;ksafd Sequential Statement Block ,sls Statements dk Block gksrk gS] tks gesa”kk gh Execute gksrs gSaA

Types of Exceptions – The Java Built – In Exceptions Classes

Java API ds Methods o tkok Lo;a Hkh fofHkUu izdkj ds Exceptions Throw djrk gSA bu Exceptions dks nks Sub Classes Error o Exception esa foHkkftr fd;k tk ldrk gSA bu nksuksa Sub Classes dks Throwable Super Class ls Derive fd;k x;k gSA Error Class o bldh Sub Classes ,slh fLFkfr;ksa dks Represent djrs gSa] ftUgsa lkekU;r;k Solve ugha fd;k tk ldrk gS vkSj lkekU;r;k ;s gekjs Program dks Terminate gh djrs gSaA Java Developer Kit dh fofHkUu Classes fofHkUu izdkj ds Exception o Error Exceptions Throw djrs gSaA

java.lang Exceptions bl Package esa tkok Language dh T;knkrj vk/kkjHkwr Classes gSa] ftu ij tkok vk/kkfjr gSA bu Classes dks “Core of Java” Language Hkh dgk tkrk gSA RuntimeException Class ls Derive fd, x, fdlh Hkh Method ds lkFk throws Keyword dk iz;ksx djds Exception dks Throw djus dh t:jr ugha gksrh gSA buls Generate gksus okys Exceptions Normal Exceptions dgykrs gSa vkSj lkekU;r;k bu Exceptions dks dksbZ Hkh Method Throw dj ldrk gSA fdlh Program esa Generate gksus okyh os Abnormal fLFkfr;ka ftUgsa Solve fd;k tk ldrk gS] Exception dgk tkrk gS] tcfd ftu fLFkfr;ksa dks Solve ugha fd;k tk ldrk gS] mUgsa Errors dgrs gSaA Exceptions Recoverable gksrs gSa tcfd Errors Non-Recoverable gksrs gSaA fuEu Table esa java.lang Package ls Generate gks ldus okys fofHkUu Exceptions o Errors dks muds Short Description ds lkFk n”kkZ;k x;k gS% The java.lang Exceptions Exception ArithmeticException ArrayIndexOutOfBoundsException ArrayStoreException ClassCastException ClassNotFoundException CloneNotSupportedException Exception

Cause Arithmetic error condition (for example, divide by zero). Array index is less than zero or greater than the actual size of the array. Object type mismatch between the array and the object to be stored in the array. Cast of object to inappropriate type. Unable to load the requested class. Object does not implement the cloneable interface. Root class of the exception hierarchy.


Java in Hindi IllegalAccessException IllegalArgumentException IllegalMonitorStateException IllegalThreadStateException IndexOutOfBoundsException InstantiationException InterruptedException NegativeArraySizeException NoSuchMethodException NullPointerException NumberFormatException RuntimeException SecurityException StringIndexOutOfBoundsException

Class is not accessible. Method receives an illegal argument. Improper monitor state (thread synchronization). The thread is in an improper state for the requested operation. Index is out of bounds. Attempt to create an instance of the abstract class. Thread interrupted. Array size is less than zero. Unable to resolve method. Attempt to access a null object member. Unable to convert the string to a number. Base class for many java.lang exceptions. Security settings do not allow the operation. Index is negative or greater than the size of the string.

The java.lang Errors Error AbstractMethodError ClassCircularityError ClassFormatError Error IllegalAccessError IncompatibleClassChangeError InstantiationError InternalError LinkageError NoClassDefFoundError NoSuchFieldError NoSuchMethodError OutOfMemoryError StackOverflowError ThreadDeath

UnknownError UnsatisfiedLinkError VerifyError VirtualMachineError

Cause Attempt to call an abstract method. This error is no longer used. Invalid binary class format. Root class of the error hierarchy. Attempt to access an inaccessible object. Improper use of a class. Attempt to instantiate an abstract class. Error in the interpreter. Error in class dependencies. Unable to find the class definition. Unable to find the requested field. Unable to find the requested method. Out of memory. Stack overflow. Indicates that the thread will terminate. May be caught to perform cleanup. (If caught, must be rethrown.) Unknown virtual machine error. Unresolved links in the loaded class. Unable to verify bytecode. Root class for virtual machine errors.


Java in Hindi java.io Exceptions java.io Package dh Classes Hkh fofHkUu izdkj ds Exceptions Throw djrh gSa] ftUgsa vkxs FkksMs ls Description ds lkFk n”kkZ;k x;k gSA dksbZ Hkh ,slh Class tks I/O ds fy, Use dh tkrh gS] Recoverable Exceptions Throw dj ldrh gSA mnkgj.k ds fy, fdlh File dks Open djus ;k File esa Write djus dh Process le;≤ ij Fail gksrh jgrh gSA java.io Package fdlh izdkj dk Error Throw ugha djrk gSA The java.io Exceptions Exception IOException EOFException FileNotFoundException InterruptedIOException

Cause Root class for I/O exceptions. End of file. Unable to locate the file. I/O operation was interrupted. Contains a bytesTransferred member that indicates how many bytes were transferred before the operation was interrupted. Malformed UTF-8 string.

UTFDataFormatException

java.net Exceptions ;s Package Network Communications dks Handle djrk gSA ;s Class lkekU;r;k ,sls Exceptions Generate djrk gS] tks Connect Failure ;k blls lEcaf/kr tkudkfj;ka iznku djrs gSaA ;s Package Hkh dksbZ Error Throw ugha djrk gS] ysfdu ;s Package fuEukuqlkj dqN Exceptions Throw djrk gS% The java.net Exceptions Exception MalformedURLException ProtocolException SocketException UnknownHostException UnknownServiceException

Cause Unable to interpret URL. Socket class protocol error. Socket class exception. Unable to resolve the host name. Connection does not support the service.

The java.awt Exceptions bl Class esa ,sls Members gSa ftuesa ls ,d rks Error Throw djrk gS tcfd nwljk Exception Throw djrk gSA ;s Members fuEukuqlkj gSa% •

•

AWTException AWTError

( ;s Class AWT Class dh Exceptions dks Throw djrk gSA ) ( ;s Class AWT Class dh Errors dks Throw djrk gSA )


Java in Hindi The java.util Exceptions bl Package dh Classes fuEu Exceptions Throw djrk gS% • •

EmptyStackException NoSuchElementException

(no objects on stack) (no more objects in collection)

Creating Own Exception Sub Class

gkykafd tkok dh T;knkrj Exception dks Handle djus ds fy, tkok esa igys ls gh fofHkUu izdkj dh Classes miyC/k gSaA ysfdu fQj Hkh ;fn ge pkgsa rks viuh Lo;a dh Hkh Exception Class cuk ldrs gSa] tks fdlh Application ds fdlh veqd Problem dks Solve djus dk dke dj ldrk gSA viuh Lo;a dh Sub Exception Class cukus ds fy, gesa gekjh Sub Class dks tkok dh Built–In Exception Class ls Derive djuk iMrk gSA gekjh Class esa gesa dqN Hkh Implement ugha djuk gksrk gS cfYd System Class igys ls gh tkok esa miyC/k gS] ftlesa fofHkUu izdkj ds Exceptions dks Handle djus dh lqfo/kk,a igys ls gh ekStwn gSaA Exception Class esa mldk Loa; dk dksbZ Hkh Method ugha gSa] cfYd blesa Throwable Class ds gh lHkh Methods miyC/k gSaA vr% gekjh Sub Class esa Hkh Throwable Class ds lHkh Methods miyC/k gks tkrs gSa vkSj os Methods Hkh miyC/k gksrs gSa] ftUgsa ge gekjh vko”;drkuqlkj Create djrs gSaA ge fuEu Program }kjk ,d lkekU; Exception Class Extend djuk o mls Use djuk lh[k ldrs gSa% Program // File Name : OwnException.java class MyException extends Exception{ private String exceptionMessage; MyException(String message){ exceptionMessage = message; }

}

public String toString(){ return "My Exception : " + exceptionMessage; }

class OwnException{ static void sendMessage(String message) throws MyException{ System.out.println("Called sendMessage() Method" ); if(message != "Hello"){ throw new MyException(message); } System.out.println("This is my exception from my class"); } public static void main(String args[]){ try{


Java in Hindi

}

}

sendMessage("Hello"); sendMessage("Buy"); }catch(MyException excp) { System.out.println("Caught from MyException Class : "+excp); }

Output Called sendMessage() Method This is MyException from my class Called sendMessage() Method Caught from MyException Class : My Exception : Buy


Java in Hindi

Java Inheritance For

Code Reusability


Java in Hindi Java Package – Code Reusability

vHkh rd geus ftrus Hkh Chapters ns[ks gSa] mu lHkh esa geus fofHkUu izdkj dh Example Classes Create dh gSaA gj Example Class dk uke Hkh geus vyx&vyx j[kk gSA geus igys Hkh dgk gS fd OOPS dh lcls cMh fo”ks’krk ;gh gS fd ge blds Concepts dks Use djds tc dksbZ Class Create djrs gSa] rks ml Class dks ge ckj&ckj Use dj ldrs gSaA ;kuh OOPS ds Concept ds dkj.k gesa tkok esa Codes ds Reusability dh lqfo/kk izkIr gksrh gSA tkok esa Reusability dh lqfo/kk dks ge nks rjhdksa ls izkIr dj ldrs gSaA igys rjhds esa ge ,d Class dks Inherit djrs gSa vkSj Interfaces dks Implement djrs gSaA bl izfØ;k dks geus fiNys nks v/;k;ksa esa le>k gSA bl izfØ;k esa ge ftl Class dks ftl Program esa Use djuk pkgrs gSa] mlh Program esa Apply djds fdlh Class dks Extend djrs gSaA ;kuh ge lkekU;r;k fdlh Class dh Ability dks c
djrs gSa%

1 fdlh Package esa fLFkr fofHkUu Classes dks ge vklkuh ls Reuse dj ldrs gSaA 2 ,d Package dh Classes nwljs Package dh Classes dh rqyuk esa Unique gksrh gSa] D;ksafd leku izdkj ds dke djus okyh fofHkUu Classes dks ,d gh Package esa Group dj fy;k tkrk gSA ge fdlh Package dh fdlh Specific Class dks ,d Fully Qualified Path }kjk Access dj ldrs gSaA 3 Package gesa ,d ,slk rjhdk iznku djrs gSa] ftlls ge fdlh Class ds lewg dks General Use ds fy, Unavailable dj ldrs gSaA ;kuh Package gesa Classes dks Hide djus dh lqfo/kk nsrk gS] ftldh otg ls ge fdlh vU; Program ;k Package dks fdlh Package dh Internal Classes dks Use djus ls jksd ldrs gSaA 4 Packages gesa ,d ,slk rjhdk Provide djrk gS] ftlls ge Program ds Coding o Design nksuksa dks vyx&vyx j[k ldrs gSaA lcls igys ge fofHkUu izdkj dh Classes dks Design dj ldrs gSa vkSj fofHkUu izdkj dh vU; Classes ls mudh Relationship r; dj ldrs gSa vkSj fQj ge Class ds Methods ds fy, t:jh Codes dks Implement dj ldrs gSaA Packages dh otg ls ,slk Hkh lEHko gksrk gS fd ge fdlh Hkh Method dks fcuk Program ds Design esa Change fd, Modify dj ldrs gSaA T;knkrj Applications esa gesa fofHkUu izdkj dh Classes ds lewg dks Use djuk gksrk gS] tgka ,d izdkj dh Class gekjs Application ds Internal Data dks Represent djrh gSa] tcfd nwljs izdkj dh Classes gekjs Program ds External Representation dks r; djrh gSaA ge


Java in Hindi gekjs Application ls lEcaf/kr Data dks Handle djus ds fy, Loa; dh Classes Hkh cuk ldrs gSa vkSj Application ds User Interface dks Develop djus ds fy, tkok dh Internal Packages ;k Class Library esa fLFkr Classes dks Hkh Use dj ldrs gSaA tc ge gekjh t:jr ds vk/kkj ij Program ds Data dks Manage djus ds fy, Classes Create djds mUgsa fdlh Packages esa Hold djrs gSa] rks bl Package dks User Defined Package dgrs gSa] tcfd tkok dh igys ls Existing Classes dks Java API Packages dgrs gSaA vHkh rd geus ftrus Hkh Packages import Statement }kjk vius fdlh Program esa Import fd, gSa] os lHkh Java API ds Packages gSaA vc ge User Defined Packages dks Create o Use djuk lh[ksaxsA

Naming Conventions

tkok Packages dk uke Standard Java Naming Rules dk iz;ksx djds r; fd;k tk ldrk gSA ;kuh Packages dk uke Lowercase Letter ls “kq: fd;k tkrk gSA blls Users dks ;s lqfo/kk gks tkrh gS fd os Class ds uke o Package ds uke esa vUrj dj ikrs gSa] D;ksafd tkok dh Classes dk uke gesa”kk Capital Letter ls “kq: fd;k gksrk gSA ;kuh ;fn ge fuEukuqlkj ,d Statement fy[krs gSa% double sqrtNumber = java.lang.Math.sqrt(1234);

rks bl Statement esa java.lang Math sqrt()

-

Package dk uke gSA Class dk uke gSA Method dk uke gSA

;s Statement ,d Fully Qualified Class Name Math ds sqrt() Method dks Invoke djrk gSA ge bl Statement esa ns[k ldrs gSa] fd lHkh Packages ds uke Lowercase ls “kq: gks jgs gSa] tcfd Math Class dk uke Capital Letter ls “kq: gks jgk gSA ,d vkSj Statement ns[ksa tks fd fuEukuqlkj gS% java.awt.Point pnts[];

bl Statement esa Hkh java.awt Point

-

Package dk uke gS vkSj Class dk uke gSA

Name Conflict dh Problem uk vk, blds fy, t:jh gS fd lHkh Packages dk uke Unique gksA blfy, gekjs fdlh Package dk uke ,slk ugha gksuk pkfg, tks tkok esa igys ls gh miyC/k gksA ;fn ge Duplicate uke nsrs gSa] rks Run-Time Error Generate gks ldrk gSA

pwafd tkok Internet ds fy, Develop dh xbZ Hkk’kk gS vkSj Internet ij gtkjksa yksx ,d lkFk dke djrs gSa] blfy, Duplicate Package Name dks Avoid djuk ukeqefdu gSA blfy, tkok dks Design djus okyksa us ,d ,slk rjhdk Develop fd;k rkfd Internet ij Hkh dHkh Hkh Name Conflict uk gks vkSj gj Class Unique jgsA blds fy, tkok Developers us 359 Any Question or Suggestion, Just Discuss Here...

Java in Hindi Package ds uke ds vkxs Prefix ds :i esa Domain Name dk iz;ksx djus dh jk; nh gSA

;kuh

falna.betalab.mypackage;

bl Statement esa Falna ,d City dk uke gS vkSj Betalab ml Organization dk uke gS] tgka Class dks Develop fd;k x;k gSA ,d ckr /;ku j[ksa fd ge Packages esa vU; Packages dh Dot Operator dk iz;ksx djds Hierarchy Hkh Create dj ldrs gSaA tSls india.rajasthan.jaipur.pali.falna.betalab.mypackage;

bl Statement esa india, rajasthan, jaipur, pali, o falna Øe”k Hierarchy Form esa gSaA ;kuh india Top Level dk Package gS] ftlds vUnj rajasthan uke dk Package gSA bl rajasthan uke ds Package esa jaipur uke dk o jaipur uke ds Package esa pali uke dk Package gS] ftlesa fQj ls falna uke dk Package gSA bl falna uke ds Package esa betalab uke dk Package gS vkSj vUr esa bl Package esa mypackage uke dk Package gSA

Creating Packages

tkok ds Packages dks ge Subdirectory ds :i esa Hkh eku ldrs gSa] ftlesa vkil esa Related fofHkUu izdkj dh Classes ,d Group ds :i esa Stored gksrh gSaA mnkgj.k ds fy, ;fn ge tkok dh awt Packages dh ckr djsa] rks ;s ,d Subdirectory gS] ftlesa Java esa GUI Create djus ls lEcaf/kr fofHkUu izdkj dh Classes Stored gSaA tkok dk Compiler tkok ds fofHkUu Built-In Packages dks ;kuh vkil esa Related Classes ds lewg dks ,d Subfolder ds :i esa Store djrk gS vkSj tc ge tkok ds Program dks Compile o Run djrs gSa] rc tkok ds Compiler o Interpreter dks irk gksrk gS] fd mls tkok ds Built – In Packages dks dgka ls Access djuk gSA ;fn ge ljy Hkk’kk esa dgsa rks tkok Package vkil esa Related Classes dk ,d lewg ek= gksrk gSA blfy, tkok ds gj Built-In Package dk ,d Subfolder gksrk gS] ftlesa tkok dh fofHkUu Built-In Classes Stored gksrh gSaA tkok ds fofHkUu Packages ds Subfolders src uke dh ,d Zip File ds :i esa gksrs gSa vkSj ;s Zip File JDK uke ds ml Folder esa Stored gksrh gS] tks Folder tkok dks Install djrs le; “C:” Drive ij curk gSA bl Zip File dks Extract djds ge tkok ds fofHkUu Built-In Packages esa Stored fofHkUu Related Classes ds lewg dks ns[k ldrs gSaA pwafd tkok dk gj Package ,d Subfolder gksrk gS] ftlesa fdlh ,d fo’k; ls lEcaf/kr Classes dk lewg gksrk gS] blfy, ;fn ge Hkh gekjh Loa; dh Classes ds lewg dks ,d Package ds :i esa Group djuk pkgrs gSa] rks gesa Hkh ,d Subfolder cukuk gksrk gS] ftlesa fofHkUu izdkj dh vkil esa Related Class Files ds lewg dks Store djuk gksrk gSA tc Hkh ge tkok esa dksbZ Professional Program Create djuk pkgrs gSa] rks ge vius Program ls lEcaf/kr fofHkUu izdkj dh Java Source Files Create djrs gSa vkSj bu Source Files dks fdlh uk fdlh Folder esa Save djrs gSaA 360 Any Question or Suggestion, Just Discuss Here...

Java in Hindi tc tkok bu Source Files dks Compile djrs gSa] rc budh Class File Create gksrh gS] ftUgsa tkok Interpreter Execute djrk gSA vc ;fn ge bu Create dh tkus okyh Source Files esa ls dqN vkil esa Logically Related Files dks fdlh Package ds :i esa Group djuk pkgrs gSa] rks ftl Folder esa ge bu Source Files dks Save djrs gSa] mlh Folder esa gesa ,d Sub Folder cukuk gksrk gS vkSj bl Sub Folder dk uke ogh gksuk pkfg,] tks uke ge gekjs Package dk j[kuk pkgrs gSaA pwafd tkok ,d Case Sensitive Language gS] blfy, Folder dk uke Hkh Case Sensitive fu;e ds vUrxZr gh j[kuk gksrk gS vkSj tc ge bl Folder ds uke dks ,d Package ds :i esa vius Program esa Use djuk pkgrs gSa] rc Hkh gesa Package dk ogh uke Use djuk iMrk gS] tks uke geus vius Subfolder dk fn;k gSA pfy,] bl Concept dks ,d mnkgj.k }kjk le>rs gSaA ekuyks fd geus JDK Install fd;k gSA tc ge JDK dks mldh Default Location ij Install djrs gSa] rc og “C:” ij Install gksrk gSA vc ekuyks fd ge gekjs Program ls lEcaf/kr tkok Source Files dks blh JDK esa MyApplication uke dk ,d Sub Folder Create djds mlesa Save djrs gSaA vc ekuyks fd ge gekjh dqN Files dk ,d Package Create djuk pkgrs gSa vkSj Package dk uke myFirstPackage j[kuk pkgrs gSaA bl fLFkfr esa gesa MyApplication uke ds Folder esa myFirstPackage uke dk ,d Folder Create djuk gksxkA /;ku jgs fd geus bl uke esa ftl rjg ls Case dks Use fd;k gS] mlh rjg ds Case dks gesa gekjh Program File esa bl Package dh Classes dks Access djus ds fy, Hkh Use djuk gksxkA Folder Create djus ds ckn esa vc gesa mu Source Files dks Create djuk gksrk gS] ftUgsa ge vius Package esa Store djuk pkgrs gSaA tc gesa fdlh Class dks fdlh Package esa Store djuk gksrk gS] rc ml Class dh File esa lcls igys gesa ml Package dk mYys[k djuk gksrk gS] ftlesa ge Class dks Store djuk pkgrs gSaA ekuyks fd gesa MyApplication Folder ds myFirstPackage Subfolder esa MyFirstClass uke dh Class dks Store djuk gSA bl Class dks myFirstPackage esa Store djus ds fy, tc ge MyFirstClass Class dks Define djrs gSa] rks Class File esa lcls igys Statement ds :i esa gesa ;s crkuk gksrk gS fd ge Create dh tkus okyh Class dks fdl Package esa Store djuk pkgrs gSaA tkok Compiler dks Package dh Information nsus ds fy, gesa fuEukuqlkj package Keyword Statement dk iz;ksx djuk gksrk gS% package myFirstPackage;

vc ftl Class dks gesa myFirstPackage esa Store djuk gS] ml Class dks gesa bl Statement ds ckn esa Define djuk gksrk gSA ;kuh Program // File Name // Save In

: :

MyFirstClass.java C:\JDK\MyApplication\myFirstPackage

package myFirstPackage;


Java in Hindi class MyFirstClass { void printHello() { System.out.println(“Hello”); } }

ge ns[k ldrs gSa fd geus Class ds lkFk fdlh Access Specifier dk iz;kssx ugha fd;k gSA ;fn ge gekjh Class ds lkFk fdlh Access Specifier dk iz;ksx ugha djrs gSa] rks gekjh Class dsoy myFirstPackage esa fLFkr fofHkUu Classes ds fy, gh Accessible gksxhA ;fn dksbZ vU; Class Program bl Class dks Use djuk pkgsxk] rks og bl Class dks Use ugha dj ik,xkA blfy, gesa bl Class ds lkFk public Access Specifier dk iz;ksx djuk gksxkA tc ge blds lkFk public Access Specifier dk iz;ksx djsaxs] rc bl Package dh fdlh Hkh Public Class dks fdlh Hkh nwljs Package dh dksbZ Hkh Class Access djus esa l{ke gksxhA blh rjg ls ;fn ge Class ds Method ds lkFk Hkh fdlh Access Specifier dk iz;ksx ugha djsaxs] rks gekjh Class ds Methods dsoy mlh Package rd gh Accessible jgsaxsA blfy, gesa gekjh Class ds Member Methods ds lkFk Hkh public Access Specifier dk iz;ksx djuk gksxkA ;kuh gesa bl Code Segment esa fuEukuqlkj Modification djuk gksxk% Program // File Name // Save In

: :


package myFirstPackage; public class MyFirstClass { public void printHello() { System.out.println(“Hello”); } }

vc ;fn ge myFirstPackage Package esa fLFkr MyFirstClass ds Object Create djds Use djuk pkgsa] rks blds fy, ge fuEukuqlkj ,d main() Method Class Create dj ldrs gSa% Program // File Name // Save In

: :

UsingMyFirstClass.java C:\JDK\MyApplication

import myFirstPackage.*; public class UsingMyFirstClass { public static void main(String args[])


Java in Hindi {

}

}

MyFirstClass myObject = new MyFirstClass(); myObject.printHello();

ge ns[k ldrs gSa fd geus Package esa Add dh tkus okyh Class dks rks MyApplication Folder ds myFirstPackage uke ds Sub Folder esa Save djds Compile fd;k gS] tcfd UsingMyFirstClass okyh Source File dks MyApplication uke ds Folder esa Save fd;k gSA geus ,slk blfy, fd;k gS D;ksafd fdlh Hkh Package esa dHkh Hkh main() Method okyh Class dks Store ugha fd;k tk ldrk gS] D;ksafd main() Method dh Class Directly Run gksus okyh Class gksrh gSA myFirstPackage Class esa ge mlh Class dks Store dj ldrs gSa] ftlesa ge myFirstPackage ls Directly nwljs tkok Programs esa Access djuk pkgrs gSaA myFirstPackage uke ds Folder esa Store gksus okyh Classes ,d rjg ls Library Classes cu tkrh gSa] ftUgsa Directly fdlh Hkh Source File esa Import djds Use fd;k tk ldrk gSA bl Program esa geus import Statement }kjk myFirstPackage Package dh lHkh Classes dks fuEukuqlkj Statement }kjk UsingMyFirstClass uke dh Source File esa Import fd;k gS% import myFirstPackage.*;

bl Statement ls myFirstPackage esa Stored lHkh Classes gekjs Program ds fy, Accessible gks tkrh gSaA tcfd ;fn ge dsoy MyFirstClass uke dh Class dks gh bl Package ls vius Program esa Access djuk pkgrs gSa] rks ge fuEukuqlkj import Statement Hkh fy[k ldrs gSa% import myFirstPackage.MyFirstClass;

bl Program esa ge ns[k ldrs gSa fd geus MyFirstClass uke dh Class dks myFirstPackage uke ds Package esa Store fd;k gS vkSj gekjh Current Source File esa ;s Class Defined ugha gS] fQj Hkh ge main() Method esa fuEukuqlkj Statement }kjk bl Class ds Object Create dj ik jgs gSa vkSj ml Object ds Reference esa printHello() uke ds Method dks Hkh Access dj ik jgs gSa] tks fd MyFirstClass dk Method gSA ,slk blhfy, lEHko gS] D;ksafd ;s Class gesa myFirstPackage uke ds Package ls izkIr gks jgh gSA ;fn ge pkgsa rks vc bl Package dks fdlh Hkh vU; Program esa import Statement }kjk Use dj ldrs gSaA lkFk gh ge bl Package esa vkSj Classes Hkh Add dj ldrs gSaA blds fy, gesa dsoy bruk gh djuk gksxk fd ftl fdlh Hkh Class dks ge bl Package esa Store djuk pkgrs gSa] ml Package dks gesa public cukuk gksxk vkSj ml Class ls igys gesa package Statement }kjk ;s crkuk gksxk fd ge gekjh Class dks fdl Package esa Store djuk pkgrs gSaA


Java in Hindi blh rjg ls tc gesa ml Package dh Class dks Access djuk gksxk] rc gesa import Statement }kjk ml Package dks ;k ml Package dh fdlh Class dks viuh Source File esa Import djuk gksxkA ;kuh ;fn ge pkgsa rks fuEukuqlkj ,d vkSj Class bl Package esa Store dj ldrs gSa% Program // File Name // Save In

: :

MySecondClass.java C:\JDK\MyApplication\myFirstClass

package myFirstPackage; public class MySecondClass { public void printBuy() { System.out.println("Huy and Buy"); } }

bl Class dks Hkh myFirstPackage Folder esa Save djds Compile djus ij bl Package esa bldh Hkh Class File Create gks tkrh gSA vc ge fuEukuqlkj ,d main() Method Program esa bl Package dh nksuksa Classes ds Objects Create djds mUgsa Use dj ldrs gSa% Program // File Name // Save In

: :


import myFirstPackage.*;

//For importing all classes of the package

public class UsingMyFirstClass { public static void main(String args[]) { MyFirstClass myObject1 = new MyFirstClass(); MySecondClass myObject2 = new MySecondClass(); myObject1.printHello(); myObject2.printBuy(); } } Output Hello Huy and Buy

,d ckr /;ku j[ksa fd ge ftl Package dks Create dj jgs gSa] og Package Directory ml Directory dh Subdirectory gksuh pkfg,] ftlesa ge ml Create dh tkus okyh Package dh Classes dks Import djus okyh Source Files dks Save djsaxsA ;fn ge mu Source Files


Java in Hindi dks fdlh nwljh Directory esa Store djrs gSa] tgka Import dh tkus okyh Package dh Subdirectory miyC/k ugha gS] rks ge ml Package dks vius Source Program esa Use ugha dj ldrs gSaA ljy “kCnksa esa dgsa rks ftl Source File esa ge Package dks Use dj jgs gSa] og Package Directory Source Files dh Directory dh Subdirectory gksuh pkfg,A ;fn ge Packages dh Hierarchy Create djuk pkgrs gSa] rks Package dh Hierarchy dh Files dks Access djus ds fy, gesa Dot Operator dk iz;ksx djuk iMrk gSA ekuyks fd gekjh myFirstPackage esa ,d vkSj Sub Package mySecondPackage gS] rks bl Package dh Subdirectory dks gesa myFirstPackage dh Subdirectory esa Create djuk gksxk vkSj bl Sub Package esa Classes dks Save djds Compile djuk gksxkA Class Files dks Sub Package esa Hkstus ds fy, gesa fuEukuqlkj Statement fy[kuk gksxk% Program // File Nam :MyThirdClass.java // Save In :C:\JDK\MyApplication\myFirstPackage\mySecondPackage package myFirstPackage.mySecondPackage; public class MyThirdClass { public void printOK() { System.out.println(“OK”); } }

blh rjg ls fdlh Sub Package dh Class dks Access djus ds fy, Hkh gesa fuEukuqlkj Dot Operator dk iz;skx djds Classes dks viuh Source File esa import djuk gksrk gS% Program // File Name // Save In

: :


import myFirstPackage.mySecondPackage.*; public class UsingMyThirdClass { public static void main(String args[]) { MyThirdClass myObject3 = new MyThirdClass();

}

}

myObject3.printOK();


Java in Hindi ge ,d gh Class Definition File esa ,d ls T;knk Classes dks Define djds mls fdlh Package esa Store dj ldrs gSaA ,sls esa ml Class Definition File esa dsoy ,d gh public Class gksrh gS vkSj tks Class Public gksrh gS] Class Definition File dk uke Hkh ogh gksrk gS] tks ml Public Class dk gksrk gSA ;kuh ;fn ge mijksDr rhuksa Classes dks ,d gh ckj esa ,d gh Class Definition File }kjk myFirstPackage Package esa Store djuk pkgsa] rks fuEu Class File dks myFirstPackage esa Save djds ;s dke dj ldrs gSa% Program // File Name: // Save In :


package myFirstPackage; public class MyFirstClass{ public void printHello(){ System.out.println("Hello"); } } class MySecondClass{ public void printBuy(){ System.out.println("Huy and Buy"); } } class MyThirdClass{ public void printOK(){ System.out.println("OK"); } }

tSlkfd ge bl Class File esa ns[k ldrs gSa] blesa dsoy ,d gh Public Class gSA blfy, ;fn ge Packages ds vykok fdlh vU; Class esa MyThirdClass dk Object Create djuk pkgsa] rks ugha dj ldrs gSa] D;ksafd ;s Public ugha gSA MyThirdClass dks Public Form esa Package esa Add djus ds fy, gesa MyThirdClass dks Package esa vyx ls Store djuk gksxk vkSj blds fy, vyx ls Class File cukuh gksxhA Access Specifier ds lEca/k esa gesa gesa”kk lko/kku jguk pkfg,A ge fdlh Package dh Public Classes dks gh fdlh Outside Package Class esa Directly Access dj ldrs gSaA Package gesa”kk ,d Container dh rjg dke djrk gS] blfy, bldh Classes dks ;fn gesa vU; Classes esa Use djuk gS] rks Package dh bu Classes dk Public gksuk t:jh gksrk gSA tks Classes Public ugha gksrh gSa] mUgsa dsoy mlh Package dh vU; Classes }kjk gh Access fd;k tk ldrk gSA Packages dk iz;ksx gesa”kk Classes o vU; Sub Packages dks Store djus ds fy, ,d Container dh rjg fd;k tkrk gSA tcfd Classes dk iz;ksx Data Members o Methods


Java in Hindi dks Store djus ds fy, fd;k tkrk gSA blfy, Class Members ds lkFk private, protected, public ;k Default Access Specifier dk iz;ksx fd;k tk ldrk gSA tc ge fiNys mnkgj.k dh rjg ,d gh File ls dbZ Classes dks Package esa Add djrs gSa] rc Public Class ds vykok lHkh Classes dsoy mlh Package dh vU; Classes ds fy, gh Accessible gksrh gSa vkSj ;s Classes Package ls ckgj dh Classes ds fy, Hidden jgrh gSaA blfy, ge fdlh ,slh Class esa buds Object Create ugha dj ldrs gSa] tks bl Package ls ckgj gksA


Java in Hindi

Java Multithreaded Programming


Java in Hindi Java Multithreaded Programming

T;knkrj Computer Games esa Graphics o Sounds dk iz;ksx gksrk gSA fdlh Hkh Game esa Graphics, Sounds o Score lHkh dqN ,d lkFk fn[kkbZ nsrs gSaA ekuyks fd Game esa lcls igys Screen Change gks fQj Score Update gks vkSj vUr esa Music lqukbZ ns] rks Game dSlk yxsxkA tkfgj lh ckr gS fd ,slk gksus ij gesa Game vPNk ugha yxsxkA fdlh Hkh Game ds ;s fgLls ,d lkFk Process gksrs gSaA nwljs “kCnksa esa dgsa] rks ,d Program rhu Sub Programs esa Divided gS] vkSj gj Sub Program dks ,d Thread }kjk Handle fd;k tkrk gSA tkok ,d ,slh Programming Language gS] tks Multithreading Technique dks Support djrk gSA ,d ,slk Program ftlesa dbZ Sub Programs gksa vkSj gj Sub Program ,d lkFk Execute gksrk gks] Multithreaded Program dgykrk gSA Multithreading Multitasking dk gh ,d fof”k’V :i gSA Multitasking ls ge lHkh ifjfpr gSaA vkt ftrus Hkh Operating Systems miyC/k gSa] os lHkh Multitasking Operating Systems gSaA ge Multitasking dks Hkh Process Based Multitasking o Thread Based Multitasking

nks Hkkxksa esa ckaV ldrs gSaA bu nksuksa ds chp dk vUrj le>uk dkQh t:jh gSA

fdlh Computer esa ,d le; ij ftrus Hkh Programs Execute gks jgs gksrs gSa] Operating System dh Hkk’kk esa os lHkh Process dgykrs gSaA Process Based Multitasking ,d ,slk Feature gS] ftlds dkj.k ,d Computer esa ,d gh le; esa ,d ls T;knk Programs Run gks ldrs gSaA mnkgj.k ds fy, ftl le; ge fdlh Word Processor esa Typing dj jgs gksrs gSa] mlh le; ge fdlh Song dks Hkh Play dj ldrs gSaA Process Based Multitasking esa ,d Program og Smallest Unit gksrk gS] ftls Operating System dk Scheduler Processor ij Dispatch djds Process djrk gSA Thread Based Multitasking Environment esa fdlh Program dk ,d Thread og Smallest Unit gksrk gS] ftls Operating System dk Scheduler Processor ij Process djus ds fy, Dispatch djrk gSA bldk eryc ;s gqvk fd ,d Single Program ,d ls T;knk Tasks dks leku le; esa leku :i ls Execute dj ldrk gSA

mnkgj.k ds fy, ,d Song Player esa Song Play gks jgk gksrk gS] mlh le; ge fdlh nwljs Song dks Song Player esa vxys Song ds :i esa Play gksus ds fy, Select Hkh dj ldrs gSaA lkFk gh Song Play gksrs le; gh ge Song ds Tempo dks Hkh Change dj ldrs gSa vkSj Volume dks Hkh de ;k T;knk dj ldrs gSaA ;s lHkh dke Thread Based Multitasking ds dkj.k gh lEHko gks ikrs gSaA Multitasking Processes dh rqyuk esa Multitasking Thread T;knk ljy gksrs gSaA Processes Heavyweight Tasks gksrs gSa ftUgsa Separate Address Spaces dh t:jr gksrh gSA ,d Process ls nwljs Process ij Move gksus ;kuh Context Switching Hkh Costly gksrk gSA tcfd Threads Lightweight Tasks gksrs gSa vkSj ,d Program ds lHkh Threads leku Address Space dks Share djrs gSaA lkFk gh lHkh Threads leku Heavyweight Process dks Hkh Share djrs gSaA


Java in Hindi gkykafd tkok Process Based Multitasking dks Use djrk gS] ysfdu fQj Hkh tkok esa Process Based Multitasking Programs Develop ugha fd, tk ldrs gSa] fQj Hkh tkok Multithreading Based Multitasking dks Support djrk gSA Multithreading dh Techniques gesa ,sls Programs Write djus dh lqfo/kk nsrk gS] ftuls ge CPU dk Maximum Use dj ldrs gSa] D;ksafd bl rduhd esa Processor ds Idle Time dks Minimum j[kk tkrk gSA ;s O;oLFkk eq[; :i ls Interactive Network Based Applications ds fy, cgqr mi;ksxh gksrh gS] D;ksafd tkok mlh Environment esa dke djrk gS] tgka Idle Time cgqr T;knk gksrk gSA

mnkgj.k ds fy, Network ij Data ds Transmission dh xfr CPU ij Data ds Process gksus dh xfr dh rqyuk esa cgqr gh /kheh gksrh gSA fdlh Single Threaded Program esa gesa ,d Second Task ds “kq: gksus ls igys First Task ds lekIr gksus dk Wait djuk iMrk gS] fQj pkgs CPU Idle Mode esa gh D;ksa uk gksA Multithreading dh rduhd gesa CPU ds bl Idle time dks Utilize djus dh lqfo/kk iznku djrk gSA

Java Thread Model

tkok dk Run-Time System dbZ phtksa ds fy, Threads ij fuHkZj djrk gS vkSj tkok dh lHkh Class Libraries dks Multithreading Techniques dks fnekx esa j[k dj Develop fd;k x;k gSA okLro esa tkok Threads dk iz;ksx iwjs tkok Environment dks Synchronize djus ds fy, djrk gSA ;s izfØ;k CPU ds Idle Time dks Use djus esa gksus okyh Inefficiencies dks de djrk gSA Single Threaded Systems esa Event Loop With Polling dk rjhdk Use fd;k tkrk gSA bl Model esa Controls dk ,d Single Thread ,d Infinite Loop esa Run gksrk gSA Polling ,d Single Event Queue gksrk gS] tks ;s r; djrk gS fd Next D;k djuk gSA ,d ckj tc ;s Polling Mechanism fdlh Signal ds lkFk Return gksrk gS] mnkgj.k ds fy, Network dh File Ready gS] bl Signal ds lkFk Polling Mechanism Return gksrk gS] rc Event Loop Control dks Appropriate Event Handler ij Dispatch dj nsrk gSA tc rd ;s Event Handler Return ugha gksrk gS] rc rd System esa dksbZ Hkh nwljk dke ugha gks ldrk gSA ;gha ij CPU dk Time Waste gksrk gSA bldk ge ;s ifj.kke Hkh izkIr dj ldrs gSa fd Program dk dsoy ,d gh Event lkjs System dks Use dj jgk gS vkSj fdlh vU; Events dks Process djus ls jksd jgk gSA

lk/kkj.krkSj ij fdlh Single Threaded Environment esa tc ,d Thread fdlh Resource dk Wait djrk gS] rc og Suspend Mode esa pyk tkrk gS vkSj tc rd Program dk og Thread fdlh Resource dk Wait djrk jgrk gS] rc rd iwjk Program Stop Mode esa jgrk gSA tkok ds Multithreading dk Qk;nk ;s gS fd blesa Main/Polling Loop ds Mechanism dks Eliminate dj fn;k x;k gSA blesa fdlh Program dk ,d Thread Program ds fdlh nwljs Thread dks Stop fd, fcuk fdlh System Resource dks izkIr djus ds fy, Suspend Mode esa Pause gks ldrk gSA mnkgj.k ds fy, ftl le; Network ls dksbZ File Read gks jgh gksrh gS ;k ftl le; Program dk dksbZ fgLlk User ds Input dk Wait dj jgk gksrk gS] ml le; Program esa 370 Any Question or Suggestion, Just Discuss Here...

Java in Hindi fdlh Image dh Processing dk dke ;k Animation ds Animate gksus dk dke Continue jg ldrk gSA bl le; esa Hkh CPU dksbZ uk dksbZ nwljk dke djrk jgrk gS vkSj dsoy og Thread gh Suspend jgrk gS] ftls fdlh System Resource dh t:jr gksrh gSA ,d Thread dbZ fLFkfr;ksa esa gks ldrk gSA ,d Thread Running Mode esa gks ldrk gSA tSls gh ,d Thread dks CPU dk Time feyrk gS] og Run gksus dh fLFkfr ;kuh Ready to Run gks ldrk gSA dksbZ Running Thread Suspend gksdj viuh Current Activity dks dqN le; ds fy, Pause dj ldrk gSA ,d Suspended Thread dks ;s crk dj fd mls dgka fQj ls viuk dke pkyw djuk gS] og Thread Resume gks ldrk gSA fdlh Hkh le; dksbZ Thread Terminate gks ldrk gS] ftlls ml Thread dk Execution rqjUr Halt gks ldrk gSA ,d ckr /;ku j[ksa fd ,d Thread tc ,d ckj Terminate gks tkrk gS] rc ogh Thread okil Resume ugha gks ldrkA

Thread Priorities

tkok gj Thread dks ,d Priority iznku dj nsrk gS] ftlls ;s r; gks tkrk gS fd ,d Thread nwljs Thread dh rqyuk esa fdl izdkj ls Treat gksxkA Thread Priorities Integer eku gksrs gSa tks Relative Thread dh ,d nwljs ls Priority dks r; dj nsrs gSaA ,d Absolute Value ds :i esa Priority dk eku Meaningless gksrk gSA ,d Higher Priority dk Thread Lower Priority ds Thread dh rqyuk esa fdlh Hkh rjg ls rst xfr ls Run ugha gksrk gSA blds ctk; Thread Priority ;s r; djrk gS fd fdl Thread ds ckn dkSulk Thread Run gksxkA bl izfØ;k dks Thread Context dgrs gSaA

The Thread Class and the Runnable Interface

tkok dk Multithreading System Thread Class] mlds Methods o Runnable Interface ij vk/kkfjr gksrk gSA ,d Thread esa Execute gksus okyk Sub Program Encapsulated gksrk gSA pwafd tkok esa ge fdlh Hkh Running Thread dh fLFkfr dks Refer ugha dj ldrs gSa] blfy, gesa blds Proxy ;kuh Thread Class dks Extend djds mlds Objects ds lkFk Deal djuk gksrk gSA ,d u;k Thread Create djus ds fy, gesa Thread Class dk Sub Class Create djuk gksrk gS ;k fQj Runnable Interface dks Implement djuk gksrk gSA Thread Class esa cgqr lkjs Methods gksrs gSa] ftudk iz;ksx Threads dks Manage djus ds fy, fd;k tkrk gSA

The Main Thread

tc ,d tkok Program Start gksrk gS] rks rqjUr gh ,d tkok Thread Run gksus yxrk gSA bl lcls igys Run gksus okys Thread dks tkok esa Main Thread dgrs gSa] D;ksafd ;gh og igyk Thread gksrk gS] tks Program ds Start gksrs gh Run gksus yxrk gSA Main Thread nks dkj.kksa dh otg ls cgqr Important gS% 1 ;gh og Thread gksrk gS] ftlesa vU; Child Thread Swap gksrs gSaA 2 lkekU;r;k ;gh og vfUre Thread Hkh gksrk gS] tks Program dks Shut Down djus ls lEcaf/kr fofHkUu izdkj ds Finalization Tasks Perform djrk gSA


Java in Hindi gkykafd tc gekjk Program Start gksrk gS] rc ;s Thread Automatically Create gksrk gS] fQj Hkh bls ,d Thread Object }kjk Control fd;k tk ldrk gSA ,slk djus ds fy, gesa bl Thread dk ,d Reference izkIr djuk gksrk gSA bl Thread dk Reference izkIr djus ds fy, gesa currentThread() Method dks Call djuk gksrk gS] tks fd Thread Class dk ,d Public o Static Method gSA bl Method dk Syntax fuEukuqlkj gksrk gS% static Thread currentThread();

;s Method ml Thread dk Reference Return djrk gS] ftlesa bl Method dks Call fd;k tkrk gSA ,d ckj tc gesa Main Thread dk Reference izkIr gks tkrk gS] mlds ckn ge bl Thread dks Hkh mlh rjg ls Control dj ldrs gSa] ftl rjg ls fdlh vkSj Thread dks Control djrs gSaA pfy,] bl izfØ;k dks ,d mnkgj.k }kjk le>us dh dksf”k”k djrs gSa% Program // File Name : ControllingTheMainThread.java class ControllingTheMainThread { public static void main(String args[]) { Thread mainThread = Thread.currentThread(); System.out.println(“Current Thread : “ + mainThread); // Change the name of the thread mainThread.setName(“MyThread”); System.out.println(“After Changing the Name : “ + mainThread); try {

}

}

for(int i=5; i>0; i--) { System.out.println(i); Thread.sleep(1000); }

} catch(InterruptedException excp) { System.out.println(“Main Thread Interrupted”); }

Output Current Thread : Thread[main,5,main] After Changing the Name : Thread[MyThread,5,main] 5 4 3 2 1 372 Any Question or Suggestion, Just Discuss Here...

Java in Hindi bl Program esa currentThread() Method dks Call djds Current Thread ;kuh main Thread dk Reference izkIr fd;k x;k gS vkSj bl Reference dks ,d Local Thread Object mainThread esa Store fd;k x;k gSA faQj Program main Thread dh Information Display djrk gSA fQj Program main Thread ds Internal uke dks Change djus ds fy, setName() Method dks Call djrk gSA fQj main Thread dh Information dks fQj ls Display fd;k x;k gSA fQj ,d Loop 5 ls 1 rd fxurh Count djrk gS vkSj gj Counting esa sleep() Method }kjk ,d Second dk le; ysrk gSA sleep() Method esa Argument ds :i esa Milliseconds esa eku fn;k x;k gSA /;ku nsa fd Loop dks try/catch Block esa Define fd;k x;k gS] D;ksafd Thread esa sleep() Method InterruptedException throw dj ldrk gSA ;s Exception rc Throw gks ldrk gS] tc dksbZ nwljk Thread bl Sleeping dks Interrupt djuk pkgrk gSA bl Program esa ;fn dksbZ Exception Generate gksrk gS] rks ;s Program dsoy ,d Message Display djrk gS] tcfd fdlh Real Program esa gesa bl Exception dks Bhd ls Handle djuk t:jh gksrk gSA bl Program ds Output esa ge ns[k ldrs gSa fd geus Thread izdkj ds Object mainThread dks println() Method esa Argument ds :i esa Pass fd;k gS vkSj tc ;s Object Output esa Print gksrk gS] rc ;s ,d Øe esa Display gksrk gSA ;s Øe fuEukuqlkj gS% Thread [ThreadName, TreadPriority, ThreadGroupName] By Default main Thread dk uke main gSA bldh Priority 5 gS tks fd Default Value gS vkSj main ml Group dk uke gS] ftldk main Thread ,d lnL; gSA Thread Group ,d Data Structure gS] tks Threads ds Collections dh fLFkfr dks Control djrk gSA bl Process dks tkok ds Run Time Environment }kjk Handle fd;k tkrk gSA

pfy,] bl Program esa Use fd, x, Methods dks FkksMk vkSj le>us dh dksf”k”k djrs gSaA sleep() Method ml Thread dks Argument esa fn, x, Milliseconds rd ds le; ds fy, Suspend Mode esa ys tkrk gS] ftlds fy, bl Method dks Call fd;k x;k gSA bl Method dk Syntax fuEukuqlkj gksrk gS% static void sleep(long milliseconds) throws InterruptedException sleep() Method dk ,d nwljk :i Hkh gS] tks gesa Periods dks Milliseconds o Nanoseconds esa Specify djus dh lqfo/kk nsrk gSA bl Method dk Syntax fuEukuqlkj gS% static void sleep(long milliseconds, long nanoseconds) throws InterruptedException

;s Method rHkh mi;ksxh gksrk gS] tc Environment Nanoseconds ftrus NksVs Period dks Support djrk gksA fiNys mnkgj.k esa geus ns[kk fd ge setName() Method dk iz;ksx djds Thread dk uke Set dj ldrs gSa vkSj getName() Method dk iz;ksx djds Thread dk uke izkIr dj ldrs gSaA ;s Methods Thread Class ds Members gSa vkSj bl Class esa bUgsa fuEukuqlkj Declare fd;k x;k gS%


Java in Hindi final void setName(String threadName) final String getName()

;gka threadName ml Thread dk uke gS] ftldk uke cnyuk gSA

Two Kinds of Threads

tkok esa ge nks rjg ds Threads Create dj ldrs gSaA lcls ljy rjhdk rks ;gh gS fd fdlh Hkh Existing Class dks ysa vkSj mls Thread esa Convert dj nsaA ge ,slk djus ds fy, Class dks bl rjg ls Modify dj ldrs gSa] fd og Runnable Interface dks Implement djs] ftlesa run() uke dk ,d Method gksrk gS] ftldh t:jr lHkh Threads dks gksrh gSA run() Method esa os Codes fy[ks tkrs gSa] ftUgsa ,d Thread Execute djrk gSA Thread Create djus ds nwljs rjhds esa gesa tkok dh Thread Class dks Derive djds ,d Completely Separate Class Create djuh gksrh gSA D;ksafd ,d Thread Class Lo;a gh Runnable Interface dks Implement djrk gS] blfy, blesa igys ls gh ,d run() Method

gksrk gSA

gkykafd ;s run() Method dqN Hkh ugha djrk gSA blfy, gesa vDlj bl Method dks viuh Derived Class esa Override djuk gksrk gS] rkfd ge mu lHkh Coding dks ml Thread esa fy[k ldsa] ftUgsa Thread ds Execution ds lkFk Execute djuk gSA

Converting a Class to a Thread fdlh Class dks ,d Thread esa Convert djus ds fy, tc ge igyk jkLrk pqurs gSa] rc gesa dbZ dke djus gksrs gSaA blesa gesa ,d ,slh Class Create djuh gksrh gS] tks Runnable Interface dks Implement djrk gksA tc ge fdlh Class esa Runnable Interface dks Implement djrs gSa] rc og Class ,d Thread esa Convert gks tkrh gSA fdlh Class dks Thread esa Convert djus ds fy, gesa fuEu Øe esa dke djuk gksrk gS% 1 ,d Class dks Declare djrs le; mlesa Runnable Interface dks Implement djus dk Statement fy[kk tkrk gSA 2 fQj ml Class esa Runnable Interface ds run() Method dks Implement fd;k tkrk gS] tks fd Runnable Interface dk Only Method gksrk gSA 3 fQj Thread Class ds ,d Object dks Data Member dh rjg blh Class esa Declare fd;k tkrk gSA 4 fQj Thread Class dk Object Create djds mlds Reference esa start() Method dks Call fd;k tkrk gSA vkSj 5 vUr esa Thread dk dke lekIr gks tkus ds ckn Thread dk stop() Method Call fd;k tkrk gSA pfy,] bu lHkh Steps dks FkksMk foLrkj ls le>rs gSaA


Java in Hindi Declaring the Class as Implementing the Runnable Interface fdlh Regular Class dks ,d Thread esa Convert djus ds fy, gesa ml Class esa Runnable Interface dks Implement djuk gksrk gSA mnkgj.k ds fy, ekuyks fd gekjs ikl fuEukuqlkj ,d igys ls Existing Applet Class gS% public class MyApplet extends Applet { // Body of the class. }

bl Class dks Thread esa Convert djus ds fy, gesa blesa Runnable Interface dks fuEukuqlkj Implement djuk gksrk gS% public class MyApplet extends Applet implements Runnable { // Body of the class. }

blh rjg ls ;fn gesa fdlh vU; lk/kkj.k Class dks Thread esa Convert djuk gks] rks ge ;s dke fuEukuqlkj dj ldrs gSa% public class MyFirstThread implements Runnable { // Body of the class. }

Implementing the run() Method fiNys Statement }kjk ge tkok Compiler dks ;s crk nsrs gSa fd ge Class esa Runnable Interface dks Implement djds bl Class dks Thread esa Convert dj jgs gSa] blfy, gesa bl Class esa Runnable Interface ds lHkh Methods dks Implement djuk t:jh gks tkrk gSA pwafd Runnable Interface esa run() uke dk dsoy ,d gh Method gS] blfy, Create dh tk jgh bl Class esa gesa dsoy blh Method dks Implement djuk gksrk gSA bl Method dk Syntax fuEukuqlkj gksrk gS% public void run() { // Thread’s Executables codes goes here. }

bl Method esa gesa mu Codes dks fy[kuk gksrk gS] ftUgsa ge Thread ds :i esa Execute djuk pkgrs gSaA run() Method ,d cgqr gh egRoiw.kZ Method gSA ;s Method fdlh Hkh vU; Method dks Call dj ldrk gS vkSj fdlh Hkh Class dks Use dj ldrk gSA lkFk gh ;s fofHkUu izdkj ds Variables Hkh Declare dj ldrk gSA


Java in Hindi ;kuh run() Method Bhd mlh rjg ls os lkjs dke dj ldrk gS] tks dke ,d main() Method djus esa l{ke gksrk gSA vUrj dsoy bruk gS fd main() Method Execute gksus okyk lcls igyk Thread gksrk gS] tks vU; Threads dks lekukUrj :i ls Run dj ldrk gS] tcfd run() Method vU; lekukUrj Threads ds fy, Entry Point Establish djrk gSA ;kuh lHkh Threads dk Execution run() Method ls gh gksrk gS vkSj Thread rHkh Terminate gksrk gS tc run() Method Terminate gksrk gSA tc ge gekjs u, Thread dks Start djrs gSa] rc tkok Thread ds run() Method dks gh Call djrk gS] blfy, gesa fdlh Tread }kjk Perform gksus okys lHkh dkeksa ds Statements dks run() Method esa gh fy[kuk gksrk gSA run() Method okLro esa fdlh Program ds ,d Sub Program dh rjg dke djrk gS] blfy, run() Method esa ge os Code Statements fy[krs gSa] ftUgsa ge lkekukUrj :i ls Execute djuk pkgrs gSaA bl run() Method dks MyFirstThread Class esa fuEukuqlkj Implement fd;k tk ldrk gS% Program class MyFirstThread implements Runnable { // This is the entry point of the second thread. public void run() { try { for(int i=0; i<5; i++) { System.out.println("Child Thread : " + i); Thread.sleep(1); } } catch(InterruptedException excp) { System.out.println("Child Thread Interrupted"); } System.out.println("Exiting Child Thread"); } }

bl Class esa geus Runnable Interface dks Implement djus ds fy, run() Method dks Define fd;k gSA run() Method esa geus try/catch Block dk iz;ksx fd;k gSA geus ,slk blfy, fd;k gS] D;ksafd bl Method esa geus Thread Class ds sleep() Method dks Use fd;k gS vkSj ;s Method ml le; ,d Exception Generate djrk gS] tc dksbZ nwljk Thread bl Class ds Thread dks Interrupt djus dh dksf”k”k djrk gSA sleep() Method Thread, Super Class dk ,d ,slk Method gS] ftlesa ge Argument ds :i esa Milliseconds dh la[;k Specify djrs gSa vkSj ge ftruh la[;k Specify djrs gSa] tkok Compiler mrus le; rd Suspend Mode esa pyk tkrk gS vkSj run() Method ds vxys Statement dks rc Execute djrk gS] tc Suspend Mode ls okil Normal Mode esa vkrk gSA


Java in Hindi fdlh Hkh Thread ds Suspend Mode dh fLFkfr og fLFkfr gksrh gS] ftl le; dksbZ nwljk u;k Thread Start gks ldrk gS] ;k dksbZ Running Thread CPU ij Swap gks ldrk gSA bl Program esa geus 1 Millisecond ds fy, for Loop dks Suspend Mode esa Hkstk gS] rkfd bl 1 Millisecond ds le; esa tkok fdlh nwljs Thread ds Statements dks Run dj ldsA MyFirstClass Thread rc Terminate gksrk gS] tc run() Method esa fy[ks x, lHkh Statements Execute gks tkrs gSa ;k fdlh vkSj rjhds ls Thread dks Terminate dj fn;k tkrk gSA

Declaring a Thread Object run() Method dks Define djus ds ckn gesa bl Class esa Thread Class dk ,d Object Create djuk gksrk gSA ;s dke ge fuEukuqlkj Statement }kjk djrs gSa% Thread myThread;

;s Thread Object ml Thread dk Reference Hold djrk gS] ftlls fdlh Applet ;k Application Class dks Associated djuk gksrk gSA ge Create fd, x, gekjs Thread Class ds Methods dks blh Object ds lkFk Access dj ikrs gSaA Thread Class gekjs }kjk Create dh tkus okyh fdlh Hkh Sub Thread Class dk Super Class gksrk gSA blfy, ge Thread Super Class ds Reference esa mldh fdlh Hkh Sub Class ds Object dk Reference Store dj ldrs gSaA Creating and Starting the Thread Object vc gesa os Codes fy[kus gksrs gSa] tks ,d Thread dks Create djrs gSa vkSj mls Run djrs gSaA Thread Class esa cgqr lkjs Constructors Defined gSaA muesa ls ,d fuEukuqlkj gS] ftldk ge lcls T;knk mi;ksx djrs gSa% Thread(Runnable threadObject, String threadName);

bl Constructor esa threadObject ml Class dk Object gS] ftlesa Runnable Interface dks Implement fd;k x;k gSA ;s Object Define djrk gS fd fdl Thread dk Execution “kq: djuk gSA tc ge fdlh Thread dks Run djuk pkgrs gSa] rc ml Thread dk ,d Object Create djrs gSa vkSj ml Object dk Reference bl threadObject esa Pass dj nsrs gSaA ,slk djus ij og Thread Run gksus yxrk gS] ftldk Reference threadObject uke ds Parameter esa gksrk gSA ge ftl u, Thread dks bl Constructor }kjk Run djuk pkgrs gSa] mldk ,d uke Hkh Specify dj ldrs gSaA u, Thread dk uke threadName Parameter esa Specify fd;k tkrk gSA ekuyks fd gesa MyFirstThread Class ds Thread dks Run djuk gSA bl fLFkfr esa ge ftl Class esa Runnable Interface dks Implement dj jgs gSa] mlh Class esa ,d Data Member dh rjg fuEukuqlkj Thread Super Class dk ,d Object Create djuk gksrk gS% Thread childThread;


Java in Hindi vc bl Thread Super Class ds Reference Holder Object esa tc ge fuEukuqlkj MyFirstThread Class ds Thread Object dk Reference nsrs gSa] rks tkok Compiler ml MyFirstThread Thread ds run() Method dks Execute dj nsrk gSA ;kuh childThread = new Thread(this, “ChildThread”);

bl Statement esa this Object MyFirstThread Class ds gh ,d Thread Object dk Reference gS vkSj ;s Method MyFirstThread Class ds run() Method dks gh Execute djrk gSA bl u, Run gksus okys Thread dk uke geus “ChildThread” j[kk gSA class MyFirstThread implements Runnable { Thread childThread; MyFirstThread() // No-Argument Constructor { childThread = new Thread(this, "ChildThread"); System.out.println("Child " + childThread); childThread.start(); // Start the Child Thread }

}

// This is the entry point of the second thread. public void run() { try { for(int i=0; i<5; i++) { System.out.println("Child Thread : " + i); Thread.sleep(1); } } catch(InterruptedException excp) { System.out.println("Child Thread Interrupted"); } System.out.println("Exiting Child Thread"); }

bl Thread esa geus ,d Constructor Create fd;k gS] rkfd ge tSls gh bl MyFirstThread Class dk dksbZ Hkh Object Create djsa] mldk uke “ChildThread” gks tk, vkSj og Thread Lo;a gh Run Hkh gks tk,A geus tks Constructor fy[kk gS] og fuEukuqlkj gS% Thread childThread; MyFirstThread() // No-Argument Constructor { childThread = new Thread(this, "ChildThread"); 378 Any Question or Suggestion, Just Discuss Here...

Java in Hindi }

System.out.println("Child " + childThread); childThread.start(); // Start the Child Thread

lcls igys geus Thread Super Class dk ,d Object childThread Create fd;k gSA pwafd bl Object dks geus dksbZ Memory Allocate ugha dh gS] blfy, ge blesa dsoy fdlh vU; Thread Object dk Reference gh Store dj ldrs gSaA fQj geus MyFirstThread dk ,d No-Argument Constructor Create fd;k gSA bl Constructor esa tkok Compiler dks Thread Class ds ,d 2-Argument Constructor ds igys Parameter }kjk ;s crk;k gS fd geus fdl Class esa Runnable Interface dks Implement fd;k gSA pwafd ge bl Constructor dks MyFirstThread Class ds vUnj gh Define dj jgs gSa] blfy, Thread Class ds 2-Argument Constructor esa igys Argument ds :i esa “this” Object dk iz;ksx djds geus tkok dks crk;k gS fd geus blh Class esa Runnable Interface dks Implement fd;k gS] ftlesa ge bl Constructor dks Define dj jgs gSaA lkFk gh nwljs Argument ds :i esa geus Create gksus okys u, Thread Object dk uke “ChildThread” fn;k gSA vc bl Create gksus okys Child Thread dks Run djus ds fy, Thread Class ds start() Method dks Thread Super Class ds Reference Object childThread Object ds fy, Call fd;k gSA

Stopping the Thread tc Thread dk run() Method vius vUr ij igqaprk gS] rHkh Thread Hkh vius vUr ij igqap tkrk gSA dbZ ckj tkok Lo;a gh fdlh Thread dks t:jr ds vuqlkj Stop dj nsrk gSA mnkgj.k ds fy, ekuyks fd ge ftl Applet dks Execute dj jgs gSa] mlesa ,d Applet gS vkSj ge fdlh nwljs Web Page ij pys tkrs gSa] ,sls esa Browser Lo;a gh Applet ds Thread dks Stop dj nsrk gSA fuEu mnkgj.k Program esa geus ,d Class esa ,d Thread dks Implement fd;k gS] lkFk gh mlds Main Program }kjk ;s Hkh n”kkZ;k gS fd ge fdl izdkj ls ,d lk/kkj.k ls Statement }kjk u;k Thread Object Create dj ldrs gSa% Program // File Name : ThreadApplication.java // Creating another Thread class MyFirstThread implements Runnable { Thread childThread; MyFirstThread() // No-Argument Constructor { childThread = new Thread(this, "ChildThread");


Java in Hindi System.out.println("Child " + childThread); }

}

childThread.start();

// Start the Child Thread

// This is the entry point of the second thread. public void run() { try { for(int i=0; i<5; i++) { System.out.println("Child Thread : " + i); Thread.sleep(1); } } catch(InterruptedException excp) { System.out.println("Child Thread Interrupted"); } System.out.println("Exiting Child Thread"); }

//------------------------------------------------------------------class ThreadApplication { public static void main(String args[]) { new MyFirstThread(); try {

}

}

for(int i=0; i<5; i++) { System.out.println("Main Thread : " + i); Thread.sleep(2); }

} catch(InterruptedException excp) { System.out.println("Main Thread Interrupted"); } System.out.println("Main Thread Exiting");


Java in Hindi Output Child Thread[ChildThread,5,main] Main Thread : 0 Child Thread : 0 Child Thread : 1 Main Thread : 1 Child Thread : 2 Main Thread : 2 Child Thread : 3 Main Thread : 3 Child Thread : 4 Exiting Child Thread Main Thread : 4 Main Thread Exiting

bl Program ds main() Method esa geus MyFirstThread Class dk ,d Object Create fd;k gSA pwafd main() Method tkok ds Run Time Virtual Machine esa Run gksrk gS] ysfdu fdlh Hkh vU; Thread dks Active djus dh {kerk main() Method esa gh gksrh gSA blfy, bl main() Method esa gh geus gekjh MyFirstThread Class ds Thread dks ,d Object ds :i esa Create fd;k gSA tc Program Run gksrk gS] rc lcls igys fuEu Statement }kjk ,d Object Create gksrk gS] tks fd MyFirstThread Class dk Object gksrk gSA new MyFirstThread();

pwafd MyFirstThread Class esa geus Runnable Interface dks Implement fd;k gS] blfy, ;s Class ,d Thread dh rjg dke djrk gS vkSj main() Method ds lekukUrj Execute gks ldrk gSA tc ;s Statement Execute gksrk gS] rc ;s Statement MyFirstThread Class ds NoArgument Constructor dks Execute djrk gSA bl Constructor esa ,d u;k Thread Create gksrk gS vkSj ml u, Thread dk Reference childThread uke ds Thread Class ds Reference Object esa Store gks tkrk gSA fQj bl Thread dks Run djus ds fy, blh Constructor esa Thread ds start() Method dks Use fd;k x;k gSA ;s Method Create gksus okys u, ChildThread ds run() Method dks Execute djds ml le; okil main() Thread esa vk tkrk gS] tc ,d Millisecond ds fy, Child Thread Sleeping Mode esa tkrk gSA fQj Main Thread Execute gksrk gS tgka try/catch Block esa ,d Loop ds vUnj ,d Message Print fd;k tkrk gSA tc Message Print gks tkrk gS] rc Main Method Hkh 2 Millisecond ds fy, Sleeping Mode esa tkrk gSA ftl le; Main Thread Sleeping Mode esa tkrk gS] ml le; tkok fQj ls Childe Thread ds Statements dk Execution “kq: dj nsrk gSA ;s Swapping dh Process rc rd pyrh jgrh gS] tc rd fd Child Thread dk End ugha gks tkrk gSA bl Program esa geus dsoy ,d gh Child Thread Create fd;k gSA ;fn ge pkgsa rks ,d ls T;knk Child Thread Create dj ldrs gSaA ,slk djus ds fy, gesa Application ds main() Method esa fuEukuqlkj Modification djuk gksrk gS% 381 Any Question or Suggestion, Just Discuss Here...

Java in Hindi Program class ThreadApplication { public static void main(String args[]) { new MyFirstThread(); new MyFirstThread(); try{

}

}

for(int i=0; i<5; i++){ System.out.println("Main Thread : " + i); Thread.sleep(2); }

} catch(InterruptedException excp) { System.out.println("Main Thread Interrupted"); } System.out.println("Main Thread Exiting");

Output Child Thread[ChildThread,5,main] Child Thread[ChildThread,5,main] Main Thread : 0 Child Thread : 0 Child Thread : 0 Child Thread : 1 Main Thread : 1 Child Thread : 2 Child Thread : 1 Main Thread : 2 Child Thread : 3 Child Thread : 2 Child Thread : 4 Main Thread : 3 Exiting Child Thread Main Thread : 4 Child Thread : 3 Child Thread : 4 Main Thread Exiting Exiting Child Thread

bl Program esa geus nks Child Thread Create fd, gSa vkSj izkIr gksus okys Output esa nks Child Threads o ,d Main Thread ;kuh dqy rhu Threads Execute gks jgs gSa vkSj rhuksa Threads vkil esa le;≤ ij Swapping Hkh dj jgs gSa] ftlls rhuksa Threads yxHkx ,d


Java in Hindi lkFk vius vUr ij igqaprs gSaA pfy,] ,d vkSj mnkgj.k }kjk Runnable Interface dks Implement djds Thread Create djuk o ml Thread dks Use djuk lh[krs gSaA Program class NewThread implements Runnable { public void run() {

}

}

// Step 1 // Step 2

for(int i=0; i<6; i++) { System.out.println(“\t NewThread : “ + i ); } System.out.println(“End of NewThread”);

class ImplementedThreadTesting { public static void main(String args[]) { NewThread newThreadObject = new NewThread(); Thread runnableNewThread = new Thread(newThreadObject);

}

}

runnableNewThread.start(); System.out.println(“End of Main Thread”);

//Step 3 //Step 4

Output End of Main Thread NewThread : 0 NewThread : 1 NewThread : 2 NewThread : 3 NewThread : 4 NewThread : 5 End of NewThread

bl mnkgj.k ds Output esa ge ns[k ldrs gSa fd main() Method okyk Main Thread Program ds “kq: gksrs gh End ij igqap jgk gS] fQj Hkh tks Child Thread gS] ftls Main() Thread Execute dj jgk gS] Main Thread ds End gksus ds ckn Hkh Execute gksrk gS vkSj vius vUr ij igqaprk gSA Output dk igyk Statement “End of Main Thread” lcls igys Execute gks jgk gS] tcfd ;s Statement main() Method dk vfUre Statement gSA bl Statement ds Execute gksus dk eryc ;s gS fd blls igys ds lHkh Statements Execute gks pqds gSa] tcfd ge Output esa ns[k ldrs gSa fd bl Statements ls igys ds


Java in Hindi Statements ckn esa Execute gks jgs gSaA pfy,] bl Program ds Run gksus dh Process dks le>us dh dksf”k”k djrs gSaA Program tSls gh Run gksrk gS] tkok dk Virtual Machine main() Method ds fy, ,d Main Thread miyC/k dj nsrk gS] ftlls main() Method tkok }kjk iznku fd, tkus okys Main() Thread esa Run gksus yxrk gSA fQj geus main() Method esa NewThread Class dk ,d Object newThreadObject Create fd;k gSA bl Thread Object dk iz;ksx tkok Compiler dks ;s crkus ds fy, fd;k tkrk gS] fd ge fdl Thread dks lekukUrj :i ls Run

djuk pkgrs gSaA

pwafd ge NewThread Class esa Define fd, x, run() Method ds Statements dks lekukUrj :i ls Run djuk pkgrs gSa] blfy, geus fuEu Statement }kjk NewThread Class dk Object newThreadObject Create fd;k gSA NewThread newThreadObject = new NewThread();

tkok dks ;s crkus ds fy, fd geus tks newThreadObject Create fd;k gS] og ,d Thread gS vkSj ge bls Current Thread ;kuh Main Thread esa Main Thread ds lekukUrj Run djuk pkgrs gSa] Thread Class dk ,d Object Create fd;k gS vkSj bl Thread Class Object ds Constructor esa Run fd, tkus okys u, Thread ds Object newThreadObject dks Argument ds :i esa Pass fd;k gSA ,slk djus ij tkok dk Compiler le> tkrk gS fd ge Current Thread ;kuh Main Thread esa ,d vkSj Sub Thread Run djuk pkgrs gSa vkSj ge ftl Thread dks Run djuk pkgrs gSa] og Thread NewThread Class ds :i esa Described gS] D;ksafd ge vxys Statement esa blh NewThread Class ds ,d Object newThreadObject dks Argument ds :i esa Thread Super Class ds Constructor esa Pass dj jgs gSaA Thread runnableNewThread = new Thread(newThreadObject);

tc ge Thread Class dk ,d Object Create djds mlesa Run fd, tkus okys Thread dh Class dk ,d Object Reference ds :i esa Pass dj nsrs gSa] rc tkok ds Thread Super Class ds Object esa Run fd, tkus okys Thread dk Reference Store gks tkrk gSA vc bl Thread Object esa ftl Thread dk Reference gksrk gS] ml Thread ds run() Method dks Execute djus ds fy, gesa Thread Class ds start() Method dks Execute djuk gksrk gSA ;s dke fuEu Statement }kjk djrs gSa% runnableNewThread.start();

pwafd runnableNewThread Thread Object esa blls fiNys Statement ds Execution ds dkj.k NewThread Class ds Object dk Reference Store gks tkrk gS] blfy, bl Statement ds Execution ls blh NewThread Class ds run() Method dk Execution “kq: gksrk gSA tc ;s Statement Execute gksrk gS] rc tkok Compiler NewThread Class ds run() Method ds Execution dks Start djds okil Main Thread esa vk tkrk gS vkSj Main Thread ds main() Method ds fuEu Statement dk Execution dj nsrk gS% System.out.println(“End of Main Thread”);


Java in Hindi pwafd ;s Statement main() Method dk vfUre Statement gksrk gS] blfy, bl Statement ds Execution ds ckn main() Method dk End gks tkrk gSA ysfdu ftl nwljs Sub Thread dks Main Thread esa main() Method }kjk Start fd;k x;k gS] og Thread vHkh End ij ugha igqapk gS] blfy, Main() Thread esa main() Method ds End gks tkus ds ckotwn NewThread ds run() Method dk Execution gksrk jgrk gS vkSj tc ml Child Thread ds run() Method dk End gksrk gS] rc Program iwjh rjg ls Terminate gksrk gSA mijksDr mnkgj.kksa dk lkjka”k ;s gS fd ge ftl Sub Program ;k Code Segment dks ,d Thread dh rjg lekukUrj :i ls Execute djuk pkgrs gSa] ml Sub Program ds Code Statements dks ,d ,slh Class esa Define djuk gksrk gS] ftlesa Runnable Interface dks Implement fd;k x;k gksrk gSA Runnable Interface dks Implement djus ij gesa blds run() Method dks ml Create dh tk jgh Class esa Implement djuk t:jh gksrk gSA Runnable Interface dk run() ,d ,slk Method gS] ftlesa fy[ks Statements lekukUrj :i ls Thread dh rjg Run gksrs gSa] blfy, gesa gekjs Sub Program ds lHkh Code Statements dks run() Method esa gh Define djuk gksrk gSA bruk dj nsus ij gekjs Thread dk Description rS;kj gks tkrk gSA

vc gesa bl Thread dks Run djuk gksrk gSA fdlh Hkh Thread dks Run djus ds fy, geas Thread Super Class ds start() Method dks Use djuk gksrk gSA blfy, gesa tkok dks ;s crkuk iMrk gS fd ge fdl Thread dks Execute djuk pkgrs gSaA tkok dks ;s crkus ds fy, gesa Thread Super Class dk ,d Object Create djuk gksrk gS vkSj mlds Constructor esa gekjs u, Thread ds ,d Object dk Reference Argument ds :i esa nsuk gksrk gSA tc ge Thread Super Class ds Constructor esa fdlh nwljs User Defined Thread Class ds Object dk Reference nsrs gSa] rc Compiler Thread Super Class ds Object esa ml u, Thread ds Object dk Reference Store dj nsrk gSA vc tc ge bl Thread Super Class ds Object ds fy, start() Method dks Call djrs gSa] rc ;s Method gekjs Create fd, x, Thread ds run() Method dks Execute dj nsrk gS] D;ksafd Thread Super Class ds Object esa gekjs Thread Object dk Reference gksrk gSA bl rjg ls gekjk u;k Thread lekukUrj :i ls ml Thread esa Run gksus yxrk gS] ftlesa geus Thread dks Start fd;k gksrk gSA fdlh lk/kkj.k Class dh rjg gh ge fdlh Applet Class esa Hkh Runnable Interface dks Implement dj ldrs gSa vkSj ,d Applet esa ,d gh le; esa ,d ls T;knk dkeksa dks lekukUrj :i ls iwjk dj ldrs gSaA pwafd ,d Applet Create djus ds fy, gesa gesa”kk Applet Class dh Sub Class Create djuh gksrh gSA blfy, fdlh Applet Class esa ;fn gesa Runnable Interface dks Implement djuk gks] rks gesa fuEukuqlkj Syntax Use djuk gksrk gS% public class MyApplet extends Applet implements Runnable { public void run() { // Executable codes goes here. } }


Java in Hindi bl Applet esa tks dke gesa Applet esa djuk gksrk gS] mu dkeksa dks rks Applet ds Methods esa Implement djrs gSa] tcfd tks dke gesa Applet ds lekukUrj djus gksrs gSa] mu dkeksa dks Applet esa Implement fd, x, run() Method esa Implement djrs gSaA ekuyks fd ge pkgrs gSa fd Applet ij ,d Button gks ftl ij Click djus ij ,d Musical Sound Play gks] tcfd fcuk fdlh O;o/kku ds Applet ij ,d Counter Number Increment gks dj Run gksrk jgsA pwafd Counter dqN Milliseconds ds fy, :d dj Increment gksxk vkSj Applet fQj ls Repaint gksxk] blfy, bl Counting Process dks gesa Runnable Interface ds run() Method esa Implement djuk gksxk] tcfd Button ij Click djus ij Musical Sound ds Play gksus dks Applet ds ,d Button ls Associate djuk gksxkA fdlh Applet esa bl dke ds fy, run() Method dks ge fuEukuqlkj Implement dj ldrs gSa% Program import java.awt.*; import java.applet.*; public class MyApplet extends Applet implements Runnable { String displayStr; int count = 0; {

}

}

public void run() while (count < 1000) { ++count; displayStr = String.valueOf(count); repaint();

}

try { thread.sleep(200); } catch (InterruptedException e) {}

public void paint(Graphics g) { g.drawString(displayStr, 100, 50); }

bl run() Method esa displayStr ,d String Object gS vkSj count uke dk ,d Integer izdkj dk Variable gSA run() Method esa geus ,d while Loop dks 1000 ckj Run fd;k gS vkSj bl Loop esa count uke ds Integer izdkj ds Variable dks Increment fd;k gSA fQj


Java in Hindi count Variable ds Integer izdkj ds eku dks String Object esa Convert djds displayStr uke ds String Object esa Store fd;k gSA fQj repaint() Method dks Call fd;k gSA repaint() Method Call djus ij Applet Class dk paint() Method Execute gksrk gS] tks displayStr String Object esa Stored Counter ds eku dks Applet ij Display dj nsrk gSA

pwafd ;s Statement ,d while Loop esa fy[kk x;k gS] blfy, displayStr esa 1000 ckj eku Change gksrk gS vkSj 1000 ckj paint() Method Call gksdj Counter dks Applet ij Display djrk gSA ysfdu while Loop ds gj Iteration esa Thread ds sleep() Method dk Execution gksrk gS vkSj gj Iteration 200 Millisecond :d dj Execute gksrk gSA gkykafd Applet ds vUnj geus Runnable Interface dks Implement djds ,d Thread rks Create dj fy;k gS] ysfdu ;s Thread rc rd Run ugha gksrk gS] tc rd Thread Super Class ds start() Method dks Call djds bl Thread ds fdlh Object dk Reference ugha fn;k tkrk gSA pwafd fdlh Hkh Thread dks Run djus ds fy, gesa lcls igys Thread Super Class dk ,d Object Create djuk gksrk gS vkSj fQj ml Thread Object ds Constructor esa Argument ds :i esa ml Thread dh Class dk Reference nsuk gksrk gS] ftlesa Runnable Interface dks Implement fd;k x;k gSA pwafd geus Runnable Interface dks Applet Class esa gh Implement fd;k gS] blfy, Thread Super Class Object ds Constructor esa Argument ds :i esa ge this Object Pass dj ldrs gSaA pwafd geus Runnable Interface dks Applet Class esa gh Implement fd;k gS] blfy, this Object Applet Class dks gh Refer djsxkA ge pkgrs gSa fd Applet ds Memory esa Load gks dj Start gksrs gh Thread Hkh Start gks tk,] blfy, gesa Applet Class ds start() Method dks Override djuk gksxk vkSj blh Method esa Thread Super Class ds Constructor esa Applet ds this Object dks Pass djds vius Thread dks Start djuk gksxkA pwafd tc ge Thread Super Class ds Object esa Applet dks Refer djus okys this Object dk gh Reference nsaxs] rks gekjs Applet ds Thread dk Reference Thread Super Class ds Object esa Store gks tk,xkA blfy, ge Thread Super Class ds start() Method dks Thread Super Class ds Object ds fy, gh Invoke djds Applet ds Thread dks Start dj ldrs gSaA ;kuh gesa Applet ds start() Method dks fuEukuqlkj Override djuk gksxk% Thread thread; {

}

public void start() count = 0; displayStr = ""; thread = new Thread(this); thread.start();


Java in Hindi ge tc Applet dks Stop djrs gSa] rHkh gekjk Thread Hkh Terminate gks tkuk pkfg,A blfy, Thread dks Store djus ls lEcaf/kr Code Statements dks gesa Thread ds stop() Method dks Override djds fuEukuqlkj fy[kuk gksrk gS% public void stop() { thread.stop(); }

bl Method dks Override djds Thread dks Stop djuk blfy, t:jh gS] D;ksafd Thread esa ,d Loop 1000 ckj Execute gksrk gS vkSj gj Iteration esa 200 Milliseconds dk le; ysrk gSA vc ;fn ge Applet ds Thread ds Loop ds Iterations iwjk gksus ls igys Applet dks Close djuk pkgsa] rks gesa Threads dks chp esa gh jksduk t:jh gksrk gSA ;fn ge ,slk uk djsa] rks Applet Terminate gksus ds ckn Hkh Applet dk Thread Execute gksrk jgsxk vkSj tc Thread ds run() Method dk Termination gksxk] rHkh Thread Terminate gksxkA ,slk gksus ij CPU csotg oks dke djus esa Busy jgsxk] ftldh t:jr gh ugha gSA bl rjg ls bl iwjs Applet Program dks ge fuEukuqlkj ,d lkFk Define dj ldrs gSa% Program import java.awt.*; import java.applet.*; import java.net.*; public class SoundApplet extends Applet implements Runnable{ Button button; Thread threada; int count; String displayStr; public void init() { setLayout(null); button = new Button("Play Sound"); add(button); button.setVisible(true); button.setBounds(5,80,250,60); resize(260, 150);

}

Font font = new Font("TimesRoman", Font.BOLD, 50); setFont(font);

public void start(){ count = 0; displayStr = ""; thread = new Thread(this);


Java in Hindi }

thread.start();

public void stop(){ thread.stop(); } public void run(){ while (count < 1000){ ++count; displayStr = String.valueOf(count); repaint();

}

}

try{ thread.sleep(200); }catch (InterruptedException e) {}

public void paint(Graphics g){ g.drawString(displayStr, 100, 50); }

}

public boolean action(Event evt, Object arg){ if (evt.target instanceof Button){ play(getCodeBase(), "spacemusic.au"); repaint(); } return true; }

Deriving a Class From Thread Thread Create djus dk nwljk rjhdk ;s gS fd ge Thread Class dks Derive djsaA mlds ckn Applet Class ;k fdlh Application Class esa ml Extended Thread Class dk ,d Object Create djsa vkSj ml Thread dks Run djus ds fy, mlds fy, start() Method Call djsaA Applet Class esa Thread Object dks Applet ds Data o Methods dks Access djus dh lqfo/kk nsus ds dkj.k ,d Applet o ,d Thread vkil esa vklkuh ls Communication dj ikrs gSa] ftlls Applet o Thread nksuksa gh lekukUrj :i ls Run gks ikrs gSaA ge gekjh Class dks java.lang.Thread Class ls Extend djds ,d Runnable Thread dh rjg Define dj ldrs gSaA tc ge Thread Class dks gh Extend djds ,d ubZ Thread Class cukuk pkgrs gSa] rc ,slk djus ds fy, gesa fuEu Steps Follow djus gksrs gSa% ubZ Thread Class dks java.lang.Thread Class ls Extend djsaA 2 Thread Class ds run() Method dks Implement djsa] tks fd fdlh Hkh Thread ds Executable Codes dks Execute djus ds fy, ftEesnkj gksrk gSA 1


Java in Hindi 3 vc bl Extended Class dk ,d Thread Object Create djsa vkSj blds fy, start() Method dks Call djds Thread dks Start djsaA pfy,] bu Steps dks FkksMk vkSj le>rs gSsa% Declaring the Class ,d u, Thread dks Create djus ds fy, ge Thread Class dks fuEukuqlkj Extend dj ldrs gSa% class MyThread extends Thread { // Thread Codes goes here. ... // run() Method Implementation code goes here. }

bl izdkj Thread dks Extend djus ij gekjs ikl MyThread uke dk ,d vkSj Thread Class gksrk gS] ftlds Objects Create fd, tk ldrs gSaA

Implementing the run() Method tc Thread Class dks Extend djrs gSa] rc bldk run() Method Hkh Inherit gks tkrk gSA gesa bl Method dks Override djuk gksrk gS vkSj bl Method esa os Codes fy[kus gksrs gSa] tks Thread ds Execution ds lkFk gh Execute gksus pkfg,aA run() Method dk Basic Implementation gesa fuEukuqlkj fn[kkbZ nsrk gS% class MyThread extends Thread { // Thread Codes goes here. ...

}

run() { // Implementation code goes here. }

pwafd] tc tkok fdlh u, Thread dks Start djrk gS] rks og ml Thread ds blh run() Method dks Call djrk gS] blfy, fdlh Thread }kjk gesa tks Hkh dke djokus gksrs gSa] mUgsa blh Method esa Define djrs gSaA

Starting New Thread fdlh Thread dks Run djus ds fy, gesa ml Thread dks Extend djus ds ckn ml Thread dk Object Create djuk gksrk gS vkSj ml Object ds fy, start() Method dks Call djuk


Java in Hindi gksrk gSA mnkgj.k ds fy, ekuyks fd gesa MyThread Class dk Object Create djds mls Run djuk gSA blds fy, gesa fuEukuqlkj Code fy[kuk gksrk gS% MyThread myNewThread = new MyThread(); myNewThread.start();

bl Code dh igyh Line MyThread Class dk ,d Object Create djrk gSA tks Thread bl Object dks Run djsxk og Object vHkh Run ugha gks jgk gSA ;kuh ;s Thread vHkh Newborn State esa gSA bl Code Segment dh nwljh Line esa Thread Object ds lkFk start() Method dks Call fd;k x;k gSA start() Method myNewThread Object dks Runnable State esa ys tkrk gS] ftlesa Thread dk run() Method Execute gksus yxrk gS vkSj Thread Runnable State esa vk tkrk gSA start() Method ,d ,slk Method gS tks fdlh Main Thread esa Run fd, tkus okys fdlh nwljs Thread ds run() Method dks Invoke djds rqjUr fQj ls Main Method esa vk tkrk gS vkSj Main Method ds vxys Statement dk Execution dj nsrk gSA bl izfØ;k dks ge

fuEukuqlkj ,d mnkgj.k }kjk le> ldrs gSa%

Program // File Name : ExtededThreadUsingApplication.java class FirstThread extends Thread { public void run() { for(int i=0; i<5; i++) { try { System.out.println("In FirstThread i = : " + i); Thread.sleep(1); } catch(InterruptedException e) { System.out.println("Another Thread Interrupted"); } } System.out.println("Exiting from FirstThread \n"); } } class SecondThread extends Thread { public void run() { for(int i=0; i<5; i++) { try { 391 Any Question or Suggestion, Just Discuss Here...

Java in Hindi System.out.println("In SecondThread i = : " + i); Thread.sleep(2);

} catch(InterruptedException e) { System.out.println("Another Thread Interrupted"); }

}

} System.out.println("Exiting from SecondThread \n"); }

class ThirdThread extends Thread { public void run() { for(int k=0; k<5; k++) { System.out.println("In ThirdThread k = : " + k); } System.out.println("Exiting from ThirdThread \n"); } } public class ExtededThreadUsingApplication { public static void main(String args[]) { new FirstThread().start(); new SecondThread().start(); new ThirdThread().start(); } } Output In FirstThread i = : 0 In SecondThread i = : 0 In ThirdThread k = : 0 In ThirdThread k = : 1 In ThirdThread k = : 2 In ThirdThread k = : 3 In ThirdThread k = : 4 Exiting from ThirdThread In FirstThread i = : 1 In SecondThread i = : 1 In FirstThread i = : 2 In SecondThread i = : 2 In FirstThread i = : 3


Java in Hindi In FirstThread i = : 4 In SecondThread i = : 3 Exiting from FirstThread In SecondThread i = : 4 Exiting from SecondThread

bl Program es geus Thread Class dks rhu Sub Classes esa Inherit fd;k gS vkSj rhuksa gh Classes esa Thread Class ds run() Method dks Implement djds mlesa Sub Program ds Codes fy[ks gSaA rhuksa gh Thread vkil esa Swap gks ldsa] blfy, rhuksa gh Threads esa sleep() Method dk iz;ksx djds Threads dks 1 Millisecond ds fy, Sleep Mode esa Hkstk gSA pwafd sleep() Method ml le; ,d Exception Throw djrk gS] tc dksbZ nwljk Thread igys Thread dks Interrupt djrk gSA blfy, sleep() Method dks gesa”kk ge try/catch Block esa fy[krs gSaA

Thread Exception

sleep() Method ,d Exception Throw djrk gSA ;fn ge bl Exception dks Catch uk djsa] rks gekjk Program Compile ugha gksrk gSA dksbZ Thread tc Suspend Mode esa gksrk gS] rc og fdlh Method dks Invoke djus dh fLFkfr esa ugha gksrk gSA ;fn ml le; ge ml Thread ls fdlh Method dks Invoke djokrs gSa] rks sleep() Method IllegalThreadStateException Throw djrk gSA

mnkgj.k ds fy, ;fn dksbZ Thread Sleep Mode esa gks rks og resume() Method dks Invoke ugha dj ldrk gSA D;ksafd dksbZ Sleeping Thread dksbZ Hkh Instruction Execute djus esa l{ke ugha gksrk gSA ;gh fLFkfr suspend() Method ds lEca/k esa Hkh gksrh gSA ;fn ge ,sls Method dks Call dj jgs gSa] tks Exception Throw dj ldrk gS] rks gesa mlds Exception dks Handle djuk t:jh gksrk gSA blds fy, gesa Appropriate Exception Handler fy[kuk gksrk gSA ,d Exception Handler ds catch Block dk fuEu esa ls dksbZ :i gks ldrk gS% catch(ThreadDeath excp ) { ... ... }

// Killed Thread

catch(InterruptedException excp ) { ... ... }

// Killed Thread

catch(IllegalArgumentException excp )


Java in Hindi { }

... ...

// Killed Thread

catch(Exception excp ) { ... ... }

// Killed Thread

Thread Scheduling – Setting Thread Priority

vki lksap ldrs gSa fd ,d gh Single CPU okys Computer System ij Multithreaded Programming dSls lEHko gks ikrh gSA D;ksafd ,d Computer System esa dsoy ,d gh CPU gksrk gS vkSj ,d CPU ,d le; esa dsoy ,d gh Computer Instruction dks Execute dj

ldrk gSA

bldk eryc ;s gqvk fd ge fdlh Program dks pkgs ftrus Sub Programs esa foHkkftr dj ysa] CPU ,d le; esa dsoy ,d gh dke djus esa l{ke gksxkA okLro esa ,d Simple CPU okyk Computer ,d le; esa dsoy ,d gh dke djrk gS] ysfdu Multithreading esa ,d gh Program ds fofHkUu Sub Programs ds ,d&,d Instruction dks CPU ij Process gksus ds fy, Hkstk tkrk gS] blfy, gesa ,slk yxrk gS] tSls lHkh Sub Programs lekukUrj :i ls Run gks jgs gSaA pfy,] le>us dh dksf”k”k djrs gSa fd ,d Single CPU okys Computer System ij Multithreading Programming dks fdl izdkj ls lEHko cuk;k tkrk gSA fdlh Single CPU okys System ij Parallel Thread Execution dks lEHko cukus ds fy, gj Thread dks ;s Opportunity iznku dh tkrh gS fd Regular Intervals ij fofHkUu Threads ds Codes esa ls FkksMk lk Code Execute gks tkrk gSA bl Approach dks Time-Slicing dgk tkrk gS] ftlesa gj Thread dks CPU dk FkksMk lk le; fey tkrk gSA pwafd ,d Single CPU Hkh ,d Second esa djksMksa Instructions dks Execute djus esa l{ke gksrk gS] blfy, ge tc ,d ,sls Program dks Run djrs gSa] ftlesa ,d Program fofHkUu Threads esa foHkkftr gksrk gS vkSj gj Thread ds Codes dk dqN fgLlk le;≤ ij ,d Regular Intervals ds ckn Execute gksrk jgrk gS] rks gesa ,slk yxrk gS] tSls ,d gh le; esa ,d lkFk dbZ dke Parallel Form esa Perform gks jgs gSaA fdlh Program ds fofHkUu Threads fdrus&fdrus le; ds fy, CPU dk Attention izkIr dj ldrs gSa] ;s r; djus dh izfØ;k dks Scheduling dgk tkrk gSA vHkh rd geus ftrus Hkh Programs cuk, gSa] muesa lHkh Threads dks yxHkx leku le; iznku fd;k x;k gS vkSj CPU gj Thread dks leku Attention nsrk gSA ysfdu ifjfLFkfr;ka ges”a kk ,slh ugha gksrh gSa] tgka lHkh Threads dks CPU ls leku le; izkIr gksA dbZ ckj ifjfLFkfr;ka ,slh gksrh gSa] ftlesa fdlh Thread dks CPU ds T;knk Attention dh t:jr gksrh gSA ,sls esa fofHkUu izdkj ds Threads dks vyx izdkj dh Priority iznku djuk


Java in Hindi gksrk gSA blfy, gj Multithreaded Programming Language esa Prioritization dk dksbZ uk dksbZ rjhdk t:j Develop fd;k x;k gksrk gS] rkfd fdlh Program ds fofHkUu Threads fofHkUu Priority Level ij Execute gks ldsaA tkok ,d ,sls Priority Scheduling System dks Employ djrk gS] ftls “Fixed Priority Scheduling” dgk tkrk gSA bl Scheduling esa Thread dk Execution vU; fofHkUu Threads ds “RELATIVE” Priority ij vk/kkfjr gksrk gSA bl Priority esa gj Thread dks ,d Relative Priority Level iznku fd;k tkrk gS] ftlesa fofHkUu Threads }kjk CPU ds Attention dks izkIr fd, tkus dk Øe r; gksrk gSA ;kuh ;s r; gksrk gS fd fdl Thread ds ckn fdl Thread dks CPU dk Time feysxkA ftu Threads dks High Priority izkIr gksrh gS] os Threads CPU dk Attention igys izkIr djrs gSa tcfd ftu Threads dks Low Priority iznku dh tkrh gS] os Threads CPU dk Attention rc izkIr djrs gSa] tc CPU Idle Mode esa gksrk gSA tkok ds Thread Scheduling Approach dh ,d lcls egRoiw.kZ ckr ;s gS fd tkok TimeSlicing Approach dks Use ugha djrk gSA nwljs “kCnksa esa dgsa rks Currently tks Thread Execute gks jgk gksrk gS] ml Thread ds ikl CPU dk iwjk Control rc rd jgrk gS tc rd fd ;s Thread viuk Control fdlh nwljs Thread dks Transfer ugha djrk gSA blfy, Lower Priority Threads Higher Priority Threads ls CPU ds Control dks fn, tkus dk bUrtkj djrs gSaA tc Higher Priority Threads Lower Priority Threads dks Control nsrs gSa] rc Lower Priority Threads ds Codes dk Execution gksrk gSA ftu Threads dk Priority Level leku gksrk gS] os Threads Øe ls ,d nwljs ds ckn Execute gksrs gSaA Java Runtime System esa fLFkr Garbage Collection Thread Low-Priority Thread dk ,d lcls vPNk mnkgj.k gSA gkykafd Garbage Collection ,d cgqr gh egRoiw.kZ dke gS] ysfdu bls CPU dk Attention Urgently izkIr djus dh dksbZ t:jr ugha gksrh gSA

D;ksafd bl Thread dk dke rc “kq: gksrk gS tc dksbZ Object viuk dke iwjk dj ysrk gS vkSj Destroy gksrk gSA ;s Thread Background esa bu Destroy gksus okys Objects ls Return gksus okyh Memory o Resources dks Collect djus dk dke djrk jgrk gSA pwafd bldk dke fdlh Hkh Program dk vfUre dke gksrk gS] blfy, bls tkok ds Runtime System esa lcls Low Priority iznku fd;k x;k gSA blh rjg ls User tks Input nsrk gS] ml Input dks Receive o Handle djus ds fy, tks Thread dke djrk gS] ml Thread dks Maximum Priority iznku fd;k tkrk gSA rkfd User ds Input dks rqjUr Respond fd;k tk ldsA

Establishing Thread Priority tc ,d u;k Thread create gksrk gS] rc og Thread viuh Priority ml Thread ls Inherit djrk gS] ftlls ;g Create gqvk gksrk gSA Thread Class rhu Constants Define djrk gS rks fofHkUu Threads ds Relative Priority Levels dks Represent djrk gSA ;s rhuksa Constants fuEukuqlkj gSa% MIN_PRIORITY


Java in Hindi NORM_PRIORITY MAX_PRIORITY

tkok ds Garbage Collection Thread dks MIN_PRIORITY iznku fd;k x;k gS] tcfd os Threads tks User ds Input dks Manage djrs gSa] mUgsa MAX_PRIORITY iznku fd;k x;k gSA lkekU;r;k gekjs fcuk fdlh izdkj dh Priority Set fd, gq, gh tks Threads Create gksrs gSa] mudh Priority Normal gh gksrh gSA ;fn ge fdlh Thread dks vyx ls Priority Set djuk pkgsa] rks bl dke ds fy, ge setPriority() Method dks Use djds fdlh Hkh Thread dks vyx izdkj dh Priority iznku dj ldrs gSaA tkok ds ;s Thread Priority Constants Integers gksrs gSa tks MIN_PRIORITY ls MAX_PRIORITY rd dh Range dks r; djrs gSaA tcfd NORM_PRIORITY bu nksuksa ds chp dk eku gksrk gSA MIN_PRIORITY dk eku 1 gksrk gS tcfd MAX_PRIORITY dk eku 10 gksrk gSA bl fLFkfr esa NORM_PRIORITY dk eku 5 gksrk gSA blhfy, tc Hkh dksbZ Thread Create gksrk gS] mldh Priority dk Level 5 gksrk gS] D;ksafd gj u;k Create gksus okyk Thread ,d Normal Priority okyk Tread gksrk gSA ;fn ge bl Range ls ckgj dh Priority Set djrs gSa] rks tkok ,d IllegalArgumentException uke dk Exception Throw djrk gSA lkekU;r;k ;fn ge fdlh Thread dks fdlh nwljs Normal Priority okys Thread ls vf/kd Priority nsuk pkgrs gSa] rks gesa Normal Priority ls 1 vf/kd Priority Set djuk gksrk gS tcfd ;fn ge fdlh Thread dks vU; Thread dh rqyuk esa de Priority nsuk pkgrs gSa] rks gesa Normal Priority ls ,d de Priority Set djuk gksrk gSA gkykafd ge fdlh Thread dks Minimum Priority nsus ds fy, 1 o Maximum Priority nsus ds fy, 10 dk iz;ksx dj ldrs gSa ysfdu fQj Hkh gesa ,slk ugha djuk pkfg,A gesa buds fy, Øe”k% Priority Level NORM_PRIORITY – 1 = 4 o Priority Level NORM_PRIORITY + 1 = 6 dk iz;ksx gh djuk pkfg,A fdlh Thread dks Priority Set djus ds fy, ge fuEukuqlkj Statement dk iz;ksx dj ldrs gSa% myThread.setPriority(Thread.MAX_PRIORITY);

blh rjg ls ;fn ge fdlh Thread dh Priority Level izkIr djuk pkgrs gSa] rks gesa getPriority() Method dks fuEukuqlkj Use djuk gksrk gS% int priority = myThread.getPriority();

fdlh Thread dh Priority dks izkIr djds ge ml Thread ds Priority Level Constant dks Increment ;k Decrement djds ml Thread dh Priority dks vU; Threads dh rqyuk esa de ;k T;knk ij Set dj ldrs gSaA ;s dke djus ds fy, ge fuEukuqlkj Syntax dk iz;ksx dj ldrs gSa% myThread.setPriority(myThread.getPriority() + 1 );


Java in Hindi pwafd ge tkurs gSa fd fdlh Hkh Thread dh Normal Priority dk eku 5 gksrk gS] blfy, ;fn ge fdlh Thread dh Normal Priority esa ,d Add dj nsa] rks og Thread vU; Threads dh rqyuk esa High Priority okyk Thread cu tkrk gSA fiNys Statement esa geus ;gh dke fd;k gSA ;kuh Thread dks Normal Priority okys Thread ls High Priority okys Thread esa Convert fd;k gSA fdlh Thread dks Priority iznku djds ge ;s r; djrs gSa fd og Thread CPU dk Attention izkIr djus ds fy, T;knk Able gS ;k deA mnkgj.k ds fy, gesa fdlh Input dks ftruk gks lds mruk Quick rjhds ls Response djuk gksrk gSA blfy, Input ls lEcaf/kr Thread dks gesa vU; Threads dh rqyuk esa vf/kd Priority iznku djuk t:jh gksrk gSA tc dHkh Hkh tkok esa ,d ls T;knk Threads Execution ds fy, CPU dk Attention izkIr djus ds fy, rS;kj gksrs gSa] rc tkok Threads ds Queue esa ls Highest Priority okys Thread dks pqurk gS vkSj mls CPU ij Process gksus ds fy, Hkst nsrk gSA bl fLFkfr esa ,d Lower Priority okyk Thread rc CPU dk Attention izkIr djrk gS] tc fuEu esa ls dksbZ ifjfLFkfr gksrh gS% 1 2 3 4

tc tc tc tc gSA

Highest Priority Highest Priority Highest Priority Highest Priority

okys Thread okys Thread okys Thread okys Thread

ds run() Method dk End gks tkrk gSA esa sleep() Method dk iz;ksx fd;k x;k gksrk gSA esa wait() Method dk iz;ksx fd;k x;k gksrk gSA esa suspend () Method dk iz;ksx fd;k x;k gksrk

Currently Running High Priority Thread ds Just ckn esa Execute gksus okyk Thread ;fn High Priority Thread ugha gS] rks Currently Thread }kjk ml Thread dks rc rd ds fy, jksd fn;k tkrk gS] tc rd Currently Running Thread iwjk ugha gks tkrk gSA ,d ckr /;ku j[ksa fd Highest Priority okyk Thread gesa”kk Low Priority okys Thread dks Execute gksus

ls jksdrk gSA

Program // File Name : ThreadPriority2.java class NewThread extends Thread { public void run() { System.out.println("New Thread Started"); for(int i=0; i<5; i++) { System.out.println("\t From NewThread i =" + i); } System.out.println("Exit From NewThread"); } } class OldThread extends Thread { public void run()


Java in Hindi {

}

}

System.out.println("Old Thread Started"); for(int i=0; i<5; i++) { System.out.println("\t From OldThread i =" + i); } System.out.println("Exit From OldThread");

class MidThread extends Thread { public void run() { System.out.println("Mid Thread Started"); for(int i=0; i<5; i++) { System.out.println("\t From MidThread i =" + i); } System.out.println("Exit From MidThread"); } } public class ThreadPriority2 { public static void main(String args[]) { NewThread newThread = new NewThread(); OldThread oldThread = new OldThread(); MidThread midThread = new MidThread(); newThread.setPriority(Thread.MAX_PRIORITY); midThread.setPriority(midThread.getPriority() + 1); oldThread.setPriority(Thread.MIN_PRIORITY); System.out.println("New Thread Started"); newThread.start(); System.out.println("Old Thread Started"); oldThread.start(); System.out.println("Mid Thread Started"); midThread.start();

}

}

System.out.println("End of the Main Thread");

Output


Java in Hindi New Thread Started New Thread Started From NewThread i =0 From NewThread i =1 From NewThread i =2 From NewThread i =3 From NewThread i =4 Exit From NewThread Old Thread Started Mid Thread Started Mid Thread Started From MidThread i =0 From MidThread i =1 From MidThread i =2 From MidThread i =3 From MidThread i =4 Exit From MidThread End of the Main Thread Old Thread Started From OldThread i =0 From OldThread i =1 From OldThread i =2 From OldThread i =3 From OldThread i =4 Exit From OldThread

bl Program esa geus newThread Thread Object dks lcls T;knk Priority nh gS] blfy, Output esa ge ns[k ldrs gSa] fd ;s Thread lcls igys Execute gks jgk gS] tcfd oldThread Thread Object dks geus lcls de Priority nh gS] blfy, ;s Thread lcls ckn esa Execute gks jgk gSA ;gka rd fd Main Thread dk End gksus ds ckn ;s Thread Execute gksuk “kq: gksrk gSA

Daemons

vHkh rd geus ftu Threads ds ckjs esa tkudkjh izkIr dh gS os lHkh Threads fdlh uk fdlh Parent Thread ds vUnj Run gksrs gSaA tkok gesa ,d vU; izdkj ds Threads Create djus dh lqfo/kk Hkh iznku djrk gS] ftls Daemon Thread dgk tkrk gS vkSj ;s Threads yxHkx mlh rjg ls dke djrs gSa] ftl rjg ls dksbZ Independent Process dke djrk gSA Traditional Threads dh rjg Daemon Threads Lo;a Run Time System ls Belong gksrs gSa uk fd fdlh Particular Program lsA Garbage Collection Thread ,d Perfect Daemon Thread dk mnkgj.k gSA ;s fdlh Hkh vU; Program ls Lora= :i ls Run gksrk gS vkSj ,slk dke djrk gS] ftldk Qk;nk lHkh vU; Programs dks feyrk gSA

bl izdkj ds Threads Create djds okLro esa ge tkok ds Run Time System dks Modify djrs gSa] ftldk Qk;nk lHkh vU; Programs dks feyrk gSA ge fdlh Thread dks setDaemon() Method dks Call djds Daemon Thread esa Convert dj ldrs gSaA bl 399 Any Question or Suggestion, Just Discuss Here...

Java in Hindi Method dks Hkh Thread Class esa Define fd;k x;k gSA fdlh Thread dks Daemon Thread cukus ds fy, gesa setDaemon() Method esa True Pass djuk gksrk gSA ;kuh myThread.setDaemon(true);

dksbZ Thread Daemon Thread gS ;k ugha bldk irk yxkus ds fy, ge Thread Class esa Define fd, x, isDaemon() Method dks fuEukuqlkj Use dj ldrs gSa% boolean thisIsDaemonThread = myThread.isDaemon(); Java Runtime blds lHkh Threads ds Execution ds Finish gksus ds ckn Hkh miyC/k jgrk gSA fQj Hkh tc ;s fdlh Daemon Thread ij igqaprk gS] rc ,d Exception Generate djrk gSA D;ksafd Daemon Threads dqN fo”ks’k izdkj ds dke djus ds fy, Design fd, tkrs gSaA blfy, tkok bUgsa rc Hkh Run djrk jgrk gS] tc tkok Runtime ds lHkh Threads dk Execution lekIr gks pqdk gksrk gSA

The ThreadGroup

bl Class dk iz;ksx Threads ds ,d iwjs Group dks ,d Single Unit dh rjg Use djus ds fy, fd;k tkrk gSA ;s Class gesa Threads ds ,d lewg ds fofHkUu Threads ds Execution dh Series dks Control djus dk ,d rjhdk iznku djrk gSA mnkgj.k ds fy, ThreadGroup Class fdlh Threads ds iwjs ,d Group dks Control djus ds fy, gesa stop(), suspend() vkSj resume() Methods Provide djrk gSA ,d ThreadGroup esa dksbZ nwljk ThreadGroup Hkh gks ldrk gSA ;kuh ,d ThreadGroup esa ge vU; ThreadGroup dh Nesting Hkh dj ldrs gSaA ,d Individual Thread ds ikl mlds Immediate ThreadGroup dks Access djus dh Ability gksrh gS] ysfdu og Thread vius Parent ThreadGroup dks Access ugha dj ldrk gSA Threads dh Grouping djuk blfy, egRoiw.kZ gksrk gS D;ksafd ;s gesa dbZ ckj ,d Single Entity ds :i esa ,d ls T;knk Threads dks Handle djus dh lqfo/kk nsrk gSA mnkgj.k ds fy, ThreadGroup Class esa suspend() o resume() tSls Methods gksrs gSa] ftudk iz;ksx fdlh ThreadGroup ds lHkh Threads dks Suspend ;k Resume djus ds fy, fd;k tk ldrk

gSA

tkok esa ftrus Hkh Threads Create fd, tkrs gSa] os lHkh Threads fdlh uk fdlh Group ls lEcaf/kr gksrs gSaA vHkh rd geus ftrus Hkh Program ns[ks gSa] muesa fdlh Hkh Program esa geus fdlh Thread dks fdlh Hkh Group ls Associate ugha fd;k gSA tc ge fdlh Thread dks fdlh Hkh Group ls Associate ugha djrs gSa] rks ge ftl Thread esa fdlh Thread dks Create djrs gSa] mlh Current Thread ftl Group dk gksrk gS] mlh Group esa gekjk u;k Thread Add gks tkrk gSA Current Thread og Thread gksrk gS] tgka gekjk u;k Thread Create gksrk gSA dqN ifjfLFkfr;ksa esa ,slk Hkh lEHko gksrk gS fd tgka u;k Thread Create gks jgk gS] ogka dksbZ Current Thread uk gksA tc ,slh ifjfLFkfr gksrh gS rc tkok dk Runtime System Create


Java in Hindi gksus okys Thread dks mlds Default Thread Group esa Add dj nsrk gSA bl Default Thread Group dk uke Main gksrk gSA Thread Create djds ge ml Thread dks fdlh Appropriate Group ls Associate dj ldrs gSaA ge fdlh Hkh Thread dks dsoy ,d ckj gh fdlh Group esa Add dj ldrs gSaA ;fn geus fdlh Thread dks fdlh Group esa Add dj fn;k gS rks ge ml Thread ds Group dks fdlh Hkh rjg ls Change ugha dj ldrs gSaA

fdlh Thread dks fdl Thread Group esa Add djuk gS] blds fy, Thread Class gesa fuEukuqlkj rhu Constructors Provide djrk gS] ftudk iz;ksx djds ge fdlh Thread dks fdlh veqd Group esa Add dj ldrs gSaA ;s Constructors fuEukuqlkj gSa% Thread(ThreadGroup, String) Thread(ThreadGroup, Runnable) Thread(ThreadGroup, Runnable, String)

bu rhuksa Constructor esa igys Argument ds :i esa gesa ,d ThreadGroup izdkj dk Object Pass djuk gksrk gSA igyk Constructor ,d String Parameter Hkh ysrk gS] tks fd Thread ds uke dks Represent djus ds fy, Use fd;k tkrk gSA vxys nks Constructors esa nwljs Argument ds :i esa gesa ,d Runnable Object dk Reference nsuk gksrk gS] tks fd ml Class dk Object gksrk gS] ftlesa Runnable Interface dks Implement fd;k x;k gSA rhljs Constructor esa rhljs Argument ds :i esa ge ThreadGroup esa Add fd, tk jgs Runnable Object dk uke ns ldrs gSaA blls igys fd ge dksbZ Thread Create djsa] gesa ThreadGroup Class dk ,d Object Create djuk gksrk gSA ThreadGroup Class esa nks Constructor Define fd, x, gSa tks fuEukuqlkj gksrs gSa% ThreadGroup(String name) ThreadGroup(ThreadGroup parent, String name)

igyk Constructor Specify fd, x, uke dk ,d Empty ThreadGroup Object Create djrk gSA nwljk Constructor Hkh ;gh dke djrk gS] ysfdu Create gksus okys u, ThreadGroup dks Specify fd, x, parent ThreadGroup esa Place djrk gSA ;s Constructor gesa ,d ThreadGroup esa nwljk ThreadGroup Nest djus dh lqfo/kk nsrk gSA ge fuEukuqlkj ,d ThreadGroup Create djds mlesa u, ThreadGroup dks Nest dj ldrs gSa% ThreadGroup group = new ThreadGroup(“Parent Thread”); Thread t1 = new Thread(group, "Child Thread 1"); Thread t2 = new Thread(group, " Child Thread 2"); t1.start(); t2.start(); ... group.sleep(100); ...


Java in Hindi group.suspend(); ... group.resume(); ThreadGroup Create gksus ds ckn ge gj Thread dks Create djds bl ThreadGroup Object esa Pass dj ldrs gSaA ,slk djus ij fofHkUu Threads ThreadGroup ds Member cu tkrs gSaA fQj gj Thread dks muds start() Method dks Call djds Start fd;k tkrk gSA ThreadGroup Object esa Stored lHkh Threads dks ge ,d lkFk Start ugha dj ldrs gSaA ysfdu fdlh ThreadGroup ds fofHkUu Threads dks ge ,d lkFk Sleep Mode esa ;k Suspend Mode esa Hkst ldrs gSa vkSj lHkh Threads dks ,d lkFk Resume dj ldrs gSaA

dksbZ Thread fdl ThreadGroup dk lnL; gS] ;s tkuus ds fy, ge getThreadGroup() Method dk iz;ksx dj ldrs gSaA ;s Method ml ThreadGroup Object dks Return djrk gS] ftlls dksbZ Thread Belong djrk gSA fQj ge getName() Method dk iz;ksx djds mlds ThreadGroup Object dk uke izkIr dj ldrs gSaA fuEu Code Segment crkrk gS fd ge fdl izdkj ls fdlh ThreadGroup dk uke Print dj ldrs gSa% ThreadGroup group = myThread.getThreadGroup(); System.out.println(group.getName());

Thread States – The Life Cycle of a Thread

geus fiNys nks mnkgj.kksa esa ;s le>k fd fdl izdkj ls fdlh Sub Program dks ,d Thread ds :i esa Convert djds lekukUrj :i ls Execute fd;k tk ldrk gS] ysfdu vHkh rd geus ;s ugha tkuk gS fd fofHkUu Threads Java-Thread-States esa fdl izdkj ls Run gksrs gSaA ge tks Hkh Thread Create djds Thread Object ds :i esa Represent djrs gSa] os lHkh Threads viuh Life-Cycle esa ,d fuf”pr Thread States esa Travers djrs gSaA dksbZ Hkh tkok Thread eq[r;k ikap Thread States esa Traverse djrk gSA os fLFkfr;ka fuEukuqlkj gSa% 1 2 3 4 5

NEWBORN State RUNNABLE State RUNNING State BLOCKED State DEAD State


Java in Hindi NEWBORN State tc ge lcls igys ,d u;k Thread Object Create djrs gSa] rc Create gksus okys Thread dks NEWBORN State dk Thread dgk tkrk gS] D;ksafd bl Thread dks Run gksus ds fy, vHkh rd Schedule ugha fd;k x;k gksrk gSA dksbZ u;k Thread Object Create djus ds fy, ge fuEukuqlkj Code Statement fy[krs gSa% Thread newThreadObject = new Thread(this);

bl Statement esa this Object crkrk gS fd Thread dks Run djus ds fy, run() Method dks Current Object ds fy, Call djuk gksxk vkSj ;fn ge bl Thread dks Terminate djuk pkgrs gSa] rks Thread dks Terminate djus ds fy, stop() Method dks Hkh gesa blh Object ds fy, Call djuk gksxkA ;kuh gesa Thread ds lkFk ftl fdlh Hkh izdkj dk Hkh dke djuk gS] ml dke dks Perform djus okys Method dks blh Object ds lkFk Call djuk gksxkA tc ge lcls igys dksbZ u;k Thread Object Create djrs gSa] rc ge bl Object ds lkFk fuEu esa ls gh dksbZ Method Call dj ldrs gSa% 1

2

start() Method dk iz;ksx djds bls Run djus ds fy, Schedule dj ldrs gSaA stop() Method dk iz;ksx djds Thread dks Terminate dj ldrs gSaA

;fn ge Thread dks Schedule djrs gSsa] rks Thread RUNNABLE State esa Move gks tkrk gSA ;fn Thread Create djus ds ckn ml Thread Object ds lkFk start() ;k stop() Method ds vykok dksbZ vU; Method Call djrs gSa] rks bl Stage esa ,d Exception Throw fd;k tkrk gSA fiNyk Code Statement ,d Thread Object Create djrk gS] ysfdu vHkh rd bl Thread Object dks fdlh izdkj dk dksbZ Resource Allocate ugha fd;k x;k gSA vHkh rd ;s ,d Empty Object gksrk gSA blfy, bl Thread dks Start djus ds fy, gesa start() Method dks Call djuk gksrk gSA ;s dke ge fuEukuqlkj Statement }kjk djrs gSa% newThreadObject.start();

;fn ge Thread dks Start djuk uk pkgsa] rks ;gha ij stop() Method dks Call djds Thread dks fuEukuqlkj Terminate Hkh dj ldrs gSa% newThreadObject.stop();

RUNNABLE State bl State dk eryc ;s gS fd Thread Execute gksus ds fy, rS;kj gS vkSj CPU dk Attention izkIr djus dk bUrtkj dj jgk gSA pwafd ,d Single Processor Computer System ij ,d gh CPU gksrk gS vkSj ,d CPU ,d le; esa dsoy ,d gh Statement dks Execute dj ldrk gSA blfy, ,d Single Processor CPU ij Multithreaded Programming dks Maintain djus ds fy, ,d Thread Queue dk iz;ksx fd;k tkrk gSA tc ge u;k Thread Create djrs gSa] rc Threads ds Queue esa gekjk Thread Queued Up gks tkrk gS vkSj Execute gksus dk Wait djrk gSA ;fn Threads ds Queue esa mifLFkr


Java in Hindi lHkh Threads dks leku Priority izkIr gks] rks lHkh Threads dks Execute gksus ds fy, tkok }kjk Round-Robin Fashion esa CPU ij Time Slot iznku fd;k tkrk gSA bl Fashion esa tks Thread igys vkrk gS] og igys Process gksrk gSA tks Thread FkksMs le; ds fy, Suspend Mode esa tkrk gS] og Thread fQj ls Threads ds Queue ds vUr esa Join gks tkrk gS vkSj fQj ls CPU ij vius Execution dk Wait djrk gSA fofHkUu Threads dks Time Assign djus dk ;s rjhdk Time-Slicing Method dgykrk gSA ,d Thread Queue esa fofHkUu Priority okys Threads Execution ds fy, miyC/k gks ldrs gSaA ;fn ge pkgrs gSa fd dksbZ Thread fQj ls viuk Turn vkus ls igys viuk Control leku Priority okys nwljs Running Thread dks Hand-Over djs] rks bl dke dks djus ds fy, gesa yield() Method dk iz;ksx djuk gksrk gSA

RUNNIG State

RUNNING State dk eryc gS fd CPU us Thread dks viuk Time ns fn;k gS vkSj Thread Run gks jgk gSA Thread rc rd RUNNING State esa jgrk gS] tc rd fd og viuk Control fdlh nwljs Thread dks Transfer ugha dj nsrk ;k fQj fdlh High Priority Thread }kjk Thread ds Execution dks Prevent ugha dj fn;k tkrkA ,d RUNNING State dk Thread viuk Control fuEu fLFkfr;ksa esa fdlh nwljs Thread dks Hand Over

djrk gS%

1. tc Thread suspend() Method ds iz;ksx }kjk Suspend fd;k tkrk gS] rc og Thread fdlh nwljs Thread dks viuk Control Hand Over djrk gSA Suspended Thread dks fQj ls Retrieve djus ds fy, resume() Method dk iz;ksx fd;k tkrk gSA ;s Approach rc Use fd;k tkrk gS tc ge fdlh Thread dks fdlh dkj.k ls dqN le; ds fy, Suspend rks djuk pkgrs gSa] ysfdu mls Permanently Terminate djuk ugha pkgrs gSaA 2. ge ,d Thread dks sleep() Method dk iz;ksx djds Hkh Suspend Mode esa ykrs gSaA tc ge sleep() Method dk iz;ksx djds fdlh Thread dks FkksMs le; ds fy, Suspend Mode esa ykuk pkgrs gSa] rc ftrus le; ds fy, Thread dks Suspend djuk pkgrs gSa] mruk le; Milliseconds ds :i esa sleep() Method esa Argument ds :i esa Pass djrs gSaA ge bl Method esa Argument ds :i esa ftruk le; Specify djrs gSa] mruk le; chrrs gh og Thread fQj ls RUNNABLE State esa vk tkrk gSA 3. rhljs rjhds esa fdlh Thread dks fdlh Event ds Generate gksus rd Wait djus ds fy, dgk tkrk gSA ftrus le; rd og Thread fdlh Event ds Generate gksus dk Wait djrk gS] mrus le; rd Thread Suspend Mode esa jgrk gSA fdlh Thread dks tc fdlh Event dk Wait djus ds fy, Suspend Mode esa Hkstuk gksrk gS] rc gesa wait() Method dk iz;ksx djuk iMrk gSA Thread dks fQj ls RUNNABLE State esa ykus ds fy, notify() Method dk iz;ksx fd;k tkrk gSA


Java in Hindi BLOCKED State ,d Thread dks tc RUNNABLE State esa vkus ls jksdk tkrk gS] rc og Thread BLOCKED State esa gksrk gSA tc dksbZ Thread fdlh t:jr dks iwjk djus ds fy, Suspend, Sleeping ;k Waiting Mode esa gksrk gS] rc og Thread BLOCKED State esa gksrk gSA ,d BLOCKED State dk Thread “NOT RUNNABLE” State esa gksrk gS ysfdu og Thread DEAD State esa ugha gksrk gSA ;kuh ,d BLOCKED State dk Thread RUNNABLE State esa vkus esa l{ke gksrk gSA

DEAD State gj Thread dk ,d Life Cycle gksrk gSA ftl fdlh Hkh Thread ds run() Method dk Execution gks tkrk gS] og Thread mldh Natural DEAD State esa igqap tkrk gSA fQj Hkh ge fdlh Hkh le; viuh t:jr ds vuqlkj fdlh Hkh RUNNING Thread dks DEAD State esa Hkst ldrs gSaA fdlh Thread dks DEAD State esa Hkstus ds fy, gesa ml Thread ds fy, stop() Method dks Call djuk gksrk gSA fdlh Thread dks tc og RUNNING State esa gksrk gS ;k tc og BLOCKED State esa gksrk gS ;k tc og NEWBORN State esa gksrk gS] mls fdlh Hkh le; DEAD State esa Hkstk tk ldrk gSA tc ge fdlh Thread dks ,d ckj stop() Method }kjk DEAD State esa Hkst nsrs gSa] rks fQj ls ml Thread dks RUNNING State esa ugha yk ldrs gSa vkSj ml Thread ds fy, fdlh Hkh Thread Method dks Call ugha dj ldrs gSaA Program // File Name : ThreadMethods.java class NewThread extends Thread{ public void run(){ System.out.println("New Thread Started"); for(int i=1; i<=5; i++) { System.out.println("\t From NewThread i =" + i); if(i==1) yield();

}

}

} System.out.println("Exit From NewThread");

class MidThread extends Thread { public void run(){ System.out.println("Mid Thread Started"); for(int i=1; i<=5; i++) { System.out.println("\t From MidThread i =" + i);


Java in Hindi if(i==3) stop();

}

}

} System.out.println("Exit From MidThread");

class OldThread extends Thread{ public void run(){ System.out.println("Old Thread Started"); for(int i=1; i<=5; i++) { if(i==1) try{ sleep(1000); } catch(Exception excp){} System.out.println("\t From OldThread i =" + i);

}

}

} System.out.println("Exit From OldThread");

public class ThreadMethods{ public static void main(String args[]){ NewThread newThread = new NewThread(); MidThread midThread = new MidThread(); OldThread oldThread = new OldThread(); System.out.println("New Thread Started"); newThread.start(); System.out.println("Mid Thread Started"); midThread.start(); System.out.println("Old Thread Started"); oldThread.start(); System.out.println("End of the Main Thread"); } } Output New Thread Started Mid Thread Started New Thread Started From NewThread i =1 Old Thread Started End of the Main Thread From NewThread i =2


Java in Hindi From NewThread i =3 From NewThread i =4 From NewThread i =5 Exit From NewThread Mid Thread Started From MidThread i =1 From MidThread i =2 From MidThread i =3 Old Thread Started From OldThread i =1 From OldThread i =2 From OldThread i =3 From OldThread i =4 From OldThread i =5 Exit From OldThread

tc yield() Method dks Use fd;k tkrk gS] rc ;s Method Java Runtime esa Current Thread dks Sleep Mode esa Hkst nsrk gS vkSj Thread ds Queue esa fLFkr vxys Thread dks Control Transfer dj nsrk gSA tc ge bl Method dk iz;ksx djrs gSa] rc pkgs Thread Queue esa Low Priority dk gh Method D;ksa uk gks] og Execute gksrk gS vkSj mls CPU dk Attention izkIr gksrk gSA bl Program esa geus yield() Method dk iz;ksx fd;k gSA gkykafd newThread Object dk Execution igys “kq: gksrk gS] fQj Hkh tSls gh Loop ds Variable i dk eku 1 gksrk gS] Condition True gks tkrh gS vkSj ;s Thread viuk Control oldThread Object dks Pass dj nsrk gS] D;ksafd bl Thread ds ckn oldThread gh Start gksrk gSA oldThread ds Start gksrs gh og 1 Second ds fy, Suspend Mode esa pyk tkrk gS] blfy, Control fQj ls newThread esa Pass gks tkrk gS vkSj newThread dk lkjk dke iwjk gksus ds ckn Control midThread esa igqaprk gSA ogka ij Loop rhu ckj pyrk gS vkSj tSls gh i dk eku 3 gksrk gS] ;s Thread Terminate gks tkrk gSA fQj ;gka ls Control oldThread esa igqaprk gS vkSj ogka ds lHkh Statements dk Execution dj nsrk gSA

Synchronization

tc nks Threads dks leku Data dks Share djuk gksrk gS] rc gesa ;s r; djuk t:jh gksrk gS fd ,d Thread nwljs Thread }kjk Use fd, tk jgs Data dks Change ugha djsxkA mnkgj.k ds fy, ekuyks fd Program dk ,d Thread fdlh File ls fdlh Employee dh Salary Read dj jgk gS] tcfd nwljk Thread mlh File esa Employee dh Salary dks Update dj jgk gSA bl fLFkfr esa ,d Thread nwljs Thread }kjk Use fd, tk jgs Data dks Corrupt dj ldrk gSA bl izdkj dh fLFkfr;ksa ls cpus ds fy, ;s t:jh gS fd tc ,d Thread fdlh Data dks Access dj jgk gks] rks ml le; dksbZ nwljk Thread mlh Data dks rc rd Access uk dj lds tc rd fd igyk Thread viuk dke iwjk ugha dj ysrk gSA


Java in Hindi tkok gesa ;s lqfo/kk iznku djrk gS fd Multiple Threads ds fy, leku Data ij Perform fd, tkus okys Actions dks Coordinate fd;k tk ldrk gSA bl dke dks iwjk djus ds fy, Synchronized Methods ;k Synchronized Statements dk iz;ksx fd;k tkrk gSA ,d ,slk Object ftlds fy, Action dks Coordinate fd;k tkuk gksrk gS] ml Object ds Method ds lkFk synchronized Keyword dk iz;ksx djuk gksrk gSA ge fdlh synchronized Method dks ,d le; esa dsoy ,d Object ds fy, gh Call dj ldrs gSaA bl Keyword ds dkj.k ,d le; esa ,d ls T;knk Objects fdlh Synchronized Method dks Access ugha dj ikrs gSa vkSj Threads vkil dh Conflicts ls cp tkrs gSaA tkok dh gj Class o gj Object ,d Monitor ls Associated gksrk gSA ;s Monitor gh ;s r; djrk gS fd fdl izdkj ls ,d Object ;k Class fdlh Synchronized Method dks Access dj ldsxkA ;s Monitor r; djrk gS fd ,d le; esa dsoy ,d gh Object ;k Class fdlh Synchronized Method dks Access djsA tc dksbZ Object fdlh Synchronized Method dks Invoke djrk gS] rc ;s Monitor ml Method dks rc rd ds fy, Lock dj nsrk gS] tc rd og Object ml Synchronized Method dks Use dj jgk gksrk gSA tSls gh ml Object ds fy, Synchronized Method dk Execution iwjk gksrk gS] Monitor ml Method dks Release dj nsrk gS] rkfd dksbZ nwljk Object ml Method dks Use dj ldsA ;s Monitor ml le; Hkh Release gks tkrk gS] tc Synchronized Method wait() tSls fdlh Suspend Mode esa tkus okys Method dks Call dj ysrk gSA Synchronized Method ls Associated Thread rc rd ds fy, “NOT RUNNABLE” State esa pyk tkrk gS] tc rd wait() tSlk dksbZ Suspend Method Satisfy ugha gks tkrk gSA tc ;s Suspend Mode okyh Condition Satisfy gks tkrh gS] rc Thread Object “RUNNABLE” State esa pyk tkrk gSA fdlh Method dks Synchronized djus ds fy, gesa ml Method dks fuEukuqlkj Define djuk gksrk gS% public static synchronized void DisplayList(String name) { // Synchronized Codes goes here. }

Deadlock

,d ,slk Application ftlesa Multiple Threads Multiple Resources dks Use djrs gSa] rc Deadlock dh fLFkfr iSnk gks ldrh gSA ;s fLFkfr ml le; iSnk gksrh gS tc fofHkUu Threads Circular Dependency esa igqap tkrs gSaA ekuyks fd ,d Thread A fdlh Thread B ls fdlh Synchronized Method ds Release gksus dk Wait dj jgk gS tcfd Thread B Thread A ls mlh Synchronized Method ds Release gksus dk Wait dj jgk gSA bl fLFkfr esa nksuksa Threads fdlh Synchronized Method ds Release gksus dk bUrtkj djrs jgrs gSa vkSj nksuksa Threads ,d Infinite le; ds fy, Wait State esa pys tkrs gSaA blh fLFkfr dks Deadlock dh fLFkfr dgrs gSaA


Java in Hindi

Java Networking


Java in Hindi Java Networking

tkok dh ,d lcls cMh fo”ks’krk ;s gS fd ge blesa Network Programming cgqr gh ljyrk ls dj ldrs gSaA Network Programming ds vUrxZr ,sls Software cuk, tkrs gSa] rks fdlh Computer Network tSls fd Internet ;k Intranet ij Run gksrs gSa vkSj Distributed gksrs gSaA tkok esa Network Programming dks ljy cukus ds fy, cgqr lkjh Classes dks Create fd;k x;k gS vkSj ;s Classes gesa tkok dh Class Library ds :i esa JDK ds lkFk izkIr gksrh gSaA gkykafd tkok esa Network Programming djuk dkQh ljy dke gksrk gS] ysfdu fQj Hkh gesa Network Programming le>us ls igys Network ls lEcaf/kr dqN Basic Concepts dks /;ku esa j[kuk t:jh gksrk gSA

World Wide Web (WWW) Concepts

World Wide Web ,d ,slk rjhdk gksrk gS] ftlesa nqfu;ka Hkj ds yk[kksa Computers vkil esa Connected gksrs gSa vkSj vkil esa fofHkUu izdkj dh Information dks Share djrs gSa] tks fd Web Pages ;k HTML Pages ds :i esa Web ij fLFkr gksrs gSaA Web Programming djus ds fy, gesa URL (Uniform Resource Locator) ds ckjs esa tkudkjh gksuk t:jh gksrk gSA URL fdlh Web Server ij miyC/k fdlh Web Page ;k Web Site dk ,d Address gksrk gS] ftlls ml Particular Web Page ;k Site dks Identify o Access fd;k tkuk lEHko gks ikrk gSA Network ij miyC/k fdlh Page ;k Site dks Identify djus ds fy, tkok esa URL o URLConnection uke dh Classes dks Develop fd;k x;k gSA bu Classes ds Objects }kjk ge Network ij fLFkr fdlh Page ;k Site dks Identify djds vius Program esa Access dj ldrs gSaA

Distributed Programs

Network Program ,sls Program gksrs gSa] ftlesa nks vyx&vyx Computer Systems vkil esa ,d nwljs ls Connect gksrs gSa vkSj vkil esa Information dks Share djrs gSaA Network Programs esa gesa”kk de ls de nks Computers gksrs gSa vkSj nksuksa Computers ij ,d fo”ks’k izdkj dk Software Installed gksrk gS] ftlls nksuksa Computers vkil esa Connect gksdj Communication djrs gSaA

,sls Software tks fd ,d ls T;knk Computer ij leku le; esa vkil esa Connect gks dj Run gksrs gSa] vkSj fdlh fo”ks’k Problem dks Solve djrs gSa] Distributed Software dgykrs gSa vkSj ftrus Hkh Computers vkil esa Distributed Software dk iz;ksx djds fdlh leL;k dks Solve djus ds fy, Involve gksrs gSa] os lHkh Computers Network ds fgLls gksrs gSa vkSj fofHkUu Computers dk ;s Group gh Network dgykrk gSA Distributed Software vkil esa Client/Server rduhd ij vk/kkfjr gksrs gSaA Client/Server rduhd ,d ,slh rduhd gS] ftlesa fdlh ,d leL;k dks Solve djus ds fy, tks Software cuk;k tkrk gS] mls dbZ Computers feydj Use djrs gSaA bl rduhd esa ,d eq[;


Java in Hindi Computer gksrk gS] ftl ij Software ls lEcaf/kr lHkh Data dks Store fd;k tkrk gSA bl eq[; Computer dks Server dgk tkrk gSA Network ls tqMs gq, ftrus Hkh vU; Computers gksrs gSa] os lHkh Computers fofHkUu izdkj ds Data dks blh Server Computer ij Store djrs gSAa bu Computers dks Clients ;k Node dgk tkrk gSA Client Computer gesa”kk Server Computer ls gh Data dks izkIr djrk gS vkSj fofHkUu izdkj ds Data dks Server Computer ij gh Store djrs gSaA ,d Distributed Software esa Client o Server ds chp vkil esa fofHkUu izdkj ds Data dk ysu&nsu gksrk jgrk gSA Client o Server vkil esa rHkh fdlh izdkj dk Data Communication dj ldrs gSa] tc nksuksa vkil esa fdlh rjhds ls Connected gksaA Client o Server ds chp bl Connection dks Establish djus ds fy, fofHkUu izdkj dh Low-Level Classes dh t:jr gksrh gSA tkok esa bu Classes dks java.io uke ds Package esa Group fd;k x;k gS] ftudk iz;ksx djds Client o Server dks vkil esa Connect fd;k tk ldrk gSA

Protocol

Distributed Software dks vkil esa Communicate djokus ds fy, dqN NksVs&NksVs Standard Software cuk, x, gSaA ;s Software nks Computers dks vkil esa Connect djus dk dke djrs gSaA bu Software dks Protocol dgk tkrk gSA fofHkUu izdkj ds dkeksa dks Network ij Perform djus ds fy, fofHkUu izdkj ds Protocols Develop fd, x, gSaA

mnkgj.k ds fy, ;fn Internet ls fdlh File dks ,d Computer ls nwljs Computer ij Transfer djuk gks] rks ;s dke FTP (File Transfer Protocol) djrk gS] ;fn E-Mail Send djuk gks rks SMTP (Simple Mail Transfer Protocol) o E-Mail dks izkIr djuk gks] rks POP (Post Office Protocol) Use fd;k tkrk gSA blh rjg ls ;fn gesa Internet ls fdlh Web Document dks Access djuk gks] bl dke dks HTTP (Hyper Text Transfer Protocol) iwjk djrk gSA blh rjg ls fofHkUu izdkj ds vU; Internet ;k Network Related dkeksa dks iwjk djus ds fy, fofHkUu izdkj ds Protocols dks Develop fd;k x;k gSA bu Protocols ds lewg dks ,d fo”ks’k uke ls Identify fd;k tkrk gS] ftls TCP/IP ;kuh Transmission Control Protocol / Internet Protocol dgk tkrk gS vkSj tks Computer Networks TCP/IP Group ds Protocols dks Use djds vkil esa Network LFkkfir djrs gSa] mu Networks dks TCP/IP Network dgk tkrk gSA ftl rjg ls fofHkUu izdkj ds Technical Filed esa dqN fof”k’V izdkj ds dke gksrs gSa] ftUgsa Refer djus ds fy, fofHkUu izdkj ds “kCn gksrs gSa] mlh rjg ls Computer Networking Filed ls Related dqN fof”k’V izdkj ds “kCn gksrs gSa] ftudk Computer Networking Field esa viuk fo”ks’k vFkZ gksrk gSA buesa ls dqN “kCnksa dk Description fuEukuqlkj gS% IP Address tc Hkh dksbZ Computer Internet ls Connect gksrk gS] Internet }kjk ,d fo”ks’k rjhds dk iz;ksx djds Connect gksus okys gj Computer dks ,d Unique Number iznku dj fn;k 411 Any Question or Suggestion, Just Discuss Here...

Java in Hindi tkrk gSA Internet }kjk gj Computer dks fn, tkus okys bl Unique Number dks ml Computer dk IP Address dgk tkrk gSA ;s ,d 32-Bit Number gksrk gS] ftlesa pkj 8-Bit Numbers gksrs gSa vkSj pkjksa Numbers 0 ls 255 dh Range ds chp gks ldrs gSaA bu pkjksa Numbers dks ,d Dot dk iz;ksx djds ,d nwljs ls vyx fd;k tkrk gSA mnkgj.k ds fy, 170.17.8.192 fdlh le; fdlh Computer dk ,d IP Address gks ldrk gSA bl IP Number ds nks fgLls gksrs gSa% igyk fgLlk ml Network dks Identify djrk gS ftl esa Host Exist gS vkSj nwljk fgLlk fdlh Particular Host dks Identify djrk gSA tc Hkh ge Internet ls tqMrs gSa] gekjs Computer dks ,d Unique IP Number Internet }kjk Provide fd;k tkrk gS vkSj ;s Number rHkh rd gekjs Computer dks Refer djrk gS] tc rd ge Net ls Connected jgrs gSaA tSls gh ge Net ls Disconnect gksrs gSa] gesa Allot fd;k x;k IP Number fdlh vU; Computer dks Provide fd;k tk ldrk gSA ;fn ge fQj ls Net ls Connect gksrs gSa] rks fQj ls gesa ogh IP Number izkIr ugha gksxk] cfYd Internet }kjk gesa ,d u;k Number ns fn;k tk,xkA bl fLFkfr esa gekjk Computer rks ,d gh gksrk gS] ysfdu vyx&vyx le; ij Net ls Connect gksus ds dkj.k dbZ IP Numbers }kjk Identify gks ldrk gSA Host

Network ij fLFkr dksbZ ,d fof”k’V izdkj dk Computer Host dgykrk gSA pwafd Host lkekU;r;k Server dk dke djrk gS] blfy, Host gesa”kk ckdh ds vU; Computers dh rqyuk esa vf/kd Powerful gksrk gSA TCP/IP Network ds gj Host dk ,d Unique IP Address gksrk gS] ftlls ml Host dh Network ij ,d Unique igpku gksrh gSA

Hostname fdlh Hkh TCP/IP Network ds fdlh Powerful Computer dks Host cuk;k tkrk gS] tks mlds Clients dks Service Provide djrk gSA gj Host dk ,d Unique IP Address gksrk gS] ftlls ml Host dks vU; Clients Identify djrs gSaA ysfdu tc ge Internet ls tqMrs gSa] rc yk[kksa TCP/IP Networks vkil esa Connected gksrs gSa] blfy, fofHkUu izdkj ds Hosts dks Identify djus ds fy, IP Address dks ;kn j[kuk t:jh gksrk gS] rkfd ,d Client Required Host ls fdlh Service ds fy, Request dj ldsA pwafd IP Address okLro esa ,d 32-Bit Number gksrk gS vkSj fofHkUu Hosts ds IP Numbers dks ;kn j[kuk ,d dfBu dke gS] blfy, fofHkUu Hosts dks Internet dh ,d fo”ks’k Service }kjk ,d Logical Symbolic uke ns fn;k tkrk gS vkSj gesa fdlh Host dks mlds IP Number ds LFkku ij mlds uke ls ;kn j[kuk gksrk gS] tks fd rqyuk esa ljy gksrk gSA fdlh Host ds IP Address ds lkFk ,d uke Associate djus dk dke DNS (Domain Name Service) o Sun Microsystems Company dk NIS (Network Information Services) djrk gSA


Java in Hindi tc ge Net ls fdlh Web Site ds fdlh Web Page dks izkIr djuk pkgrs gSa] rc gesa ml Web Site dk Web Address fy[kuk gksrk gSA blh Web Address esa gekjs ml Host dk uke gksrk gS] ftlls ge Connect gksuk pkgrs gSaA Internet dh ftl DNS o NIS Service dk iz;ksx djds fdlh Host dks ,d uke Provide fd;k tkrk gS] ogh Service gekjs Web Address esa ls Host ds uke dks Hkh izkIr djus ds ckn Host ds uke ds vk/kkj ij ml uke ls lEcaf/kr IP Address ;k IP Number dks izkIr djrk gS vkSj gesa ml Host ij igqapk nsrk gS] ftl ij gekjh Required Site

miyC/k gksrh gSA

IETF (Internet Engineering Task Force) ;s Engineers dk ,d ,slk Group gS tks Internet ls lEcaf/kr Standards dks Maintain djus o u, Standards cukus dk dke djrk gSA Internet bls lkekU;r;k Networks dk Network dgk tkrk gSA Internet okLro esa cgqr lkjs NksVs Networks dk ,d lewg gksrk gS] tks Globally Interconnected gksrs gSaA Intranet ;s ,d NksVk Network gksrk gS] tks TCP/IP Protocols dks Use djrk gS vkSj Internet ls Connected ugha gksrk gSA ;fn ;s Internet ls Connect gksrk gS rks ,d Firewall ds Through Connect gksrk gSA Packet tc nks Computers vkil esa Connect gks dj ,d nwljs dks Information Transfer djrs gSa] rks ;s Information NksVs&NksVs VqdMksa esa foHkkftr gks dj ,d Computer ls nwljs Computer ij igqaprk gSA Information ds bu NksVs&NksVs VqdMksa dks Packets dgk tkrk gSA dbZ ckj Packets dks Datagram Hkh dgk tkrk gSA ysfdu rduhdh Lrj ij nksuksa esa ,d eq[; vUrj ;s gS fd Packet “kCn dks Network Layer ds fy, Use fd;k tkrk gS] tcfd Datagram “kCn dks Higher-Layer Message ds fy, Use fd;k tkrk gSA Protocol

Protocols Information dks Transmit djus ds fy, Use fd, tkus okys Data Formats o Messages dk ,d lewg gksrk gS] ftls ge ,d NksVs Software dh rjg eku ldrs gSaA vyx&vyx izdkj ds Networks rHkh ,d nwljs ls Communication dj ldrs gSa] tc nksuksa Networks leku Protocol dks Use djrs gSaA Protocols okLro esa dqN ,sls Standard fu;eksa dk lewg gksrk gS] tks nks vyx izdkj ds Networks ds chp Communication Establish djus dk dke djrs gSaA


Java in Hindi Protocol Stack

Networking Services dks ge fofHkUu Layers ds ,d ,sls lewg ds :i esa eku ldrs gSa] tgka Lower Layer Services dks Use djds Higher Layer Services dks Service Provide djus dk dke fd;k tkrk gSA Layers dk ;s lewg] tks fd Network Functionality Provide djrs gSa] Protocol Stack dgk tkrk gSA

Router

Router ,d fo”ks’k izdkj dk Network Hardware gksrk gSA ;s ,d ,slk Host gksrk gS tks tkurk gS fd fofHkUu izdkj ds Networks ds chp Packets dks fdl izdkj ls Forward

fd;k tk ldrk gSA

Sockets tc nks Computers vkil esa Communication djrs gSa] rc Source Computer ds fy, Destination Computer ,d Socket dh rjg Represent fd;k tkrk gSA tc ge TCP/IP ds lanHkZ esa ckr djrs gSa] rc Socket dks ,d ,sls Unique Pair ds :i esa ns[kk tkrk gS] ftlesa Source Computer dk IP Address o Port Number rFkk Destination Computer dk IP Address o Port Number gksrk gSA

Internet Protocols

TCP/IP Internet ij fLFkr fofHkUu izdkj ds Computers o Networks ds chp Communication djokus okys Communication Protocols dk ,d lewg gksrk gSA TCP/IP Suite esa eq[; :i ls fuEu Protocols gksrs gSa] 1 2 3

User Datagram Protocol (UDP) Internet Control Message Protocol (ICMP) Internet Group Multicast Protocol (IGMP)

;s lHkh Protocols feydj fofHkUu izdkj ds Hosts ds chp Information Exchange djus ds fy, ,d Standard Format Define djrs gSaA TCP/IP dk Implementation yxHkx lHkh izdkj ds Hardware o Operating System ds fy, leku :i ls dke djrk gSA blfy, lHkh izdkj ds Networks TCP/IP ds iz;ksx }kjk vkil esa Connect gks ldrs gSaA TCP/IP Network Architecture TCP/IP Network Model esa pkj Layers gksrh gSaA TCP/IP Suite dk gj Protocol bu pkjksa Layers ds fdUgha nks Layers dks vkil esa Communicate djokus dk dke djrk gSA bl Model esa Lower-Level Layer, Higher-Level Layer ds fy, Data Provide djus dk dke djrk gS] ftlls nks Host vkil esa Connect gks ikrs gSaA ;s pkjksa Layers fuEukuqlkj gSa% • • • •

1st Layer 2nd Layer 3rd Layer 4th Layer

Physical Layer (Ethernet, Token Ring, PPP) Network Layer (IP) Transport Layer (TCP, UDP) Application Layer (Telnet, HTTP, FTP, Gopher)

ge ns[k ldrs gSa fd gj Layer ds lkFk dksbZ uk dksbZ Protocol Associated gSA ;s Protocols gh Lower Layer ls Higher Layer esa Data dks Transfer djus dk dke djrs gSaA tc ,d 414 Any Question or Suggestion, Just Discuss Here...

Java in Hindi Computer dks nwljs Computer ls tksMuk gksrk gS] rc nksuksa Computers esa ,d Physical Layer gksrk gSA bl Layer esa dksbZ uk dksbZ Hardware t:j gksrk gSA

mnkgj.k ds fy, ;fn ge Internet dh ckr djsa] rks lHkh Computers esa dksbZ uk dksbZ ,slk ek/;e t:j gksrk gS] tks nks Computers dks vkil esa Connect djus dk dke djrk gSA lkekU;r;k tc Network NksVk gksrk gS] rc nks Computers dks vkil esa LAN Card }kjk tksMk tkrk gS] tks fd Computer ds Mother Board ij yxk gqvk ,d Physical Device gksrk gSA LAN }kjk tc nks Computer vkil esa Communication djrs gSa] rc nksuksa ds chp Communication djokus okyk Protocol lkekU;r;k Ethernet gksrk gSA blh rjg ls ;fn ge Internet ls tqMrs gSa rks gesa MODEM dh t:jr gksrh gS vkSj ;s Hkh Computer ds Mother Board ij Physically Attached gksrk gS vkSj lkekU;r;k ;s PPP (Point To Point Protocol ;k Peer To Peer Protocol) dk iz;ksx djds nks Computers dks vkil esa Connect djrk gSA tc Hkh dksbZ Source Computer vius Destination ij dksbZ Data Send djrk gS] rks Data ds Packets fofHkUu Layers ls xqtjrs gq, Destination ij igqaprs gSaA pfy,] Data Transfer gksus ds bl Process dks ,d mnkgj.k }kjk le>rs gSaA tc ge gekjs Web Browser esa fdlh Web Address dks Fill djds fdlh Host ls fdlh Web Document dh Request djrs gSa] rc gekjk Browser ,d HTTP Request (4th Layer) Send djus ds fy, TCP Layer (3rd Layer) dk iz;ksx djrk gSA fQj TCP Layer, IP layer (2nd Layer) ls Data dks mfpr Host ij Send djus ds fy, Request djrk gSA vUr esa IP Layer, Physical Layer (1st Layer) dks Use djds Data dks Appropriate Host ij Send dj nsrk gSA Data ftruh Hkh Layers ls xqtjrk gS] gj Layer esa ml Data ds Packet ds lkFk dqN fo”ks’k izdkj dh Information dks Packet ds Header esa Add dj fn;k tkrk gSA ftudk iz;ksx Data Packet Receive djus okyk Computer vkus okys Packet esa Embedded Data dks fQj ls mldh Original Form esa Convert djus ds fy, djrk gSA

tc Data Host dks Send dj fn;k tkrk gS] rc Data Packets Host ds (1st Layer) ij igqaprk gSA ;gka ls Packet dks Host ds IP Layer (2nd Layer) ij Hkst fn;k tkrk gSA IP Layer vkus okys Packet dks Validate djds ;s Check djrk gS] fd og Packet TCP Packet gS ;k ughaA ;fn Packet TCP Packet gksrk gS] rks bl Data Packet dks Host ds TCP Layer (3rd Layer) ij Hkst fn;k tkrk gSA vUr esa TCP Layer Data Packet dks Host ds HTTP Handle djus okys Handler (4th Layer) ij Hkst nsrk gS] tgka ij Required Web Document dks Host dk HTTP Handler [kkstrk gSA ;fn Host dks Requested Web Document izkIr gks tkrk gS] rks Host fQj ls blh Process dks Use djrk gS vkSj Requested Web Document dks Client ds Computer ij Hkst nsrk gSA tc Client o Host nksuksa leku Physical Network ds fgLls gksrs gSa] rc mijksDr Process }kjk nks Client o Server vkil esa Interaction djrs gSaA ysfdu tc Host o Client nksuksa leku Network ds fgLls ugha gksrs gSa] rc IP Layer Packets ds Route dks r; djrs gSa vkSj Packets dks rc rd fofHkUu Hosts ij Hkstrs jgrs gSa] tc rd fd Packets lgh Destination rd ugha igqap tkrsA


Java in Hindi IPv4 And IPv6 tc TCP/IP dks Develop fd;k tk jgk Fkk] rc lHkh IP Numbers dks 32-Bit dk j[kk x;k FkkA ml le; rd bl rjhds ls ftrus Unique IP Addresses curs Fks] mrus Addresses ml le; ds lHkh Hosts dks Uniquely Identify djus ds fy, i;kZIr FksA IP Number ds bl Version dks IPv4 ds uke ls tkuk tkrk gSA ysfdu vkt fLFkfr ,slh ugha gSA vkt ;s Addresses nqfu;ka Hkj ds lHkh Host Computers dks Identify djus esa l{ke ugha gSaA blfy, ,d u, IP Numbering Version dks Develop fd;k x;k gSA bl rjhds esa fdlh Computer dks fn;k tkus okyk Unique IP Number 32-Bit dk ugha cfYd 128-Bit dk gksrk gSA IP Addressing ds bl Version dks IPv6 ;k IPng uke fn;k x;k gSA bl rduhd }kjk ge yxHkx 3.4 X 1038 Different IP Address izkIr dj ldrs gSaA 32-Bit IP Address dks pkj Decimal Values }kjk Represent fd;k tkrk Fkk vkSj gj Decimal dk eku 0 ls 255 ds chp dqN Hkh gks ldrk FkkA ysfdu 128-Bit IP Address dks pkj Hexadecimal Values ds vkB Group }kjk Represent fd;k tkrk gS vkSj buds chp Dot ds LFkku ij Colon dk iz;ksx fd;k tkrk gSA tSls:5A02:1364:DD03:0432:0031:12CA:0001:BEEF IPv6 IPv4 ds fiNys Addressing Mode ds Compatible gksrk gSA blfy, os Clients tks fd IPv4 ds vk/kkj ij Develop fd, x, Fks] os lHkh IPv6 ds lkFk Hkh lkekU; rjhds ls dke djrs gSaA ;kuh IPv4 ds Clients IPv6 ds Network ij vkSj IPv6 ds Clients IPv4 ds Network ij fcuk fdlh ijs”kkuh ds lkekU; rjhds ls dke djrs gSaA IPv6 gesa fuEukuqlkj dqN vkSj Qk;ns Hkh Provide djrk gS%

1 ;s gesa Multicasting ;kuh Packets dks ,d lkFk ,d gh le; ij dbZ Destinations ij Send djus dh lqfo/kk iznku djrk gSA 2 bl IP Addressing esa Packets ds Header dk Format IPv4 dh rqyuk esa Simplified gksrk gSA 3 Network Layer ij Packets ds Contents ds Authentication o Encryption dh lqfo/kk dks Support djrk gS] ftlls Data Packets dh Security c< tkrh gSA 4 ge fdlh Special dke dks iwjk djus ds fy, Special izdkj ds Connection Create dj ldrs gSa] ftlls fdlh Data ds lkFk fo”ks’k izdkj dk Treatment fd;k tk ldrk gSA mnkgj.k ds fy, Real Time Audio Data dks rsth ls Transfer djus dh t:jr gksrh gS vkSj bl lqfo/kk dks bl IP }kjk izkIr fd;k tk ldrk gSA TCP/IP Suite esa dbZ vkSj Protocols dks Add fd;k x;k gSA blesa RTP (Real Time Protocol) o TRCP (Real Time Control Protocol) Protocols dks Add fd;k x;k gS] tks fd Video o Audio Conferencing ls lEcaf/kr Applications ds fy, Support iznku djrk gSA dqN Protocols dks TCP/IP Suite ls gVk dj mudh Functionalities dks nwljs Protocols esa Merge dj fn;k x;k gSA

mnkgj.k ds fy, IGMP Protocol tks fd Multicast Group esa Membership Provide djus ds fy, Use fd;k tkrk Fkk] vc bls TCP/IP Suite ls gVk fn;k x;k gS vkSj bldk dke vc ICMP Protocol }kjk fd;k tkrk gSA tkok Network Software Develop djus ds fy, fofHkUu izdkj dh t:jh Classes dks java.net uke ds Package ds :i esa Provide fd;k tkrk gSA tkok esa fofHkUu izdkj dh Classes dk iz;ksx djds Network Based Application Develop dj ldrs gSaA fofHkUu izdkj 416 Any Question or Suggestion, Just Discuss Here...

Java in Hindi ds Applications dks Develop djus ds fy, gesa fofHkUu izdkj ds Protocols dks Use djuk gksrk gSA gj Network Protocol dh viuh vyx fo”ks’krk,a o dfe;ka gksrh gSaA ge pkgsa rks igys ls miyC/k fofHkUu izdkj ds Protocols dks Use dj ldrs gSa ;k fQj ge gekjh t:jr ds vuqlkj u, Protocols Develop Hkh dj ldrs gSaA tkok gesa bl dke dks iwjk djus ds fy, fofHkUu izdkj dh Classes Provide djrk gSA tkok esa fofHkUu izdkj dh t:jrksa dks iwjk djus okys Network Devices ds chp Communication LFkkfir djus ds fy, fofHkUu izdkj dh Classes dks Define fd;k x;k gSA bu Classes dk iz;ksx ge gekjh t:jr ds vuqlkj dj ldrs gSaA vc ge tkok dh Networking ls lEcaf/kr Classes o muds mi;ksx dks tkusaxsA

URL Class

URL Class }kjk Web ij miyC/k Resources dks muds Uniform Resource Location dk iz;ksx djds dkQh vklkuh ls Access fd;k tk ldrk gSA os Applications o Applets tks fd World Wide Web ds Contents dks Access djds viuh fdlh t:jr dks iwjk djrs gSa] URL Class mu Programs ds fy, dkQh mi;ksxh Class gksrh gSA URL ds Content ds :i esa tks URL Specify fd;k tkrk gS] og URL Java ds ,d URL Object esa Convert gks tkrk gSA URL Object esa Content ds :i esa ,d String gksrh gS] tks mlesa Specify fd, x, URL dks Represent djrh gSA Web ij miyC/k ftl fdlh Hkh Resource dks ge Access djuk pkgrs gSa] ml Resource dk URL ge URL Class ds Object ds :i esa Specify djds Web ds ml Resource dks vius Computer ij ,d URL Object dh rjg Use dj ldrs gSaA

Socket Class

Socket Class gesa ,d Reliable o Ordered Stream Connection Provide djrk gS] tks fd ,d TCP/IP Socket Connection gksrk gSA tc Socket Create fd;k tkrk gS] rc Socket Object esa Host o Destination Computer ds Port Number dks Specify fd;k

tkrk gSA

Reliable

Client dk Host ls cuus okyk Connection Reliable blfy, gksrk gS] D;ksafd Transport Layer tks fd TCP Protocol Layer gksrh gS] oks ;s Validate djrk jgrk gS fd Send fd;k x;k Data Destination ij Bhd rjg ls Receive gks x;k gS ;k ughaA ;fn Destination ij Data Bhd rjg ls igqap tkrk gS] rks Destination Computer Source Computer dks ,d Acknowledgement Note Hkstrk gS] tks Source dks ;s crkrk gS fd mlds }kjk Hkstk x;k Data Bhd rjg ls igqap x;k gSA

ysfdu ;fn Data Bhd rjg ls Destination ij ugha igqaprk gS] rks destination Computer Source Computer dks ,d fuf”pr le;kof/k esa ;s Note ugha Hkstrk gSA ;fn ,d fuf”pr le;kof/k esa Source dks ;s Note izkIr ugha gksrk gS] rks Source mlh Data dks fQj ls Destination ij Send dj nsrk gSA tc ge fdlh Socket esa Data dks Write dj nsrs gSa] rc ge ;s eku ldrs gSa fd Data Socket ij igaqpsxkA ;fn Data Destination ij ugha igqaprk gS] rks Source Computer ,d IOException izkIr djrk gSA


Java in Hindi Socket Object }kjk tks Reliable Stream Connection Provide fd;k tkrk gS] bl izdkj ds Objects dk iz;ksx Interactive Applications Develop djus ds fy, vf/kd lQyrk ls fd;k tkrk gSA FTP o HTTP os Protocols gSa] tks vius Transport Mechanism ds :i esa TCP dk iz;kssx djrs gSaA Web ij Data dks Transfer djus ds fy, tks HTTP Protocol Use fd;k tkrk gS] og Hkh fofHkUu Hosts ds chp Communication djus ds fy, TCP dk iz;ksx djrk gSA

Ordered Stream

Ordered Stream “kCn dk eryc ;s gS fd tks Data Source ls Destination ij Transfer gksrk gS] og Data Destination ij Hkh Bhd mlh Øe esa igqaprk gS] ftl Øe esa Source ls Hkstk tkrk gSA gkykafd pwafd Data Bytes dh ,d Stream ds leku gksrk gS]

blfy, lajf{kr ugha gksrk gSA

;kuh ;fn ge 200 Characters Destination Socket ij Write djrs gSa] rks Destination Computer lHkh 200 Characters dks ,d lkFk Hkh Read dj ldrk gS vkSj ,slk Hkh gks ldrk gS fd Destination Computer igyh ckj esa dsoy 20 Characters dks gh Read djs vkSj “ks’k 180 Characters dks nwljh ckj esa Read dj ysA ServerSocket Class ;s Class ml Socket-Type dks Represent djrk gS] ftlls Establish fd;k tkus okyk Connection Communicate djuk pkgrk gSA Server Socket fdlh fn, x, Port ij Connection LFkkfir djus ds fy, blds accept() Method dk iz;ksx djds vkus okys okyh Request dks Listen djrk gSA ServerSocket Object Hkh Socket Object dh rjg gh Connection-Oriented, Ordered Stream Protocol (TCP) Offer djrk gSA

DatagramSocket Class

;s Class ,d Unreliable o Connectionless Datagram Connection Provide djrk gS] tks fd UDP/IP Connection Socket gksrk gSA Unreliable ftl rjg ls Socket Class brus Reliable gksrs gSa] tks ;s Guarantee nsrs gSa fd Data vius Destination ij igaqpsxk] ml rjg ls DatagramSocket }kjk Provide fd, tkus okys UDP Connection bl ckr dh Guarantee ugha nsrs gSaA Socket Class }kjk iznku fd, tkus okys TCP Connections bl ckr dk /;ku j[krs gSa fd ;fn Source ls Destination ij Data igqapus ls igys Lost gks tkrk gS] rks TCP Connections Data Packets dks fQj ls Destination ij Transmit djrs gSaA tcfd UDP Connection Data dks Send djus ds ckn bl ckr dh dksbZ ijokg ugha djrs gSa] fd Data Packets Destination ij igqap ik, gSa ;k ughaA bldk eryc ;s gS fd ;fn ge UDP Connection dks Use djrs gSa] rks bl ckr dk irk yxkus ds fy, fd Data Packets mlds Destination ij igqaps gSa ;k ugha] gesa fQj ls fdlh Acknowledgment rjhds dks Use djuk gksrk gSA ;fn UDP Connection }kjk Hkstk x;k


Java in Hindi Data Destination ij ugha igqaprk gS] rks UDP Connection Data dks fQj ls Destination ij Hkstus dh Try ugha djrk gSA

Connectionless

Connectionless dk eryc ;s gksrk gS fd bl izdkj ds Socket dk dksbZ Fixed Receiver ugha gksrk gSA ;kuh ge ,d gh DatagramSocket dk iz;ksx djds fofHkUu Hosts o Ports ij Data Packets dks Send dj ldrs gSaA

blfy, ;fn gesa fdlh fuf”pr Host o Port ij Data dks Send djuk gksrk gS] rc gesa Socket Connection dks gh Use djuk t:jh gksrk gSA ,d ckj tc ,d Socket vius Destination ls Connect gks tkrk gS] mlds ckn og Destination Change ugha gksrk vkSj Send fd;k tkus okyk Packet mlh Destination ij igqaprk gSA TCP ServerSocket gksrk gS] mlh rjg ls UDP DatagramServerSocket ugha gksrk gS] D;ksafd UDP Sockets fdlh Specific Destination ls Bound ugha gksrs gSa] blfy, tks Connection Packet dks Send djrk gS] ogh ml Packet dks Listen Hkh dj jgk gksrk gSA

ftl

rjg

ls

DatagramSocket Connection ls Hkstk tkus okyk Data Continuous Order esa ugha gksrk gS vkSj gj Individual Packet dh Boundary lajf{kr gksrh gSA bl izfØ;k dks ge ,sls Hkh eku ldrs gSa] tSls ge fdlh Fixed Size ds Post Card dks Mailbox esa Drop djrs gSaA

;kuh DatagramSocket Connection ds gj Packet dh Size fuf”pr gksrh gSA ;fn ge bl Connection dk iz;ksx djds pkj Packet Send djrs gSa] rks bl ckr dh dksbZ Guarantee ugha gksrh gS] fd Destination ij Hkh ;s Data mlh Øe esa igqapsaxs ftl Øe esa bUgsa Source ls Hkstk x;k gksrk gSA Destination ij ;s Packets leku Øe esa Hkh igqap ldrs gSa vkSj Hksts x, Øe ds Reverse Øe esa Hkh igqap ldrs gSaA DatagramSocket dh bu dfe;ksa dks ns[krs gq, Hkh bldh dqN ,slh fo”ks’krk,a gksrh gSa] ftldh otg ls bls Network Programming ds fy, Use fd;k tkrk gSA •

•

tc gesa fofHkUu izdkj ds Hosts ls Communicate djuk gksrk gS] rc ge bl Connection dks Use djrs gSa] D;ksafd DatagramSocket fdlh fo”ks’k Host ls Bound ugha gksrs gSaA ge leku DatagramSocket Object dks Create djrs le; mlesa vyx&vyx Hosts ds InetAddress dks Specify djds vyx&vyx Hosts ls Communication dj ldrs gSaA tc ge dksbZ ,slk Application Develop dj jgs gksrs gSa] ftlesa gesa bl ckr dh fpUrk djus dh t:jr ugha gksrh gS] fd Packet mlds Destination ij igqapk ;k ugha] rc ge bl Connection dks Use dj ldrs gSaA

Ports

lkekU;r;k lHkh Computers esa ,d Physical Layer gksrk gS] ftl ij Modem ;k LAN Card tSls Physical Devices Placed gksrs gSa] tks ,d Computer dks fdlh nwljs Computer ;k Network ls Physically Connection LFkkfir djus dh lqfo/kk iznku djrs gSaA fdlh Destination Computer ij tks Hkh Data fdlh Server ls vkrs gSa] os lHkh Data ml Physical Connection ds Through gh vkrs gSaA tks Data fdlh Server ls Client ij vkrk gS] og Data fdlh uk fdlh Particular ,d Application ds fy, Predefined gksrk gSA 419 Any Question or Suggestion, Just Discuss Here...

Java in Hindi Server ls vkus okys Data dks Client dk dkSulk Application Access djsxk] Computer dks bl ckr dh tkudkjh Ports }kjk gksrh gSA Network ij tks Hkh Data Transfer fd;k tkrk gS] og Data ftl Computer ds fy, Hkstk tkrk gS] Network ij ml Computer dks mlds IP Address }kjk igpkuk tkrk gSA ;s ,d 32-Bit Number gksrk gSA tc Server ls Hkstk x;k Data Destination Computer ij igqap tkrk gS] rc Destination Computer dk dkSulk Application ml Data dks Access djus esa l{ke gS] bl ckr dh tkudkjh Destination Computer dks ,d vU; 16-Bit Number }kjk izkIr gksrh gS] ftls Port dgk tkrk gSA

,d Connection Based Communication (TCP) esa ,d Server Application ,d Socket dks ,d Specific Port Number ls Bind djds ;s r; djrk gS fd og Client }kjk fdl Port ij vkus okyh Request dks Process djsxkA bl fLFkfr esa tc Client mlh Port Number ij dksbZ Request Hkstrk gS] rks Server ml Request dks Process djrk gSA ;kuh ekuyks fd Client 20000 Number ds Port ij Request Hkstrk gS vkSj Server 20000 Number ds Port dks Listen djrk gS] rks Server, Client dh Request dks iwjk dj nsxkA ysfdu ;fn Client 20000 Number ds Port ij Request Hkstrk gS vkSj Server 20001 Number ds Port dks Listen djrk gS] rks og Server, Client dh Request dks Process ugha dj ikrk gS] D;ksafd Server, Client ftl Port ij Request Hkst jgk gS] Server ml Port dks Read gh ugha djrk gSA blfy, Client o Server nksuksa vkil esa rHkh Communication dj ldrs gSa] tc nksuksa leku Port ij Data dks Send o Receive dj jgs gksrs gSa pwafd Port Number ,d 16-Bit Number gksrk gS] blfy, bldh Range 0 ls 65535 gksrh gSA ysfdu 0 ls 1023 Number rd ds Ports Special Services tSls fd HTTP, FTP, TELNET vkfn ds fy, Reserved gksrs gSa] blfy, ge bu Ports dks vius Application ds fdlh Socket ls Bind ugha dj ldrs gSaA bu Ports dks Well-Known Ports dgk tkrk gSA okLro esa IP Address dHkh Hkh fdlh Unique Server Program dks Identify djus esa l{ke ugha gksrk gS] D;ksafd ,d gh Computer ij ,d ls T;knk Server mifLFkr gks ldrs gSaA gj IP Address fdlh ,d Computer dks Identify djrk gS] ftlesa Ports gksrs gSa vkSj tc ge Client ;k Server ij dke dj jgs gksrs gSa] rc gesa ,d ,slk Port Choose djuk t:jh gksrk gS] tgka Client o Server nksuksa Connect gksus ds fy, Agree gksrs gSaA Computer dk Port okLro esa dksbZ Physical Location ugha gksrk gS] cfYd dsoy ,d Software Abstraction gksrk gSA Client Program dks ;s irk gksrk gS fd og fdlh nwljs Computer ls IP Address dk iz;ksx djds dSls Connect gks ldrk gS] ysfdu og ;s ugha tkurk gS fd mls Server Computer dk dkSulk Server Program Service Provide djsxkA Port Number Client Program dks blh ckr dh tkudkjh nsrk gSA Concept ;s gS fd ;fn Client fdlh Particular Port ls Connect gksuk pkgrk gS] rks bldk eryc ;gh gS fd Client ml Port ls Associated Server Application dh Services izkIr djuk pkgrk gSA okLro esa fofHkUu izdkj ds Ports ij fofHkUu izdkj dh Services miyC/k gksrh gSaA vc ;s ckr Client Program dks r; djuh gksrh gS] fd mls fdlh Server dh Services izkIr djuh gksrh gSA Client Program dks ftl Server dh Service izkIr djuh gksrh gS] Client ml Server Port ls Connect gks tkrk gSA


Java in Hindi Client/Server Technology Fundamentals

,d Network ,d ;k ,d ls T;knk Computers dks vkil esa Connect djds fdlh ,sls dke dks iwjk djrk gS] ftls dksbZ ,d vdsyk Computer ugha dj ldrkA Business, Government, Education, Hospital vkfn dqN ,sls LFkku gksrs gSa] tgka Network Create djds Computers dh Power dks iwjh rjg ls Use fd;k tkrk gSA ;fn ge fdlh Network System dks ,d Simple :i esa ns[ksa rks ,d Network cgqr lkjs Users dks fdlh ,d gh Software dks vkil esa Share djus dh lqfo/kk nsrk gSA tcfd ;fn ge Network System dks tfVy :i esa ns[ksa rks ,d Network cgqr lkjs Users dks fofHkUu izdkj ds Hardware Resources dks vkil esa Share djus dh lqfo/kk iznku djrk gSA fiNys dqN le; ls Network System esa Client/Server rduhd dks dkQh fodflr fd;k x;k gSA bl rduhd dk eq[; Goal ;s jgk gS fd nks vyx Computers gksa vkSj nksuksa dh viuh vyx izdkj dh fo”ks’krk,a gksaA tks Computer Graphics vPNh rjg ls Display dj ldrk gS] og Computer dsoy Information dks Display djus dk gh dke djs] tcfd tks Computer Data dh Processing T;knk csgrj rjhds ls dj ldrk gS] og Computer dsoy Data dh Processing dk gh dke djsA ;kuh bl rduhd esa ,d gh Application Program dks nks fgLlksa esa foHkkftr dj fn;k tkrk gS] blfy, bl izdkj dh Programming dks Distributed Programming dgrs gSaA

Client/Server Architecture Client/Server rduhd esa nks rjg ds Computer gksrs gSaA igyk Computer og gksrk gS] ftl ij fofHkUu izdkj dh Information dks Store djds j[kk tkrk gS vkSj nwljk Computer og gksrk gS] tks igys Computer ij Store fd, x, Data dks Access djrk gSA igys izdkj dk Computer Server dgykrk gS vkSj nwljs izdkj dk Computer Client dgykrk gSA tc Hkh Client dks fdlh izdkj dh Information dh t:jr gksrh gS] og Client vius Server ls ml Information dks izkIr djus ds fy, Request djrk gS vkSj Server ml Client dh Request dks iwjk djrs gq, mls mldh Required Information Hkst dj nsrk gSA World Wide Web blh Client/Server Architecture ij vk/kkfjr gSA ge tc Hkh Web ls Connect gksdj fdlh Web Document dh Request djrs gSa] gesa og Web Document ml Web Server ls izkIr gks tkrk gS] ftl ij og Stored gksrk gSA tc ge Web ls Interaction djrs gSa] ml le; pkj rjg ds Software Components dke dj jgs gksrs gSa% • • • •

,d Web Browser tks fd Client Computer ij fofHkUu izdkj ds Web Documents dks Display djus dk dke djrk gSA ,d Server Program tks fd Client Computer ds Web Browser ls Requested Web Document dks Client dks Hkstus dk dke djrk gSA og HTML Document tks fd Web Server ij Stored jgrk gSA vkSj og Communication Protocol Software tks fd Web Server o Client ds chp ds Communication dks Handle djrk gSA


Java in Hindi Client/Server Architecture ,d ,slk rjhdk gksrk Processing dks Logically VqdMksa esa foHkkftr dj fn;k Application dk Server Side dk fgLlk Application Handle djrk gS] tcfd Client Side dk fgLlk Processing dks Handle djrk gSA

gS] ftlesa fdlh Application dh tkrk gSA ,d Ideal Environment esa dh lHkh Common Processing dks Application ds User ls lEcaf/kr

Client/Server Communication Internet Applications vkil esa Internet Protocol (IP) Sockets dk iz;ksx djds Communication djrs gSaA IP ,d ,slk Fundamental Networking Protocol gksrk gS] ftlds Top ij fofHkUu izdkj ds vU; Protocols fLFkr gksrs gSa vkSj Application dh fofHkUu izdkj dh Requirements dks iwjk djrs gSaA fdlh IP Network esa ftrus Hkh Computers gksrs gSa] mu lHkh Computers dk ,d IP Address gksrk gS] tks fd 32-Bit dk ,d pkj fgLlksa esa caVk gqvk Number gksrk gS% tSls 120.232.222.12

bl Address esa igys ds nks Numbers Network dk Address gksrs gSa tcfd vfUre nks Numbers Network ds fdlh Particular Computer dks Specify djrs gSaA fofHkUu izdkj dh Multinetwork Addressing Scheme dks Use djds fofHkUu izdkj ds Networks vkil esa Communications LFkkfir djrs gSaA tc ge fdlh Information dks ,d Computer A ls nwljs Computer B ij Hkstuk pkgrs gSa] rks Computer A Computer B ds IP Address dks Use djds Data dks Computer B ij Data dks Send djrk gSA ;fn Computer B dk IP Address 123.32.12.22 gks] rks Computer A ;s Check djrk gS fd D;k og ml Specific IP Address okys Computer B dh Location dks tkurk gS fd og Computer B Network esa dgka ij fLFkr gSA ekuyks fd Computer A fdlh 206.12 ds Network dk ,d Simple Client gS] blfy, Computer A dks bl ckr dh tkudkjh gksuk fd Computer B dgka ij fLFkr gS] ukeqefdu gksrk gSA ysfdu bl fLFkfr esa Hkh Computer A Data dks ,d Default Gateway ij Hkst nsrk gS] ftlls og Data lHkh Unknown Computers ij igqap tkrk gSA tc Gateway ,sls Data dks izkIr djrk gS tks fd fdlh Specific IP Address okys Computer ds fy, gksrk gS] rks ;s Gateway ;s Check djrk gS fd D;k og ml IP Address okys Computer B dks igpkurk gS ;k ughaA gekjs bl mnkgj.k okys Local Network esa Gateway ,d izdkj dk Router gksrk gSA lkekU;r;k ;s Router dsoy mu Computers dks gh igpkurk gS] tks Computers ml Specific Local Network esa miyC/k gksrs gSaA blfy, ;s Router Hkh Computer A ds Data dks vius Default Gateway ij Hkst nsrk gS] tks fd cgqr lkjs vU; Networks ls Connected gksrk gSA gkykafd ;s Router Hkh ;s ugha tkurk gS fd 123.32.12.22 IP Address okyk Computer dgka ij fLFkr gS] fQj Hkh ;s Router Computer A ds Data dks 123.32 Number ds Network okys Getaway ij Hkst nsrk gSA fofHkUu izdkj ds Gateways ls gksrk gqvk Computer A dk Data


Java in Hindi vUr esa ,d ,sls Computer ij igqap tkrk gS] ftldks irk gksrk gS fd bl Specific IP Address okyk Computer dgka ij fLFkr gSA ftl Computer B ds fy, Computer A ls Data dks Hkstk x;k gksrk gS] ml Computer B ij Hkh dbZ ,sls Applications gks ldrs gSa] tks fd Network ls vkus okys fofHkUu izdkj ds Data ds lkFk Communication djus ds fy, Design fd, x, gksrs gSaA bl fLFkfr esa Computer A ls Hksts x, Data esa ;s Ability gksrh gS] fd og ml Application dks igpku lds] ftlds fy, Data dks Hkstk x;k gksrk gSA Computer A ls Computer B ij vkus okyk Data Computer B ds fdl Application }kjk Use fd;k tk ldsxk] bl ckr dh tkudkjh IP Address ds vfUre Piece ;kuh Port Number esa gksrh gSA Port Number ml Application dh tkudkjh nsrk gS] ftlds }kjk Computer A ls vkus okys Data dks Computer B Access dj ldrk gSA tc ge fdlh Data dks ,d Computer A ls fdlh nwljs Computer B ij Send djuk pkgrs gSa] rc gesa dsoy Computer B ds IP Address dh gh t:jr gksrh gSA Port Number dHkh Hkh bl IP Address dk fgLlk ugha gksrk gSA IP Address ;s r; djrk gS fd fdlh Packet dks fdlh Computer A ls Computer B ij fdl izdkj ls Hkstk tk ldrk gSA ge ftrus Hkh Network Applications Develop djrs gSa] mu lHkh esa IP Address dks Handle o Manage djus dh {kerk Higher Level Protocols esa igys ls gh ekStwn gksrh gSA Network Program esa Use fd, tkus okys Most Common Higher Lever Protocols TCP/IP o UDP/IP gSaA

Identifying a Computer ,d Computer ls fdlh nwljs Computer dks dksbZ Information Send djus ds fy, vkSj ;s fuf”pr djus ds fy, fd ge mlh Computer ls Connected gSa] ftlls Communication djuk pkgrs gSa] ,d ,sls rjhds dh t:jr gksrh gS] ftlls Network ls Connected lHkh Computers dks Uniquely Identify fd;k tk ldsA blds fy, IP Address (102.126.3.22) o Domain Name (www.indiaresults.com) bu nks rjhdksa dks Develop fd;k x;k gSA nksuksa gh rjhdksa esa IP Address dks Internally ,d 32-Bit Number }kjk Represent fd;k tkrk gS vkSj ge bl IP Address dh bu nksuksa Forms dks tkok }kjk fuEukuqlkj iznku fd, x, ,d Special Java Object ds :i esa Represent dj ldrs gSa] tks fd java.net uke ds Package esa miyC/k gS% Static InetAddress.getByName()

tc ge bl Method dks Use djds blesa fdlh Computer dk IP Address ;k Domain Name Argument ds :i esa nsrs gSa] rks ;s Method InetAddress Type dk ,d Object Return djrk gSSA ge tc Hkh Internet ls Connect gksrs gSa] rks gekjk Internet Service Provider (ISP) gekjs Computer dks ,d Unique ysfdu Temporary IP Address Assign dj nsrk gSA tc rd ge Internet ls Connected jgrs gSa] rc rd gekjs Computer dk IP Address Hkh mruk gh Valid jgrk gS] ftruk Internet ls tqMs vU; Computers dk IP Address Valid gksrk gSA ;fn 423 Any Question or Suggestion, Just Discuss Here...

Java in Hindi dksbZ vU; Computer gekjs Computer ds bl IP Address dks Use djds gekjs Computer ls Connect gksrk gS] rks og gekjs Computer ij Run gks jgs fdlh Web Server ;k FTP Server ls Connect gks ldrk gSA ysfdu tSls gh ge gekjs Computer dks Net ls Disconnect djrs gSa] gekjs Computer dks ISP }kjk fn;k x;k IP Address Lost gks tkrk gSA ;fn ge fQj ls Net ls Connect gksa] rks Hkh ;s t:jh ugha gksrk gS] fd gekjk ISP gesa fQj ls ogh IP Address Provide djsxkA ;kuh ge ftruh ckj Hkh Internet ls Connect gksrs gSa] gesa gekjk ISP ,d u;k IP Address Provide djrk gSA bl fLFkfr esa gekjh lcls cMh leL;k ;gh gksrh gS fd dksbZ Hkh nwljk Computer fdlh lkekU; rjhds ls gesa Uniquely Identify djds gj ckj gels Connect ugha gks ldrkA tc ge Net ls Connect gksrs gSa] ml le; gekjs ISP us gekjs Computer dks dkSulk IP Address Provide fd;k gS] bl ckr dh tkudkjh izkIr djus ds fy, ge InetAddress.getByName() Method dks Use dj ldrs gSaA vxys Program esa geus bl Method dks Use fd;k gS] tks gesa ml Computer dk IP Address Produce djds Return djrk gS] ftldk uke ge bl Program esa Argument ds :i esa Command Prompt ij nsrs gSaA Program import java.net.*; public class WhoAmI { public static void main(String[] args) throws Exception { if(args.length != 1) { System.err.println("Usage: WhoAmI ComputerName"); System.exit(1); }

}

}

InetAddress IPAddress = InetAddress.getByName(args[0]); System.out.println(IPAddress);

gj Computer dk Lo;a dk Hkh ,d IP Address gksrk gS] ftldk Domain Name “localhost” o IP Address “127.0.0.1” gksrk gSA blh rjg ls gj Computer dk ,d uke Hkh gksrk gS] ftldk irk yxkus ds fy, gesa fuEu Process dks Use djuk gksrk gS% 1 2

3

My Computer Icon ij Right Click djsaA Display gksus okys Menu ls Properties Option dks Select djsaA Display gksus okys Dialog Box esa Computer Name Tab ds vUrxZr Computer dk

uke fn[kkbZ nsrk gSA

;k


Java in Hindi Select => Start Button => Programs => Accessories => System Tools => System Information => Click

Click djus ij gesa fuEukuqlkj System Information Window fn[kkbZ nsrk gS] ftlesa System Name Option ds lkeus gekjs Computer dk uke fy[kk gksrk gSA lkekU;r;k ge gekjs Local Computer dks Refer djus ds fy, “localhost” “kCn dk Hkh iz;ksx dj ldrs gSaA

pwafd] gekjs Computer dk uke “ServerNClient” gS] blfy, bl Computer dks Net ls Connect djus ds fy, ;fn ge fuEukuqlkj Command Use djrs gSa% c:\jdk1.5\bin\java WhoAmI ServerNClient

rks gesa fuEukuqlkj Output izkIr gksrk gS% ServerNClient/199.190.90.33

vc ;fn gekjs Computer ij dksbZ Web Server Run gks jgk gks vkSj dksbZ gekjs Computer ls Connect gksuk pkgs] rks og vius Browser esa “http://199.190.90.33” URL dks Use djds rc rd ds fy, Connect gks ldrk gS] tc rd ge Internet ls Connected jgsaxsA bl rjhds dk iz;ksx djds ge gekjh fdlh Web Site dks Real Server ij Post djus ls igys Test djus ds fy, dj ldrs gSaA Network Programs ;k Distributed Programs blh rF; ij vk/kkfjr gksrs gSa fd nks Computers dks vkil esa dSls Connect fd;k tk,] rkfd os ,d nwljs dh Information Share dj ldsaA bl Program esa gesa”kk nks fgLls gksrs gSaA

igys fgLls dks Server dgk tkrk gS] tks fdlh Client ds Connection dks Accept djus ds fy, mls fdlh Port ij Listen djrk jgrk gSA Server ls Connection LFkkfir djus dk dke Client dk gksrk gS vkSj ;s dke ,d Special Client Object }kjk gksrk gS] ftls ge Client Program esa Create djrs gSaA tc ,d ckj dksbZ Client fdlh Server ls Connect gks tkrk gS] mlds ckn Client o Server nksuksa Ends ,d I/O Stream Objects ds :i esa Behave djus yxrs gSaA ,slk gks tkus ds ckn ge Client o Server nksuksa ds Connections dks bl izdkj ls Use dj ldrs gSa] tSls ge fdlh File dks Data Read/Write djus ds fy, Use djrs gSaA 425 Any Question or Suggestion, Just Discuss Here...

Java in Hindi Testing A Program Without A Network dbZ dkj.kksa ls dbZ ckj gekjs ikl nks Computers ugha gksrs gSa] ftUgsa vkil esa Client o Server ds :i esa Use djds ,d Distributed Program dks Develop fd;k tk ldsA mnkgj.k ds fy, fdlh Class Room esa Develop fd;k tk jgk dksbZ Program ,slk ugha gksrk gS] ftls Network ij LFkkfir fd;k tk ldsA bl fLFkfr esa ,d gh Computer ij Client o Serer nksuksa Programs dks Use djuk gksrk gSA Internet Protocols Develop djus okys bl ckr ls ifjfpr Fks] blfy, mUgksaus ,d Special Address localhost Create fd;k Fkk] tks fd gekjs Local Computer ds gh IP Address dks Use djrk gSA bldk Qk;nk ;s gS fd ge fcuk fdlh Network ds Hkh ,d ,slk Software Develop dj ldrs gSa] tks Network ij Run gks ldrk gSA Local Address dks Produce djus dk ,d rjhdk fuEukuqlkj gksrk gS% InetAddress localIPAddress = InetAddress.getByName(null);

;kuh ;fn ge getByName() Method esa Argument ds :i esa null Specify djrs gSa] rks ;s Method Default ds :i esa localhost dk Address Return djrk gSA InetAddress og Address gksrk gS] ftldk iz;ksx djds ge fdlh Particular Computer dks Identify djrs gSaA ge InetAddress ds Contents dks Manipulate ugha dj ldrs gSa] ysfdu ge bls Display t:j dj ldrs gSaA ge bl InetAddress dks Overloaded Static Member Method getByName(), getAllByName() ;k getLocalHost() dk iz;ksx djds izkIr dj ldrs gSaA ge String ds :i esa localhost “kCn dk iz;ksx djds Hkh Local Computer ds InetAddress dks Produce dj ldrs gSaA tSls% InetAddress localIPAddress = InetAddress.getByName(“localhost”);

ge gekjs Computer ds InetAddress dks fuEu Reserved IP Number }kjk Hkh izkIr dj ldrs gSa% InetAddress localIPAddress = InetAddress.getByName(“127.0.0.1”);

;s rhuksa gh rjhds leku Results Generate djrs gSa vkSj bu rhuksa gh rjhdksa ls ge gekjs Local Computer dks Refer dj ldrs gSaA

Socket Introduction

Internet ij fofHkUu Computers vkil esa TCP/IP Protocol }kjk Connected jgrs gSaA 1980 esa U. S. Government dh Advance Research Projects Agency (ARPA) us University Of California tks fd Berkeley esa fLFkr gS] dks TCP/IP Protocol Suite ds leku ,d dke djus okyk ,d ,slk Suite Create djus dk dke lkSaik] ftls UNIX Platform ij Implement fd;k tk ldsA ml University us tks Suite Develop fd;k mls Socket Interface uke fn;k 426 Any Question or Suggestion, Just Discuss Here...

Java in Hindi x;k] ftls ge lkekU;r;k Berkeley-Socket Interface ;k dsoy Berkeley Sockets ds uke ls tkurs gSaA Socket dsoy ,d Abstraction gksrk gS] tks nks Computers ds chp ds Connection ds Terminal dks Represent djrk gSA ;s TCP/IP Network esa ,d Connection Point dks Represent djrk gSA fdlh fn, x, Connection esa gj Computer ij ,d Socket gksrk gS vkSj ge ;s eku ldrs gSa fd nksuksa Computers ds chp ,d Virtual ;k vkHkklh Cable gksrh gS] ftlls nksuksa Computers ds Sockets vkil esa Connect gksrs gSaA Socket Interface esa tc nks Computers vkil esa Communication djuk pkgrs gSa] rc nksuksa Computers ,d Socket dk iz;ksx djrs gSaA nksuksa Computers esa ls fdlh ,d Computer dks Server cuk;k tkrk gS] tks fd ,d Socket dks Open djrk gS vkSj Connection ds fy, Wait djrk gS] ;kuh fdlh Client ds Connection dks Listen djrk gSA

nwljs Computer dks Client ds :i esa Use fd;k tkrk gS vkSj ;s Server ls Connection LFkkfir djus ds fy, Server ds Socket dks Call djrk gSA Connection dks Establish djus ds fy, Client dks dsoy mlds Server ds IP Address o Port Number dh gh t:jr gksrh gSA TCP/IP Network ds gj Computer dk ,d Unique IP Address gksrk gS vkSj ml IP Address esa Ports ,d Individual Connection dks Represent djrk gSA ,d Computer esa vkus okys Data dks izkIr djus ds fy, dbZ Ports gksrs gSa] ysfdu Data dks Computer dk dsoy ogh Port Listen djrk gS] ftlls Data dks Associate djds Hkstk x;k gksrk gSA

tkok esa fdlh nwljs Computer ls Connection Establish djus ds fy, ge ,d Socket Create djrs gSaA fQj ml Socket ds fy, ,d InputStream o ,d OutputStream dks Open fd;k tkrk gSA ,slk djus ij ge Connection dks ,d I/O Stream Object dh rjg Treat dj ldrs gSaA tkok esa nks Stream-Based Socket Classes gSa% ServerSocket Class dk iz;ksx ,d Server Program fdlh Incoming Connection dks Listen djus ds fy, djrk gS vkSj Socket Class dk iz;ksx ,d Client Program Connection dks Initialize djus ds fy,

djrk gSA

tc ,d ckj ,d Client ,d Socket Connection cuk ysrk gS] rc ServerSocket vius accept() Method dk iz;skx djds Client Socket ls lEcaf/kr ,d Socket Return djrk gS] ftldk iz;ksx djds Server Side esa Communication Perform gksrk gSA bruk gksus ds ckn gekjs ikl ,d okLrfod Socket to Socket Connection gksrk gS vkSj ge nksuksa Ends dks leku rjhds ls Treat djrs gSa D;ksafd nksuksa Ends ij leku Object gh gksrk gSA vc ge gj Socket ij InputStream Object ds lkFk getInputStream() Method o OutputStream Object ds lkFk getOutputStream() Method dk iz;ksx djds vkil esa Communication dj ldrs gSaA Socket esa Write fd, tkus okys Data dks o Socket ls izkIr fd, tkus okys Data dks ;kuh nksuksa gh izdkj ds Data dks gesa ,d Buffer esa Store djus ds ckn Use djuk gksrk gSA ServerSocket rc rd Wait djrk gS tc rd fd dksbZ Client Machine blls Connect ugha gksrkA tc dksbZ Client fdlh Wait dj jgs Server ls Connect gksrk gS] rc Server ml Client dks ,d Actual Socket Return djrk gSA ServerSocket okLro esa Lo;a ,d Socket


Java in Hindi ugha gksrk gS] cfYd tc dksbZ Client bl ServerSocket ls Connect gksrk gS] rc ;s ,d Socket Object Create djrk gSA ServerSocket dksbZ Physical Server Create djrk gS ;k Host Computer ij fdlh Socket dks Listen djrk gSA ;s Socket fdlh Incoming Connection dks Listen djrk gS vkSj fQj accept() Method dk iz;ksx djds ,d “Established” Socket Return djrk gS] ftlesa Local o Remote End Points Defined gksrs gSaA

bl rjhds dh eq[; ckr ;s gS fd Listening Socket o Established Socket nksuksa gh leku Server Socket ls Associated gksrs gSaA tks Listening Socket gksrk gS] og dsoy fdlh u, Connection dh Request dks gh Accept djrk gS fdlh Data Packet dks ughaA blfy, ServerSocket ftruk Physically egRoiw.kZ gksrk gS] mruk Programmatically ugha gksrk gSA tc ge dksbZ Server Socket Create djrs gSa] rc ge bls ,d Port Number nsrs gSaA gesa bls fdlh izdkj dk dksbZ IP Address ugha nsuk gksrk gS] D;ksafd ;s igys ls gh mlh Computer ij gksrk gS] tks Server dks Represent djrk gSA ysfdu tc ge Socket Create djrs gSa] rc gesa ml Host Computer dk IP Address o Port Number nksuksa Specify djuk gksrk gS] ftlls ge Connect gksuk pkgrs gSaA Server ServerSocket.accept() Statement }kjk tks Socket Return djrk gS] mlesa igys ls gh ;s lHkh Information gksrs gSaA

Creating A Simple Server and Client

bl mnkgj.k esa ,d Client o Server dks Socket dk iz;ksx djds le>k;k x;k gSA ftrus Hkh Servers gksrs gSa] os lHkh fdlh Client ds Connect gksus dk Wait djrs jgrs gSaA tc Connection LFkkfir gks tkrk gS] rc Connection }kjk Produce gksus okys Socket ds fy, ,d InputStream o ,d OutputStream Object dks Create fd;k tkrk gSA fQj bu nksuksa izdkj ds Objects dks Reader o Writer izdkj ds Objects esa Convert djds BufferedReader o PrintWriter Class ds Object esa Store fd;k tkrk gSA blds ckn BufferedReader Object ls tks dqN Hkh Read fd;k tkrk gS] og lcdqN PrintWriter Object esa rc rd Echo fd;k tkrk gS] tc rd fd Line dk “END” ugha feyrk gSA tc Line dk End fey tkrk gS] rc Connection Close gks tkrk gSA blh rjg ls ,d Client tc ,d Server ls Connection cukrk gS] rc og Hkh ,d InputStream Object o ,d OutputStream Object Create djrk gS vkSj Server ls Return gksus okys Data dks Server dh rjg gh bu nksuksa izdkj ds Objects dks Reader o Writer izdkj ds Objects esa Convert djds BufferedReader o PrintWriter Class ds Objects esa Store djrk gSA Client o Server nksuksa gh leku Port Number dks Use djrs gSa vkSj Client Local Computer ds IP Address dks Use djrk gS] blfy, bl Program dks Test djus ds fy, bls Network ij Store djus dh t:jr ugha gksrh gS] ge ,d gh Computer ij Client o Server nksuksa dks Test dj ldrs gSaA gekjs Program dk Server fuEukuqlkj gS% Program // Very simple server that just // echoes whatever the client sends. import java.io.*;


Java in Hindi import java.net.*; public class Server { // Choose a port outside of the range 1-1024: public static final int PORT = 8080; public static void main(String[] args) throws IOException { ServerSocket s = new ServerSocket(PORT); System.out.println("Started: " + s); try { // Blocks until a connection occurs: Socket socket = s.accept(); try { System.out.println("Connection accepted: "+ socket); BufferedReader in = new BufferedReader( new InputStreamReader( socket.getInputStream())); // Output is automatically flushed by PrintWriter: PrintWriter out = new PrintWriter( new BufferedWriter( new OutputStreamWriter( socket.getOutputStream())),true); while (true) { String str = in.readLine(); if (str.equals("END")) break; System.out.println("Echoing: " + str); out.println(str); }

}

}

}

// Always close the two sockets... } finally { System.out.println("closing..."); socket.close(); }

finally { s.close(); }


Java in Hindi bl Program esa ge ns[k ldrs gSa fd ServerSocket dks dsoy ,d Port Number dh gh t:jr gksrh gSA tc ge bl Server esa accept() Method dks Call djrs gSa] rc ;s Method rc rd ds fy, Block gks tkrk gS] tc rd fd dksbZ Client bl Server ls Connect gksus dh dksf”k”k ugha djrk gSA ;kuh ;s Method fdlh Client Program ds Connect gksus dk Wait djrk jgrk gSA tc dksbZ Client blls Connect gksrk gS] ;kuh tc Connection Accept gks tkrk gS] rc accept() Method ,d Socket Object Return djrk gS] tks fd Server/Client ds chp ds bl Connection dks Represent djrk gSA bl Program esa Sockets dks Clean up djus dk dke dkQh lko/kkuhiwoZd fd;k x;k gSA ;fn ServerSocket Constructor Fail gks tkrk gS] ;kuh ;fn ServerSocket Port Number ls Connect ugha gks ikrk gS] rks Program Terminate gks tkrk gSA ge ;gka ij ;s eku dj py jgs gSa fd ;fn ServerSocket Constructor Fail gks tkrk gS] rks bl Socket ls Connected dksbZ Hkh Network Socket Open ugha jguk pkfg,A blfy, main() Method }kjk ,d IOException Throw djok;k x;k gS] rkfd Try Block dh t:jr uk jgsA ;fn ServerSocket dk Constructor Successful gksrk gS] rks ftrus Hkh vU; Methods Call gksrs gSa] mUgsa ,d Try…Finally Block esa ;s fuf”pr djus ds fy, Monitor fd;k tkrk gS] fd Control }kjk Blocks dks pkgs fdlh Hkh rjg ls NksMk tk,] ServerSocket mfpr rjhds ls Close gksuk gh pkfg,A blh Logic dks accept() Method }kjk Return gksus okys Socket ij Hkh Apply fd;k tkrk gSA ;fn accept() Method Fail gks tkrk gS] rks gesa ;s ekuuk gksrk gS fd ;k rks Socket Exist ugha gS ;k fQj fdlh vU; Resource dks Hold dj jgk gS] blfy, bls Clean djus dh t:jr ugha gSA ;fn ;s Method Successful gksrk gS] rks Hkh blls vkxs ds Statements ,d Try…Finally Block esa gksus pkfg,] rkfd ;fn ;s Fail Hkh gks tk,] rks Hkh Socket Clean gks tk,A ;s lko/kkuh j[kuk blfy, t:jh gS D;ksafd Sockets dbZ egRoiw.kZ ysfdu Non-Memory Resources dks Use djrs gSaA tkok esa bl dke dks djus ds fy, dksbZ Destructor ugha gksrk gSA accept() Method }kjk Produce gksus okys ServerSocket o Socket nksuksa dks System.out Statement }kjk Print fd;k x;k gSA ;kuh buds toString() Methods Automatically Call gks

tkrs gSaA

Program dk vxyk fgLlk Bhd mlh rjg fn[kkbZ nsrk gS] tSls ge Reading o Writing ds fy, dksbZ File Open dj jgs gksa] ctk; blds fd ge Socket Object ds vk/kkj ij InputStream o OutputStream Objects dks Create dj jgs gSaA InputStream o OutputStream nksuksa Objects dks Øe”k% InputStreamReader o OutputStreamWriter Converter Classes dk iz;ksx djds Reader o Writer Class esa Convert fd;k x;k gSA

bl Program esa geus PrintWriter Class ds Constructor esa nwljs Argument ds :i esa “true” Pass fd;k gS] tks fd ,d boolean Flag gS vkSj ;s bl ckr dks Signify djrk gS fd


Java in Hindi gj println() Method ds ckn Output dks Flush dj fn;k tkuk pkfg,A ,slk dsoy println() Method ds lkFk gh gksrk gS] print() Method ds lkFk ;s izfØ;k Apply ugha gksrh gSA ge ftruh ckj Hkh “out” Object esa Data Write djrs gSa] gesa blds Buffer dks Flush djuk t:jh gksrk gSA bl Example esa Flush djuk blfy, t:jh gksrk gS] D;ksafd Client o Server nksuksa gh Proceed djus ;k vkxs c
vc Start Button ij Click djds Run Option dks Select djus ij ,d Dialog Box fn[kkbZ nsrk gS] ftlesa “Telnet” Type djds Enter djus ij gekjs lkeus fuEukuqlkj ,d Client Window Display gksrk gS%


Java in Hindi Server ls Connect gksus ds fy, gesa Telnet Prompt ij fp= esa fn[kkbZ ns jgs Command dks Type djds Enter djuk gksrk gSA bl Statement esa Character “o” fdlh Server ls Connection dks Open djus dk Command gksrk gSA “kCn “localhost” ml Computer dks Specify djrk gS] ftl ij Server Program Run gks jgk gSA

rhljk Parameter ml Port Number dks Specify djrk gS] ftl ij Server Program Client ls Connect gksus dk Wait dj jgk gksrk gSA pwafd ge gekjs Local Computer ij gh Server Program dks Run dj jgs gSa] blfy, nwljs Argument ds :i esa geus “localhost” “kCn Specify fd;k gS] tcfd gekjk Server, Client dks Port Number 8080 ij Listen djrk gS] blfy, rhljs Argument ds :i esa geus 8080 Use fd;k gSA tc ge ;s Command Type djds Enter Key Press djrs gSa] rc Telnet Client Window ij “Connecting To localhost…” fy[kk gqvk vkrk gS] tcfd Server Window esa gesa

“Connection accepted: Socket[addr=/127.0.0.1,port=1035,localport=8080]” Statement fn[kkbZ nsrk gS] tks crkrk gS fd Telnet Client, localhost Server ls Connect gks x;k gSA vc ge Telnet Client Window esa tks dqN Hkh Type djrs gSa] ogh String Server }kjk fQj ls gekjs Client Window esa Echo dj fn;k tkrk gSA ;fn ge Telnet Client dk Connection Server ls Break djuk pkgsa] rks gesa “END” Type djuk gksrk gSA tSls gh ge “END” Type djrs gSa] Client Window ij “Connection to host lost.” Message fy[kk gqvk fn[kkbZ nsrk gS vkSj Server Program ij “closing…” Message fy[kk gqvk fn[kkbZ nsus

yxrk gSA

Socket Transmission Modes

Sockets nks Modes: Connection Oriented o Connectionless Mode esa Connection LFkkfir dj ldrs gSaA Connection Oriented Sockets ,d Telephone dh rjg dke djrs gSa] ftlesa ,d ckj Connection LFkkfir gksus ds ckn dsoy ckr djus okys nksuksa yksxksa ds chp gh Data dk ysu&nsu gksrk gS vkSj Data Bhd mlh Øe esa ,d nwljs ds ikl igqaprs gSa] ftl Øe esa os Hksts tkrs gSaA tcfd Connectionless Sockets ,d Mail dh rjg dke djrs gSa] ftlesa muds uk rks muds Deliver gksus dh Guarantee gksrh gS uk gh muds mlh Øe esa Destination ij igqapus dh lEHkkouk gksrh gS] ftl Øe esa os Hksts x, gksrs gSaA

Bhd mlh rjg ls ftl rjg ls vyx&vyx fnuksa esa ;fn vyx&vyx Mails dks Hkstk x;k gks] rks Hkh ;s t:jh ugha gksrk gS] fd os mlh Øe esa vius Destination ij igqapsaxs ftl Øe esa mUgsa Hkstk x;k FkkA gks ldrk gS fd tks Mail igys Hkstk x;k gks og ckn esa vius Destination ij igqaps vkSj tks Mail ckn esa Hkstk x;k gks og igys vius Destination ij igqap tk,A ge dkSulk Mode Use djrs gSa ;s ckr gekjs Application dh Requirement ij fuHkZj gksrk gSA ;fn gekjs Application esa Data dh Reliability egRoiw.kZ gks rks gesa Connection-Oriented Operation Mode dks Use djuk pkfg,A File Server Connection-Oriented Mode dks Use djrs gq, cuk, tkrs gSa] D;ksafd ml rd igqapus okys lHkh Data Bhd rjhds ls o leku Øe esa Deliver gksus t:jh gksrs gSaA tc gekjs Application esa Data dh Reliability egRoiw.kZ ugha gksrh gS] rc ge User Datagram Protocol (UDP) dks Use dj ldrs gSaA Datagram ,d Self-Contained Unit gksrk gS] ftlesa Data dks Deliver djus ls lEcaf/kr lHkh izdkj dh tkudkfj;ka gksrh gSaA


Java in Hindi bls ge ,d Envelop dh rjg eku ldrs gSa] ftlds ckgj dh rjQ Delivery Address o Return Address gksrs gSa vkSj Envelop ds vUnj og Data gksrk gS] ftls Destination ij Hkstuk gksrk gSA bl Mode esa ,d Datagram Socket fdlh fof”k’V Destination Socket ls Connected ugha gksrk gS] cfYd ;s dsoy Datagram dks Send djus dk dke djrk gSA gkykafd ;s Connection Fast o Efficient gksrk gS] ysfdu ;s Connection Data dks Destination ij Deliver djus dh Guarantee ugha nsrk gSA Connection Oriented Protocol Transport Control Protocol (TCP) dks Use djrk gSA bl Connection esa Socket dks Data Send djus ls igys ml Unique Destination ls Connect gksuk t:jh gksrk gS] ftl ij og Data dks Send djuk pkgrk gSA

,d ckj Connect gks tkus ds ckn Sockets dks ,d Streams Interface (Open, Read, Write, Close) dk iz;ksx djds Access fd;k tkrk gSA ,d Socket }kjk tks Hkh dqN Hkstk tkrk gS] mls Connection dk nwljk End mlh Sequence esa izkIr djrk gS] ftl Sequence esa mls Hkstk tkrk gSA gkykafd Connection-Oriented Operation Connectionless Operation dh rqyuk esa de Efficient gksrk gS] fQj Hkh bl ckr dh Guarantee gksrh gS] fd Data mlds Destination rd t:j igaqpsxkA fdlh Client/Server Application esa lkekU;r;k ,d Server (Program) fdlh ,d Computer ij Run gksrk gS] ftlesa ,d Socket gksrk gS vkSj ;s fdlh Specific Port ls Bound gksrk gSA fdlh Client ls Connection LFkkfir djus ds fy, ;s Server vius Socket ds ml Specific Port ij fdlh Client dk Wait djrk jgrk gSA tcfd Client Side esa Client (Program) ml Computer dk Host Name tkurk gS] ftl ij Server (Program) Run gks jgk gS vkSj Server ds Socket ds ml Port Number dks Hkh tkurk gS] ftlls Server Connected gksrk gSA Server ls Connection LFkkfir djus ds fy,] Client dk Computer, Server ds Computer ij Server ds Host Computer o Port ls Connect gksus dh dksf”k”k djrk gSA ;fn lcdqN lkekU; gks rks Server, Client ds Connection dks Accept dj ysrk gSA

tc Server, Client dh Request dks Accept dj ysrk gS] rc Server ,d u;k Socket ,d vyx Port ls Bound gks tkrk gSA bls ,d u, Socket dh t:jr gksrh gS] rkfd ;s Original Socket ds fy, u, Connections dh Request dks ml le; Listen dj lds] tc ;s Connected Client dh Request dks iwjk dj jgk gksrk gSA ;fn Client ds Connection dks Server Accept dj ysrk gS] rks Client Side esa ,d Socket Create gks tkrk gS vkSj Client bl Socket dk iz;ksx Server ls Communication djus ds fy, dj ldrk gSA /;ku nsa fd Client Side dk Socket ml Port ls Bound ugha gksrk gS] ftldk iz;ksx Server ls Connect gksus ds fy, gks jgk gSA blds ctk; Client ftl Computer ij Run gks jgk gksrk gS] ml Computer dk ,d Local Port Number Client dks Assign dj fn;k tkrk gSA bruk djus ds ckn Client o Server nksuksa muds Socket esa Data dks Write djds ;k muds Socket ls Data dks Read djds Communication dj ldrs gSaA 433 Any Question or Suggestion, Just Discuss Here...

Java in Hindi lkjka”k :i esa le>sa rks Socket Network ij Run gks jgs nks Running Programs ds 2-Way Communication dk ,d Endpoint gksrk gSA Socket gesa”kk ,d Port Number ls Bound gksrk gS] ftlls TCP Layer ml Application dks Identify dj ysrk gS] ftlds fy, Data dks Hkstk x;k gksrk gSA java.net Package gesa Socket uke dh ,d Class Provide djrk gS] ftldk iz;ksx djds ge Client/Server Technology ij vk/kkfjr Application dk Client Program Create dj ldrs gSa] tks fd Network ds Server End ls Connect gks ldrk gSA

tkok gesa ServerSocket uke dh Hkh ,d Class Provide djrk gS] ftldk iz;ksx djds ge Server Side dk Application Create dj ldrs gSaA bl Class dk iz;ksx djds ge Server Side dk tks Socket Create djrs gSa] mldk iz;ksx djds Server Program Client Program dh Request dks Listen djds Client Program ls Connect gks ldrk gSA tc ge Web ls Connect gksuk pkgrs gSa] rc gesa URL Class ls Related Classes (URLConnection, URLEncoder) dk iz;ksx djuk pkfg,] D;ksafd ;s Sockets dh rqyuk esa T;knk lqfo/kktud gksrh gSaA okLro esa ULR Classes Socket Classes dh rqyuk esa Web ds fy, High Level Classes gksrh gSa] tks fd Socket Classes dks Underlying Implementation ;k Low Level Classes ds :i esa Use djrh gSaA

Reading From a Socket and Writing To a Socket

pfy,] ge ,d mnkgj.k }kjk le>us dh dksf”k”k djrs gSa fd fdl izdkj ls ,d Client Program fdlh Server Program ls Socket Class dk iz;ksx djds Connection LFkkfir dj ldrk gS vkSj Connection LFkkfir djus ds ckn Socket dk iz;ksx djds dSls Server dks Data Hkst ldrk gS vkSj Server ls Data dks Receive dj ldrk gSA bl mnkgj.k esa ,d Client Program dks Implement fd;k x;k gS] ftldk uke EchoClient gS vkSj ;s Program EchoServer uke ds Server Program ls Connect gksrk gSA Echo Server lkekU;r;k vius Client ls Data dks Receive djrk gS vkSj fQj ls mlh Data dks Client dks Return dj nsrk gSA Client, Echo Server ls Port Number 7 ij Contact dj ldrk gSA EchoClient, EchoServer ls Connect gksus ds fy, ,d Socket Create djrk gSA ;s User ls Standard Input Stream ls Input izkIr djrk gS vkSj izkIr gksus okys Input Texts dks Socket esa Write djds Echo Server ij Hkst nsrk gSA Server ij tks Text Hkstk tkrk gS] Server mlh Texts dks fQj ls Socket ds ek/;e ls Client ij Hkst nsrk gSA tc Server ls Data Client ij vk tkrk gS] rc Client ml Data dks Socket ls Read djds fQj ls Display dj nsrk gSA Program import java.io.*; import java.net.*; public class EchoClient


Java in Hindi {

public static void main(String[] args) throws IOException { Socket echoSocket = null; PrintWriter out = null; BufferedReader in = null; try{ echoSocket = new Socket("taranis", 7); out = new PrintWriter(echoSocket.getOutputStream(), true); in = new BufferedReader(new InputStreamReader(echoSocket.getInputStream())); } catch (UnknownHostException e) { System.err.println("Don't know about host: taranis."); System.exit(1); } catch (IOException e) { System.err.println("Couldn't get I/O for the connection to: taranis."); System.exit(1); } BufferedReader stdIn = new BufferedReader( new InputStreamReader(System.in)); String userInput; while ((userInput = stdIn.readLine()) != null) { out.println(userInput); System.out.println("echo: " + in.readLine()); }

}

}

out.close(); in.close(); stdIn.close(); echoSocket.close();

bl Program esa ge ns[k ldrs gSa fd EchoClient Program, EchoServer Program ls Data dks Receive djus ds fy, Data dks Socket ls gh Read djrk gS vkSj EchoClient Program, EchoServer Program dks Data Send djus ds fy, Hkh Data dks Socket esa gh Write djrk gSA bl Program ds try Block esa rhu ,sls Statements fy[ks x, gSa] tks Client Program o Server Program ds chp Socket Connection Establish djus dk dke djrs gSa vkSj Socket ds fy, ,d PrintWriter o ,d BufferedWriter Object Create djrs gSaA try { 435 Any Question or Suggestion, Just Discuss Here...

Java in Hindi

}

echoSocket = new Socket("taranis", 7); out = new PrintWriter(echoSocket.getOutputStream(), true); in = new BufferedReader(new InputStreamReader(echoSocket.getInputStream()));

bl Try Block dk igyk Statement ,d u;k Socket Object Create djrk gS vkSj mldk uke echoSocket Assign djrk gSA bl Statement esa Socket Constructor dks Argument ds :i esa ml Computer ds uke o Port Number dh t:jr gksrh gS] ftlls ge EchoClient Program dks Connect djuk pkgrs gSaA bl mnkgj.k esa geus Host Name ds :i esa “Kuldeep” “kCn dks Use fd;k gSA ;s uke gekjs Local Network ds dsoy ,d Imaginary Host Computer dks Refer dj jgk gSA tc ge bl Program dks Network ij Run djrs gSa] rc gesa bl uke ds LFkku ij Network ds fdlh Actual Host dk uke Specify djuk gksrk gSA /;ku j[ksa fd Host Name ml Host Computer dk ,d Fully Qualified IP Name gksuk t:jh gksrk gS] ftlls ge Connect gksuk pkgrs gSaA nwljs Argument ds :i esa gesa Socket ds ml Port dk Number nsuk gksrk gS] ftlls gekjk Program Connect gksuk gSA Port Number 7 og Port gS] ftl ij Echo Server Listen djrk gSA bl mnkgj.k esa geus Readers o Writers Classes dk iz;ksx fd;k gS] rkfd ;s Socket ij Unicode Characters dks Write dj ldsA Socket ds Through Server ij Data dks Hkstus ds fy,] EchoClient Program dks dsoy PrintWriter ij Data dks Write djuk gksrk gS vkSj Server Program dk Response izkIr djus ds fy,] EchoClient Program BufferedReader dks Read djrk gSA Try … Catch Block ds ckn ,d vkSj BufferedReader izdkj dk ,d Object stdIn gS] tks fd Keyboard ls izkIr Data dks Store djrk gSA blls vkxs ,d while Loop dk iz;ksx fd;k x;k gSA ;s Loop Keyboard ls ,d ckj esa ,d Line Read djrk gS vkSj mls String izdkj ds ,d Object userInput esa Store dj nsrk gSA fQj bl String izdkj ds Object esa Stored String dks lh/ks gh PrintWriter Type ds ,d Object out esa Write dj nsrk gSA ,slk djus ij out Object esa Hkstk x;k Data Server ij igqap tkrk gS] D;ksafd PrintWriter Type ds Object dks Try Block ds nwljs Statement }kjk Server ds Socket ls Connect fd;k x;k gSA while Loop dk vfUre Statement BufferedReader Object in ls ,d Line dks Read djrk gS] tks fd Try Block ds rhljs Statement }kjk Socket ls Connected gSA bl Statement esa iz;ksx fd;k x;k readLine() Method rc rd Wait djrk jgrk gS] tc rd fd Server Program Information dks fQj ls Client Program esa ugha Hkst nsrk gSA tc readLine() Method Return gksrk gS] rc EchoClient Program ds While Loop dk vfUre Statement Server ls Return gksus okys Text dks fQj ls Monitor ij Display dj nsrk gSA Program ds vUr esa lHkh Streams dks Close fd;k x;k gSA

buds Close djus dk Øe dkQh egRoiw.kZ gksrk gSA Socket dks Close djus ls igys gesa Socket ls Connected lHkh Streams dks Close djuk t:jh gksrk gSA ;kuh Socket dks gesa”kk Program ds vfUre Statement esa Close djuk pkfg,A bl rjg ls ,d Client Program dks fuEukuqlkj ikap Steps esa Develop fd;k tkrk gS% 1

lcls igys ,d Socket Open fd;k tkrk gSA


Java in Hindi 2 3 4

5

Socket ij ,d Input Stream o ,d Output Stream dks Open fd;k tkrk gSA Server ls Data dks Read djus o Server ij Data dks Write djus ds fy, bUgha Streams dk iz;ksx fd;k tkrk gSA Streams dks Close fd;k tkrk gSA Socket dks Close fd;k tkrk gSA

Working With URL

URL Internet ij miyC/k fdlh Resource dk ,d Reference ;k Address gksrk gSA tc ge gekjs Web Browser esa fdlh Web Resource dks izkIr djus ds fy, ml Web Resource dk Address (Web Address OR URL ) Input djrs gSa] rc ge ml Web Resource rd igqap tkrs gSa] ftls ge vius Web Browser esa Use djuk pkgrs gSaA Bhd blh rjg ls ;fn ge dksbZ ,slk Program Develop djrs gSa] tks Web ij miyC/k Resources dks Use djrk gS] rks ge Web ds Resource dks Find djus ds fy, vius Program esa Hkh mlds Web Address ;kuh URL dks Use dj ldrs gSaA

tkok esa URL uke dh ,d Class gksrh gS] tks fd java.net uke ds Package esa miyC/k gksrh gSA bl Class dk iz;ksx djds ge gekjs Web Based Application esa fdlh Hkh Web Resource ds URL Address dks Represent dj ldrs gSaA okLro esa URL ,d ,slh Class gS] ftlds Object esa ge fdlh Hkh Web ij fLFkr fdlh Resource dk ;k fQj gekjs Local Computer esa fLFkr fdlh Resource dk Absolute ;k Relative Address Specify djds ml Resource dks vius Program esa Use dj ldrs gSaA

What Is a URL URL ,d Internet ;k gekjs Local Computer esa miyC/k fdlh Resource ds Address dk ,d String Representation gksrk gSA URL ds nks eq[; fgLls gksrs gSa% 1

og Protocol, ftldk iz;ksx djds fdlh Resource dks Access fd;k tkuk lEHko gks ikrk gSA vkSj 2 Resource dh Location dk Address URL ds nksuksa fgLlksa dks ge fuEukuqlkj Describe dj ldrs gSa%

bl Description esa http og Protocol gS] ftldk iz;ksx djds ,d Server //java.sun.com uke ds Internet ij mifLFkr Resource dks ,d Client Computer ij Send djrk gSA bl mnkgj.k esa http (Hyper Text Transfer Protocol) dks Use fd;k x;k gS] tks fd Client Computer ij Web Documents tks fd Hyper Text Documents gksrs gSa] dks Send djus dk dke djrk gSA http ,d ,slk Protocol gS] tks Net ij miyC/k fofHkUu izdkj ds Resources dks Transfer djus esa l{ke gksrk gSA


Java in Hindi ge ns[k ldrs gSa fd Resource Name esa Resource dk Complete Address Specify fd;k x;k gSA Resource dk uke Specify djus dk Format ewy :i ls Use fd, tk jgs Protocol ij fuHkZj djrk gS] ysfdu http ds lkFk gh dbZ vU; Protocols esa Resource ds uke esa fuEukuqlkj dbZ vkSj Components miyC/k gksrs gSa% Host Name File Name Port Number Reference

ml Server Computer dk uke ftl ij Resource Stored gSA Server Computer ij fLFkr File dk iwjk Path Name og Port Number ftlls Client dks Connect gksuk gksrk gSA (Optional) Resource esa miyC/k fdlh Specific Location dk Identifier (Optional)

dbZ Protocols dks fdlh Resource dks Access djus ds fy, Host Name o File Name dh t:jr gksrh gS] tcfd bu Protocols dks Use djrs le; gesa Port Number o Reference Field dks Specify djuk t:jh ugha gksrk gSA mnkgj.k ds fy, tc ge HTTP Protocol dk iz;ksx djds fdlh Resource dks izkIr djuk pkgrs gSa] rc gesa Network ij fLFkr Server (Host Name) o Server ij mifLFkr Resource (Document) dk Path (File Name) gh Specify djuk gksrk gSA gkykafd ge blds lkFk Port Number o Reference dks Hkh Specify dj ldrs gSaA tc ge fdlh Web Site dk URL fy[krs le; mlds lkFk fdlh Document ds uke dk iz;ksx ugha djrs gSa] rc lkekU;r;k ml Web Site ds Index.htm uke dk Document gh Client dks izkIr gksrk gS] tks fd lkekU;r;k fofHkUu izdkj dh Web Sites ds fy, Default Web Document ds leku gksrk gSA ;fn ge fdlh Specific Document dks izkIr djuk pkgsa] rks mijksDr URL dks fuEukuqlkj Hkh Use dj ldrs gSa% http://java.sun.com/index.html

Creating and Manipulating URL tc ge gekjs fdlh Application esa URL dks Use djuk pkgrs gSa] rc gesa ml URL dks Access djus ds fy, URL Class dk ,d Object Create djuk gksrk gS vkSj bl Class ds Constructor dks Use djds Specific URL Address dks ,d String Argument ds :i esa Constructor esa Pass djuk gksrk gSA mnkgj.k ds fy, ekuyks fd gesa fuEu Web Address dks ,d URL Object esa Store djuk gks% http://www.indiaresults.com/

rks bls URL Object esa Store djus ds fy, gesa fuEukuqlkj Statement fy[kuk gksrk gS% URL indiaresults = new URL (“http://www.indiaresults.com/“);

bl Statement }kjk tks URL Object Create fd;k x;k gS] og URL ,d Absolute URL gSA ,d Absolute URL esa fdlh Resource rd igqapus ls lEcaf/kr lHkh t:jh Fields gksrs gSaA ;fn ge pkgsa rks ,d ,slk URL Object Hkh Create dj ldrs gSa] tks fd fdlh nwljs URL ls Relative URL Address gksrk gSA


Java in Hindi Relative URL Object esa dsoy bruh gh tkudkjh gksrh gS] ftruh Current URL ls vkxs ds fdlh vU; Resource rd igqp a us ds fy, t:jh gksrh gSaA Relative URL Specifications dks lkekU;r;k HTML Files esa Use fd;k tkrk gSA

mnkgj.k ds fy, ekuyks fd ge HelloHomePage.html uke dk ,d HTML Page cukrs gSa] ftlls nks MyMusic.html o MyPicture.html uke ds nks vU; Web Pages Linked gSa vkSj ;s nksuksa Linked Web Pages mlh Computer ds mlh Folder esa Stored gSa] ftlesa HelloHomePage.html Web Page Stored gSaA bl fLFkfr esa HelloHomePage.html Web Page esa bu nksuksa vU; Web Pages dks Link djus ds fy, gesa dsoy fuEukuqlkj Statement gh fy[kuk gksrk gS% My Music My Picture

;s URL Relative URL gSa] ftuesa URL dh iwjh Location dks Specify ugha fd;k x;k gS] cfYd dsoy ml Current Folder ds Reference esa Specify fd;k x;k gS] ftlesa HelloHomePage.html Stored gSA ge gekjs tkok Program esa ,d ,slk URL Object Hkh Create dj ldrs gSa] tks fd fdlh nwljs URL Specification ls Relative gksrk gSA mnkgj.k ds fy, ekuyks fd ge Results dh ,d Web Site ds nks jkT;ksa ds Web Pages dk Address tkurs gSa] tks fd fuEukuqlkj gSa% http://www.indiaresults.com/maharastra_results.html http://www.indiaresults.com/rajasthan_results.html

ge bu nksuksa Pages ds fy, fuEukuqlkj ,d Relative URL Object Create dj ldrs gSa% URL results = new URL(“http://www.indiaresults.com/”); URL raj_result = new URL(results, “maharastra_results.html”); URL mah_result = new URL(results, “rajasthan_results.html”)

;s Code Segment ,d ,sls URL Constructor dks Use dj jgk gS] tks gesa ,d Base URL Address ls Relative URL Object dks Create djuh dh lqfo/kk iznku dj jgk gSA ;s Constructor fuEukuqlkj gksrk gS% URL(URL baseURL, String relativeURL)

bl Constructor dk igyk Argument Create gksus okys u, URL dk Base Specify djrk gS] tcfd nwljk Argument ,d String Format esa ml Resource dks Specify djrk gS] tks fd Base URL ls Relative gSA ;fn baseURL null gks] rks ;s Constructor relativeURL dks ,d Absolute URL dh rjg Use djrk gSA blh rjg ls ;fn relativeURL esa Absolute URL gks] rks ;s Constructor baseURL dks Ignore dj nsrk gSA ;s Constructor fdlh File esa fLFkr ,d Named Anchor dks Refer djus okyk URL Object Create djus esa Hkh mi;ksxh gksrk gS] ftls Reference dgrs gSaA mnkgj.k ds fy, ekuyks fd HelloHomePage.html File esa BOTTOM uke dk ,d Named Anchor gS vkSj ge Directly Anchor dks Refer djus okyk URL Object Create djuk pkgrs gSaA bl fLFkfr esa ge Relative URL Constructor dks fuEukuqlkj Use dj ldrs gSa%


Java in Hindi URL r = new URL(HelloNetwork, “BOTTOM”);

bu Constructors ds vykok URL Objects Create djus ds fy, URL Class esa nks vkSj Constructors gksrs gSaA ;s Constructors ml fLFkfr esa mi;ksxh gksrs gSa] tc ge HTTP tSls fdlh ,sls URL ds lkFk dksbZ izfØ;k dj jgs gksrs gSa] ftlesa Host Name, File Name, Prot Number o References Components gksrs gSaA ;s nks Constructors rc mi;ksxh gksrs gSa] tc gekjs ikl fdlh Incomplete URL dk String Representation gksrk gS] ftlesa lHkh Components ugha gksrs gSa vkSj gesa bl URL ds lHkh Components dh t:jr gksrh gSA mnkgj.k ds fy, ekuyks fd ge ,d Network Browsing Panel cukuk pkgrs gSa] tks User dks Protocol, Host Name, Port Number o File Name Select djus dh lqfo/kk nsrk gSA Panel esa Select fd, x, Components ds vk/kkj ij ;fn ge URL Create djuk pkgsa] rks bl fLFkfr esa gesa fuEukuqlkj Constructor dks Use djuk gksrk gS% new URL(“http”, “www.indiaresults.com”, “/homepage.html”);

blh URL dk Equivalent URL fuEukuqlkj Create fd;k tk ldrk gS% new URL(“http://www.indiaresults.com/homepage.html”);

bl URL esa igyk Argument Protocol dks] nwljk Argument Host Name dks o rhljk Argument File ds Path Name dks Specify dj jgk gSA URL dk tks vfUre Constructor gksrk gS] mlesa ge bl Protocol dh Argument List esa Port Number dks Hkh Specify dj ldrs gSaA ;fn ge blh URL dks Port Number ds lkFk Use djuk pkgsa] rks blfy, fy, fuEukuqlkj URL Object Create dj ldrs gSa% new URL(“http”, “www.indiaresults.com”, 80, “/homepage.html”);

;k bldk Equivalent URL fuEukuqlkj Create fd;k tk ldrk gS% new URL(“http://www.indiaresults.com:80/homepage.html”);

;fn ge buesa ls fdlh Constructor dks Use djds dksbZ URL Create djrs gSa] rks ge ml URL dks ,d String Representation ds :i esa izkIr djus ds fy, gesa URL Object ds fy, toString() ;k toExternalForm() Method dks Use djuk gksrk gSA URL Create djus ds fy, ftrus Hkh Constructors dks geus Discuss fd;k gS] os lHkh URLs ,d MalformedURLException uke dk Exception Throw dj ldrs gSaA ;s Exception rc Throw gksrk gS] tc Constructor fdlh NULL URL dks ;k Unknown Protocol dks Refer djrk gSA bl Exception dks Catch o Handle djus ds fy, URL Create djrs le; gesa try . . . catch Block dk iz;ksx djuk gksrk gS] tks fd ge fuEukuqlkj dj ldrs gSa% try { URL myURL = new URL(. . .) } catch (MalformedURLException e){


Java in Hindi

}

... // exception handler code here ...

URL Objects ,sls Objects gksrs gSa] ftUgsa ,d ckj Create dj nsus ds ckn blds fdlh Attribute (Protocol, Host Name, File Name, Prot Number) dks Change ugha fd;k tk ldrk gSA ;kuh tc ge ,d URL Create djds Use dj ysrs gSa] rks mlh URL esa u;k Web Address Specify djds mls fQj ls Reuse ugha dj ldrs gSa] cfYd nwljs Web Address dks Store djus ds fy, gesa ,d vkSj u;k URL Object Create djuk t:jh gksrk gSA URL Class gesa dbZ ,sls Methods Provide djrk gS] ftudk iz;kssx djds ge fdlh URL Object ds fdlh Hkh Part (Protocol, Host Name, File Name, Prot Number) dks Extract dj ldrs gSaA blds fy, ge fuEukuqlkj Methods dks Use dj ldrs gSa% getProtocol() ;s Method URL Objects esa ls Protocol Identifier dks Return djrk gSA getHost() ;s Method URL Objects esa ls Host Name Component dks Return djrk gSA getPort() ;s Method URL Objects esa ls Port Number Component dks Return djrk gSA ;s Method ,d Integer Number Return djrk gS] tks fd Port dks Specify djrk gSA ;fn Port dks Set uk fd;k x;k gks] rks ;s Method -1 Return djrk gSA getFile() ;s Method URL Objects esa ls File Name Component dks Return djrk gSA getRef() ;s Method URL Objects esa ls Reference Component dks Return djrk gSA

,d ckr gesa”kk /;ku j[ksa fd lHkh izdkj ds URL Addresses esa ;s lHkh Components ugha gksrs gSaA URL Class esa bu Methods dks blfy, Provide fd;k x;k gS] D;ksafd HTTP URL esa ;s lHkh Components gksrs gSa vkSj ;s lcls T;knk Use fd;k tkus okyk URL gksrk gSA URL Class dks dqN gn rd HTTP Protocol dks /;ku esa j[kdj gh Develop fd;k x;k gSA bu fofHkUu izdkj ds URL Components dks vyx djus dh izfØ;k dks ge fuEu Program }kjk le> ldrs gSa% Program import java.net.*; import java.io.*; public class ParseURL { public static void main(String[] args) throws Exception { URL aURL = new


Java in Hindi URL("http://java.sun.com:80/docs/books/tutorial/intro.html#DOWNLOADING");

}

}

System.out.println("protocol = " + aURL.getProtocol()); System.out.println("host = " + aURL.getHost()); System.out.println("filename = " + aURL.getFile()); System.out.println("port = " + aURL.getPort()); System.out.println("ref = " + aURL.getRef());

Output protocol = http host = java.sun.com filename = /docs/books/tutorial/intro.html port = 80 ref = DOWNLOADING

,d URL Object Create dj ysus ds ckn ge URL ds openStream() Method dks Call djds ge URL esa Specify fd, x, Web Document ds Contents dks ,d Stream ds :i esa izkIr dj ldrs gSaA ;s Method ,d java.io.InputStream Class dk ,d Object Return djrk gS] blfy, URL esa Specify fd, x, Web Document ds Content dks Read djuk mruk gh ljy gksrk gS] ftruk fdlh Input Stream dks Read djuk gksrk gSA


Java in Hindi

Java RMI Remote Method Invocation


Java in Hindi Java RMI – Remote Method Invocation RMI Applications

RMI Applications esa lkekU;r;k nks Separate Programs gksrs gSa] ftUgsa Server Program o Client Program dgk tkrk gSA bl izdkj ds Applications esa ,d Server Application dqN Remote Objects Create djrk gS] mUgsa Accessible cukus ds fy, dqN References Create djrk gS vkSj bl ckr dk Wait djrk gS] fd dksbZ Client Software bu Remote Objects ds Methods dks Invoke djsA

blh rjg ls ,d Client Application, Server Application ds ,d ;k ,d ls T;knk Remote Objects dk Reference izkIr djrk gS vkSj fQj mu Objects ds Methods dks Invoke djrk gSA RMI og rjhdk iznku djrk gS] ftldk iz;skx djds Client o Server Communication djrs gSa vkSj ,d nwljs dks Information Pass djrs gSaA bl izdkj ds Applications dks dbZ ckj Distributed Object Application dgrs gSaA Distributed Applications os Applications gksrs gSa] tks dbZ Host Computers ij Execute gksrs gSaA fdlh ,d Host ij Execute gksus okyk Object fdlh nwljs Remote Host ds Method dks Invoke dj ldrk gSA Remotely Invoke fd;k tkus okyk Method fdlh Local Computer dks Requirement ds vk/kkj ij dksbZ eku Return dj ldrk gSA Distributed Application Develop djus ds fy, dbZ Approaches gSa] ftuesa ls fdlh dks Hkh Use fd;k tk ldrk gSA Internet o Web Distributed System ds mnkgj.k gSa] ftls Client/Server Approach ds vk/kkj ij Develop fd;k x;k gSA Data dk Transfer gksuk fdlh Hkh Distributed System dk ,d cgqr gh egRoiw.kZ Process gksrk gSA tkok esa Message Passing ds Default System ds vk/kkj ij ,d gh Java Virtual Machine esa Calling Object fdlh nwljs Called Object dks Data Transfer djrk gSA ,d Host ls fdlh nwljs Host ij Data Hkstus ds fy, Remote Method Invocation (RMI) Approach dks Use dj ldrs gSaA RMI Objects dks og lqfo/kk iznku djrk gS] ftlls os ,d Host ls nwljs Host ij Messages Hkst ldrs gSa vkSj Receive dj ldrs gSaA RMI Objects dks fofHkUu izdkj ds Hosts ls lEcaf/kr fofHkUu JVMs dks Message Hkstus o Receive djus dh lqfo/kk nsrk gSA

fdlh Hkh Distributed Object Application dh fuEu vko”;drk,a gksrh gSa% 1 Locate Remote Object ,d Application nks esa ls fdlh ,d rjhds dk iz;ksx djds fdlh Remote Object dk Reference izkIr dj ldrk gSA ,d Application vius Remote Objects dks rmiregistry dh Simple Naming Facility dk iz;ksx djds RMI ls Register djok ldrk gS vFkok ,d Application Remote Objects ds References dks Return ;k Pass djus ds fy, vius Application esa Normal Operation Define dj ldrk gSA 2

Communicate with Remote Objects Remote Objects ds lkFk dh tkus okyh Communications dh Details dks RMI }kjk Handle fd;k tkrk gSA Programmer ds n`f’Vdks.k ls ns[ksa rks Remote Communication fdlh Standard Java Method Invocation Process dh rjg gh fn[kkbZ nsrk gSA ;kuh bl rduhd esa fdlh Object ds fy, fdlh Remote Method dks Hkh mlh rjg ls Invoke fd;k tkrk gS] ftl rjg ls fdlh lkekU; Object ds Method dks Invoke fd;k tkrk gSA


Java in Hindi 3

Local Class Bytecodes For Objects That Are Passed Around RMI ,d Caller Method dks ;s lqfo/kk Provide djrk gS] fd og Remote Objects ij Hkh fdlh Local Object dks Pass dj ldrk gSA RMI fdlh Object Code ds lkFk&lkFk Object ds Data dks Load djus ds fy, Hkh t:jh Mechanism Provide djrk gSA

RMI Distributed Application ,d Registry dk iz;ksx djds fdlh Remote Object dk Reference izkIr djrk gSA Server Application Registry dks Call djds Remote Object ls ,d uke Associate ;k Bind djrk gSA Client Program Remote Objects ds uke dks Server dh bl Registry esa [kkstrk gS vkSj uke fey tkus ij Server ij ,d Method dks Invoke djrk gSA tc t:jr gksrh gS rc fdlh Object ds fy, RMI System ,d Existing Web Server dks Use djds Class ds Bytecodes dks Server ls Client esa o Client ls Server esa Load djrk gSA bl izfØ;k dks ge fuEu fp= }kjk Hkh le> ldrs gSa%

Advantage of Dynamic Code Loading

RMI dh ,d eq[; fo”ks’krk ;s gS fd ;fn fdlh Object dh Class dks Client dh Virtual Machine ij Define uk fd;k x;k gks] rks ;s Client dh Virtual Machine esa Object dh Class ds Bytecodes dks Download dj nsrk gSA

;kuh fdlh Object dh Class o Behavior, tks fd igys fdlh ,d gh Virtual Machine ij miyC/k gksrs gSa] mUgsa RMI dk iz;ksx djds nwljs ;k Remote Virtual Machine ij Hkh Transmit fd;k tk ldrk gSA RMI Objects dks mudh okLrfod Class ;k Type ds lkFk Pass djrk gS] blfy, mu Objects ds Behaviors rc Change ugha gksrs gSa] tc mUgsa nwljh Machine ij Hkstk tkrk gSA ;s izfØ;k nwljh Machine ij ,d u;k Type ;k Class miyC/k djok nsrk gS] ;kuh ,d Application ds Behaviors dks Dynamically Extend dj nsrk gSA

Remote Interfaces, Objects and Methods

fdlh Hkh vU; Application dh rjg gh] Java RMI ds vk/kkj ij Develop fd, tkus okys ,d Distributed Application esa Hkh Interfaces o Classes dk iz;kssx gksrk gSA Interfaces esa Methods dks Declare fd;k tkrk gS vkSj Classes esa mu Methods dks Implement fd;k tkrk gS] lkFk gh dqN Additional Methods dks Hkh Define fd;k tkrk gSA


Java in Hindi ,d Distributed Application esa dqN ,sls Methods Define fd, tkrs gSa] ftUgsa Remote Virtual machine ij Implement fd;k tkrk gSA os Objects ftuesa ,sls Methods gksrs gSa] ftUgsa nks vyx Virtual Machines ij Cross Form esa Call fd;k tk ldrk gS] Remote Objects dgykrs gSaA ,d Object ml le; Remote Object cu tkrk gS] tc mlesa Remote Interface dks Implement fd;k tkrk gSA fdlh Remote Object dh fuEu Characteristics gksrh gSa% • •

,d Remote Interface java.rmi.Remote Interface dks Extend djrk gSA Interface dk gj Method fdlh Hkh vU; Application Specific Exceptions ds lkFk java.rmi.RemoteException dks Hkh mlds throws Class esa Declare djrk gSA

tc fdlh Remote Object dks ,d Virtual Machine ls nwljs Virtual Machine ij Pass fd;k tkrk gS] rc RMI bl Remote Object dk ,d Non-Remote Object dh rqyuk esa vyx rjhds ls Treat djrk gSA tc fdlh Remote Object dks ,d Virtual Machine ls fdlh nwljh Virtual machine esa Pass fd;k tkrk gS] rc RMI fdlh Remote Object ds Implementation dh Receiving Virtual Machine esa ,d Copy cukus ds ctk; Remote Object ds fy, ,d Remote Stub Pass djrk gSA ;s Stub, Remote Object ds ,d Local Representative ;k Proxy dh rjg dke djrk gS vkSj Caller ds fy, Stub Remote Object dk Remote Reference gksrk gSA Caller, Remote Method dks Local Stub ij Invoke djrk gS] tks fd Remote Object dk ,d Representative gksrk gSA Remote Object ds fy, ,d Stub mlh izdkj ds Remote Interfaces dk Set Implement djrk gS] ftl izdkj dk Set Remote Object Implement djrk gSA ;s izfØ;k Stub dks ;s lqfo/kk Provide djrh gS] fd og Remote Object }kjk Implement fd, tkus okys fdlh Hkh Interface ds :i esa Cast gks ldrk gSA gkykafd bldk eryc ;s Hkh gS fd dsoy os gh Methods Call gksus ds fy, Receiving Virtual Machine ij miyC/k gksrs gSa] ftUgsa Remote Interface esa Define fd;k x;k gksrk gSA

Creating Distributed Application Using RMI

tc ge RMI dk iz;ksx djds dksbZ Distributed Application Develop djuk pkgrs gSa] rc gesa fuEukuqlkj Steps Follow djus gksrs gSa%

Design and Implement the components of Distributed Application lcls igys gesa gekjs Application ds Architecture dks r; djuk gksrk gS vkSj ;s r; djuk gksrk gS fd Application ds dkSuls Components Local Objects gksaxs vkSj fdu Components dks Remotely Accessible cukuk gksxkA bldk fu.kZ; ge fuEukuqlkj ys ldrs gSa% •

Defining The Remote Interfaces ,d Remote Interface mu Methods dks Specify djrk gS] ftUgsa Client }kjk Remotely Invoke fd;k tk ldrk gSA Design ds bl fgLls esa mu Local Objects dks Determine fd;k tkrk gS] ftUgsa bu Methods ds fy, Parameter o Return Values ds :i esa Use fd;k tkuk gksrk gSA


Java in Hindi •

Implementing The Remote Objects Remote Objects dks ,d ;k ,d ls T;knk Remote Interfaces dks Implement djuk gksrk gSA Remote Object dh Class esa vU; Local Methods o (Local ;k Remote) Interfaces ds Implementations gks ldrs gSaA ;fn fdlh vU; Local Class ds Object dks Parameter ;k Return Value ds :i esa bu Methods esa Use fd;k tk jgk gS] rks mUgsa Hkh Implement djuk t:jh gksrk gSA

•

Implementing The Clients os Clients, tks fd Remote Objects dks Use djrs gSa] mUgsa Remote Interfaces dks Define djus ds ckn fdlh Hkh le; Implement fd, tk ldrs gSa] fQj pkgs Remote Objects dks Deploy gh D;ksa uk dj fn;k x;k gksA

Compile Sources and Generate Stubs ;s ,d 2-Step Process gSA igys Step esa ge javac Compiler dks Use djds mu Source File dks Compile djrs gSa] ftuesa Remote Interfaces] Server Classes o Client Classes dks Implement fd;k x;k gksrk gSA nwljs Step esa ge rmic Compiler dks Use djds Remote Objects ds fy, Stubs Create djrs gSaA RMI, Remote Objects dh bl Stub Class dks Client Program esa ,d Proxy dh rjg Use djrk gS] rkfd Client fdlh Particular Remote Object ls Communicate dj ldsA Make Classes Network Accessible bl Step esa ge Remote Interfaces ls Associated Class Files, Stubs o vU; Class Files, ftUgsa Clients esa Download djuk gksrk gS vkSj tks Web Server }kjk Accessible gksrs gSa] dks Create djrs gSaA Start The Application Application dks Start djus ds fy, RMI Remote Object Registry, Server o Client Programs dks Start djuk gksrk gSA pfy,] ,d mnkgj.k }kjk ge bl iwjh izfØ;k dks le>us dh dksf”k”k djrs gSaA ge tks Program ;gka ij Create dj jgs gSa] blds Server esa ,d Remote Object gS] tks Clients ls fdlh Request dks izkIr djrk gS] mls Process djrk gS vkSj Client dks Result Return djrk gSA Client dh Request ml Virtual Machine ij Process gksrh gS] ftl ij Server Run gks jgk gSA bl Program dh fo”ks’krk ;s gS fd bl Program dk Server tks dke djrk gS] mls mlh Server esa Define djus dh t:jr ugha gksrh gSA

fdlh Hkh le; u, izdkj ds dke dks Perform djus ds fy, Coding dks Create fd;k tk ldrk gS vkSj mls Server ij Run gksus ds fy, Hkstk tk ldrk gSA fdlh dke dks iwjk djus ds fy, gesa ml dke ls lEcaf/kr Class esa fdlh Particular Interface dks Implement djuk gksrk gSA fdlh dke ls lEcaf/kr Class dks Server ij Hkstdj ml dke dks iwjk djok;k tk ldrk gS] fQj pkgs ml dke dks iwjk djus okyh Class dks Server Class Create o Start djus ds dkQh ckn esa Create fd;k x;k gksA dke dks iwjk djus ds fy, ftu Codes dh t:jr gksrh gS] mls RMI System }kjk Server Program esa Download fd;k tk ldrk gS vkSj fQj 447 Any Question or Suggestion, Just Discuss Here...

Java in Hindi Server ml dke dks ml Machine ds Resources dks Use djds Run djrk gS] ftl ij Server Run gks jgk gksrk gSA Random izdkj ds dkeksa dks iwjk djus dh lqfo/kk tkok Platform ds Dynamic Nature ds dkj.k izkIr gksrh gS] ftlesa RMI dk iz;ksx djds tkok ds Platform dks Network ij Extend fd;k tkrk gSA RMI fofHkUu izdkj ds Tasks dks] fcuk ml Class dh Prior Knowledge ds Dynamically Server ds Virtual Machine esa Load o Run djrk gS] ftlesa Task dks Implement fd;k x;k gSA ,d ,slk Application ftlesa Codes dks Dynamically Download djus dh {kerk gks] Behavior Based Application dgykrk gSA

Creating RMI Server

gekjk Server, Client ls tks dh Requests dks Accept djrk gS] mls Process djrk gS vkSj Client dks Results Return djrk gSA bl Server esa ,d Interface o ,d Class gSA Interface esa mu Methods dks Define fd;k x;k gS] ftUgsa Client }kjk Call fd;k tk ldrk gSA Designing A Remote Interface ge tks Server Create dj jgs gSa] ml Server dk vk/kkj ,d Protocol gS tks fdlh Job dks Server ij Submit djus] Server }kjk ml Job dks Run djus o Generate gksus okys Result dks fQj ls Client ij Hkstus dh lqfo/kk nsrk gSA bl Protocol dks ,d Interface esa Express fd;k x;k gS] ftls Server o Server ij Hksts tkus okys Object Support djrk gSA bl izfØ;k dks ge fuEu fp= }kjk le> ldrs gSa%

gj Interface esa ,d Single Method gksrk gSA Server dk Interface Job dks Process djrk gS o Generate gksus okys Result dks Submit djus dh lqfo/kk nsrk gSA tcfd Client dk Interface ;s fuf”pr djrk gS fd Server Submit fd, x, Job dks fdl izdkj ls iwjk djrk gSA comput.Comput Interface Remotely Accessible Part dks Define djrk gS] tks fd Lo;a Server gksrk gSA bldk Code fuEukuqlkj gS% Program // File Name : compute.java package compute; import java.rmi.Remote; import java.rmi.RemoteException; public interface Compute extends Remote { Object executeTask(Task t) throws RemoteException; }


Java in Hindi java.rmi.Remote Interface dks Implement djds] ;s Interface Lo;a dks bl ckr ds fy, Specify djrk gS fd blds Method dks fdlh Hkh Virtual Machine }kjk Call fd;k tk ldrk gSA bl Interface dks Implement djus okyk dksbZ Hkh Object ,d Remote Object cu tkrk

gSA

Remote Interface ds ,d Member ds :i esa Define fd;k x;k executeTask Method ,d Remote Method cu tkrk gSA blfy, bl Method dks ,slk Define djuk t:jh gks tkrk gS] tks java.rmi.RemoteException dks Throw dj ldsA

bl Exception dks RMI System }kjk ml le; Throw fd;k tkrk gS] tc dksbZ Remote Method Call ;k rks Communication LFkkfir uk dj ik, ;k fQj tc dksbZ Protocol Error Generate gks tk,A RemoteException ,d Checked Exception gksrk gS] blfy, dksbZ Hkh ,slk Code tks bl Remote Method dks Call djrk gS] mls bl Exception dks Catch djds Handle djuk

t:jh gksrk gSA

nwljs Interface dh t:jr Server ds fy, Task Type dks Define djus ds fy, gksrh gSA bl Type dk iz;ksx Compute Interface ds executeTask() Method esa Argument ds :i esa fd;k tkrk gSA comput.Task Interface, Server o Perform fd, tkus okys Job ds chp Job dks Start djus dk rjhdk iznku djrk gSA bldk Code fuEukuqlkj gS% package compute; import java.io.Serializable; public interface Task extends Serializable { Object execute(); } Task Interface execute() uke dk ,d Single Method Define djrk gSA ;s Method Return Value ds :i esa ,d Object Return djrk gS vkSj blesa dksbZ Parameter Pass ugha

fd;k tkrk gSA

;s Method fdlh rjg dk dksbZ Exception Hkh Throw ugha djrk gSA D;ksafd ;s Interface Remote Class dks Inherit ugha djrk gS] blfy, bl Interface ds bl Method ds lkFk java.rmi.RemoteException dks blds throws Clause ds lkFk List djus dh t:jr ugha gksrh gSA

Compute ds executeTask() Method o Task ds execute() Method ds Return Value dks Object Type dk Declare fd;k x;k gSA bldk eryc ;s gS fd tks Hkh Task fdlh Primary Type ds Value (int, float, char) dks Return djuk pkgrk gS] mls bu ekuksa dks muds Equivalent Wrapper Class ds Type (Integer, Float, Character) esa Convert djds mldk Object Return djuk gksxkA


Java in Hindi geus Task Interface esa java.io.Serializable Interface dks Extend fd;k gSA RMI Object Serialization Mechanism dk iz;ksx djds Java Virtual Machines ds chp esa Objects dks By Value Transport dj ldrk gS] tks fd lkekU;r;k By Reference gh Transport gksrs gSaA Compute Object }kjk fofHkUu izdkj ds mu Tasks dks Run fd;k tk ldrk gS] ftuesa Task Type dks Implement fd;k x;k gksrk gSA tks Classes bl Interface dks Implement djrh gSa] muesa Computation ls lEcaf/kr fofHkUu izdkj ds vU; Data o Methods gks ldrs gSa] tks Computation ds fy, t:jh gSaA

RMI Technology

RMI bl Specification ds vk/kkj ij Develop fd;k x;k gS fd Local Objects o Remote Objects vkil esa feydj Interoperate dj ldrs gSaA Local Objects os Objects gksrs gSa] tks Local Computer ij Execute gksrs gSa vkSj Remote Objects os Objects gksrs gSa] tks vU; Host Machines ij Execute gksrs gSaA Remote Registry Server (rmiregistry) ,d ,slk Software gksrk gS] tks Server ij Run gksrk gSA ;s Remote Registry Server vU; Hosts dks ;s lqfo/kk nsrk gS] fd os blds Registered Objects dks Remotely Access dj ldsaA Remote Registry Server esa ,d Database gksrk gS] ftlesa mu lHkh Objects dk uke gksrk gS] tks Remote Registry Server ls Register gksrs gSaA Remote Registry Server dks Start djus ds fy, gesa Command Prompt ij “Start rmiregistry” Command fy[kdj Enter djuk gksrk gSA ;s Server Port 1099 ij Listens djrk gSA

os Objects ftUgsa Remote Access ds fy, Register fd;k tkuk gksrk gS] mUgsa RemoteInterface dks Implement djuk t:jh gksrk gSA ;s Interface mu Objects dks Identify djrk gS] ftUgsa Remotely Access fd;k tkuk gksrk gSA og gj Method ftls Remotely Invoke fd;k tkuk gksrk gS] mls ,d RemoteException Throw djuk t:jh gksrk gSA bl Exception dk iz;ksx mu Errors dks Handle djus ds fy, fd;k tkrk gS] tks Remote Method dks Invoke djrs le; Generate gksrs gSaA tkok dk RMI Approach Client/Server Framework ds vk/kkj ij Organized gksrk gSA ,d Local Object tks fd Remote Method dks Invoke djrk gS] Client Object dgykrk gS vkSj og Object ftldk Method Remotely Invoke gksrk gS] Server Object dgykrk gSA tkok dk RMI Approach Stubs o Skeletons dks Use djrk gSA Stub Client Computer dk ,d Local Object gksrk gS] tks Remote Object ds fy, ,d Proxy dh rjg dke djrk gSA Stub Remote Object ds Methods Provide djrk gSA Local Object Stub ds Methods dks bl rjg ls Invoke djrk gS] tSls fd og Remote Object dk gh Method gksA Stub bu Methods dks Invoke djds Communicate djus ds fy, ,d Skeleton dk iz;ksx djrk gS] ftls Remote Host ij Implement fd;k tkrk gSA Skeleton Client Computer dk Proxy gksrk gS] tks fd Remote Host Computer ij fLFkr gksrk gSA Stub o Skeleton ,d Remote Reference Layer ds Through Communicate djrs gSaA ;s Layer Stub dks og Capability Provide djrk gS] ftlls og ,d Transport Protocol dk iz;ksx djds Skeleton ls Communicate djrk gSA RMI TCP Protocol dks Use djds Information dks Transport djrk gSA


Java in Hindi

Java Database Management


Java in Hindi Java Database Management

T;knkrj Web-Based Application Programs dks Database Management System (DBMS) ls Interact djus dh t:jr iMrh gSA DBMS os Software gksrs gSa ftudk iz;ksx Application }kjk Use dh tkus okyh Information dks Store djus ds fy, fd;k tkrk gSA mnkgj.k ds fy, ;fn ge fdlh Search Engine ls fdlh Web Site ds URL dks Search djrs gSa] rks og URL fdlh uk fdlh DBMS Software esa gh Stored jgrk gSA blh rjg ls ekuyks fd ge Online Ticket Management djus ds fy, ,d Software cukuk pkgrs gSaA rks bl izdkj dk Software cukus ds fy, ;s t:jh gksrk gS fd Software ls lEcaf/kr Data dks fdlh uk fdlh ,d O;ofLFkr rjhds ls Manage fd;k tk,A ge gesa”kk gekjs Important Data dks ,d File ds :i esa Store djds vPNh rjg ls Manage ugha dj ldrs gSaA ,sls esa Data dks Manage djuk dkQh dfBu dke gksrk gSA Data dks Manage djus ds fy, fofHkUu izdkj ds vf/kd lqjf{kr o Manageable Software cuk, x, gSaA bu Software dks DBMS Software dgk tkrk gSA gekjk Application ftu Data dks Access djrk gS] mUgsa Store djus ds fy, ge Database Management Software dk iz;ksx djrs gSaA ysfdu User vklkuh ls vius Data ds lkFk fofHkUu izdkj dk Interaction dj lds] blds fy, ,d ljy User Interface dh Hkh t:jr gksrh gSA

tc ge Data dks Store djus ds fy, SQL, Oracle ;k fdlh vU; izdkj ds DBMS Software dks pqurs gSa rc ge User Interface Development ds fy, tkok dks Use dj ldrs gSaA tc ge tkok dks User Interface Develop djus ds fy, Use djrs gSa] rc tkok dks Front-End Software o DBMS Software dks Back-End Software dgk tkrk gSA

Database Management System Software

Database vkil esa Logically Related Information dk ,d Collection gksrk gS vkSj bl Collection dks ftl izdkj ds Software }kjk Handle o Manage fd;k tkrk gS] ,sls Software dks Database Management System (DBMS) Software dgrs gSaA ;s Software gesa os Mechanism iznku djrs gSa] ftudk iz;ksx djds ge fdlh Database ds Data dks Database ls Retrieve djus] Modify djus ;k Database esa Add djus esa l{ke gks

ikrs gSaA

vkt Data dks Store djus ds fy, fofHkUu izdkj ds DBMS Software miyC/k gSa vkSj ge ftl DBMS Software dks Use djuk pkgsa] mls Use dj ldrs gSa] ysfdu fofHkUu izdkj ds DBMS Software gekjs Data dks muds Lo;a ds izdkj esa Store djrs gSaA mnkgj.k ds fy, MS-Access esa Store fd;k tkus okyk Data .MDB Format esa Save gksrk gS] tcfd MSSQL Server esa Store fd;k tkus okyk Data .DAT Format esa Save gksrk gSA DBMS Software ,d ,slk Software gksrk gS] ftls fdlh nwljs Computer ij Data dks Store djus ds fy, Install fd;k tkrk gS vkSj fdlh vkSj Computer ij fLFkr fdlh vU; Front-End ls bl Computer ds Database esa Data dks Use fd;k tk ldrk gSA ;kuh


Java in Hindi User Interface o Database nksuksa vyx&vyx Computer ij Stored gksrs gSa] fQj Hkh vkil esa feydj ,d Unit dh rjg dke dj ldrs gSAa

Database Connectivity

ge le> ldrs gSa fd gekjs Application dk Data ,d vyx Software esa Store jgrk gS tcfd ml Data dks Access djus ds fy, tks Functionality gesa DBMS Software }kjk izkIr gksrh gS] mls Use djds gekjk Front-End Software Back-End Database ls Data dks Access djus esa l{ke gks ikrk gSA ;kuh gekjk User Interface o Database nksuksa nks vyx Computer ij gks ldrs gSaA bl fLFkfr esa nks vyx Software ds chp vkil esa Data dk Interchange gksrk jgrk gSA ;kuh Front-End User Interface ls Input fd;k x;k Data Back-End Database esa Store gksrk gS vkSj t:jr iMus ij Back-End Database ls Required Data Front-End User Interface esa vkrk gSA ;s izfØ;k rHkh lEHko gks ldrh gS] tc Back-End Database o Front-End User Interface nksuksa vkil esa fdlh rjhds ls Connected gksaA User Interface dks Database ls Connect djus ds fy, ,d fof”k’V rjhds dh t:jr gksrh gSA bl rjhds dks Windows Platform ds fy, Microsoft us ODBC ds :i esa gesa iznku fd;k gSA ODBC ,d ,slk Middle Level Software gksrk gS] tks ,d Back-End Database dks ,d Front-End User Interface ls Connect dj nsrk gSA bls Open Database Connectivity (ODBC) dgk tkrk gS] tks fd Back-End Database o Front-End User Interface ds chp ,d Protocol ;k ,d Standard ds leku dke djrk gS vkSj buds chp vkil esa Communication djokus dh lqfo/kk iznku dj nsrk gSA

ODBC Application Programming Interface ( ODBC API)

ODBC API Library Routines ;k Operating System ds Functions dk ,d ,slk lewg gksrk gS rks gekjs Program dks fofHkUu izdkj ds Databases ls Connect gksus o muls Communication djus dh {kerk iznku djrk gSA dksbZ Database fdlh User Interface ls Communicate dj lds] blds fy, gesa dsoy ml DBMS Software ds ODBC Driver dks Install djuk gksrk gS] ftls ge Back-End ds :i esa Use djuk pkgrs gSaA

ekuyks fd ge Back-End ds :i esa Oracle dks Use djuk pkgrs gSaA blds fy, gesa lcls igys Oracle Database dks Computer esa Install djuk gksxk vkSj fQj vius Front-End ls Oracle dks Connect djus ds fy, vius Computer System esa Oracle ds ODBC Driver dks Install djuk gksxkA tc ge Program dks bl rjg ls Develop djrs gSa] ftlds nks fgLls gksrs gSaA igyk fgLlk Back-End Database gksrk gS] tks Data Server dh rjg dke djrk gS] tcfd nwljk fgLlk Front-End User Interface gksrk gS] tks fd Client dh rjg dke djrk gS] rc ;fn ge User Interface dks Upgrade djrs gSa] rks gesa Database esa Upgrade djus dh t:jr ugha gksrh gS vkSj ;fn ge Database dks Upgrade djrs gSa] rks gesa User Interface dks Upgrade djus dh


Java in Hindi t:jr ugha gksrh gSA ODBC Application Architecture dks ge fuEukuqlkj fp= ds :i esa eku ldrs gSa%

JDBC Application Programming Interface ( JDBC API)

Java Database Connectivity (JDBC) gesa ,sls Database-Programming API Provide djrk gS] ftldk iz;ksx djds ge tkok Programs dks Front-End dh rjg Use djus esa l{ke

gks ikrs gSaA

pwafd ODBC APIs dks “C” Language tSlh Programming Language esa Develop fd;k x;k gksrk gS] ftuesa Pointers o vU; izdkj ds Concepts dk iz;ksx fd;k tkrk gS] blfy, tkok bu ODBC APIs dks Direct Support ugha djrk gS vkSj buls Directly Communication djus esa l{ke ugha gks ikrk gS] D;ksafd tkok Pointers tSls Concept dks Support ugha djrk gSA bl fLFkfr esa tkok Front-End ds :i esa dke djs vkSj Back-End ds :i esa fLFkr DBMS Software ls Communication dj lds] blds fy, JavaSoft Company us JDBC-ODBC Bridge Driver API Develop fd, gSa] tks fd JDBC API dks ODBC API esa Translate djus dk dke djrs gSaA budk iz;ksx ODBC Driver APIs ds lkFk esa fd;k tkrk gSA JDBC Drivers vkt gesa dbZ Categories esa miyC/k gSa] tks fd fuEukuqlkj gSa% • • • •

JDBC-ODBC Bridge + ODBC Driver Native API Partly Java Driver JDBC-Net Pure Java Driver Native Protocol Pure Java Driver

JDBC Application Architecture dks ge fuEukuqlkj fp= ds :i esa eku ldrs gSa%


Java in Hindi

JDBC Driver Manager

JDBC Driver Manager JDBC Architecture dk eq[; vk/kkj gSA JDBC Driver Manager ds Functions gekjs Application esa Specify fd, x, Appropriate Driver ls gekjs Java Application dks Connect djus dk dke djrs gSaA

JDBC-ODBC Bridge Sun Microsystems us gesa JDBC ds ,d fgLls ds :i esa ,d ,slk Driver Provide fd;k gS] ftldk iz;ksx djds fdlh ODBC Data Source dks JDBC }kjk Access fd;k tk ldrk gSA ;s Driver ODBC Data Source o Java Application ds chp ,d Bridge dk dke djrk gS] blfy, bl Driver dks JDBC-ODBC Bridge uke fn;k x;k gSA bl Bridge dks JdbcOdbc.class ds :i esa Implement fd;k x;k gS vkSj ODBC Drivers dks Access djus ds fy, blesa ,d Native Library dk iz;ksx fd;k x;k gSA Windows Platform ds fy, bl Native Library dk uke JDBCODBC.DLL gksrk gSA

Installing The ODBC Driver

ODBC Driver dks Configure djus ds fy, gesa lcls igys Control Panel esa tkuk gksrk gSA Control Panel esa fuEukuqlkj ,d Data Source (ODBC) Driver Configuration Icon gksrk gS] ftls Double Click djuk gksrk gSA

bl Icon ij Double Click djus ij gekjs lkeus fuEukuqlkj ,d ODBC Data Source Administrator Dialog Box Display gksrk gS%


Java in Hindi

ekuyks fd gekjk Database geus Microsoft Access esa cuk;k gSA bl fLFkfr esa gesa User DSN Tab ds “User Data Source:” uke dh List esa fn[kkbZ nsus okys “MS Access Database” uke ds dks pquuk gksrk gSA bl Option dks puus ds ckn “Configure…” uke ds Button ij Click djuk gksrk gSA tc ge bl Button dks Click djrs gSa] rc gekjs lkeus fuEukuqlkj vxyk Dialog Box Display gksrk gS%

bl Dialog Box ij gesa dbZ Buttons fn[kkbZ nsrs gSaA ;fn ge u;k Database Create djuk pkgsa] rks gesa “Create…” uke ds Button dks Click djuk gksrk gSA ysfdu pwafd ge ;s eku jgs gSa fd geus gekjk Database igys gh Create dj fy;k gS] blfy, ml Created Database dks vius Data Source ls Connect djus ds fy, gesa “Select…” Button ij Click djuk gksrk gSA tc ge bl Button ij Click djrs gSa] rc gekjs lkeus fuEukuqlkj ,d vkSj Dialog Box Display gksrk gS%


Java in Hindi

bl Dialog Box esa gesa ml Database dks Select djuk gksrk gS] ftls ge tkok Front-End ls Connect djuk pkgrs gSaA okafNr Database dks Select djus ds ckn gesa OK Button ij Click djuk gksrk gSA tc ge OK Button ij Click djrs gSa] rc ge fQj ls fiNys Dialog Box ij igqap tkrs gSaA bl Dialog Box ij Hkh ,d OK Button gksrk gS] ftl ij gesa Click djuk gksrk gSA tc ge OK ij Click djrs gSa] rc ge lcls igys Dialog Box ij igqap tkrs gSaA ;gka ij Hkh gesa OK ij gh Click djuk gksrk gS vkSj gekjk Database “MS Access Database” uke ds User DSN ls Connect gks tkrk gSA ;fn ge fdlh vkSj uke dk ,d u;k ODBC Data Source Create djuk pkgsa] rks ;s dke djus ds fy, gesa “ODBC Data Source Administrator” Dialog Box esa “Configure…” Button ds LFkku ij “Add…” Button dks Click djuk gksrk gSA tc ge “Add…” Button ij Click djrs gSa] rc gekjs lkeus fuEukuqlkj “Create New Data Source” uke dk Dialog Box vkrk gSA bl Dialog Box esa ge ml Database ds ODBC Driver Select djrs gSa] ftlls Front-End dks Connect djuk gksrk gSA pwafd gesa ;gka ij MSAccess ls Front-End dks Connect djuk gS] blfy, ge ;gka ij fuEukuqlkj “Microsoft Access Driver (*.mdb)” Option dks Select djrs gSaA

bl Option dks Select djds Finish Button ij Click djrs gh gekjs lkeus fuEukuqlkj ,d vkSj u;k Dialog Box Display gks tkrk gSA bl Dialog Box esa gesa gekjs u, Data Source DSN dk uke Specify djuk gksrk gS vkSj “Select…” Button ij Click djds ml Database dks Select djuk gksrk gS] ftls ge Front-End ls Connect djuk pkgrs gSaA


Java in Hindi

ge ftl Database dks Select djrs gSa] ml Database dk uke fp= esa n”kkZ, x, Rectangle ds LFkku ij fn[kkbZ nsus yxrk gSA Data Source dk uke nsus vkSj Database Select djus ds ckn gesa bl Dialog Box ij fLFkr OK Button dks Click djuk gksrk gSA tc ge OK Button ij Click djrs gSa] rc gekjs lkeus fuEukuqlkj fiNyk Dialog Box Display gksrk gS] ftlesa ,d u;k “User Data Source” fn[kkbZ nsus yxrk gSA

bl Dialog Box ij fLFkr OK Button ij Click djds ge bl Dialog Box dks Hkh Close dj ldrs gSaA tc ge bl iwjh izfØ;k dks T;ksa dk R;ksa viukrs gSa] rc gesa gekjs Database ls Connect gksus dk ,d Open Connection izkIr gks tkrk gS] ftlesa gekjk Database Embedded gksrk gSA ge bl Data Source Connection dk iz;ksx djds fdlh Hkh FrontEnd Application ls Connect gks ldrs gSa vkSj Connected Database ds Data dks Access djus esa l{ke gks tkrs gSaA

Connection to A Database

tkok esa java.sql uke ds Package esa fdlh Database ls Connection LFkkfir djus ls lEcaf/kr Classes Define dh xbZ gSaA ge fdlh ,d Application esa ,d ;k ,d ls T;knk Databases ls Connection LFkkfir djus ds fy, ,d ;k ,d ls T;knk Connection Objects Create dj ldrs gSaA Database ls Connection Establish djus ds fy, gesa JDBC-ODBC Driver dks Operating System esa Register djokuk gksrk gSA


Java in Hindi bl Driver dks Register djokus ds fy, gesa Class uke dh Class ds forName() uke ds Method dks Call djuk gksrk gSA Driver dks Operating System esa Register djokus ds ckn DriverManager Class ds getConnectoin() Method dks Call djds Data Source o Front End ds chp Connection Establish djuk gksrk gSA fdlh Database dks Identify djus ds fy, gesa ml Database dh Location dk irk yxkuk gksrk gSA JDBC URL ,d String gksrk gS] tks fdlh Database dks Identify djrk gSA ;s JDBC URL fuEukuqlkj rhu fgLlksa esa caVk gksrk gS% :_{:_{bl String esa ,d JDBC URL esa bl LFkku ij gesa”kk jdbc gksrk gSA _{Database ls Front-End dks fdl izdkj ls Connect fd;k tk jgk gS] bl Connectivity ds Mechanism dks bl LFkku ij Specify fd;k tkrk gSA lkekU;r;k tc Database ls Data dks Retrieve djus dk rjhdk ODBC-JDBC Bridge gksrk gS] rc bl SubProtocol ds LFkku ij odbc dk iz;ksx fd;k tkrk gSA _{bl LFkku ij gesa ml Database dk uke Specify djuk gksrk gS] ftlls ge Front-End dks Connect djuk pkgrs gSaA

ekuyks fd ge Java Front-End ls MS-Access esa cuk, x, Address uke ds Database dks Connect djus ds fy, ODBC AddressDSN dk iz;ksx djuk pkgrs gSaA bl ODBC Driver dk iz;ksx djds AddressDSN uke ds Database dks Java Front-End ls Connect djus ds fy, gesa fuEukuqlkj Statements fy[kus gksrs gSa% lcls igys JDBC URL Create djuk gksrk gS] tks fd bl fLFkfr esa fuEukuqlkj gksrk gS% String connectionURL = “jdbc:odbc:AddressDSN”;

vc Database ls Connection Establish djus ds fy, gesa Class uke dh Class ds forName() Method dks Call djds vius Operating System dks ;s crkuk gksrk gS fd ge fdl Driver dk iz;ksx djds Front-End ls Databases dks Connect djuk pkgrs gSaA pwafd ge tkok ds “JdbcOdbcDriver” dk iz;ksx djds tkok Front-End ls Data Source dks Connect djuk pkgrs gSa] blfy, gesa tkok Compiler dks fuEukuqlkj Driver Specify djuk gksrk gS% Class.forName(“sun.jdbc.odbc.JdbcOdbcDriver”); Driver Specify djus ds ckn gesa ,d Connection Object Create djuk gksrk gSA fQj Data Source ls Connection LFkkfir djus ds fy, DriverManager ds fy, getConnectoin() Method dks Call djds mlesa JDBC URL Argument ds :i esa Pass djuk gksrk gSA blds fy, gesa fuEukuqlkj Statement fy[kuk gksrk gS% 459 Any Question or Suggestion, Just Discuss Here...

Java in Hindi Connection conDatabase = DriverManager.getConnection(connectionURL);

bu rhuksa Statements dks ge fuEukuqlkj ,d lkFk Specify dj ldrs gSa% String connectionURL = “jdbc:odbc:AddressDSN”; Class.forName(“sun.jdbc.odbc.JdbcOdbcDriver”); Connection conDatabase = DriverManager.getConnection(connectionURL);

Querying A Database

Database ls Connection LFkkfir gks tkus ds ckn ge ml Database esa u, Data dks Store dj ldrs gSa vkSj Database esa Stored fdlh Required Data dks Retrieve dj ldrs gSaA ge tc Database ij dksbZ Query Hkstrs gSa] rks Database ml Query dks Process djrk gS vkSj Generate gksus okys Result dks Return djrk gS] ftls Result Set dgrs gSaA Database ls Query djus ds fy, gesa Database ij SQL Statement Hkstus iMrs gSaA SQL Statements dks Database ij Hkstus ds fy, ge tks SQL Statements fy[krs gSa] mu SQL Statements dks Represent djus ds fy, JDBC gesa rhu rjg dh Classes iznku djrk gSA

ge bu rhu rjg dh Classes ds Objects Create djds fdlh SQL Statement dks Database ij Request ds :i esa Hkst ldrs gSa] ftlds Result ds :i esa Database FrontEnd Client Software dks Result Set Return djrk gSA ;s rhu rjg dh Statement Classes ds Objects fuEukuqlkj gSa% The Statement Object

Statement Object Create djus ds fy, gesa Connection Object ds lkFk createStatement() Method dks Call djuk gksrk gSA

The PreparedStatement Object

PreparedStatement Object Create djus ds fy, gesa Connection Object ds lkFk preparedStatement() Method dks Call djuk gksrk gSA PreparedStatement Object esa Methods dk ,d ,slk lewg gksrk gS] ftudks INPUT Parameters ds lkFk Use djds Queries dks Database ij Hkstk tk ldrk gSA

The CallableStatement Object

CallableStatement Object Create djus ds fy, gesa Connection Object ds lkFk prepareCall() Method dks Call djuk gksrk gSA bl Object esa os Functionalities gksrh gSa] ftudk iz;ksx fdlh Database esa fLFkr “Stored Procedures” dks Call djus ds fy, fd;k tk ldrk gSA ge CallableStatement Object dk iz;ksx djds INPUT o OUTPUT nksuksa Parameters dks leku :i ls Handle dj ldrs gSaA


Java in Hindi Using The Statement Object ge Statement Object dks Use djds Database ij lkekU; Queries dks Process gksus ds fy, Hkst ldrs gSa vkSj Database }kjk Return gksus okys Result Set dks Front-End esa Use dj ldrs gSaA Program // File Name : StatementObjectQueryApp.java import java.sql.*; public class StatementObjectQueryApp { public static void main(String args[]) { try { String connectionURL = "jdbc:odbc:AddressDSN"; Class.forName("sun.jdbc.odbc.JdbcOdbcDriver"); Connection conDatabase = erManager.getConnection(connectionURL); Statement sqlQuery = conDatabase.createStatement(); sqlQuery.executeQuery("SELECT * FROM Contacts");

}

}

} catch(Exception excp) { System.out.println("Error : " + excp); }

tc ge bl Program dks Run djrs gSa] rc gesa Output esa dqN Hkh izkIr ugha gksrk gSA ,slk blfy, gksrk gS] D;ksafd Statement Object dh Query Database ij Run rks gksrh gS] ysfdu Database ls Return gksus okys Result dks Hold djus ds fy, geus dksbZ Object Create ugha fd;k gS] ftlls Return gksus okys Result dks Output esa Display fd;k tk ldsA bl Program esa 1

geus Database ls Connection LFkkfir djus ds fy, JDBC-ODBC Bridge Driver dks Load fd;k gSA 2 getConnection() Method dk iz;ksx djds Connection Object dks Initialize fd;k gSA 3 createStatement() Method dk iz;ksx djds Statement Object Create fd;k gSA vkSj vUr esa 4 executeQyery() Method dk iz;ksx djds Statement Object esa Stored Query dks Execute fd;k gSA The Statement Object Statement Object dk iz;ksx lkekU; izdkj dh Queries dks Database ij Run djus ds fy, fd;k tkrk gSA bl Object ds rhu Methods gksrs gSa] ftudk iz;ksx Database ij Query dks Run djus ds fy, fd;k tk ldrk gSA


Java in Hindi 1 executeQuery() Method ;s Method ,d Simple SELECT Query Execute djrk gS vkSj Database bl Method ds Execute gksus ij ,d Single ResultSet Object Return djrk gSA 2 executeUpdate() Method ;s Method ,d SQL INSERT, UPDATE o DELETE Statement Execute djus esa l{ke gksrk gS 3 execute() Method ;s Method ,d ,slk SQL Statement Execute djrk gS] ftlds dbZ Results Return gks ldrs gSaA The ResultSet Object ResultSet Object gesa ,sls Methods Provide djrk gS] ftudk iz;ksx ge ResultSet Object ds lkFk djds fdlh Table ds Data dks Access dj ikus esa l{ke gksrs gSaA ge tc Hkh Database ij fdlh Statement dks Execute djrs gSa] Database ls ,d ResultSet Return gksrk gSA ResultSet Object Database ls Return gksus okys Data dks ,d Temporary Table ds :i esa Represent djrk gSA blesa ,d Cursor gksrk gS] tks Data ds Current ROW dks Point djrk gSA tc Database ls ResultSet Return gksrk gS] rc Initially ;s Cursor First Row ls igys dh Position ij Placed gksrk gSA

;kuh ;fn First Row dks 0 ekuk tk,] rks Cursor igyh Row ds Record ls igys ;kuh -1 ij Placed jgrk gSA next() Method Cursor dks Record dh vxyh Row ij ys tkrk gSA ge fdlh ResultSet Object ls Data dks izkIr djus ds fy, getXXX() Methods dks Call dj ldrs gSa] tgka XXX Database ls Return gks jgs fdlh Field dk Data Type gksrk gSA vxys Program esa geus fiNys Program dks gh Modify djds mlesa ResultSet Object dks Use fd;k gSA Program // File Name : StatementObjectQueryApp.java import java.sql.*; public class StatementObjectQueryApp { public static void main(String args[]) { ResultSet result; try {

String connectionURL = "jdbc:odbc:AddressDSN"; Class.forName("sun.jdbc.odbc.JdbcOdbcDriver"); Connection conDatabase = DriverManager.getConnection(connectionURL);


Java in Hindi Statement sqlQuery = conDatabase.createStatement(); result = sqlQuery.executeQuery("SELECT * FROM Contacts"); System.out.print("SrNo. \tFName \tLName \tAddress \tCity \tState \tPin \tCountry \n" ); System.out.print("-------------------------------------------------------------------\n" ); while(result.next()) { for(int i=1; i<=8; i++) System.out.print(result.getString(i) + "\t" ); System.out.println(); }

} Output SrNo. 004 001 002 003

}

} catch(Exception excp) { System.out.println("Error : " + excp); }

FName Nand Kuldeep Achyut Govind

LName Nandan Mishra Yadav Gopal

Address Bali Road Nilkanth Road Nilkanth Road Bedal Road

City Rani Falna Falna Bali

State UP RAJ RAJ JPR

Pin 122144 306116 306116 306701

Country India India India India

bl Program esa geus result uke dk ,d ResultSet izdkj dk Object Create fd;k gSA fQj Database ls Connection cukus ds ckn Database ij ,d SQL Query dks Execute fd;k gSA tc ge SQL Statement dks Execute djrs gSa] rc Database ml SQL Query ds vk/kkj ij dqN Records Return djrk gS] ftls result uke ds Object esa Hold fd;k x;k gSA fQj fuEukuqlkj ,d Nested Loop pyk;k x;k gS% while(result.next()) { for(int i=1; i<=8; i++) System.out.print(result.getString(i) + "\t" ); System.out.println(); } while Loop rc rd pyrk gS tc rd fd result uke ds ResultSet Object esa Cursor vfUre Record ij ugha igqap tkrk gSA tSls gh Cursor ResultSet ds vfUre Record ij igqaprk gS] while Loop Terminate gks tkrk gSA ResultSet Object result esa fLFkr fofHkUu Records ds Set esa gj vxys Record ij tkus ds fy, bl Object ds lkFk while Loop esa next() Method dks Call fd;k x;k gSA Loop ds gj Iteration esa Cursor ResultSet ds vxys Record ij igqap tkrk gSA


Java in Hindi bl while Loop ds vUnj ,d for Loop dks pyk;k x;k gSA bl Loop esa geus result uke ds ResultSet izdkj ds Object esa fLFkr fofHkUu Records ds fofHkUu Field ds Data dks Display djus ds fy, getString() Method dks Call fd;k gSA bl Method esa ge Argument ds :i esa tks Number nsrs gSa] tkok gesa ResultSet ds mlh Field dk Data Return dj nsrk gSA pwafd geus igys Hkh dgk gS fd ResultSet Object esa tks Records Database ls Return gksdj vkrs gSa] os Records ,d Table ds leku gksrs gSa vkSj gj Table Records (Rows) dk ,d lewg gksrk gS rFkk gj Record (Row) esa Related Data Items ds NksVs&NksVs fgLls gksrs gSa] ftUgsa Field (Column) dgk tkrk gSA while Loop ,d ckj esa ResultSet esa ,d Record dks Point djrk gSA ml Record esa dbZ Field gksrs gSaA tkok esa gj Field dks mlds Index Number ls Access fd;k tkrk gS vkSj ResultSet ds igys Field dks eku 1 ls nwljs Field dks eku 2 ls o blh rjg ls nlosa Field ds Data dks eku 10 ls Represent fd;k tkrk gSA ekuyks fd gesa Table ds ikapos Field dk Data Return djuk gks rks gesa fuEukuqlkj Statement fy[kuk gksxk% result.getString(5);

pwafd gesa fdlh Record ds lHkh Data Fields dks Return djuk gS lkFk gh Screen ij Print Hkh djuk gS] blfy, geusa bl Statement dks System.out.println() Statement esa Use fd;k gS] lkFk gh bl Statement dks ,d for Loop esa Use fd;k gS vkSj getString() Method esa Argument ds :i esa Loop ds Variable dk eku ns fn;k gSA ,slk djus ij ResultSet Object ds Record ds lHkh Fields ds Data dks Screen ij Print fd;k x;k gSA bl Program esa geus ResultSet ls Return gksus okys Field ds Data dks String Format esa Return djok;k gS] D;ksafd ResultSet ds Data dks gesa Directly Screen ij Print djuk gSA ysfdu ;fn gesa Table ds fdlh Field ds Data ds lkFk dksbZ Calculation djokuh gks rks ge mls fdlh vU; Data Type ds :i esa Hkh Return djok ldrs gSaA mnkgj.k ds fy, ekuyks fd gesa lHkh Serial Numbers esa 1 Add djuk gS vkSj mlds ckn Serial Number dks Print djuk gSA bl fLFkfr esa gesa ResultSet ds izFke Field ds Data dks Integer Format esa Return djokuk gksxk vkSj mlesa 1 Add djus ds ckn mls Print djuk gksxkA bl dke dks iwjk djus ds fy, gesa while Loop dks fuEukuqlkj Modify djuk gksxk% while(result.next()) { for(int i=1; i<8; i++) { if(i==1) System.out.print((result.getInt(1) + 1) + "\t"); System.out.print(result.getString(i+1) + "\t" );

} System.out.println();

tc ge while Loop dks Modify djds Program dks Run djsaxs] rc gesa Output fuEukuqlkj izkIr gksxk%


Java in Hindi Output SrNo. 004 001 002 003

FName Nand Kuldeep Achyut Govind

LName Nandan Mishra Yadav Gopal

Address Bali Road Nilkanth Road Nilkanth Road Bedal Road

City Rani Falna Falna Bali

State UP RAJ RAJ JPR

Pin 122144 306116 306116 306701

Country India India India India

Using PreparedStatement Object tc gesa ,sls Application Develop djus gksrs gSa] ftlesa Run Time esa User dh Requirement ds vk/kkj ij Database ls ResultSet Retrieve djuk gksrk gSA mnkgj.k ds fy, gesa dsoy ml Record dks gh Screen ij Display djuk gS] ftldk SrNo. User Program ds Run Time esa Input djrk gSA bl fLFkfr esa ge fuEukuqlkj SQL Statement fy[krs gSa% SELECT * FROM Contacts WHERE SRNO = ? Database ls bl izdkj dh Query djus ds fy, gesa ,slk Query Statement Create djuk gksrk gS] tks Program ds Run time esa WHERE Clause esa mfpr Parameter izkIr djrk gS vkSj Required Record ResultSet Object esa Return djrk gSA

The PreparedStatement Object ;s Object gesa Parameterized Query Execute djus dh lqfo/kk iznku djrk gSA PreparedStatement Object Create djus ds fy, gesa Connection Object ds lkFk preparedStatement() Method dks Call djuk gksrk gSA ;kuh ;fn ge fiNys Program esa gh Parameterized Parameter dh lqfo/kk izkIr djuk pkgrs] rks gesa SQL Statement Query Object fuEukuqlkj Create djuk gksrk% Statement sqlQuery = conDatabase.preparedStatement( “SELECT * FROM Contacts WHERE SRNO = ?”); Connection Object dk preparedStatement() Method Argument ds :i esa ,d SQL Statement String ysrk gSA bl SQL Statement esa ,slk Placeholder Hkh gks ldrk gS] ftls Program ds Run Time esa fn, x, INPUT }kjk Replace fd;k tk ldrk gSA gekjs bl Statement esa “?” ,d Placeholder gS] ftlds LFkku ij Program ds Run Time esa Parameter INPUT fd;k tk ldrk gSA

Passing INPUT Parameter At Runtime PreparedStatement Object Execute djus ls igys gesa gj “?” Parameter dks dksbZ uk dksbZ eku Set djuk t:jh gksrk gSA bl dke dks setXXX() Method Call djds iwjk fd;k tkrk gS] tcfd XXX Parameter dk Data Type gksrk gSA vxys GUI Program esa Parameter ds vk/kkj ij Record izkIr djus dh Process dks le>k;k x;k gSA Program // File Name : StatementObjectQueryGUIApp.java import java.sql.*;


Java in Hindi import java.awt.*; import java.awt.event.*; public class StatementObjectQueryGUIApp extends Frame{ TextField srno, fname, lname, city, state, pin, cntry; TextArea address; Label lblsrno, lblfname, lbllname, lbladdress; Label lblcity, lblstate, lblpin, lblcntry; Button btnNext; // These variables are declared static because they // have to be used in a static method static ResultSet result; static Connection conDatabase; static PreparedStatement sqlQuery; static StatementObjectQueryGUIApp myWindow ; public StatementObjectQueryGUIApp(){ super("The Runtime parameterized query application"); setLayout(null); srno = new TextField(); fname = new TextField(); lname = new TextField(); address = new TextArea(); city = new TextField(); state = new TextField(); pin = new TextField(); cntry = new TextField(); lblsrno = new Label("Serial Number : "); lblfname = new Label("First Name : "); lbllname = new Label("Last Name : "); lbladdress = new Label("Address : "); lblcity = new Label("City : "); lblstate = new Label("State : "); lblpin = new Label("Pincode: "); lblcntry = new Label("Country : "); btnNext = new Button("Query"); lblsrno.setBounds(20, 40, 100, 20); add(lblsrno); srno.setBounds(120, 40, 100, 22); add(srno); lblfname.setBounds(20, 65, 100, 20); add(lblfname);


Java in Hindi fname.setBounds(120, 65, 250, 22); add(fname); lbllname.setBounds(20, 90, 100, 20); add(lbllname); lname.setBounds(120, 90, 250, 22); add(lname); lbladdress.setBounds(20, 115, 100, 20); add(lbladdress); address.setBounds(120, 115, 250, 70); add(address); lblcity.setBounds(20, 140, 100, 20); add(lblcity); city.setBounds(120, 140, 250, 22); add(city); lblstate.setBounds(20, 165, 100, 20); add(lblstate); state.setBounds(120, 165, 250, 22); add(state); lblpin.setBounds(20, 190, 100, 20); add(lblpin); pin.setBounds(120, 190, 250, 22); add(pin); lblcntry.setBounds(20, 215, 100, 20); add(lblcntry); cntry.setBounds(120, 215, 250, 22); add(cntry); btnNext.setBounds(185, 260, 50, 25); add(btnNext); }

setVisible(true);

public static void main(String args[]){ myWindow = new StatementObjectQueryGUIApp(); myWindow.setSize(400,300); try { String connectionURL = "jdbc:odbc:AddressDSN"; Class.forName("sun.jdbc.odbc.JdbcOdbcDriver"); conDatabase = DriverManager.getConnection(connectionURL); sqlQuery = conDatabase.prepareStatement


Java in Hindi

}

("SELECT * FROM Contacts WHERE ContactID = ? "); }catch(Exception excp){ System.out.println("Error : Hello" + excp); }

public boolean action(Event evnt, Object ObjCaption){ if(evnt.target instanceof Button) HandleButton(ObjCaption); }

return true;

public void HandleButton(Object Caption){ if(Caption == "Query"){ try { sqlQuery.setString(1, srno.getText()); result = sqlQuery.executeQuery(); result.next(); }catch(Exception excp){} showRecord(result); } } // The showRecord method displays a record on the Form Window public void showRecord(ResultSet result){ try { srno.setText(result.getString("ContactID")); fname.setText(result.getString(2)); lname.setText(result.getString(3)); address.setText(result.getString(4)); city.setText(result.getString(5)); state.setText(result.getString(6)); pin.setText(result.getString(7)); cntry.setText(result.getString(8)); }catch(Exception excp) {} } } Output


Java in Hindi

bl Program esa geus ,d Class cukbZ gS] ftlesa ,d Window Develop fd;k gSA bl Window esa geus Database ds fofHkUu Fields ds Data dks Display djus ds fy, dqN Text Fields Create fd, gSa vkSj ,d Query uke dk Button Create fd;k gSA tc ge Serial Number okys Field esa dksbZ Serial Number Input djds Query Button ij Click djrs gSa] rks ml Serial Number okys Record ds lHkh Field Form ij fLFkr fofHkUu Text Boxes esa Fill gks tkrs gSaA bl Program esa geus StatementObjectQueryGUIApp uke dh ,d Class Create dh gS vkSj blds Constructor esa Window Create fd;k gSA fQj blh Class esa ,d main() Method Define fd;k gS vkSj blesa bl Class dk ,d Object Create djds Window dks Screen ij Display fd;k gSA pwafd main() Method ,d Static Method gksrk gS] blfy, bl Method esa Use djus ds fy, geus fuEukuqlkj dqN Objects dks Static izdkj dk Declare fd;k gS% // These variables are declared static because they // have to be used in a static method static ResultSet result; static Connection conDatabase; static PreparedStatement sqlQuery; static StatementObjectQueryGUIApp myWindow;

bl Program esa geus PreparedStatement izdkj dk Object Create fd;k gS] rkfd Program ds Run Time esa User tks Serial Number Input djrk gS] ml Serial Number okyk Record gh Database ls Return gks vkSj ml Record ds fofHkUu Data Field Form ij fLFkr fofHkUu Text Boxes esa Fill gks tk,aA User tks Serial Number Input djrk gS] mlh Serial Number okys Record dks Database ls izkIr djus ds fy, geus fuEukuqlkj Statement Use fd;k gS% sqlQuery = conDatabase.prepareStatement ("SELECT * FROM Contacts WHERE ContactID = ? ");

bl Statement esa ContactID ds ckn ,d Question Mark gS] tks Program ds Run Time esa ContactID Field ds fy, Serial Number ds eku dks srno uke ds Text Field ls izkIr djrk gSA tc ;s Query Run gksrk gS] rc Database ls ogh Record Return gksrk gS] ftldk Serial Number srno Text Field esa gksrk gSA User tc Serial Number Text Field esa dksbZ


Java in Hindi ContactID Input djds Query Button dks Press djrk gS] rks Event Handler esa fuEu Statement Execute gksrk gS% sqlQuery.setString(1, srno.getText());

;s Statement sqlQuery Statement ds igys Question Mark ds LFkku ij srno Text Field ds Text dks Place dj nsrk gSA fQj fuEukuqlkj vxyk Statement Execute gksrk gS vkSj result uke ds ResultSet Object esa Database ls og Record vk tkrk gS] ftldk Serial Number srno uke ds Text Field esa gksrk gSA bl rjg ls ge gekjh Requirement ds vuqlkj okafNr Record dks tkok ds GUI Front-End esa Access dj ldrs gSaA blh rjg ls ge Statement Object esa Argument ds :i esa fdlh Hkh izdkj dh SQL Query dks Database ij Run djok ldrs gSaA mnkgj.k ds fy, ekuyks fd gesa Database esa dksbZ u;k Record Add djuk gks] Database ds fdlh Record dks Delete djuk gks ;k Database ds fdlh Record dks Modify djuk gks] rks ge fuEukuqlkj bu dkeksa dks iwjk djus okys SQL Statement dks Statement Object esa Execute dj ldrs gSa% public void addRecord() { try { sqlQuery.executeUpdate ((“INSERT INTO Contact VALUES(“005”, “Manohar”,” ... “”)”); } catch(Exception excp) {} } public void modifyRecord() { try { sqlQuery.executeUpdate (“UPDATE Contact SET ContactID = “005”, FName = “Mohan”,” ... “”); } catch(Exception excp) {} } public void deleteRecord() { try { sqlQuery.executeUpdate (“DELETE Contact WHERE ContactID = “005” ”); } catch(Exception excp) {} }


Java in Hindi

Java AWT Abstract Windowing Toolkit


Java in Hindi Java AWT – Abstract Windowing Toolkit Event Driven Programming System

ekuyks fd ge lqcg&lqcg tSls gh Office tkus ds fy, ?kj ls ckgj fudyus okys gksrs gh gSa fd rqjUr Phone dh ?k.Vh ctus yxrh gSA Phone dh ?k.Vh dk ctuk ,d izdkj dk Event gSA Real Life esa dbZ ckj ,sls Events gksrs gSa] ftUgsa ckdh lHkh dkeksa dks Suspend djds rqjUr Respond djuk iMrk gSA mnkgj.k ns[ksa rks ge pkgs ftruh Hkh tYnh esa gksa] ysfdu vxj Phone dh ?k.Vh ctrh gS] rks gesa ml Phone dks Attend djuk gh iMrk gSA blh Concept dks tc ge Programming ds lUnHkZ esa ns[krs gSa] rc fdlh Program o mlds User ds chp ftruh Hkh Activities gksrh gSa] mu lHkh Activities dks tkok esa Events dgk tkrk gSA User Keyboard ls dksbZ Key Press djrk gS ;k Mouse ls Application ds fdlh Command Button ij Click djrk gS ;k Application Program ds Window dks Resize djrk gS] Software ;k Hardware dk Fail gksuk] fdlh List esa ls fdlh Item dks Select djuk] Timer ds Counter dk Increment gksuk vkfn fofHkUu izdkj ds Events gSaA tc User fdlh Program ds lkFk Interaction djrk gS] rc Computer ,d Event Object Create djrk gSA ;s Event Object ml Action dks Represent djrk gS] ftls User us Perform fd;k gSA ;kuh ekuyks fd User us fdlh Application ds fdlh Button ij Click fd;k] rks Computer ,d Object Create djsxk vkSj ml Object }kjk Click Event Represent gksxkA fQj ge bl Click Event dks ,d Event Handler Coding }kjk Handle dj ldrs gSa vkSj og dke djokrs gSa] tks Click Event ds Generate gksus ij djokuk gksrk gSA ;s Event Handler Code gh ;s r; djrk gS fd fdlh Event dks fdl izdkj ls Handle djuk gSA fdlh Event dks fofHkUu izdkj ls Drive djds Program Develop djus o mls Handle djus dh rduhd dks Event Driven Programming dgrs gSa] ftlesa fofHkUu izdkj dh Events dks Response djus okys Code Handlers fy[k dj Programming ;k Development fd;k tkrk gSA tkok ,d Pure Object Oriented Programming Language gS] blfy, ge bl Language esa fdlh Hkh pht dks ,d Object ds :i esa Represent djrs gSaA blhfy, User }kjk fdlh Hardware dks Access djus ls dksbZ Event Generate gks ;k fdlh Software }kjk dksbZ Event Generate gks] nksuksa gh fLFkfr;ksa esa fdlh Event dks Represent djus ds fy, ,d Event Object Create gksrk gSA GUI Programming esa Event Handle djuk lcls t:jh dke gksrk gSA GUI Program ;k Event Driven Programming Modal esa gekjk GUI Program User ds fdlh Hkh Action dk bUrtkj djrk jgrk gSA tc User ml Application ds lkFk fdlh izdkj dk Interaction djrk gS] rks ml Interaction ls lEcaf/kr dksbZ uk dksbZ Event Generate gksrk gS vkSj ml Event dks Handle djus ds fy, dksbZ uk dksbZ Handler fy[kk x;k gksrk gS] tks fd Event ds Response esa Execute gks tkrk gSA GUI dh lcls cMh fo”ks’krk ;s gS fd fdlh GUI Application ds Operations ds Perform gksus ds Øe dks User fu/kkZfjr djrk gS] ;kuh og fdlh Application ij fn[kkbZ ns jgs fdlh Hkh 472 Any Question or Suggestion, Just Discuss Here...

Java in Hindi Button dks ;k fdlh Hkh vU; Control dks fdlh Hkh le; Use dj ldrk gS] tcfd CUI Applications esa Program ds Execution dk Sequence Programmer r; djrk gS vkSj User dks mlh izdkj ls pyuk iMrk gS ftl rjg ls Programmer us Program dks fy[k dj r; fd;k gSA Event Driven Program fuEukuqlkj Execute gksrs gSa% Algorithm of GUI Application 1 START 2 CREATE GUI OBJECT 3 LISTEN EVENT 4 IF EVENT = CLOSE APPLICATION EXIT ELSE PROCESS EVENT 5 GOTO STEP 3

[Starting the Window Based GUI Application] [Create a GUI Application Object like A Window] [Listen for an Event Occurred by the Interaction ] [If Occurred Event is for closing the Application ]

[Go to the Step 4 again and get next Event ]

Flow of GUI Application START

Create a GUI Interface Object – A Window

Listen for an Event

Is Event = Close Window

Yes

No Process the Event

Components of an Event

tkok esa fdlh Hkh Event dks rhu fgLlksa esa caVk gqvk ekuk tk ldrk gS%


END

Java in Hindi Event Object tc User Keyboard ds fdlh Button dks Press djds ;k Mouse ds fdlh Button dks Click djds fdlh Application ls Interact djrk gS] rc ,d Event Generate gksrk gSA Event Driven Architecture ij vk/kkfjr Operating System bl Event o Event ls Related t:jh Data dks Trap dj ysrk gSA mnkgj.k ds fy, User fdlh Application ds Window ij Click djrk gS] rc User us fdl Button ls Click fd;k gS vkSj fdl x, y Location ij Click fd;k gS] bl ckr dh tkudkjh Data ds :i esa mlh Application ds mlh Object dks okil Hkst nsrk gS] ftl Object ij Click djus ij Event Generate gqvk gksrk gSA tkok esa gj Event dks ,d Object }kjk Represent fd;k tkrk gS vkSj og Object Generate gksus okys Event ls lEcaf/kr fofHkUu tkudkfj;ksa dks Hold djds j[krk gSA Event Object ds fdlh Data Member ds eku esa ifjorZu gksus dk eryc gS fd dksbZ Event Generate gqvk gSA ;k fQj ge ,slk Hkh dg ldrs gSa fd fdlh Event Object ds fdlh Data Member ds eku esa ifjorZu gksus dks gh ge Indirectly Event Generate gksuk dg ldrs gSaA tkok esa fofHkUu izdkj ds Events dks Describe o Handle djus ds fy, dbZ Classes igys ls gh Develop djds Library ds :i esa iznku dj nh xbZ gSaA Event Source

Event Source ,d ,slk Object gS] tks Event Generate djus esa l{ke gksrk gS ;k Event Generate djrk gSA fofHkUu izdkj ds GUI User Interface Components dks ge Source Objects dg ldrs gSaA mnkgj.k ds fy, Button, TextField, List Box, Menu Item vkfn os User Interface Source Objects gSa] tks Event Generate djus esa l{ke gksrs gSaA Event rc Generate gksrk gS] tc fdlh rjhds ls fdlh Event Object dh Internal State ;kuh fdlh Event Class ds fdlh Object ds fdlh Data Member dh fLFkfr esa dksbZ ifjorZu gksrk gSA dksbZ Event Source ,d ls vf/kd izdkj dh Events dks Hkh Generate

dj ldrk gSA

fdlh Object }kjk tc fdlh izdkj dh dksbZ Event Generate gksrh gS] rks ml Event dks Handle djus ds fy, Object dks ,d Listener ls Associate djuk iMrk gSA bl izfØ;k dks Event dks Listener ls Register djuk dgk tkrk gSA Listener ,d Class gksrh gS] ftlds Object esa fdlh Event Generate djus okys Object }kjk Generate gksus okys Events dks Handle djus ds fy, Object ds Interface ls lEcaf/kr fofHkUu izdkj ds Event Methods dks Implement fd;k tkrk gSA

gj Event dk Listener ds lkFk Registration dk viuk ,d vyx rjhdk gksrk gSA fdlh Hkh Event Generate djus okys Object dk mlds Listener ds lkFk Registration dk General Syntax fuEukuqlkj gksrk gS% public void addTypeListener(TypeListener listenerObject)


Java in Hindi ;gka Type Generate gksus okys Event dk uke gksrk gS vkSj listenerObject Event dks Listen djus okys Event Listener Object dk Reference gksrk gSA mnkgj.k ds fy, og Method tks fd Keyboard Event Listener ls Register gksrk gS] addKeyListener() Method dgykrk gSA og Method tks fd Mouse Motion Listener ls Register gksrk gS] addMouseMotionListener() Method dgykrk gSA tc dksbZ Event Generate gksrk gS] rks Program ds lHkh Registered Listeners Notify gksrs gSa] ;k lHkh Registered Listeners Generate gksus okys Event dks Listen djrs gSa ;k lqurs gSa vkSj Generate gksus okys Event Object dh ,d Copy izkIr djrs gSaA bl izfØ;k dks Event dh Multicasting gksuk dgrs gSaA lHkh fLFkfr;ksa esa Notifications dsoy mUgha Listeners ij Hksts tkrs gSa] ftUgsa Event dks Listen djus ds fy, Register fd;k x;k gksrk gSA dqN Event Generator Source Objects dsoy ,d Listener ls Register gksuk Allow djrs gSaA bl izdkj ds Methods dh General Form fuEukuqlkj gksrh gS% public void addTypeListener(TypeListener listenerObject)] throws java.util.TooManyListenersException

tc bl izdkj dh fLFkfr gksrh gS] ftlesa ,d Source dsoy ,d gh Listener ij Notify gksrk gS] rks bl izfØ;k dks Event dh Unicasting gksuk dgrs gSaA ge fdlh Source Object dks fdlh Listener ls Unregistered Hkh dj ldrs gSaA tc gesa fdlh Source Object dks fdlh Listener ls Unregistered djuk gksrk gS] rkfd og Listener ml Source Object ls Generate gksus okys Event ls Notify uk gks] rc gesa fuEukuqlkj Method Use djuk gksrk gS% public void removeTypeListener(TypeListener listenerObject)

os Methods tks fd Listeners dks Add ;k Remove djrs gSa] Event Generate djus okys Source Object }kjk iznku fd, tkrs gSaA mnkgj.k ds fy, Keyboard o Mouse ls Event Listener Add djus ds fy, Component Class ls Methods izkIr gksrs gSaA Event Handler

Event – Handler ,d Method gksrk gS tks Generate gksus okyh Event dks le>rk gS vkSj mls Process djus esa l{ke gksrk gSA Event Handler Method ,d Event izdkj ds Object dks Parameter ds :i esa ysrk gSA

Event Handling Mechanism – Double Approach The JDK 1.02 Event Model tkok esa fdlh Event dks Handle djus ds nks Model iz;ksx esa fy, tkrs gSaA igyk Model JDK 1.02 ds fy, Develop fd;k x;k Fkk tcfd nwljk Model JDK 1.2 ds fy, Develop fd;k x;k FkkA nwljs rjhds dks “Delegation Model” Hkh dgrs gSaA


Java in Hindi igys Model esa Windows ds lHkh Events dh Processing dks ,d Event Class esa Encapsulate fd;k x;k FkkA blesa Program }kjk Handle fd, tkus okys fofHkUu Events dks Represent djus okyh “Events ds Constants” dh ,d List FkhA bu Constants dk iz;ksx Generate gksus okys Event ds Type dks Identify djus ds fy, fd;k tkrk FkkA ;s irk yxkus ds fy, fd Event Generate gksrs le; User us Ctrl, Alt ;k Shift tSlh Special Keys dks Press dj j[kk Fkk ;k ugha] bl Event Class esa dqN Methods Hkh FksA ge bu Methods ls ;s irk yxk ldrs Fks fd Mouse ds fdl Button dk iz;ksx djus ij Event Generate gqvk FkkA JDK 1.02 esa Events dks Handle djus ds fy, ftl Model dk iz;ksx fd;k tkrk Fkk] og Model Inheritance Model ij vk/kkfjr FkkA bl Model esa gesa fofHkUu izdkj ds Window Components dks ,d Sub Class esa Inherit djus ds ckn bl Class ds Action() o handleEvent() Method dks Override djuk iMrk FkkA

bu Methods }kjk ;fn True Return gksrk Fkk rks bldk eryc Fkk fd Event Bhd rjhds ls Handle gks x;k gS] tcfd ;fn bu Methods ls False Return gksrk Fkk] rks bldk eryc gksrk Fkk fd Event Bhd rjg ls Handle ugha gks ik;k gS vkSj mls iwjh rjg ls Handle gksus ds fy, vkSj Processing dh t:jr gSA ;fn Method False Return djrk Fkk rks Event Component ds Container esa Pass gks tkrk FkkA Container ds ckjs esa ge vkxs le>saxsA bl rjhds ls Events dks Handle djus dh lcls cMh deh ;s Fkh fd fdlh Event dks ml Component }kjk Hkh Handle fd;k tk ldrk Fkk] tks fd Event ;k mlds Container ls Initiated gksrs FksA ,slk gksus ls Object Oriented Programming Concept ds ml fu;e dk mYya?ku gksrk Fkk] ftlesa fdlh Object dh Functionality mldh Class esa gh fLFkr gksrh gSA bl rjhds dh nwljh deh ;s Fkh fd blesa Containment Hierarchy }kjk Unimportant Events dks Hkstus ls CPU Cycles Waste gksrs FksA bl Model esa dksbZ Hkh ,slk rjhdk ugha Fkk ftlls Unimportant Events dks Ignore fd;k tk ldrk gksA bu dfe;ksa ls NqVdkjk ikus ds fy, JDK 1.1 esa “Delegation Event Model” dks Develop fd;k x;kA

Delegation Event Handling Model bl Model esa ge mu Objects dks Specify dj ldrs gSa] ftUgsa fdlh Event ds Generate gksus ij Notify fd;k tk lds fd Generate gksus okyk Event fdl Object ds fy, gSA ;fn Generate gksus okyk Event fdlh Hkh Object ls lEcaf/kr uk gks] rks og Event Discard gks tkrk gSA JDK 1.2 dk Model ;kuh Delegation Event Model eq[;r% pkj Components ij vk/kkfjr gksrk gS% 1 2 3

4

Event Classes Event Listeners Explicit Event Handling Adapters


Java in Hindi Event Classes

Event Class Hierarchy esa EventObject Class lcls igyh ;k Top dh Class gksrh gSA ;s Class java.util Package ls Related Class gSA Event ls lEcaf/kr T;knkrj vU; Classes java.awt.event Package ls Related Class gksrh gSaA java.util.EventObject Class o java.awt.AWTEvent Class java.awt.event Package ls lEcaf/kr Classes ugha gSaA JDK 1.2 dh Event Class dh Hierarchy dks ge fuEukuqlkj n”kkZ ldrs gSa%

os Classes tks Events dks Represent djrh gSa] tkok ds Event Handling Mechanism dh Fundamental Classes gSaA EventObject tkok ds Event Classes dh Hierarchy dh Top Level Class gS] ftls java.util Package esa Define fd;k x;k gSA ;s lHkh Event Classes dh Super Class gSA bldk ,d Constructor fuEukuqlkj gS% EventObject(Object src);

bl Constructor esa src og Object gS] tks Event Generate djrk gSA EventObject Class esa getSource() o getID() uke ds nks Methods gSaA EventObject Class dk getSource() Method ml Object dks Return djrk gS] ftlus Event dks Generate fd;k gksrk gSA bl Method dk General Form fuEukuqlkj gksrk gS% Object getSource()

pwafd toString() Method Generate gksus okys Event dk String Representation Return djrk gSA blfy, ge bl Method dks Use djds ml Object dk uke izkIr dj ldrs gSa] ftlus Event Generate fd;k gksrk gS ;k fQj ge viuh t:jr ds vuqlkj fdlh Event dh Type Casting djds mls vyx rjhds ls Hkh Use dj ldrs gSaA java.awt Package esa AWTEvent uke dh ,d Sub Class dks Define fd;k x;k gS] tks fd EventObject Class dh ,d Sub Class gSA ;s Class Delegation Event Model esa (Directly ;k Indirectly) Use dh tkus okyh lHkh AWT – Based Event Classes dh Super Class gksrh gSA EventObject Class dk getID() Method ml Event ID dks Return djrk gS] tks Event dh izd`fr dks fu/kkZfjr djrk gSA bl Method dk General Form fuEukuqlkj gksrk

gS%

int getID() 477 Any Question or Suggestion, Just Discuss Here...

Java in Hindi ekuyks ;fn ,d Mouse Event Generate gksrk gS] rks ge bl Method dks Use djds ;s irk yxk ldrs gSa fd fdl Class ds Object ls Event Generate gqvk gSA ;kuh Event Object ls Click Event Generate gqvk gS ;k Drag Event Generate gqvk gS ;k Move Event Generate gqvk gS ;k Mouse Button dks Release fd;k x;k gSA tSlkfd ge fiNys fp= esa ns[k ldrs gSa] fd ftruh Hkh Event Classes gSa] mu lHkh Event Classes dks AWTEvent Class ls Derive fd;k x;k gSA ;kuh ;fn lkjka”k esa dgsa rks EventObject Class lHkh Event dh Super Class gS vkSj AWTEvent lHkh AWTEvent Class lHkh AWT Event Classes dh Super Class gS] ftUgsa Delegation Event Model esa Use fd;k tkrk gSA java.awt.event Package esa fofHkUu izdkj ds Events dks Handle djus dh Classes dks Define fd;k x;k gSA fdl fLFkfr esa dkSulk Event Generate gksrk gS] bldh tkudkjh gesa

fuEu fcUnqvksa ls izkIr gks ldrh gS%

• tc dksbZ Component Activate gksrk gS] dksbZ Button Press gksrk gS] dksbZ List Item Double Clicked gksrk gS ;k fdlh Menu Item dks Select fd;k tkrk gS] rc ActionEvent Object Generate gksrk gSA • tc Scrollbar ;k fdlh Adjustable Element dks Use fd;k tkrk gS] rc AdjustmentEvent Generate gksrk gSA • tc dksbZ Component Hide, Visible, Move ;k Resize fd;k tkrk gS] rc ComponentEvent Generate gksrk gSA • tc fdlh Container esa dksbZ Object Add fd;k tkrk gS ;k fdlh Container ls fdlh Object dks Delete fd;k tkrk gS] rc ContainerEvent Object Generate gksrk gSA • tc dksbZ Component Input ds fy, Focus Receive djrk gS ;k tc fdlh Component ls Focus fdlh nwljs Component ij Move gksrk gS] rc FocusEvent Object Generate gksrk gSA • lHkh Input Component dh Input Classes dh InputEvent Class Super Class gSA blfy, fdlh Hkh Input Object esa Input djus ij ;s Event Generate gksrk gSA • tc fdlh List Box, Choice Box ;k Check Box ls fdlh Item dks Select fd;k tkrk gS] rc ItemEvent Object Generate gksrk gSA • tc Keyboard ls fdlh Key dks Press djds Input izkIr fd;k tkrk gS] rc KeyEvent Object Generate gksrk gSA • tc fdlh Window ls lEcaf/kr Activities tSls fd Window dks Activate, Close, Deactivate, Deiconified, Iconified, Open, Restore, Minimize ;k Maximize vkfn djus ij WindowEvent Object Generate gksrk gSA • tc Mouse dks Click, Press, Release, Drag, ;k Move fd;k tkrk gS] rc MouseEvent Object Generate gksrk gSA • tc dksbZ Component Paint gksrk gS] rc PaintEvent Object Generate gksrk gSA • tc fdlh Text Component ds Text dks Modify fd;k tkrk gS] rc TextEvent Object Generate gksrk gSA • tc Mouse ds Scroll Wheel dks Move fd;k tkrk gS] rc MouseWheelEvent Generate gksrk gSA ;s Event dsoy tkok ds 1.4 o blds ckn ds Version esa gh miyC/k gSA


Java in Hindi Event Listeners

Delegation Event Model dks eq[;r;k nks Hkkxksa Source o Listeners esa foHkkftr fd;k x;k gSA fdlh Event dks Generate djus okys fofHkUu izdkj ds Source Objects dks Create djus okyh Classes dks java.awt Package esa Define fd;k x;k gS] tcfd tkok ds java.awt.event Package esa Define fd, x, ,d ;k ,d ls vf/kd Interfaces dks Implement djds Listeners Objects dks Create fd;k tkrk gSA Event Listener ,d ,slk Object gksrk gS tks fdlh Event ds Generate gksus ij Notify gksrk gSA tc dksbZ Event Generate gksrk gS] rc Event Generate djus okyk Source Object Listener esa Define fd, x, fdlh Appropriate Method dks Invoke djrk gS vkSj ml Method esa Argument ds :i esa ,d Event Object iznku djrk gSA fdlh Hkh Event Listener dh eq[;r% nks Requirement gksrh gSa%

1 bls ,d ;k ,d ls vf/kd Source Objects ds lkFk Register fd;k tk,] rkfd ;s mu Source Objects }kjk Generate gksus okys Events ls Notify gks lds vkSj 2 bu Notifications dks izkIr djds mUgsa Process djus ds fy, Methods Implement fd, tk,aA os Methods tks Source Objects ls Generate gksus okys Events dks Receive o Process djrs gSa] Interfaces ds ,d lewg ds :i esa java.awt.event uke ds Package esa Specify fd, x, gSaA mnkgj.k ds fy, MouseMotionListener Interface esa Mouse Move gksus ds Notifications dks Receive djus ds fy, nks Methods Define fd, x, gS vkSj ;s nksuksa Methods rc Notification izkIr djrs gSa tc Mouse dks Drag ;k Move fd;k tkrk gSA Mouse dks Drag ;k Move djus ij Mouse Move Event Generate gksrk gS vkSj bl Event dks Handle djus ds fy, gesa MouseMotionListener Interface ds nksuksa Methods dks Implement djuk gksrk gSA ;fn fdlh Class esa bl Interface dks Implement fd;k x;k gks] rks ml Class dk dksbZ Hkh Object bu nksuksa esa ls fdlh ,d ;k nksuksa Events dks Receive djrs gq, Notify gks ldrk gSA fofHkUu izdkj ds Events dks Handle djus ds fy, Common :i ls Use fd, tkus okys Interfaces o muesa Define fd, tkus okys Methods dks ge fuEu Description ls le> ldrs gSa%

ActionListener Interface bl Interface esa actionPerformed() uke dk ,d Method Define fd;k tkrk gS] tks fd Argument ds :i esa fdlh ActionEvent Object dks Receive djrk gSA ;s Method rc Invoke gksrk gS] tc dksbZ ActionEvent Object Generate gksrk gS vkSj ;s Object rc Generate gksrk gS] tc fdlh Command Button ij Click fd;k tkrk gS] ;k fdlh Menu Item dks Select fd;k tkrk gS ;k fQj fdlh List Item dks Double Click fd;k tkrk gSA bl Method dk Syntax fuEukuqlkj gksrk gS% void actionPerformed(ActionEvent actnEvnt)


Java in Hindi AdjustmentListener Interface bl Interface esa adjustmentValueChanged() uke ds ,d Method dks Define fd;k tkrk gS] tks Argument ds :i esa fdlh AdjustmentEvent Object dks Receive djrk gSA ;s Method rc Invoke gksrk gS tc dksbZ Adjustment Event Generate gksrk gSA bl Method dk General Syntax fuEukuqlkj gksrk gS% void adjustmentValueChanged (AdjustmentEvent adjEvnt)

ComponentListener Interface bl Interface esa pkj Method dks Define fd;k tkrk gS] tks fdlh Component dh Hidden, Moved, Resized ;k Visible fLFkfr dks Identify djrs gq, Execute gksrs gSaA bu Methods dk General Syntax fuEukuqlkj gksrk gS% void componentResized(ComponentEvent compEvnt) void componentMoved(ComponentEvent compEvnt) void componentShown(ComponentEvent compEvnt) void componentHidden(ComponentEvent compEvnt)

ContainerListener Interface bl Interface esa nks Method dks Define fd;k tkrk gS] tks Container esa fdlh Component Add gksus ;k Container ls fdlh Component ds Remove gksus dh fLFkfr dks Identify djrs gq, Execute gksrs gSaA ;kuh tc fdlh Container esa dksbZ Component Add fd;k tkrk gS] rc componentAdded() Method Execute gksrk gS vkSj tc fdlh Container ls dksbZ Component Remove fd;k tkrk gS] rc componentRemoved() Method Execute gks tkrk gSA bu Methods dk General Syntax fuEukuqlkj gksrk gS% void componentAdded(ContainerEvent contEvnt) void componentRemoved(ContainerEvent contEvnt)

FocusListener Interface bl Interface esa nks Method dks Define fd;k tkrk gSA ;s Methods fdlh Component ds Keyboard Focus Receive djrs le; o Focus dks Lost djrs le; Execute gksrs gSa] ;kuh tc dksbZ Component Keyboard dk Focus Receive djrk gS] rc focusGained() Method Execute gksrk gS vkSj tc dksbZ Component Keyboard ds Focus dks Lost djrk gS] rc focusLost() Method Execute gksrk gSA bu Methods dk General Syntax fuEukuqlkj gksrk gS% void focusGained(FocusEvent focusEvnt) void focusLost(FocusEvent focusEvnt)


Java in Hindi ItemListener Interface bl Interface esa ,d Method dks Define fd;k tkrk gS] tks fdlh Component dh ml fLFkfr dks Identify djrk gS] tc Component ds fdlh Item dks Change fd;k tkrk gSA ;kuh fdlh Component ds fdlh Item dks Change djus ij bl Listener esa Define fd;k x;k itemState() uke dk Method Execute gks tkrk gSA bl Method dk General Syntax fuEukuqlkj gksrk gS% void itemState(ItemEvent itmEvnt)

KeyListener Interface bl Interface esa rhu Method dks Define fd;k tkrk gS vkSj ;s rhuksa Method rc Execute gksrs gSa] tc fdlh Keyboard ls dksbZ Key Press fd;k tkrk gSA tc dksbZ Key Press fd;k tkrk gS] rc keyPressed() Method Execute gksrk gSA tc Key dks Release fd;k tkrk gS] rc keyReleased() Method Invoke gksrk gS vkSj tc Keyboard ls dksbZ Key Type fd;k tkrk gS] rc keyTyped() Method Invoke gksrk gSA mnkgj.k ds fy, tc Keyboard ls dksbZ Key Press fd;k tkrk gS] rc Key Pressed, Key Typed o Key Released Events ds Øe esa rhu Events Generate gksrs gSaA ;fn User HOME Key dks Press djds Release djrk gS] rks dsoy nks Events Key Pressed o Key Released ds Øe esa Generate gksrs gSaA bl Interface ds rhuksa Methods dk General Syntax fuEukuqlkj gksrk gS% void keyPressed(KeyEvent keyEvnt) void keyReleased(KeyEvent keyEvnt) void keyTyped(KeyEvent keyEvnt)

MouseListener Interface bl Interface esa ikap Methods dks Define fd;k tkrk gS] tks Mouse ds fdlh Component ij Click gksus] Component esa Enter gksus] Component ls Exit gksus] Component ds Press gksus vkSj Component ds Release gksus dks Identify djrs gSaA ;kuh 1 tc User Mouse ds fdlh Button dks fdlh Point ij Press djds mlh Point ij Release dj nsrk gS] rks mouseClicked() Method Invoke gksrk gSA 2 tc Mouse Pointer fdlh Component ij Enter gksrk gS] rc mouseEntered() Method Invoke gksrk gSA 3 tc Mouse Pointer fdlh Component ls Exit gksrk gS] rc mouseExited() Method Invoke gksrk gSA 4 tc Mouse ds fdlh Button dks Press fd;k tkrk gS] rc mousePressed() Method Invoke gksrk gSA 5 tc Mouse ds fdlh Button dks Release fd;k tkrk gS] rc mousePressed() Method Invoke gksrk gSA 481 Any Question or Suggestion, Just Discuss Here...

Java in Hindi bu Methods dk General Syntax fuEukuqlkj gksrk gS% void mouseClicked(MouseEvent mousEvnt) void mouseEntered(MouseEvent mousEvnt) void mouseExited(MouseEvent mousEvnt) void mousePressed(MouseEvent mousEvnt) void mouseReleased(MouseEvent mousEvnt)

MouseMotionListener Interface bl Interface esa nks Method dks Define fd;k tkrk gSA tc Mouse dks Drag fd;k tkrk gS rc mouseDragged() Method Invoke gksrk gS vkSj tc Mouse dks Move fd;k tkrk gS] rc mouseMoved() Method Invoke gksrk gSA bu nksuksa Methods dk General Syntax fuEukuqlkj gksrk gS% void mouseDragged(MouseEvent mousEvnt) void mouseMoved(MouseEvent mousEvnt)

MouseWheelListener Interface bl Interface esa ,d Method Define fd;k tkrk gS] tks rc Invoke gksrk gS] tc Mouse ds Wheel dks ?kqek;k ;k Move fd;k tkrk gSA bl Method dk General Form fuEukuqlkj gksrk gS% void mouseWheelMoved(MouseEvent mousEvnt)

TextListener Interface bl Interface esa ,d Method Define fd;k tkrk gSA tc fdlh TextField ;k TextArea Object esa Text dks Change fd;k tkrk gS] rc textChanged() Method Invoke gksrk gSA bl Method dk General Syntax fuEukuqlkj gksrk gS% void textChanged(TextEvent txtEvnt)

WindowFocusListener Interface bl Interface esa windowGainedFocus() o windowLostFocus() Methods dks Define fd;k tkrk gS] tks Øe”k% Window ds Focus izkIr djus o Lost djus ij Execute gksrs gSaA budk General Syntax fuEukuqlkj gksrk gS% void windowGainedFocus(WindowEvent wndEvnt) void windowLostFocus(WindowEvent wndEvnt)


Java in Hindi WindowListener Interface bl Interface esa lkr Methods Define fd, tkrs gSa] tks Window ds Activate gksus] Close gksus] Deactivate gksus] Deiconified gksus] Open gksus] Iconified gksus o Quit gksus ij Execute gksrs gSaA 1 tc dksbZ gSA 2 tc dksbZ gksrk gSA 3 tc dksbZ gSA 4 tc dksbZ gksrk gSA 5 tc dksbZ 6 tc dksbZ 7 tc dksbZ gksrk gSA

Window Activate gksrk gS] rc windowActivated() Method Invoke gksrk Window Deactivate gksrk gS] rc windowDeactivated() Method Invoke Window Iconified gksrk gS] rc windowIconified() Method Invoke gksrk Window Deiconified gksrk gS] rc windowDeiconified() Method Invoke Window Open gksrk gS] rc windowOpend() Method Invoke gksrk gSA Window Close gksrk gS] rc windowClosed() Method Invoke gksrk gSA Window Close gks jgk gksrk gS] rc windowClosing() Method Invoke

bu lHkh Methods ds General Syntax fuEukuqlkj gksrs gSa% void windowActivated(WindowEvent wndEvnt) void windowDeactivated(WindowEvent wndEvnt) void windowIconified(WindowEvent wndEvnt) void windowDeiconified(WindowEvent wndEvnt) void windowOpend(WindowEvent wndEvnt) void windowClosed(WindowEvent wndEvnt) void windowClosing(WindowEvent wndEvnt)

Using The Delegation Event Model - Handling An Event

fofHkUu izdkj ds Event dks Represent djus okyh Classes o fofHkUu izdkj ds Events dks Handle djus ds fy, Implement fd, tkus okys Interfaces dh Basic tkudkjh izkIr djus ds ckn vc ge bUgsa Practically Use djuk lh[ksaxsA Delegation Event Model esa tc dksbZ Object fdlh Event dks Generate djrk gS] rks ml Event dks Handle djus ds fy, gesa ,d Event Listener Class Create djuk gksrk gSA ;s Event Listener Class ml Object ls Generate gksus okys Events dks Handle djus ds fy, fofHkUu izdkj ds Interfaces dks Implement djrk gSA ftl Object ls Generate gksus okys Events dks Handle djus ds fy, ge tks Listener Class Develop djrs gSa] ml Listener Class ls Source Object dks Register fd;k tkrk gSA

;kuh Listener dks ;s crk;k Response djsxk ;k fdl Component ls Generate ls T;knk Listener gks ldrs

tkrk gS fd og fdl Object ls Generate gksus okys Events dks Object ls Generate gksus okys Events ls Notify gksxkA ,d gksus okys fofHkUu izdkj ds Events dks Handle djus ds fy, ,d gSaA


Java in Hindi tkok esa fofHkUu izdkj ds GUI Component Objects fofHkUu izdkj ds Events ls Associated gksrs gSaA mnkgj.k ds fy, tc User fdlh Command Button dks Press djrk gS] rks Command Button ls Associated Click Event Object Generate gksrk gSA dksbZ Listener Object rHkh fdlh Component ls Associated Event dks Listen ;k Hear djrk gS ;k lqurk gS] tc igys ml Listener Object dks Component ds lkFk Register fd;k x;k gksrk gSA mnkgj.k ds fy, ;fn fdlh MouseListener Object mouseListener dks fdlh Button Component Object myButton ls Generate gksus okys Event Object dks Hear djuk gks] rks igys mouseListener Object ds lkFk myButton Component dks Register djuk gksrk gSA fdlh Component dks MouseListener Object mouseListener ds lkFk Register djus ds fy, gesa fuEukuqlkj Statement Use djuk gksrk gS% myButton.addMouseListener(mouseLister);

The ActionEvent Class ,d ActionEvent rc Generate gksrk gS] tc User fdlh Command Button dks Press djrk gS] ;k fdlh List Item dks Double Click djrk gS ;k fQj tc fdlh Menu Item dks Select djrk gSA ActionEvent Class esa pkj Integer Constants (ALT_MASK, SHIFT_MASK, CTRL_MAST, META_MASK) dks Define fd;k x;k gS] ftudk iz;ksx fdlh Action Event ds lkFk Use fd, x, fdlh Modifier dks Represent djus ds fy, fd;k tkrk gSA bu Constants ds vykok bl Class esa ACTION_PERFORMED uke dk ,d vkSj Integer Constant gksrk gS] ftldk iz;ksx fdlh Action Event dks Identify djus ds fy, fd;k tk ldrk gSA ActionEvent Class ds rhu Constructors fuEukuqlkj gSa% ActinoEvent(Object src, int type, String cmd) ActinoEvent(Object src, int type, String cmd, int modifiers) ActinoEvent(Object src, int type, String cmd, long when, int modifiers) src

;s Argument ml Object dks Represent djrk gS] ftlus Event Generate fd;k gksrk gSA

type

;s Argument Represent gksus okys Event ds Type dks Represent djrk gSA

cmd

;s Argument ml Object ds uke dks Represent djrk gS] ftlus Event Generate fd;k gksrk gSA

modifiers

tc ge fdlh CTRL, SHIFT, ALT, META Keys ;k buds Key Combination dks Use djds bl Event dks Generate djrs gSa] ;kuh fdlh List Item ij Double Click djrs gSa ;k fdlh Menu Item dks Select djrs gSa] rc bl modifier esa ml Special Key ;k Key Combination dh Information gksrh gSA


Java in Hindi ftl Command es ActionEvent Generate fd;k x;k gksrk gS] ml Command dk uke ge getActionCommand() Method dks Use djds izkIr dj ldrs gSaA bl Method dk Syntax fuEukuqlkj gksrk gS% String getActionCommand()

mnkgj.k ds fy, tc fdlh Button dks Press fd;k tkrk gS] rc ,d ActionEvent Generate gksrk gS vkSj ml Command dk uke tks fd ml Command Button ij fn[kkbZ nsus okyk Label gksrk gS] bl Method }kjk Return fd;k tk ldrk gSA ifj.kker% ge bl Method dks Use djds ml Command dk uke izkIr dj ldrs gSa] ftlus ActionEvent Generate fd;k gksrk gSA fdl Modifier (Alt, Ctrl, Shift, Meta) dks Use djrs gq, ActionEvent dks Generate fd;k x;k gS] ml Modifier dh tkudkjh izkIr djus ds fy, ge getModifiers() Method dk iz;ksx dj ldrs gSaA bl Method dk Syntax fuEukuqlkj gksrk gS% int getModifiers()

dksbZ ActionEvent fdl le; ij Generate gqvk gS] bl ckr dh tkudkjh izkIr djus ds fy, ge getWhen() Method dks Use dj ldrs gSaA ;s Method fuEukuqlkj gksrk gS% long getWhen()

ekuyks fd ge ,d Applet Create djrs gSa vkSj ge pkgrs gSa fd tSls gh bl ij fLFkr ,d Command Button dks Click fd;k tk,] Command Button dk Label Change gks tk,A pwafd Command Button dks Click djus ij ActionEvent Generate gksrk gS] blfy, bl Event dks Handle djus ds fy, gesa ActionListener Interface dks Implement djuk gksrk gSA bl Interface dks ge fuEukuqlkj ,d ubZ Class esa Implement dj ldrs gSa% class MyFirstListener implements ActionListener { public void actionPerformed(ActionEvent actnEvnt) { // Executable codes goes here. } } Command Button ls Generate gksus okys ActionEvent dks Handle djus ds fy, ActionListener Interface dks Implement dj ysus ds ckn gesa Command Button dks Listener ls Register djuk gksrk gSA

ge pkgrs gSa fd Applet ij fLFkr Command Button ds Events dks ;s Listener Listen djs] blfy, gesa ,d Applet Create djuk gksxk vkSj ml Applet esa ,d Command Button Create djds mls bl Listener ls Register djuk gksxkA ;s dke ge fuEukuqlkj dj ldrs gSa% class UsingMyFirstListener extends Applet { public void init() 485 Any Question or Suggestion, Just Discuss Here...

Java in Hindi {

Button btnOK = new Button(“OK”);

// Creating Button Object

// Create Listener Object MyFirstListener listenCommandButtonEvent = new MyFirstListener(); // Register Command Button with Listener so that // it can here Command Button’s Events btnOK.addActionListener(listenCommandButtonEvent);

}

}

// Add the Button to the Applet add(btnOK);

bl Applet Coding esa geus Applet ds init() Method dks Override fd;k gSA bl Method esa geus btnOK uke dk ,d u;k Button Object Create fd;k gS] ftl ij Label “OK” Display djus ds fy, Button Class ds Constructor dks Use fd;k gSA pwafd Command Button ls Generate gksus okys Events dks Here djus ds fy, geus MyFirstListener uke dh ,d Class dks Define fd;k gS] ftlesa Command Button ls Generate gksus okys Events dks Listen djus ds fy, ActionListener Interface dks Implement fd;k gSA blfy, gesa bl Listener Class ds ,d Object ls Command Button dks Associate djuk gksrk gSA bl Listener ls Command Button dks Associate djus ds fy, geus listenCommandButtonEvent uke dk MyFirstListener Class dk ,d Object Create fd;k gSA pwafd Command Button ActionEvent Object Generate djrk gS] tks fd Action Event dks Represent djrk gSA blfy, bl Action Event dks listenCommandButtonEvent Listener Object ls Register ;k Associate djus ds fy, addActionListener() Method dks Button Class ds btnOK Button Object ds fy, Invoke djuk gksrk gS vkSj Argument ds :i esa ;s listenCommandButtonEvent Listener Object nsuk gksrk gS] tks Button ls Generate gksus okys Events dks Handle djrk gSA ;kuh pwafd Command Button ls Generate gksus okys Action Events dks MyFirstListener Class dk listenCommandButtonEvent uke dk Listener Object Handle djrk gS] D;ksafd ;s Object ml Listener Class dk Object gS] ftlesa Command Button ls Generate gksus okys Action Event Object dks Handle djus ds fy, ActionListener Interface dks Implement fd;k x;k gS] blfy, btnOK Button ls listenCommandButtonEvent Object dks Register djus ds fy, addActionListener() Method esa Argument ds :i esa listenCommandButtonEvent Listener Object dks Pass djuk gksrk gSA gekjs bl Program esa geus ;s dke fuEu Syntax }kjk fd;k gSA btnOK.addActionListener(listenCommandButtonEvent);

bl iwjh izfØ;k dks gesa fuEu Steps ds vuqlkj Follow djuk gksrk gS%


Java in Hindi 1 pwafd Button Object ActionEvent Generate djrk gS] blfy, bu Actions dks Listen djus ds fy, lcls igys gesa ,d Listener Class cukuh gksrh gS] ftlesa ActionListener Interface dks Implement djuk gksrk gSA 2 Listener Create djus ds ckn gesa Button Object Create djuk gksrk gS vkSj bl Button Object ls Generate gksus okys Events Handle djus ds fy, ftl Listener Class esa ActionListener Interface dks Implement fd;k gksrk gS] ml Class dk ,d Object Create djuk gksrk gSA ;kuh gesa og Source Object Hkh Create djuk gksrk gS] tks Events Generate djrk gS vkSj og Listener Object Hkh Create djuk gksrk gS] tks Source ls Generate gksus okys Events dks Listen djrk gSA 3 Event Generate djus okyk Source Object o Event Listen djus okyk Listener Object nksuksa Object dks Create djus ds ckn gesa Source Object dks Listener Object ls Register djuk gksrk gS] rkfd Source ls Generate gksus okys Events dks Listener Objects Listen dj lds vkSj Event ds Response esa Appropriate dke iwjk dj ldsA blds fy, gesa Component Package ds addTypeListener() Method dks Source ds fy, Invoke djuk gksrk gS vkSj Argument ds :i esa Listener Object nsuk gksrk gSA bl dke dks ge fuEu Syntax vuqlkj Perform djrs gSa% SourceObject.addTypeListener(ListenerObject);

bl iwjs Event Handling Mechanism dk lkjka”k ;s gS fd tc Hkh dksbZ Event Generate gksrk gS] ml Event dks Represent djrk gqvk ,d Appropriate Event Object Create gksrk gSA ml Event dks Listen djus ds fy, ,d Appropriate Listener Interface dks Implement djuk gksrk gS vkSj vUr esa Event Generate djus okys Source o Event dks Listen djus okys Listener nksuksa dk ,d & ,d Object Create djuk gksrk gSA fQj Source ls Listener dks Register djus ds fy, ,d Appropriate Method dks Use djuk gksrk gSA ;kuh gj Event ls lEcaf/kr ,d Interface o ,d Registration Method gksrk gSA fofHkUu izdkj ds Events, muds Listener o Registration Method vkil esa Closely Related gksrs gSa] ftUgsa ge fuEukuqlkj Represent dj ldrs gSa% 1 tc ActionEvent Generate gksrk gS] rc Event dks Listen djus ds fy, gesa ActionListener Interface dks Implement djuk gksrk gS vkSj Source ls Listener dks Associate ;k Register djus ds fy, Source ds lkFk addActionListener() Method dks Use djuk gksrk gSA bl Method dks ge fuEukuqlkj Use djrs gSa% SourceObject.addActionListener(ListenerObject);

2 tc AdjustmentEvent Generate gksrk gS] rc Event dks Listen djus ds fy, gesa AdjustmentListener Interface dks Implement djuk gksrk gS vkSj Source ls Listener dks Associate ;k Register djus ds fy, Source ds lkFk addAdjustmentListener() Method dks Use djuk gksrk gSA bl Method dks ge fuEukuqlkj Use djrs gSa%


Java in Hindi SourceObject.addAdjustmentListener(ListenerObject);

3 tc ComponentEvent Generate gksrk gS] rc Event dks Listen djus ds fy, gesa ComponentListener Interface dks Implement djuk gksrk gS vkSj Source ls Listener dks Associate ;k Register djus ds fy, Source ds lkFk addComponentListener() Method dks Use djuk gksrk gSA bl Method dks ge fuEukuqlkj Use djrs gSa% SourceObject.addComponentListener(ListenerObject);

4 tc ContainerEvent Generate gksrk gS] rc Event dks Listen djus ds fy, gesa ContainerListener Interface dks Implement djuk gksrk gS vkSj Source ls Listener dks Associate ;k Register djus ds fy, Source ds lkFk addContainerListener() Method dks Use djuk gksrk gSA bl Method dks ge fuEukuqlkj Use djrs gSa% SourceObject.addContainerListener(ListenerObject);

5 tc FocusEvent Generate gksrk gS] rc Event dks Listen djus ds fy, gesa FocusListener Interface dks Implement djuk gksrk gS vkSj Source ls Listener dks Associate ;k Register djus ds fy, Source ds lkFk addFocusListener() Method dks Use djuk gksrk gSA bl Method dks ge fuEukuqlkj Use djrs gSa% SourceObject.addFocusListener(ListenerObject);

6 tc ItemEvent Generate gksrk gS] rc Event dks Listen djus ds fy, gesa ItemListener Interface dks Implement djuk gksrk gS vkSj Source ls Listener dks Associate ;k Register djus ds fy, Source ds lkFk addItemListener() Method dks Use djuk gksrk gSA bl Method dks ge fuEukuqlkj Use djrs gSa% SourceObject.addItemListener(ListenerObject);

7 tc KeyEvent Generate gksrk gS] rc Event dks Listen djus ds fy, gesa KeyListener Interface dks Implement djuk gksrk gS vkSj Source ls Listener dks Associate ;k Register djus ds fy, Source ds lkFk addKeyListener() Method dks Use djuk gksrk gSA bl Method dks ge fuEukuqlkj Use djrs gSa% SourceObject.addKeyListener(ListenerObject);

8 tc MouseEvent Generate gksrk gS] rc Event dks Listen djus ds fy, gesa MouseListener Interface dks Implement djuk gksrk gS vkSj Source ls Listener


Java in Hindi dks Associate ;k Register djus ds fy, Source ds lkFk addMouseListener() Method dks Use djuk gksrk gSA bl Method dks ge fuEukuqlkj Use djrs gSa% SourceObject.addMouseListener(ListenerObject);

9 tc MouseWheelEvent Generate gksrk gS] rc Event dks Listen djus ds fy, gesa MouseWheelListener Interface dks Implement djuk gksrk gS vkSj Source ls Listener dks Associate ;k Register djus ds fy, Source ds lkFk addMouseWheelListener() Method dks Use djuk gksrk gSA bl Method dks ge fuEukuqlkj Use djrs gSa% SourceObject.addMouseWheelListener(ListenerObject);

10 tc TextEvent Generate gksrk gS] rc Event dks Listen djus ds fy, gesa TextListener Interface dks Implement djuk gksrk gS vkSj Source ls Listener dks Associate ;k Register djus ds fy, Source ds lkFk addTextListener() Method dks Use djuk gksrk gSA bl Method dks ge fuEukuqlkj Use djrs gSa% SourceObject.addTextListener(ListenerObject);

11 tc WindowEvent Generate gksrk gS] rc Event dks Listen djus ds fy, gesa WindowListener Interface dks Implement djuk gksrk gS vkSj Source ls Listener dks Associate ;k Register djus ds fy, Source ds lkFk addWindowListener() Method dks Use djuk gksrk gSA bl Method dks ge fuEukuqlkj Use djrs gSa% SourceObject.addWindowListener(ListenerObject);

vc ;fn ge iwjk Example Applet Create djsa] rks bl Applet ds Source Code fuEukuqlkj gksaxs% Program // File Name : UsingMyFirstListener.java import java.awt.*; import java.applet.*; import java.awt.event.*; public class UsingMyFirstListener extends Applet { public void init() { Button btnOK = new Button(" OK ");

//Creating Button Object

// Create Listener Object


Java in Hindi MyFirstListener listenCommandButtonEvent = new MyFirstListener(); // Register Command Button with Listener so that // it can here Command Button's Events btnOK.addActionListener(listenCommandButtonEvent);

}

}

// Add the Button to the Applet add(btnOK);

class MyFirstListener implements ActionListener { public void actionPerformed(ActionEvent actnEvnt) { Button source = (Button)actnEvnt.getSource(); source.setLabel("Clicked"); } }

bl Source Code esa ge ns[k ldrs gSa] fd geus MyFirstListener Listener Class esa actionPerformed() Method dks Modify fd;k gSA ActionEvent Class esa getSource() uke dk ,d Method gksrk gSA ;s Method ml Component dk Reference Return djrk gS] ftlus Event Generate fd;k gSA ;kuh Applet Window ij fLFkr Command Button dks Click djus ij tks Click Event Generate gksrk gS] ml Click Event dks Generate djus okys Command Button ds Reference dks getSource() Method }kjk izkIr fd;k tk ldrk gSA pwafd ge Listener esa ftl Object dk Reference izkIr djuk pkgrs gSa] og ,d Command Button gS] blfy, geus MyFirstListener Class esa Button Class dk source uke dk ,d u;k Object Create fd;k gS] rkfd btnOK Button dks bl Class ds actionPerformed() Method esa source uke ds Object }kjk Access dj ldsaA ;s dke geus fuEu Statement }kjk fd;k gS% Button source = (Button)actnEvnt.getSource();

tc Applet Run gksrk gS vkSj ge Applet ij fLFkr btnOK Button ij Click djrs gSa] rks ,d Action Event Generate gksrk gSA bl Action Event dks Listener Listen djrk gS vkSj ftl Object us Event Generate fd;k gS] ml Source Object dks Argument ds :i esa actnEvnt uke ds Object esa izkIr djrk gSA pwafd bl Applet esa btnOK Button gh Action Event Generate dj jgk gS] blfy, actnEvnt uke dk Object btnOK Button dk Reference gh Hold djrk gSA blfy, tc getSource() Method dk iz;ksx djds ml Source Object dk irk yxkuk gksrk gS] ftlus Event Generate fd;k gS] rks btnOK Button dk Reference gh Return gksrk gSA


Java in Hindi pwafd gesa bl Reference dks ,d u, Button izdkj ds Object source esa Store djuk gksrk gS] rkfd Source }kjk btnOK Button dks Refer fd;k tk lds] blfy, Return gksus okys Source Object ds uke dks Button izdkj ds eku esa Convert djus ds fy, (Button) “kCn ls Type Casting fd;k x;k gSA bl rjg ls source uke ds Object esa btnOK Button dk Reference Store gks tkrk gSA ;kuh ;s Object Hkh mlh Memory Location dks Refer djrk gS] tsls btnOK Button Object djrk gSA blfy, ge btnOK Object ds LFkku ij bl source Object dk iz;ksx djds ;fn Button ds Label dks Change djrs gSa] rks btnOK Button dk Label gh Change gksxkA D;ksafd nksuksa gh Objects leku Memory Location dks Refer dj jgs gSaA blfy, btnOK Button dk Label Change djus ds fy, geus fuEu Statement Use fd;k gS% source.setLabel("Clicked");

tc ge btnOK Button ij Click djrs gSa] rc mldk Label “OK” ls Change gksdj “Clicked” gks tkrk gSA bl Program dks fuEukuqlkj Modify djds ge nks Button Objects ls Generate gksus okys Action Events dks vyx&vyx rjhds ls Handle dj ldrs gSaA Program // File Name : UsingMyFirstListener.java import java.awt.*; import java.applet.*; import java.awt.event.*; public class UsingMyFirstListener extends Applet { public void init() { Button btnOK = new Button(" OK "); Button btnCancel = new Button(" Cancel ");

// Creating Button Object

// Create Listener Object MyFirstListener listenCommandButtonEvent = new MyFirstListener(); // Register Command Button with Listener so that // it can here Command Button's Events btnOK.addActionListener(listenCommandButtonEvent); btnCancel.addActionListener(listenCommandButtonEvent);

}

}

// Add the Button to the Applet add(btnOK); add(btnCancel);

class MyFirstListener implements ActionListener { public void actionPerformed(ActionEvent actnEvnt)


Java in Hindi {

}

}

Button source = (Button)actnEvnt.getSource(); if(source.getLabel() == " OK ") source.setLabel("Clicked"); if(source.getLabel() == " Cancel ") source.setLabel("UnClick");

bl Program ds Listener dks ge fuEukuqlkj Modify dj ldrs gSa] tgka getLabel() Method ds LFkku ij getActionCommand() Method dks Use fd;k x;k gSA ;s Method ml Source Command dk Label Return djrk gS] ftlus Action Event dks Generate fd;k gksrk gSA pwafd gekjs Program esa Command Button gh Acton Event Generate dj jgk gS] blfy, bl Method ls Applet ij fLFkr nksuksa Buttons esa ls ml Button dk uke gh Return gksrk gS] ftlus Event Generate fd;k gksrk gSA ;s Modified Listener fuEukuqlkj gS% class MyFirstListener implements ActionListener { public void actionPerformed(ActionEvent actnEvnt) { Button source = (Button)actnEvnt.getSource(); if(source.getActionCommand() == " OK ") source.setLabel("Clicked");

}

}

if(source.getActionCommand() == " Cancel ") source.setLabel("UnClick");

ge fdlh Applet esa ,d nwljs rjhds ls Hkh fofHkUu izdkj ds Events dks Handle dj ldrs gSaA tc ge fdlh Applet esa Delegation Event Model dks Use djuk pkgrs gSa] rc gesa fuEukuqlkj dke djus gksrs gSa% 1 Appropriate Interface dks Applet esa gh Implement djuk gksrk gS] rkfd ;s Interface Desire izdkj ds Event dks Receive dj ldsA 2 ;fn t:jh gks rks Listener dks Event Notification izkIr djus ds fy, ,d Recipient dh rjg Register ;k Un-register djus ds fy, Code Implement djsaA ,d Source Object ,d ls T;knk izdkj ds Event Generate djus esa l{ke gksrk gS vkSj Source }kjk Generate fd, tk ldus okys gj Event dks Handle djus okys fofHkUu Event Handling Methods dks Interface esa vyx ls Define fd;k tkrk gSA blh rjg ls fdlh ,d gh Source Object dks ,d ls vf/kd izdkj ds Events dks Receive djus ds fy, Register fd;k tk ldrk gS] ysfdu tc bl izdkj dh fLFkfr gksrh gS] rc Object }kjk Receive fd, tkus okys fofHkUu izdkj ds Events ftl Interface ls lEcaf/kr gksrs gSa] mu


Java in Hindi lHkh Interfaces dks Implement djuk t:jh gksrk gSA Delegation Event Model fdl izdkj ls dke djrk gS] bls le>us ds fy, ge lcls T;knk Event Generate djus okys Source Keyboard o Mouse dks Handle djuk lh[ksaxsA

Handling Mouse Events Mouse ls lEcaf/kr Events dks Handle djus ds fy, gesa MouseListener o MouseMotionListener Interfaces dks Implement djuk gksrk gSA blds lkFk gh ge MouseWheelListener Method dks Hkh Implement dj ldrs gSaA ysfdu pwafd lHkh yksx Scroll Mouse dk iz;ksx ugha djrs gSa] blfy, ;fn ge bl Interface dks Implement djrs Hkh gSa] rks Hkh Scrolling ls lEcaf/kr Events dsoy Scroll Mouse Use djus okys Computers ij gh Generate o Access gks ikrs gSaA ge vkxs tks Example Applet Develop dj jgs gSa] mlesa Mouse ls lEcaf/kr fofHkUu Events dks Handle fd;k x;k gSA bl Applet Program esa Mouse ds Pointer dh Current Coordinate Position dks Applet ds Status Bar esa Display fd;k x;k gSA bl Applet Example Program esa tc Hkh Mouse ds Button dks Press fd;k tkrk gS] rks Mouse Pointer dh Current Position ij “Down” Word Display gksrk gSA tc Hkh Mouse ds Button dks Release fd;k tkrk gS] rks Mouse Pointer dh Current Position ij “Up” Word Display gksrk gSA blh rjg ls tc Hkh Mouse ds Button dks Click fd;k tkrk gS] rks Applet ds Top-Left Corner ij “Mouse Clicked” Word Display gksrk gSA blh rjg ls tc Mouse dk Pointer Applet Window dh Border ls ckgj tkrk gS ;k Applet Window ds Display Area esa vkrk gS] Applet ij ,d Message Display gksrk gSA tc Program // File Name : MouseListeners.java import java.awt.*; import java.awt.event.*; import java.applet.*; public class MouseListeners extends Applet implements MouseListener, MouseMotionListener { String message = ""; int xPosition = 0, yPosition = 0; //Coordinates of Mouse Pointer public void init() { addMouseListener(this); addMouseMotionListener(this); } // Handle Mouse Click Event public void mouseClicked(MouseEvent mousEvnt) {


Java in Hindi // Save Coordinates xPosition = 0; yPosition = 10; message = "Mouse Clicked"; repaint(); } // Handle Mouse Enter Event in Applet Window Display Area public void mouseEntered(MouseEvent mousEvnt) { // Save Coordinates xPosition = 0; yPosition = 10; message = "Mouse Entered"; repaint(); } // Handle Mouse Exit Event From Applet Window Border public void mouseExited(MouseEvent mousEvnt) { // Save Coordinates xPosition = 0; yPosition = 10; message = "Mouse Exited"; repaint(); } // Handle Mouse Button Press Event in Applet Window public void mousePressed(MouseEvent mousEvnt) { // Save Coordinates xPosition = mousEvnt.getX(); yPosition = mousEvnt.getY(); message = "Down"; repaint(); } // Handle Mouse Button Released Event in Applet Window public void mouseReleased(MouseEvent mousEvnt) { // Save Coordinates xPosition = mousEvnt.getX(); yPosition = mousEvnt.getY(); message = "Up"; repaint(); } // Handle Mouse Drag Event in Applet Window public void mouseDragged(MouseEvent mousEvnt)


Java in Hindi { // Save Coordinates xPosition = mousEvnt.getX(); yPosition = mousEvnt.getY(); message = "*";

}

showStatus("Dragging mouse at "+ xPosition + ", " + yPosition); repaint();

// Handle Mouse Moved Event in Applet Window public void mouseMoved(MouseEvent mousEvnt) { // Show Status showStatus("Dragging mouse at " + mousEvnt.getX() + ", " + mousEvnt.getY()); repaint(); } // Display Message in Applet Window public void paint(Graphics g) { // Show Status g.drawString(message, xPosition, yPosition); } } Output

bl mnkgj.k Applet Program esa geus MouseListener o MouseMotionListener nksuksa Interfaces dks Implement fd;k gSA bu nksuksa Interfaces esa os Methods Include fd, x, gSa] ftUgsa Implement djds ge fofHkUu izdkj ds Mouse Events dks Handle dj ldrs gSaA pwafd ,d Applet esa gh fofHkUu izdkj ds Mouse Events Generate gksrs gSa] blfy, Applet gh fofHkUu izdkj ds Mouse Events dk Source gksrk gS vkSj fofHkUu izdkj ds Mouse Events dks Listen djus okyk Listener Hkh Applet gh gksrk gSA


Java in Hindi bl fLFkfr esa geus Applet ds init() Method dks Override djds Event Generate djus okys Source ;kuh Applet ds lkFk fQj ls blh Applet dks Listener ds :i esa fuEukuqlkj Register fd;k gS% public void init() { addMouseListener(this); addMouseMotionListener(this); }

pwafd ge gekjh Applet Class esa gh Mouse ds gekjk Applet gh Generate gksus okyh fofHkUu Class esa gksrs gSa] mlh Class dks Refer djus blfy, Listener ds Reference ds :i esa geus

Listeners dks Implement dj jgs gSa] blfy, Events dk Listener gksrk gS vkSj ge ftl ds fy, this Object dks Use dj ldrs gSa] this Object dks Use fd;k gSA

blh rjg ls ge ftl Class esa gksrs gSa] ml Class ds Object ds fy, fdlh Hkh Methods dks fcuk Object ds lkFk Dot Operator dk iz;ksx fd, gq,] Directly Use dj ldrs gSaA blhfy, geus addMouseListener() o addMouseMotionListener() nksuksa dks fcuk fdlh Object ds Directly Call fd;k gSA ;fn ge fdlh vU; Class esa blh dke dks djuk pkgrs rks gesa] fuEukuqlkj Syntax dk iz;ksx djuk iMrk% SourceObject.addMouseListener(ListenerObject);

tc bl Applet dks Run djds Mouse ls Events dks Generate djrs gSa] rc fofHkUu Events Generate djus okyk Source Object Applet gh gksrk gS vkSj fofHkUu izdkj ds Events dks Handle djus ds Methods dks blh Applet Class esa Implement fd;k x;k gS] blfy, ;s Applet gh fofHkUu izdkj ds Events dks Listen Hkh djrk gS vkSj gj Event ds Response esa Appropriate Method dks Invoke dj nsrk gSA ftl rjg ls ge fdlh Applet esa mijksDr nks rjhdksa ls Delegation Event Handling dks Perform dj ldrs gSa] mlh rjg ls ge fdlh Application esa Hkh Delegation Event Handling dks Apply dj ldrs gSaA bl izfØ;k dks ge fuEukuqlkj Example }kjk le> ldrs

gSa%

Program // File Name : MyListenrFrame.java import java.awt.*; import java.awt.event.*; public class MyListenerFrame extends Frame { Button btnOK, btnCancel; // The main Method public static void main(String args[]) { MyListenerFrame window = new MyListenerFrame(); }


Java in Hindi // Constructor public MyListenerFrame() { super("My First Event Handled Window"); setLayout(null); // Creating Event Generator Source Button Objects btnOK = new Button("OK"); btnCancel = new Button("Cancel"); btnOK.setBounds(40,45,50,25); btnCancel.setBounds(100,45,50,25); add(btnOK); add(btnCancel); // Creating Listener Object so that it can Listen Button's Events MyFirstListener listenCommandButtonEvent = new MyFirstListener(); // Register Buttons with Listener btnOK.addActionListener(listenCommandButtonEvent); btnCancel.addActionListener(listenCommandButtonEvent);

}

}

// Display the window in a separate size setVisible(true); setSize(200,100);

// The Listener Class class MyFirstListener implements ActionListener { public void actionPerformed(ActionEvent actnEvnt) { Button source = (Button)actnEvnt.getSource(); if(source.getActionCommand() == "OK") source.setLabel("Clicked");

}

}

if(source.getActionCommand() == "Cancel") source.setLabel("UnClick");

Output


Java in Hindi

blh Program dks ge ,d vkSj rjhds ls fuEukuqlkj fy[k ldrs gSa] ftlesa eq[; Class esa gh ActionListener dks Implement dj fy;k x;k gSA ;s Program fuEukuqlkj gS% Program // File Name : MyListenrFrame.java import java.awt.*; import java.awt.event.*; public class MyListenerFrame extends Frame implements ActionListener { Button btnOK, btnCancel; // The main Method public static void main(String args[]) { MyListenerFrame window = new MyListenerFrame(); } // Constructor public MyListenerFrame() { super("My First Event Handled Window"); setLayout(null); // Creating Event Generator Source Button Objects btnOK = new Button("OK"); btnCancel = new Button("Cancel"); btnOK.setBounds(40,45,50,25); btnCancel.setBounds(100,45,50,25); add(btnOK); add(btnCancel); // Register Buttons with Listener btnOK.addActionListener(this); btnCancel.addActionListener(this);

}

// Display the window in a separate size setVisible(true); setSize(200,100);


Java in Hindi public void actionPerformed(ActionEvent actnEvnt) { Button source = (Button)actnEvnt.getSource(); if(source.getActionCommand() == "OK") source.setLabel("Clicked");

}

}

if(source.getActionCommand() == "Cancel") source.setLabel("UnClick");

gekjs MyListenerFrame Class esa gh ActionListener dks tc ge bl rjg ls fdlh Interface dks Implement djrs gSa] rc Event Listener gksrk gS] blfy, ftu Event Generate djus okys gesa Listener ls Register djuk gksrk gS] mu lHkh dks addActionListener() Method }kjk Current Frame ls gh Register fd;k tkrk gS vkSj Current Frame dks Refer djus ds fy, this Object dk iz;ksx fd;k tkrk gSA bl Program esa geus Implement dj fy;k gSA Current Frame gh gekjk Source Objects dks

Handling Keyboard Events Keyboard Events dks Handled djus ds fy, Hkh gesa leku Architecture dks Use djuk gksrk gS] ftls geus Mouse Events dks Handle djus ds fy, Use fd;k gSA vUrj dsoy bruk gS fd tc ge Keyboard ds Events dks Handle djrs gSa] rc gesa KeyListener Interface dks Implement djuk gksrk gSA tSlkfd ge tkurs gSa fd tc Keyboard ls fdlh Key dks Press fd;k tkrk gS] rc KEY_PRESSED Event Generate gksrk gS] ftls Handle djus ds fy, keyPressed() Method Invoke gksrk gSA blh rjg ls tc Keyboard ds fdlh Key dks Press djds Release djrs KEY_RELEASED Event Generate gksrk gS vkSj bl Event dks Handle djus keyReleased() Method Invoke gksrk gSA tc Keyboard ls KEY_TYPED Generate gksrk gS] rc bl Event dks Handle djus ds fy, keyTyped() Method gksrk gSA

gSa] rc ds fy,

Event Invoke

User tc Hkh Keyboard ij fdlh Key dks Press djrk gS] rc de ls de nks Events KEY_PRESSED o KEY_RELEASED rks Generate gksrs gh gSa] fQj Hkh vDlj rhuksa Events Generate gks tkrs gSaA

tc gesa dsoy Key ds Character dks gh Process djuk gksrk gS] rc gesa KEY_PRESSED o KEY_RELEASED bu nksuksa Events dks Handled djus dh t:jr ugha gksrh gSA ysfdu tc gesa Special Keys ds lkFk Processing djuh gksrh gS] rc gesa KEY_PRESSED Event dks gh Handle djuk gksrk gSA dksbZ Key Process djus ls igys gesa ,d dke vkSj djuk iMrk gSA gesa ftl Object ds fy, Key dks Press djuk gksrk gS] ml Object ds fy, Input Focus dks izkIr djuk gksrk gS] rkfd Input gksus okyh Key ml Object ij gh tk,A Input Focus dks izkIr djus ds fy, gesa 499 Any Question or Suggestion, Just Discuss Here...

Java in Hindi requestFocus() Method dks Use djuk gksrk gS] ftls Component Package esa Define

fd;k x;k gSA

;fn ge bl Method }kjk vius Application ds fy, Focus izkIr ugha djsaxs] rks gekjk Program Press fd, x, Key dks Receive ugha djsxkA vxys Program esa geus Keyboard Input dks vius Applet esa izkIr fd;k gS vkSj Keyboard ls vkus okyh Key dks Applet ij Display fd;k gS] lkFk gh Generate gksus okys Event dks Hkh Applet ij n”kkZ;k gSA Program // File Name : KeyStrockDemonstracton.java import java.awt.*; import java.awt.event.*; import java.applet.*; public class KeyStrockDemonstracton extends Applet implements KeyListener { String message = ""; int xPosition = 10, yPosition = 20; // Output Coordinates public void init() { addKeyListener(this); requestFocus(); }

// Register Listener with Applet // Request Input Focus for current program

public void keyPressed(KeyEvent keyEvnt) { showStatus("Key Pressed"); } public void keyReleased(KeyEvent keyEvnt) { showStatus("Key Released"); } public void keyTyped(KeyEvent keyEvnt) { message = message + keyEvnt.getKeyChar(); repaint(); }

}

public void paint(Graphics g) { g.drawString(message, xPosition, yPosition); }

Output


Java in Hindi

bl Program esa geus Applet esa Keyboard ds rhuksa Events dks Handle fd;k gSA pwafd ;s Applet Event Generate djus okyk Source Hkh gS vkSj Event Listen djus okyk Listener Interface Hkh blh Applet Class esa Implement fd;k x;k gS] blfy, Source Applet Class dks mlh Listener Applet Class ls Register djus ds fy, geus Applet ds init() Method dks Override djds fuEukuqlkj Define fd;k gS% public void init() { addKeyListener(this); requestFocus(); }


Applet fofHkUu Keystroke Events dks izkIr dj lds] blds fy, geus requestFocus() Method dks Hkh blh Method esa Call fd;k gSA showStatus() Method Applet ds Status Bar dks Represent djrk gS] blfy, fofHkUu izdkj ds Messages dks Display djus ds fy, geus bl Method dks Use fd;k gSA getKeyChar() Method Keyboard ls Press fd, x, Key ds Character dks Return djrk gS] blfy, bl Method }kjk geus Keyboard ls vkus okys Characters dks Message uke ds String Object esa izkIr fd;k gSA fQj paint() Method esa bl Message esa Stored Message dks Applet ij Draw fd;k gSA

tc ge Keyboard ls fdlh Key dks Type djrs gSa] rc ,d KeyEvent Object Generate gksrk gS vkSj KeyTyped() Method Invoke gksrk gSA bl KeyEvent Object esa Type fd, x, Key dk Character gksrk gSA bl Character dks izkIr djus ds fy, keyEvnt Object ls getKeyChar() Method dks fuEukuqlkj Use djds message uke ds String Object esa izkIr fd;k x;k gSA public void keyTyped(KeyEvent keyEvnt) { message = message + keyEvnt.getKeyChar(); repaint(); }

pwafd tc repaint() Method paint() Method dks Execute djds Applet dh Screen dks Repaint djrk gS] rc message uke ds Object esa tks Hkh String gksrh gS] og Screen ij Draw gks tkrh gSA blfy, fiNyk Message Delete gks tkrk gS vkSj u;k Message Paint gks tkrk gS] tks fd message uke ds Object esa gksrk gSA bl Method esa geus message Object dks ftl rjg ls gj KEY_TYPE Event ij Update fd;k gSA


Java in Hindi ,slk blfy, fd;k x;k gS] rkfd message dk iqjkuk Character Hkh Applet ij Draw gks tk,A ;fn ge bl message Object dks bl izdkj ls Update uk djsa] rks gj ckj message esa Currently Press fd;k x;k] Character gh gksxk vkSj dsoy ,d gh Character Screen ij Display gksxkA bl Applet dks Run djrs le; ;fn ge fdlh Special Key tSls fd Shift, Ctrl, Alt ;k fdlh Function Key dks Press djrs gSa] rks gekjh Screen ij dqN Hkh Display ugha gksrk gSA bu Keys dks Respond djus ds fy, gesa keyPressed() Handler dks Use djuk gksrk gSA bu Keys dks keyTyped() Method }kjk Manage ugha fd;k tk ldrk gSA bl Keys dks Identify djus ds fy, gesa buds Virtual Codes dks Use djuk gksrk gSA bl izfØ;k dks ge vxys Program }kjk le> ldrs gSaA Program // File Name : SpecialKeyStrockDemonstracton.java import java.awt.*; import java.awt.event.*; import java.applet.*; public class SpecialKeyStrockDemonstracton extends Applet implements KeyListener { String message = ""; int xPosition = 10, yPosition = 20; // Output Coordinates public void init(){ addKeyListener(this); requestFocus(); }


public void keyPressed(KeyEvent keyEvnt){ showStatus("Key Pressed"); int key = keyEvnt.getKeyCode(); switch(key) { case KeyEvent.VK_F1: message += ""; break; case KeyEvent.VK_F2: message += ""; break; case KeyEvent.VK_F3: message += ""; break; case KeyEvent.VK_PAGE_DOWN:


Java in Hindi message += ""; break; case KeyEvent.VK_PAGE_UP: message += ""; break; case KeyEvent.VK_LEFT: message += ""; break; case KeyEvent.VK_UP: message += ""; break;

}

} repaint();

public void keyReleased(KeyEvent keyEvnt) { showStatus("Key Released"); } public void keyTyped(KeyEvent keyEvnt) { message = message + keyEvnt.getKeyChar(); repaint(); }

}

public void paint(Graphics g) { g.drawString(message, xPosition, yPosition); }

Output

Adapters tc ge Listeners Create djus ds fy, Interfaces dk iz;ksx djrs gSa] rc Listener Class dks mu lHkh Methods dks Override djuk gksrk gS] ftUgsa Interface esa Declare fd;k x;k gSA 503 Any Question or Suggestion, Just Discuss Here...

Java in Hindi dbZ Interfaces esa dsoy ,d Method gksrk gS] tcfd dbZ Interfaces esa dbZ Methods gksrs gSaA gkykafd ge dsoy ,d gh Event dks Handle djuk pkgrs gSa] ysfdu fQj Hkh gesa Interface ds lHkh Methods dks Override djuk iMrk gSA bl leL;k ls cpus ds fy, Event Package gesa lkr Adapter Classes Provide djrk gSA Adapter Classes gesa fdlh Event Listener Interface ds lHkh Methods dh Empty Implementation Provide djrk gSA ;kuh fdlh Event Listener Interface ds lHkh Methods dks Adapter Classes esa igys ls gh Implement fd;k tk pqdk gksrk gS] ftudh Body Empty jgrh gSA pwafd Interface ds lHkh Methods dh Body Empty jgrh gS] blfy, dksbZ Hkh Method dksbZ dke ugha djrk gSA

tc gesa fdlh Interface ds fdlh Method dks Implement djuk gksrk gS] rc ge mldh Adapter Class dks Inherit djds dsoy ml Interface dks Implement dj ysrs gSa] ftldh gesa t:jr gksrh gSA bl izdkj ls ge fdlh Event Listener Interface ds lHkh Methods dks Implement djus dh t:jr ugha gksrh gS] cfYd dsoy mu Methods dks Implement djuk gksrk gS] ftudh gekjs Program esa t:jr gksrh gSA mnkgj.k ds fy, ekuyks fd gesa gekjs fdlh Program esa Mouse ds MouseMotionListener Interface dks Implement djuk gSA vc ;fn ge bl Interface dks Use djuk pkgrs gSa] rks gesa gekjs Program esa blds nksuksa Methods mouseDragged() o mouseMoved() dks Implement djuk t:jh gksrk gSA fQj pkgs gesa gekjs Program esa dsoy mouseDragged() Method dh gh t:jr D;ksa uk gksA bl fLFkfr ls cpus ds fy, ge MouseMotionAdapter Class dk iz;ksx dj ldrs gSa] D;ksafd bl Adapter Class esa bu nksuksa Methods dks igys ls gh Implement fd;k tk pqdk gS] ftudh Body Empty gSA gesa bl Class ds ,d ubZ Class esa Inherit djuk gSA ,slk djus ij Mouse ds nksuksa Empty Implemented Methods gekjh ubZ Class esa Inherit gks tkrs gSaA vc bl ubZ Class esa ge Mouse ds nksuksa Methods esa ls ftl Method dks Implement djuk pkgrs gSa] mls Override djds Implement dj ysrs gSa vkSj MouseMotionListener Interface ds nksuksa Methods dks Implement djus ls cp tkrs gSaA bl rjhds esa ge ftl Method dks Implement ugha djrs gSa] mls Adapter Class esa Define fd;k x;k Empty Body okyk Method Handle djrk gSA java.awt.event Package esa fuEukuqlkj lkr Adapter Classes dks Define fd;k x;k gS] tks Generally Use gksrs gSaA lkFk gh ;s Hkh crk;k x;k gS fd os fdl Listener Interface dks Implement dj jgs gSaA


Java in Hindi

Event Listener Interface Classes o Event Listener Adapter Classes nksuksa gh izdkj dh Classes Applet dk ,d Reference Save djrh gSaA ;s Information ,d Argument ds :i esa muds Constructor dks Pass fd;k tk ldrk gS vkSj budk iz;ksx ckn esa showStatus() Method dks Invoke djus ds fy, fd;k tk ldrk gSA

pfy,] Adapter Classes dk iz;ksx djrs gq, Events dks ,d Example Program }kjk Handle djuk lh[krs gSaA vHkh rd geus ftrus Hkh Application Create fd, gSa] mu lHkh ds Window ds Close Button ij Click djus ij Hkh os Window Close ugha gksrs gSaA ;s Window rc Close gksrs gSa] tc ge Command Window dks Close djrs gSaA Display gksus okyk Frame Window mlds Close Button dks Click djus ij Close gks lds] blds fy, gesa Frame Window ds Closing Event dks Handle djuk t:jh gksrk gSA fuEu Program esa geus ;gh fd;k gSA Program // File Name : AdapterClassesDemonstracton.java import java.awt.*; import java.awt.event.*; public class AdapterDemonstrationApp extends Frame { public static void main(String args[]) { AdapterDemonstrationApp window = new AdapterDemonstrationApp();


Java in Hindi }

window.setBounds(10,10,150,100);

// Constructor public AdapterDemonstrationApp() { // Register the listener for the window super("The window adapter");

}

}

WindowListener listenWindowEvent = new WindowListener(); addWindowListener(listenWindowEvent); setVisible(true);

class WindowListener extends WindowAdapter { // Event handler for the window closing event

}

public void windowClosing(WindowEvent wndEvnt) { AdapterDemonstrationApp source; source = (AdapterDemonstrationApp)wndEvnt.getSource(); source.dispose(); System.exit(0); }

bl Program esa Main Class ds main() Method esa geus ,d Frame Window Create fd;k gSA bl Frame Window ds Constructor esa gh geus ,d Listener Object Create fd;k gS vkSj Current Class dks ml Listener Object ls Register fd;k gSA pwafd Current Class ,d Window Create djrk gS] blfy, Current Class esa Current Window ls lEcaf/kr tks Hkh Event Generate gksxk] mls og Listener Object Listen djsxkA Listener Object Current Window ds Closing Events dks Listen dj lds] blds fy, geus Window Adapter Class dks Extend fd;k gS vkSj bl Class esa windowClosing() Method dks Implement fd;k gSA ;s Method rc Invoke gksrk gS] tc Frame Window dks Close fd;k tkrk gSA

tc Frame Window dks Close fd;k tkrk gS] rc Window dks Close djus dk Event Generate gksrk gSA bl Event dks listenWindowEvent Object Listen djrk gS vkSj bl Event ds Response esa Extended dh xbZ WindowListener Listener Class dk windowClosing() Method Execute gksrk gSA tks Event Generate gksrk gS] ml Event dks ;s Listener wndEvnt Object esa izkIr djrk gSA pwafd tks Event Generate gksrk gS] og Event AdapterDemonstrationApp Class ds Object esa Generate gksrk gS] blfy, bl Event dks Listener Class esa Refer djus ds fy, gesa Listener Class esa fQj ls blh Class dk source uke dk ,d Object Create djuk


Java in Hindi gksrk gSA tc ge leku Class dk nwljk Object Create djds mlesa wndEvnt Object ls mlds Generator Object dks getSource() Method }kjk Return djokrs gSa] rc og Object Refer gksrk gS] ftlus Event Generate fd;k gksrk gSA pwafd og Object AdapterDemonstrationApp Class dk Object gS] blfy, blh Class dk source uke dk Object mls Refer dj ldrk gS vkSj ge source Object ds Reference esa tks Method Call djrs gSa] og Method Event Generate djus okys Object ds Reference esa gh Call gksrk gS vkSj Window Close gks tkrk gSA WindowListener Class ftls geus Adapter Class ls Extend fd;k gS] bl Class esa ge ns[k ldrs gSa fd geus dsoy windowClosing() Method dks gh Implement fd;k gS] tcfd Window ls lEcaf/kr lkr Methods gksrs gSaA

,slk blhfy, lEHko gS] D;ksafd ckdh ds Methods dks Empty Body ds lkFk WindowAdapter Class esa igys ls gh Implement fd;k tk pqdk gSA blfy, tc Window Closing ds vykok Window ls lEcaf/kr dksbZ vU; Events Generate gksrs gSa] rc mUgsa Adapter ds Empty Body okys Methods Handle dj ysrs gSaA ge Applet esa Hkh Event Handling djus ds fy, Adapter Classes dks Use dj ldrs gSaA bl izfØ;k dks ge fuEu Applet }kjk le> ldrs gSa% Program // File Name : AdapterApplet.java import java.awt.*; import java.awt.event.*; import java.applet.*; public class AdapterApplet extends Applet { public void init() { addMouseListener(new MyMouseListener(this)); } } class MyMouseListener extends MouseAdapter { AdapterApplet adapterApplet; public MyMouseListener(AdapterApplet adapterApplet) { this.adapterApplet = adapterApplet; }

}

public void mousePressed(MouseEvent mousEvnt) { adapterApplet.showStatus("Mouse Pressed"); }


Java in Hindi bl Program esa MouseAdapter Class dks Extend djds MyMouseListener Class Create fd;k x;k gSA bl Class dk Object Applet esa Generate gksus okyh Mouse Events dks Listen djrk gSA MouseListener esa dqy ikap Methods gksrs gSa] ftUgsa Implement djuk gksrk gSA pwafd ge MouseAdapter Class dks Extend dj jgs gSa] blfy, gesa bl Class esa ;s lqfo/kk feyrh gS fd gesa Mouse ds ftl Method dks Use djuk gksrk gS] ge dsoy mlh Method dks Implement dj ldrs gSa vkSj gesa “ks’k Methods dks Implement djus dh t:jr ugha gksrh gSA pwafd gekjk ;s Listener ftl Applet ds Events dks Listen djus okyk gS] ml Applet Class ds ,d Reference Object dh t:jr bl Listener dks gksrh gS] rkfd ;s Listener ml Applet ds fy, fofHkUu Methods dks Invoke dj ldsA blfy, MyMouseListener Class esa geus AdapterApplet Class dk ,d Object adapterApplet Create fd;k gSA AdapterApplet og Applet Class gS] ftlds fy, MyMouseListener Class dks Extend fd;k x;k gSA tc ge mousePressed() Method esa bl adapterApplet Object ds fy, showStatus() Method dks Invoke djrs gSa] rks ;s Method Display gksus okys Actual Applet ds Status Bar dks Refer djrk gS vkSj tks Message Display gksuk gksrk gS] og Display gksus okys Applet ds Status Bar ij fn[kkbZ nsrk gSA

tc ;s Program Run djrs gSa] rc lcls igys Applet Initialize gksrk gSA Applet Initialize djus ds fy, Applet dk fuEu init() Method Execute gksrk gS% public void init() { addMouseListener(new MyMouseListener(this)); }

;fn ge pkgsa rks bl Method dks fuEukuqlkj Hkh Define dj ldrs gSa% public void init() { MyMouseListener listenAppletEvent = new MyMouseListener(this); addMouseListener(listenAppletEvent); } Applet Initialize gksrs gh nks dke gksrs gSaA lcls igys MyMouseListener Class dk ,d Object listenAppletEvent Create gksrk gSA tc ;s Object Crete gksrk gS] rc bl Object ds Constructor esa AdapterApplet Class dk ,d Object Argument ds :i esa Pass fd;k tkrk gSA ,slk blfy, fd;k tkrk gS] rkfd Listener dks ;s irk py tk, fd mls fdl Class ls Generate gksus okys Events dks Listen djuk gSA

pwafd ;s Object Current Applet ls Generate gksus okys Events dks Handle djus ds fy, Create fd;k x;k gS] blfy, bl Constructor esa this Object Pass fd;k x;k gS] tks Current Applet dks Represent djrk gSA Listener Class dk Object Create djus ds fy, tkok MyMouseListener Class dk 1-Argument Constructor Execute djrk gS] tks fd fuEukuqlkj gS%


Java in Hindi public MyMouseListener(AdapterApplet adapterApplet) { this.adapterApplet = adapterApplet; }

tc MyMouseListener Class dk Object Create djus ds fy, tc ;s Constructor Execute gksrk gS] rc Argument ds :i esa ml Class dk Reference ysdj vkrk gS] ftlds Events dks bls Listen djuk gSA pwafd Applet Class esa bl Constructor ds fy, this Object ;kuh AdapterApplet Class dk Reference Pass fd;k x;k gSA ,slk blfy, fd;k tkrk gS] rkfd MyMouseListener Class esa Create fd, x, adapterApplet Object dks this Object esa vkus okys Reference dks Store fd;k tk ldsA tc ge Listener Class esa Create fd, x, AdapterApplet Class ds Object esa Applet Class dk Reference Pass djrs gSa] rc ml Actual Applet dks Listener esa Create fd;k x;k ;s Object Hkh Refer djus yxrk gSA blfy, vc ;fn ge bl Listener Class esa adapterApplet Object ds lkFk fdlh Method dks Invoke djsa] rks og Method okLro esa Actual Applet Object ds fy, Call gksrk gSA Applet ls Generate gksus okys Events dks Listener Object ls Register djus ds fy, Applet ds init() Method esa addMouseListener() Method dks Call fd;k gSA ;s Method Applet dks mlds Listener ls Connect ;k Register dj nsrk gSA bl rjg ls ge ,d Applet esa Hkh Adapter Classes dks Use dj ldrs gSaA

Inner Classes and Anonymouse Inner Classes for Simplifying Adapter Classes Inner Class ,d ,slh Class gksrh gS] ftls fdlh Class ds vUnj Define fd;k tkrk gSA bUgsa Nested Class Hkh dgrs gSaA budk iz;ksx djds ge Program dh Coding esa Additional Clarity izkIr dj ldrs gSaA ,d Inner Class dsoy mlh Class ds fy, Available gksrh gS] ftlesa Inner Class dks Define fd;k x;k gksrk gSA Inner Class dk Object Outer Class ds Members dks Access djus esa l{ke gksrk gSA ;kuh ge Inner Class ds Object ls Outer Class ds Data Members o Member Methods dks Directly Access dj ldrs gSaA tcfd Outer Class ;fn Inner Class ds Members dks Access djuk pkgs] rks og ;s dke Inner Class dk ,d Object Create djds ml Object ds lkFk Inner Class ds Members dk iz;ksx djds dj ldrk gSA vc ge ;s tkusaxs fd ge fdl izdkj ls ,d Inner Class dks Event Handling ds fy, Use djds ge Event Adapter Classes dks Use djrs le; fdl rjg ls viuh Coding dks Simple cuk, j[k ldrs gSaA fiNys Program }kjk bl Technique dks le>us dh dksf”k”k djrs gSa] ftlesa Listener Class dks Applet Class ls ckgj Define fd;k x;k gSA bl Applet Class dk eq[; Purpose ;s gS fd tc Applet ij Mouse ds fdlh Key dks Press fd;k tk,] rc Applet ds Status Bar esa “Mouse Pressed” String Display gksuh pkfg,A


Java in Hindi bl Program esa nks Top Level Classes Define dh xbZ gSaA ,d Event Source Class dks Applet Class ls Extend fd;k x;k gS tcfd Event Listener Class dks MouseAdapter Class ls Extend fd;k x;k gSA bl Program esa ge ns[k ldrs gSa fd Applet dk Reference Argument ds :i esa MyMouseListener Constructor dks fn;k x;k gSA bl Reference dks ckn esa mousePressed() Method esa Use djus ds fy, ,d adapterApplet Object esa Store djds j[kk x;k gSA tc Mouse dk dksbZ Button Press fd;k tkrk gS] rc mousePressed() Method ml Applet ds showStatus() Method dks Invoke djrk gS] ftlds Reference dks adapterApplet uke ds AdapterApplet Class ds Object esa Store djds j[kk x;k gSA nwljs “kCnksa esa dgsa rks showStatus() Method dks Actual Applet ds Reference Object adapterApplet ds Reference }kjk Call fd;k x;k gSA blh dke dks ge ,d Inner Class dk iz;ksx djds Hkh dj ldrs gSa] ftls vxys Program esa Explain fd;k x;k gSA Program // File Name : InnerAdapterApplet.java import java.awt.*; import java.awt.event.*; import java.applet.*; public class InnerAdapterApplet extends Applet{ public void init(){ addMouseListener(new MyMouseListener()); }

}

class MyMouseListener extends MouseAdapter{ public void mousePressed(MouseEvent mousEvnt){ showStatus("Mouse Pressed"); } }

;s Program Hkh ogh dke djrk gS] tks fiNyk Program djrk gSA bl Program ds Applet ij Hkh tc ge Click djrs gSa] rc Applet ds Status Bar esa “Mouse Pressed” String Display gksrk gSA ysfdu ge ns[k ldrs gSa] fd bl Program esa gesa fdrus de dke djus iMrs gSaA ftl rjg ls ge fdlh Applet esa Inner Adapter Classes Define djds Applet ds Events Handle dj ldrs gSa] mlh rjg ls ge fdlh Application esa Hkh dj ldrs gSaA bl izfØ;k dks ge fuEu Program }kjk le> ldrs gSa] ftlesa ,d Frame Window dks Close djus ds fy, Window ds windowClosing() Method dks Implement fd;k tk jgk gSA Program // File Name : InnerAdapterApp.java import java.awt.*; import java.awt.event.*; public class InnerAdapterApp extends Frame


Java in Hindi {

// main() Method public static void main(String args[]) { InnerAdapterApp window = new InnerAdapterApp(); } // Constructor of the InnerAdapterApp Class public InnerAdapterApp() { // Register the Frame Window with the Listener MyWindowListener listenWindowEvent = new MyWindowListener(); addWindowListener(listenWindowEvent);

}

}

setVisible(true); setSize(150,100);

// Inner Class Definition class MyWindowListener extends WindowAdapter { // Window Closing Event Handler public void windowClosing(WindowEvent wndEvnt) { InnerAdapterApp source = (InnerAdapterApp)wndEvnt.getSource(); source.dispose(); System.exit(0); } }

bl Program dks Execute djus ij lcls igys main() Method Execute gksrk gSA bl Method esa InnerAdapterApp Class dk ,d Object Create fd;k x;k gSA tc bl Class dk Object Create fd;k tkrk gS] rc bl Class dk Constructor Execute gksrk gSA ;s Frame Window Event Generate djus okys Source dh rjg dke djrk gSA Window ls Generate gksus okys Window Events dks Listen djus ds fy, blh Class esa ,d Inner Class Define dh xbZ gS vkSj bl Inner Class dks WindowAdapter Class ls Derive fd;k x;k gSA Current InnerAdapterApp Class ls Generate gksus okys Events dks Listener ij Hkstus ds fy, addWindowListener() Method dk iz;ksx fd;k x;k gS vkSj Argument ds :i esa bl Method esa MyWindowListener Class ds listenWindowEvent Object dks Pass fd;k x;k gSA

pwafd Current Class dks gh Event Generator ds :i esa Use fd;k tk jgk gS] blfy, blds Object ds lkFk bl Registration Method dks Call djus dh t:jr ugha gSA ge Directly addWindowListener() Method dks Call dj ldrs gSaA


Java in Hindi tc Window dks Close djus ds fy, Window ds Close Button ij Click djrs gSa] rc ,d WindowEvent Generate gksrk gSA ;s Window Event Listener Object Listen djrk gS vkSj Event ds Response esa Listener Class dk windowClosing() Method Execute gksrk gSA bl Method ds Execute gksrs gh blesa Frame Window Class dk source uke dk ,d Object Create fd;k tkrk gSA pwafd wndEvnt Window Event Object esa ml Window dks Reference gksrk gS] ftlus Event Generate fd;k gksrk gSA blfy, getSource() Method dk iz;ksx djds ml Window dk Reference izkIr dj fy;k tkrk gS] ftlus Event Generate fd;k gksrk gSA vc Event Generate djus okys Window dks ge source Object }kjk Refer dj ldrs gSaA blfy, tc ge source Object ds fy, dispose() Method dks Call djrs gSa] rks og Actual Frame Window ds fy, Call gksrk gS vkSj Frame Window dks Close dj nsrk gSA bl rjg ls ge fdlh Application esa Hkh Inner Class ds :i esa Adapter Class dks Extend djds Event Handling dj ldrs gSaA bl mnkgj.k esa geus ns[kk fd Events dks Handle djus ds fy, ge ,d Separate Inner Class Define dj ldrs gSa] tks fd Outer Class ls Generate gksus okys Events dks Listen djus ds fy, Required Listener Interfaces dks Implement djrk gSA fiNys Program esa geus Outer Class ds Constructor esa Inner Class dk ,d Object Create fd;k gSA pwafd eq[; Class esa geus Listener Class dks Inner Class dh rjg Define fd;k gS vkSj ge le> ldrs gSa fd nksuksa gh Classes ,d nwljs ls Unrelated gSa] tcfd nksuksa Classes vkil esa feydj Event Handling dk dke djrh gSaA ;kuh eq[; InnerAdapterApp Frame Class Event Generate djus okyh Source Class gS] tcfd Inner Class Outer Class ls Generate gksus okyh Events dks Listen djus okyh Listener Class gSA nks Unrelated Classes dks vkil esa Related djus ds fy, gesa eq[; Class esa nwljh Class dk ,d Object Create djuk iMrk gS] fQj pkgs og nwljh Class dksbZ Inner Class gks ;k dksbZ vU; Class gksA ;kuh gesa Composition Concept dks Use djuk gksrk gSA tc ge fdlh Class esa fdlh nwljh Unrelated Class dk Object Create djds nksuksa Classes ds chp fdlh izdkj dk Relation cukrs gSa] rkfd nksuksa Classes vkil esa feydj fdlh dke dks iwjk dj ldsa] rks bl izfØ;k dks nwljh Class dk igyh Class esa Compose gksuk dgrs gSaA gekjs Program dh eq[; Class ;k Outer Class ds Constructor esa geus Inner Class dk Object Create djds mls eq[; Class esa Compose fd;k gSA ,slk djus ij nks Unrelated Classes vkil esa Relate gks tkrh gSaA Inner Class dk ,d Object Outer Class esa ,d Data Member dh rjg Create djus ds fy, geus new Operator dks Use fd;k gSA ;fn ge pkgsa rks nks Unrelated Classes dks vkil esa fuEukuqlkj Coding }kjk Hkh Relate dj ldrs gSa% OuterClass out = new OuterClass(“Title”); out.InnerUnrelatedClass inUnrelated = new OuterClass().InnerUnrelatedClass();

ge fdlh Method dh Body esa Hkh fdlh Class dks Define dj ldrs gSaA bl fLFkfr esa Inner Class ml Method dh Body esa Define fd, x, Variables dks Hkh Access djus esa l{ke


Java in Hindi gks tkrh gS] ftlesa Inner Class dks Define fd;k x;k gSA tc ge bl izfØ;k dks Use djuk pkgrs gSa] rc gesa Inner Class dks gesa”kk Method ds Variables dks Declare djus ds ckn Define djuk pkfg,] rkfd Inner Class Method ds mu Variables dks Access dj ldsA lkekU;r;k ge ftu Class dks Inner Classes ds :i esa Define djrs gSa] os Classes Current Outer Class ds vykok fdlh Hkh vU; Outer Class ds fy, Accessible ugha gksrh gSaA blfy, ge ,slh Classes dks fcuk mudk uke Specify fd, gq, Hkh Define dj ldrs gSaA ;kuh ge Inner Classes Create djrs le; Classes dks Nameless Classes ds :i esa Define dj ldrs gSaA ,d ,slh Inner Class ftldk dksbZ uke ugha gksrk gS] Anonymous Class dgykrh gSA Event Handling ds fy, ge ftu Inner Classes dks Define djrs gSa] mu Classes dks Anonymous Class ds :i esa Hkh ifjHkkf’kr fd;k tk ldrk gSA fuEu Program esa geus Status bar esa “Mouse Pressed” String Display djus okys Program dks gh ,d Anonymous Class dk Use djrs gq, Modify fd;k gSA Program fuEukuqlkj gS% Program // File Name : AnonymousInnerApplet.java import java.awt.*; import java.awt.event.*; import java.applet.*; public class AnonymousInnerApplet extends Applet { public void init() { addMouseListener(new MouseAdapter() { public void mousePressed(MouseEvent mousEvnt) { showStatus("Mouse Pressed"); } }); } }

bl Program esa AnonymousInnerApplet uke dh ,d gh Top-Level Class gSA bl Program esa Applet ds init() Method esa addMouseListener() Method dks Call fd;k x;k gSA ;s Method Event Generate djus okys Source Class ;kuh AnonymousInnerApplet Applet Class dks Event Listener djus okyh Listener Class ;kuh AnonymousInnerApplet Applet Class ls Register djrk gSA bl Method esa Argument ds :i esa geus ,d Inner Class dks Define fd;k gS] tks fd ,d Anonymous Class gS] ftldk dksbZ uke ugha gSA pfy,] addMouseListener() Method ds bl Argument dks le>us dh dksf”k”k djrs gSaA new MouseAdapter() {. . . } Statement Compiler dks ;s Instruction nsrk gS fd Braces ds chp Define fd, x, Syntaxes ,d Anonymous Inner Class ds Statements gSaA


Java in Hindi blfy, ;s Inner Class MouseAdapter Class dks Extend djrk gSA bl ubZ Class dk dksbZ uke ugha gksrk gS] ysfdu tSls gh ;s Expression Execute gksrk gS] MouseAdapter Class Inherit gks tkrk gSA pwafd bl Inner Class dks AnonymousInnerApplet Class ds Scope esa Define fd;k x;k gS] blfy, ;s Inner Class AnonymousInnerApplet Class ds fdlh Hkh Data Member o Method dks Access djus esa l{ke gSA blhfy, ;s Class AnonymousInnerApplet Class showStatus() Method dks Directly Call dj ldrk gSA ;fn ge ljy “kCnksa esa dgsa rks addMouseListener() Method Event Generate djus okyh Source AnonymousInnerApplet Class dks MouseAdapter Listener Class ls Directly Register dj nsrk gS] D;ksafd bl Method esa Argument ds :i esa gesa”kk Listener Class ds ,d Object dk Reference Argument ds :i esa fn;k tkrk gS] tcfd bl Program esa geus Directly MouseAdapter Class dk ,d Nameless Object “new MouseAdapter()” Statement }kjk Pass dj fn;k gSA blfy, Create gksus okys Nameless Listener Object ls Current Applet Class Register gks tkrk gS vkSj bl Applet esa ftrus Hkh Events Generate gksrs gSa] mUgsa og Nameless Listener Listen djrk gSA

Window Fundamentals of JAVA

Event Handling Mechanism ds rhu rjhdksa ds ckjs esa tkuus ds ckn vc ge igys tkok ds Window Basics dks le>saxsA tkok ds AWT esa fofHkUu izdkj ds Window Create djus ls lEcaf/kr Classes Define dh xbZ gSaA ge fdlh GUI Application esa ftrus Hkh GUI Components ns[krs gSa] mu lHkh Components dks ge Window dg ldrs gSaA Panel Class ls nks lcls T;knk Use fd, tkus okys Window ftls ge Applet o Frame dgrs gSa] Use fd;k tkrk gSA ;s nksuksa Classes Standard Window Create djus ds fy, Use dh tkrh gSaA bu nksuksa Classes ls gesa ftruh Functionalities gksrh gSa] muesa ls T;knkrj Functionalities budh Super Classes ls Derived gksrh gSaA

Container Class ;s Class Component Class dh Sub Class gS] ftlesa dqN Additional Methods gksrs gSa] tks vU; Component Objects dks Container esa Nest djus dh lqfo/kk iznku djrs gSaA D;ksafd fofHkUu izdkj ds GUI Components dh Base Class Container Class gksrh gS] blfy, ge fofHkUu izdkj ds GUI Components dks Container Object esa Store dj ldrs gSaA ,d Container Object esa fLFkr fofHkUu izdkj ds GUI Objects ds Layout dks Set djus dh lkjh ftEesnkjh Container dh gksrh gSA fofHkUu izdkj ds GUI Components dks Container esa Layout ;k Position djus ds fy, ,d Container Object fofHkUu izdkj ds Layout Objects dk iz;ksx djrk gSA


Java in Hindi Panel Class

Panel Class Container Class dh ,d Sub Class gSA ;s ,d ,slk Component gksrk gS] tks Lo;a ,d Visual Component ugha gksrk gS vkSj blesa dksbZ u;k Method ugha gksrk gS] cfYd ;s dsoy Container Class dks gh Implement djrk gSA Panel Class ds Object dk iz;ksx ge lkekU;r;k Container ij fLFkr fofHkUu GUI Components ds Layout dks Set djus ds fy, djrs gSaA Panel Class Applet Class dh Super Class gksrh gSA Panel Class ,d ,sls Window dks Represent djrk gS] ftlesa Title Bar, Menu Bar o Border ugha gksrh gSA pwafd bl Window dh dksbZ Border ugha gksrh gS vkSj blesa Title Bar o Menu Bar Hkh ugha gksrk gS] blhfy, ;s Window Screen ij fn[kkbZ ugha nsrk gSA tc ge fdlh Applet dks Appletviewer dk iz;ksx djds Run djrs gSa] rc gekjk Applet Program Appletviewer ds Title Bar o Border dks Use djrk gSA Panel Object esa fdlh Hkh vU; GUI Component dks Add djus ds fy, gesa add() Method dks Use djuk gksrk gSA ;s Method bl Panel Class esa Container Class ls Inherit gksrk gSA ,d ckj fdlh GUI Component dks Panel esa Add dj ysus ds ckn ml Component dks Panel esa Manually Position djus ;k Resize djus ds fy, ge Component Class ds setLocation(), setSize() ;k setBounds() Method dks Use dj ldrs gSaA

Window Class Window Class ,d Top-Level Window Create djrk gSA ,d Top-Level Window fdlh Hkh Container Object esa Store ugha gks ldrk gS] cfYd ,slk Object Directly Desktop ij Place gksrk gSA lkekU;r;k ge Window Class dk Object Create ugha djrs gSa] cfYd ge Frame Class dk Object Create djrs gSaA Frame Class ,d “Window” esa tks Hkh fo”ks’krk,a gksrh gSa] mu fo”ks’krkvksa dks Frame Class esa Encapsulate fd;k x;k gSA ;s Window Class dh ,d Sub Class gksrk gS vkSj blesa ,d Title Bar, ,d Menu Bar, ,d Border o Resizing Corner gksrs gSaA ;fn ge fdlh Applet Window ds vUnj dksbZ Frame Window Create djrs gSa] rks bl Frame Window ds Status Bar esa “Java Applet Window” Message Display gksrk gSA ;s Message User dks crkrk gS fd tks Window Display gks jgk gS] og Window ,d Applet }kjk Start gqvk gS uk fd Computer ij Run gksus okys fdlh Software }kjkA tc ,d Frame Window dks fdlh Program }kjk Create fd;k tkrk gS] uk fd fdlh Applet }kjk] rks og Frame Window ,d Normal Window gksrk gSA Canvas Class gkykafd Canvas Class Applet o Frame Window dh Hierarchy dk fgLlk ugha gS] fQj Hkh ;s ,d vU; izdkj dk Window gS] tks fd gekjs fy, dkQh mi;ksxh lkfcr gksrk gSA Canvas Class esa ,d ,slk Blank Window Encapsulate gksrk gS] ftl ij ge Drawing dj ldrs gSaA


Java in Hindi Frame Windows

Frame Window ,d ,slk Window gksrk gS] tks Stand-Alone Application Programs cukus ds fy, Use fd;k tkrk gSA gkykafd ge bldk iz;ksx Applet Window esa dj ldrs gSaA Applet Window ds ckn ;fn ge lcls T;knk fdlh Window dks Use djrs gSa] rks og Frame Window gh gksrk gSA

ge lkekU;r;k bu Windows dk iz;ksx fdlh Applet ds Child Window dks Create djus ds fy, djrs gSa] ;k fQj fdlh Application ds Main Window ;k Child Window dks Create djus ds fy, djrs gSaA tc ge Frame Window Create djrs gSa] rc gesa Standard Style dk Window izkIr gksrk gSA Frame Class esa nks Constructors gksrs gSa] ftuds Syntax fuEukuqlkj gSa% Frame() Frame(String title)

igyk Constructor ,d ,slk Window Create djrk gS] ftlds Title Bar ij dksbZ Title ugha gksrk gSA tcfd nwljs Constructor }kjk ge Create gksus okys Window dks ,d “Title” iznku dj ldrs gSaA /;ku nsa fd ge fdlh Frame ds Constructor esa ml Frame Window dh Size ;k Dimension dks Specify ugha dj ldrs gSa] cfYd Frame Window dh Size rc r; dj ldrs gSa] tc Window Create gks tkrk gSA fdlh Frame Window ds lkFk ge fofHkUu izdkj ds Methods dks Use dj ldrs gSaA fdlh Frame Window ds lkFk lcls T;knk Use fd, tkus okys dqN Methods dks ge fuEukuqlkj Describe dj ldrs gSa% setSize() Method – Specifying Window’s Dimension setSize() Method dk Window ds Dimension ;k Height o Width dks r; djus ds fy, fd;k tkrk gSA bl Method dk Signature fuEukuqlkj gksrk gS% void setSize(int newWidth, int newHeight) void setSize(Dimension newSize)

igys Method esa gesa Create gksus okys Window dh ubZ Size dks Specify djuk gksrk gSA ;fn ge pkgsa rks Height o Width ds Dimension dks ,d Dimension Object ds :i esa Hkh Specify dj ldrs gSa vkSj Window ds u, Dimension dks bl Method esa Argument ds :i esa Pass dj ldrs gSaA Dimensions dks Pixels dh la[;kvksa ds :i esa Specify fd;k tkrk gSA Window dh Current Size ;k Dimension izkIr djus ds fy, ge getSize() Method dks Use dj ldrs gSaA bl Method dk Signature fuEukuqlkj gksrk gS% Dimension getSize()

;s Method Window ;k fdlh Hkh vU; GUI Component dh Current Size dks Height o Width ds ,d Dimension Object ds :i esa Return djrk gSA setVisible() Method – Show / Hide Window or GUI Component


Java in Hindi fdlh Frame Window dks Create djus ds ckn mls Screen ij Display djus ds fy, gesa bl Method dks Use djuk gksrk gSA tc rd ge bl Method dks Call ugha djrs gSa] gekjk Frame Window Invisible gh jgrk gSA bl Method dk Signature fuEukuqlkj gksrk gS% void setVisible(boolean visibleFlag)

bl Method esa ;fn visibleFlag dk eku true gksrk gS] rks Component Visible gksrk gS] vU;Fkk Component Hidden jgrk gSA setTitle() Method – Setting Window’s Title fdlh Frame Window ds Title dks Change djus ds fy, ge setTitle() Method dk iz;ksx dj ldrs gSaA bl Method dk Signature fuEukuqlkj gksrk gS% void setTitle(String newTitle) newTitle og String gS] ftls ge Frame ds u, Title ds :i esa Define djuk pkgrs gSa

Closing a Frame Window tc ge fdlh Frame Window dks Use dj jgs gksrs gSa vkSj ml Frame Window dks Close djuk pkgrs gSa] rks gesa ml Frame Window dks Screen ls Remove djuk iMrk gSA fdlh Frame Window dks Screen ls Remove djus ds fy, ge setVisible(false) Method dks Call djrs gSaA fdlh Window dks Close djus ds fy, gesa windowClosing() Method dks Implement djuk gksrk gS] ftls WindowListener Interface esa Define fd;k x;k gSA fdlh Frame Window dks Close djus ds fy, bl method dks geus gekjs fiNys mnkgj.k esa Implement fd;k gSA gkykafd ge Frame Class dk Object Create djds ,d Frame Window Create dj ldrs gSa] ysfdu bl izdkj ds Window dk ge dksbZ fo”ks’k mi;ksx ugha dj ldrs gSaA mnkgj.k ds fy, bl izdkj ds Frame Window esa Generate gksus okys Events dks Receive o Process ugha fd;k tk ldrk gS] uk gh bl ij vklkuh ls fdlh Output dks Place fd;k tk ldrk gSA lkekU;r;k ge fdlh Frame Window dks Create djus ds fy, Frame Class dks Extend djrs gSaA Frame Class dh Sub Class Create djus ij ge Frame Class ds Methods dks Override dj ldrs gSa vkSj Event Handling dj ldrs gSa] ftlls gesa Create gksus okys Frame Window ij vf/kd Control izkIr gksrk gSA fdlh Applet Window esa fdlh Frame Window dks Create djuk dkQh ljy dke gksrk gSA lcls igys gesa Frame Class dks Inherit djuk gksrk gSA mlds ckn ge Applet ds fdlh Hkh Standard Method tSls fd init(), start(), paint(), stop() vkfn dks Override dj ldrs gSaA vUr esa WindowListener Interface dks Derived Frame Class esa Implement djuk gksrk gS vkSj windowClosing() Method dks Override djds mlesa setVisible(true) Method dks Call djds Window dks Screen ls Remove djuk gksrk gSA ,d ckj Frame Class dh Sub Class Create djus ds ckn ge ml Sub Class dk ,d Object Create dj ldrs gSaA tc ge ,slk djrs gSa] rc ,d Frame Window Create gksrk gS] ysfdu ;s Window Memory esa Create gksrk gS] blfy, Object Create djrs gh ;s Frame 517 Any Question or Suggestion, Just Discuss Here...

Java in Hindi Window gesa fn[kkbZ ugha nsrk gSA Frame Window dks Screen ij Visible cukus ds fy, gesa setVisible() Method dks Call djuk t:jh gksrk gSA tc ge setVisible() Method dks Call djds Frame Window dks Display djrs gSa] rc Frame Window viuh Default Size esa Display gksrk gSA Display gksus okys Frame Window dks Resize djus ds fy, ge setSize() Method dks Use dj ldrs gSaA

fuEu Applet Program esa geus Frame Class dks Inherit fd;k gSA fQj Applet ds init() Method esa bl Frame Window dk ,d Instance Create fd;k gSA Frame Window Create djus ds fy, Frame Class dk Constructor Call gksrk gS] tks fd ,d Standard Frame Window Create djrk gS] ftldk Title bl Constructor esa Argument ds :i esa Pass fd;k x;k gSA bl Applet Program esa geus Applet ds start() o stop() Method dks Child Frame Window dks Show o Hide djus ds fy, Use fd;k gSA tc ge Applet dks Terminate djrs gSa] rc Frame Window Hkh Automatically Memory ls Remove gks tkrk gSA Program // File Name : FrameInApplet.java import java.awt.*; import java.awt.event.*; import java.applet.*; class MyWindowAdapter extends WindowAdapter{ MyFrame source; public MyWindowAdapter(MyFrame frameWindow) this.source = frameWindow; }

}

{

public void windowClosing(WindowEvent wndEvnt){ source.setVisible(false); }

class MyFrame extends Frame{ MyFrame(String title){ super(title);

}

}

MyWindowAdapter adapter = new MyWindowAdapter(this); addWindowListener(adapter);

public void paint(Graphics g){ g.drawString("This Text is in Frame Window", 10, 35); }

public class FrameInApplet extends Applet{ Frame myFrameWindow;


Java in Hindi public void init(){ myFrameWindow = new MyFrame("My Frame Window");

}

myFrameWindow.setSize(250,150); myFrameWindow.setVisible(true); setSize(300, 200);

public void start(){ myFrameWindow.setVisible(true); } public void stop(){ myFrameWindow.setVisible(false); }

}

public void paint(Graphics g){ g.drawString("This Text is in Applet Window", 10, 40); }

Output

User Interface Control Fundamentals

AWT gesa fofHkUu izdkj ds User Interface Controls iznku djrk gS] ftudk iz;ksx djds ge GUI User Interface Create dj ldrs gSaA AWT dh Classes dk iz;ksx djds ge Menu o Menu Bar Hkh Design dj ldrs gSaA ge AWT ls Dialog Box o File Dialog Box Components Hkh Create dj ldrs gSa] ftlesa gesa ,d vyx rjhds ls Event Handling dk

dke djuk iMrk gSA

User Interface Controls mu Objects dks dgrs gSa] tks User dks Program ls Graphically Interact djus dh lqfo/kk iznku djrs gSaA mnkgj.k ds fy, Push Button ,d Common :i ls Use fd;k tkus okyk User Interface Control gSA

tkok esa Layout Manager ,d ,slk Control gksrk gS] tks fofHkUu izdkj ds User Interface Controls dks fdlh Application ds Frame Window ij ;k Applet ds Canvas ij fofHkUu izdkj ds Objects dks Position o Manage djus dk dke djrk gSA vr% ge dg ldrs gSa fd


Java in Hindi fdlh Window dk Appearance bl ckr ij fuHkZj djrk gS fd geus fdlh Window ij fdu Controls dks fdl izdkj ds Layout Managers dk iz;ksx djrs gq, Place fd;k gSA vU; Controls ds vykok ,d Frame Window ds lkFk fdlh Menu Bar dks Hkh Attach fd;k tk ldrk gSA Menu Bar dk gj Option ,d u, Drop Down Menu dks Display djrk gS] ftlesa fLFkr fofHkUu Options dks User Choose dj ldrk gSA ,d Menu Bar gesa”kk fdlh Window ds Top ij gh Position gksrk gSA Menu Bar ds fofHkUu Options Hkh vU; GUI Components dh rjg gh dke djrs gSaA gkykafd ge fofHkUu izdkj GUI Components dks Container esa Manually Position dj ldrs gSa] ysfdu ,slk djuk dkQh dfBu dke gksrk gSA Layout Manager bl dke dks vklkuh ls Automatic rjhds ls dj nsrk gSA

Adding and Removing Controls

fdlh Window esa dksbZ GUI Component Add djus ds fy, gesa lcls igys fdlh Control dks Create djuk gksrk gSA fQj ml Control dks Container Class esa Define fd, x, add() Method dk iz;ksx djds Window esa Add djuk gksrk gSA add() Method dbZ rjg ls Overloaded gSA bl Method dk General Syntax fuEukuqlkj gksrk gS% Component add(Component compObj)

bl Syntax esa compObj ml Control dk ,d Instance gksrk gS] ftls ge Window ij Add djuk pkgrs gSaA bl Method ls Add fd, x, Component Object dk ,d Reference Return gksrk gSA tc ge fdlh Window esa fdlh Component dks Add dj nsrs gSa] rks tc Hkh ml Component okyk Parent Window Display gksrk gS] ;s Control Hkh Display gksrk gSA dbZ ckj ge fdUgha ifjfLFkfr;ksa esa fdlh Control dks Window ls Remove djuk pkgrs gSaA ml fLFkfr esa gesa remove() Method dks Call djuk gksrk gSA bl Method dks Hkh Container Class esa gh Define fd;k x;k gS vkSj bl Method dk General Syntax fuEukuqlkj gksrk gS% void remove(Component compObj)

bl Syntax esa Hkh compObj ml Object dks Refer djrk gS] ftls gesa Window ls Remove djuk gksrk gSA fdlh Window ij Placed lHkh Components dks Window ls Remove djus ds fy, ge removeAll() Method dks Call dj ldrs gSaA Labels ;s ,d ,slk Control gS] tks fdlh izdkj dk dksbZ Event Generate ugha djrk gSA ;s Control Window esa fdlh Label ;k Message dks Display djus ds fy, Use fd;k tkrk gSA blds rhu Constructors fuEukuqlkj gksrs gSa% Label() Label(String str) Label(String str, int how)


Java in Hindi ;fn ge igys Constructor ds vuqlkj dksbZ Label Create djrs gSa] rks Add gksus okyk Control ,d Blank Label gksrk gSA nwljs Constructor esa str og String gS] ftls Label }kjk Display djuk gksrk gSA tcfd rhljs Constructor ds how Argument }kjk ge ;s r; djrs gSa fd Label esa Display gksus okyh String dk Alignment fdl izdkj dk gksxkA bl Argument esa Label.LEFT, Label.CENTER ;k Label.RIGHT esa ls dksbZ eku gksrk gSA Label esa fn[kkbZ nsus okyh String dks ge setText() Method dk iz;ksx djds Set ;k Change dj ldrs gSaA blh rjg ls Label ds Current Text dks izkIr djus ds fy, ge getText() Method dks Use dj ldrs gSaA bu Methods dk Syntax fuEukuqlkj gksrk gSa% void setText(String str) String getText() setText() Method esa str Argument u, Label dks Specify djrk gS] tcfd getText() Method esa Label dk Current Label Return gksrk gSA Label ds Alignment dks fQj ls Set djus ds fy, ge setAlignment() Method dks Use dj ldrs gSaA tcfd Current Alignment dks izkIr djus ds fy, ge getAlignment() Method dks Use dj ldrs gSaA bu nksuksa Methods ds Syntax fuEukuqlkj gksrs gSa% void setAlignment(int how) int getAlignment()

;gka how Argument esa Label.LEFT, Label.CENTER ;k Label.RIGHT esa ls dksbZ gh dksbZ eku gksrk gSA Buttons

Push Button fdlh Hkh Window esa Generally Use fd;k tkus okyk lcls Common Component gSA Push Button ,d ,slk Component gksrk gS] ftlesa ,d Label gksrk gS vkSj ;s Control User ds Interaction ij dksbZ Event Generate djus esa l{ke gksrk gSA Push Buttons Button Class ds Objects gksrs gSaA Button Class esa fuEukuqlkj nks Constructors

gksrs gSa%

Button() Button(String str)

igyk Constructor ,d Empty String okyk Button Object Create djrk gS] tcfd nwljs Constructor esa Button ij fn[kkbZ nsus okyk Label String ds :i esa Specify fd;k tkrk gSA ,d Button dks Create djus ds ckn ge ml Button dk Label setLabel() Method dk iz;ksx djds Set ;k Change dj ldrs gSaA tcfd fdlh Button dk Label izkIr djus ds fy, gesa getLabel() Method dks Use djuk gksrk gSA bu nksuksa Methods ds Syntax fuEukuqlkj gksrs gSa% void setLabel(String str) String getLabel()

tc gesa fdlh Button dk Label Change djuk gksrk gS] rc ge str esa og u;k Label Specify djrs gSa] ftls gesa Button ij Display djuk gksrk gSA


Java in Hindi Button Object gesa”kk ,d Action Event Generate djrk gSA bl Event dks Handle djus ds fy, Event dks Button ls Registered o igys ls Defined fdlh Listener Object esa Hkstuk gksrk gSA ftrus Hkh Listeners dks Button ls Registered fd;k x;k gksrk gS] mu lHkh Listeners esa ActionListener Interface dks Implement fd;k x;k gksrk gSA

bl Interface esa actionPerformed() Method dks Define fd;k tkrk gSA ;s Method rc Invoke gksrk gS] tc bl Listener ls Registered fdlh Button dks Push fd;k tkrk gSA bl Method esa ActionEvent Class dk ,d Object Argument ds :i esa Pass fd;k tkrk gSA bl ActionEvent Object esa Event Generate djus okys Button dk o Button ij fLFkr Label dk nksuksa dk Reference gksrk gSA bu nksuksa esa ls fdlh Hkh Value dk iz;kssx djds ge ;s irk yxk ldrs gSa] fd fdl Button ls Event Generate gqvk gSA Check Boxes ;s ,d ,slk Control gksrk gS tks fdlh Option dks ON ;k OFF djus dk dke djrk gSA ;s ,d NksVs ls Box dh rjg gksrk gS] ftl ij Click djus ij mlesa Check Mark Display gksus yxrk gSA tc fdlh Check Box esa Check Mark Display gksrk gS] rc og Control ON Position esa gksrk gSA Check Box ds lkFk ,d Label Associated jgrk gS] tks Check Box ds Option dks Represent djrk gSA Check Box dh fLFkfr dks Change djus ds fy;k ;kuh Option dks ON ;k OFF djus ds fy, gesa Check Box ij Click djuk gksrk gSA ge Check Boxes dks ,d Group ds :i esa Hkh Use dj ldrs gSa vkSj Single Check Box ds :i esa Hkh Use dj ldrs gSaA Check Boxes Checkbox Class ds Objects gksrs gSaA tc Check Box Checked gksrk gS] rc og True Condition dks Represent djrk gS] tcfd Unchecked fLFkfr esa og False Condition n”kkZrk gSA ,d Check Box ds fuEukuqlkj ikap Constructors gksrs gSa% Checkbox() Checkbox(String str) Checkbox(String str, boolean on) Checkbox(String str, boolean on, CheckboxGroup cbGroup) Checkbox(String str, CheckboxGroup cbGroup, boolean on)

igyk Constructor ,d ,slk Check Box Create djrk gS] ftldk Label Initially Blank gksrk gSA nwljk Constructor ,d ,slk Check Box Create djrk gS] ftlds lkFk og Label Associated jgrk gS] tks ge Argument ds :i esa Constructor esa Specify djrs gSaA rhljk Constructor ,d ,slk Check Box Create djrk gS] tgka ge nwljs Argument esa true Specify djds ,d Checked Check Box izkIr dj ldrs gSaA pkSFks vkSj ikapos Constructor }kjk ,d ,slk Check Box Create gksrk gS] ftldk uke str }kjk Specify fd;k x;k gksrk gS vkSj Check Box ds Group dks cbGroup Argument }kjk Specify fd;k tkrk gSA ;fn Create fd;k tkus okyk Check Box fdlh Group dk Part uk gks] rks cbGroup Argument esa null Specify djuk gksrk gSA Boolean Variable on }kjk ;s Specify fd;k tkrk gS] fd Create gksus okyk Check Box Checked gksxk ;k ughaA Check Box dh Current State dk irk yxkus ds fy, gesa getState() Method dks Use djuk gksrk gS] tcfd fdlh Check Box dh State dks Change djus ds fy, gesa setState()


Java in Hindi Method dks Use djuk gksrk gSA fdlh Check Box ds lkFk Associated Current Label dks izkIr djus ds fy, ge getLabel() Method dks Use dj ldrs gSa] tcfd Check Box ds Label dks fQj ls Set djus ds fy, gesa setLabel() Method dks Use djuk gksrk gSA bu pkjksa Methods ds Syntax fuEukuqlkj gksrs gSa% boolean getState() void setState(boolean on) String getLabel() void setLabel(Sting str)

;gka] ;fn ge on dk eku true j[krs gSa] rks Check Box Checked gks tkrk gS] tcfd ;fn bldk eku false gks] rks Check Box Clear gks tkrk gSA str esa Pass dh tkus okyh String Check Box ls Associated Label dks Change dj nsrk gSA ftruh ckj Hkh ge fdlh Check Box dks Select ;k Deselect djrs gSa] ,d Item Event Generate gksrk gSA ;s Item Event ml Listener ij Event Handling ds fy, Hkstk tkrk gS] ftls Check Box ls Register fd;k x;k gSA bl Listener esa ItemListener Interface dks Implement fd;k x;k gksrk gSA bl Interface esa itemStateChanged() uke dk ,d Method Implement fd;k tkrk gS vkSj ;s Method rc Invoke gksrk gS] tc fdlh Check Box dks Select ;k Deselect fd;k tkrk gSA Generate gksus okys ItemEvent Object dks Handle djus ds fy, Argument ds :i esa bl Method esa Pass fd;k tkrk gSA Check Box dks Select ;k Deselect djus ij Generate gksus okys bl ItemEvent Object es bl ckr dh tkudkjh gksrh gS] fd Item dks Select fd;k x;k gS ;k Deselect fd;k x;k gSA

Choice Controls Choice Class dk iz;ksx Options dh ,d Pop-up List Create djus ds fy, fd;k tkrk gS] ftlesa ls User fdlh ,d Option dks Choose dj ldrk gSA ;kuh Choice dks ge ,d Menu dh rjg eku ldrs gSa] ftlesa cgqr lkjs Options gksrs gSa] ysfdu ge ,d le; esa dsoy ,d gh Option dks Choose dj ldrs gSaA Choice Control esa ge ftl Item dks Select djrs gSa] ogh Item Window ij Display gksrk gS] Choice Control ds “ks’k Items Hide gks tkrs gSaA bl Control dks Drop-Down List Control Hkh dgk tkrk gSA tc User bl Control ij Click djrk gS] rks bl Control dh List ds lHkh Options Pop-up gks tkrs gSaA bl List esa ls User ftl Item dks Select djrk gS] dsoy ogh Item Choice Control esa Highlight gksus yxrk gSA List esa ftrus Hkh Items Display gksrs gSa] os lHkh Items ,d Left-Justified Label String gksrs gSa vkSj ;s mlh Øe esa Choice Control esa Display gksrs gSa] ftl Øe esa bUgsa Choice Control esa Add fd;k x;k gksrk gSA Choice Class esa dsoy ,d gh Default Constructor gksrk gS] ftldk Syntax fuEukuqlkj gS% void add(String itemName)

bl Constructor esa itemName og Option gS] ftls ,d Label ds :i esa Choice Control esa Add djuk gSA Choice Control esa ,d ls T;knk Items dks Add djus ds fy, gesa bl


Java in Hindi add() Method dks dbZ ckj Call djuk iMrk gS vkSj ge ftl Øe esa add() Method dks Call djds Items dks Add djrs gSa] os Items Choice Control esa mlh Øe esa fn[kkbZ nsrs gSaA

;s irk djus ds fy, fd Choice Control esa Currently fdl Item dks Select fd;k x;k gS] ge getSelectedItem() ;k getSelectedIndex() Method dks Use dj ldrs gSaA bu nksuksa Methods dk Syntax fuEukuqlkj gksrk gS% String getSelectedItem() int getSelectedIndex() getSelectedItem() Method Currently Selected Item dk uke ,d String Object ds :i esa Return djrk gSA tcfd getSelectedIndex() Method Currently Selected Item dk Index Number Return djrk gSA Choice Control esa igyk Item gesa”kk Index Number 0 ij gksrk gS] ;kuh Choice Control ds Index Numbers dh Counting gesa”kk 0 ls “kq: gksrh gSA Choice Control esa tks Hkh igyk Item Add fd;k tkrk gS] og Item Default :i ls Selected

jgrk gSA

fdlh Choice Object esa fLFkr dqy Items dh la[;k Kkr djus ds fy, ge getItemCount() Method dks Use dj ldrs gSaA blh rjg ls Choice Control ds fdlh Item dks Select djus ds fy, ge select() Method dks Use dj ldrs gSa] ftlesa Argument ds :i esa ge Item dk Index Number ns ldrs gSa] ;k fQj ,d String ds :i esa Item ds uke dks Specify dj ldrs gSaA bu Methods dk Syntax fuEukuqlkj gksrk gS% int getItemCount() void select(int index) void select(String itemName) getItem() Method esa Argument ds :i esa fdlh Item dk Index Number Specify djds ge ml Item dk uke String Object ds :i esa izkIr dj ldrs gSaA bl Method dk Syntax

fuEukuqlkj gksrk gS%

String getItem(int index)

ge ftruh ckj fdlh Choice Control ds fdlh Item dks Select djrs gSa] ,d ItemEvent Generate gksrk gSA ;s Event ,d ,sls Listener ij Hkstk tkrk gS] ftls igys gh Choice Control Object ls Register dj fn;k x;k gksrk gSA bl Listener esa ItemListener Interface dks Implement fd;k x;k gksrk gSA bl Interface esa itemStateChanged() uke dk ,d Method Implement fd;k x;k gksrk gSA tc ItemEvent Generate gksrk gS] rc ;s Method Execute gksrk gS vkSj Generate gksus okyk ItemEvent Object dks Argument ds :i esa izkIr djrk gSA List Control List Class gesa ,d ,sls Scrollable Items dh List Provide djrk gS] ftlesa ge ,d ls T;knk Items dks Select dj ldrs gSaA Choice Control esa ge ,d le; esa dsoy ,d gh Selected Item dks Display dj ldrs gSa] tcfd bl Control esa ge ,d ls T;knk List Items dks


Java in Hindi Display dj ldrs gSaA List Class gesa rhu Constructors Provide djrk gS] tks fuEukuqlkj

gSa%

List() List(int numRows) List(int numRows, boolean multipleSelect)

bu Constructors esa tks igyk Constructor gS] og Constructor gesa ,d le; esa dsoy ,d gh Item Select djus dh lqfo/kk nsrk gSA nwljk Constructor gesa mrus Rows Window ij gesa”kk Display djrk gS] ftruh la[;k ge numRows Argument esa Specify djrs gSaA List ds “ks’k Items Scrollable gksrs gSa] ftUgsa Scroll djds ns[kk tk ldrk gSA rhljs Constructor esa ;fn ge multipleSelect Boolean Variable esa true Set djrs gSa] rks ge List Control esa ,d ls T;knk Items dks Select dj ldrs gSaA List esa fdlh Item dks Select djus ds fy, ge fuEu esa ls fdlh add() Method dks Call dj ldrs gSa% void add(String itemName) void add(String itemName, int index)

bu Syntaxes esa itemName og String gS] ftls ge List Item ds :i esa List Object esa Add djuk pkgrs gSaA tc gesa fdlh Item dks List ds fdlh Specific Index Number ij Add djuk gksrk gS] rc nwljs Argument ds :i esa ge og Index Number Specify dj nsrs gSa] tgka ij ge u, Item dks Add djuk pkgrs gSaA ;fn ge fdlh Item dks List ds vfUre Item ds :i esa Specify djuk pkgsa] rks gesa Index Number ds :i esa -1 nsuk gksrk gSA tc ge ,slh Lists Create djrs gSa] ftuesa dsoy ,d gh Item dks Select fd;k tk ldrk gS] ,slh List ds fdlh List dks Select djus o Selected Item dks izkIr djus ds fy, ge getSelectedItem() o getSelectedIndex() Methods dks mlh rjg ls Use dj ldrs gSa] ftl rjg ls bUgsa Choice Control ds lkFk Use djrs gSaA ;fn fdlh List esa fdlh Item dks Select uk fd;k x;k gks] rks getSelectedItem() Methods null Return djrk gS tcfd fdlh Multiple Selection okyh List esa tc ,d ls T;knk Items dks Select fd;k x;k gks ;k fdlh Item dks Select uk fd;k x;k gks] rks getSelectedIndex() Method -1 Return djrk gSA ,slh Lists ftlesa ,d ls T;knk Items dks Select fd;k tk ldrk gS] gesa fuEu esa ls fdlh Format okys getSelectedItem() ;k getSelectedIndex() Method dks Use djuk pkfg,% String[] getSelectedItem() int[] getSelectedIndex()

;gka igyk Method Selected Items dh Strings dk ,d Array Return djrk gS] tcfd nwljk Method Selected Items ds Index Numbers ds Integers dk ,d Array Return djrk gSA fdlh List Object esa fLFkr dqy Items dh la[;k Kkr djus ds fy, ge getItemCount() Method dks Use dj ldrs gSaA blh rjg ls List Control ds Currently Selected Item dks Set djus ds fy, ge select() Method dks Use dj ldrs gSa] ftlesa Argument ds :i esa ge Item dk Index Number ns


Java in Hindi ldrs gSa] ;k fQj ,d String ds :i esa Item ds uke dks Specify dj ldrs gSaA bu Methods dk Syntax fuEukuqlkj gksrk gS% int getItemCount() void select(int index) void select(String itemName) getItem() Method esa Argument ds :i esa fdlh Item dk Index Number Specify djds ge ml Item dk uke String Object ds :i esa izkIr dj ldrs gSaA bl Method dk Syntax


String getItem(int index) List ls Generate gksus okys Events dks Handle djus ds fy, gesa Action Listener Interface dks Implement djuk gksrk gSA tc Hkh fdlh List Item ds fdlh Item dks Double Click fd;k tkrk gS] ,d ActionEvent Object Generate gksrk gSA ActionListener Interface dk getActionCommand() Method dk iz;ksx djds ge Currently Selected Item dk uke

izkIr dj ldrs gSaA

lkFk gh ge fdlh List Control esa ftruh ckj Hkh fdlh Item dks Select ;k Deselect djrs gSa] ,d ItemEvent Object Generate gksrk gSA ItemListener Interface ds getStateChange() Method dks Use djds ge ;s irk dj ldrs gSa fd List esa fdlh Item dks Select ;k Deselect fd;k x;k gS ;k ughaA tcfd getItemSelectable() Method ml Object dk Reference Return djrk gS] ftlus Event Trigger fd;k gksrk gSA

Scroll Bars Scrollbars dk iz;ksx fdlh Specified Minimum o Maximum Values ds chp dh fdlh Value dks Select djus ds fy, fd;k tkrk gSA Scrollbars dks Horizontally o Vertically nksuksa rjhdksa ls Organize fd;k tk ldrk gSA ,d Scrollbar okLro esa cgqr lkjs Individual Parts dk Composite :i gksrk gSA blds nksuksa rjQ ,d Arrow gksrk gS] ftl ij Click djds ge Scrollbar dh Value dks Current Value ls Increase ;k Decrease djrs gSaA Scrollbar dh Current Value mldh Minimum o Maximum Value ls Related gksrh gS] ftls Scrollbar ds Slider ls Represent fd;k tkrk gSA Slider Box dks User viuh t:jr ds vuqlkj Scroll djds ubZ Position ij Change dj ldrk gSA

,slk djus ij Scrollbar ubZ Value dks Represent djus yxrk gSA tc User dks Default Increment Value 1 ls vf/kd Scroll djuk gksrk gS] rc og Scrollbar ds Slider esa Click dj ldrk gSA bl Action dks lkekU;r;k Page Up o Page Down ds :i esa le>k tk ldrk gSA tkok esa Scrollbars dks Scrollbar Class esa Encapsulated fd;k x;k gSA bl Class esa rhu Constructs gSsa] tks fuEukuqlkj gksrs gSa% Scrollbar() Scrollbar(int style) Scrollbar(int style. int initialValue, int thumbSize, int min, int max)


Java in Hindi igyk Constructor ,d Vertical Scrollbar Create djrk gSA nwljk Constructor Scrollbar ds Direction dks Specify djrk gSA ;fn style Argument esa Scrollbar.VERTICAL Constant eku gks] rks Vertical Scrollbar Create gksrk gS] tcfd blesa Scrollbar.HORIZONTAL Constant eku gksus ij Horizontal Scrollbar Create gksrk gSA rhljs Constructor esa Scrollbar dh Initial Value dks initialValue Argument esa Specify fd;k tkrk gSA Slider esa fn[kkbZ nsus okys Thumb dh Size dks thumbSize Argument esa Specify fd;k tkrk gS vkSj Scrollbar dh Minimum o Maximum Values dks min o max uke ds Argument }kjk Specify fd;k tkrk gSA tc ge bu esa ls fdlh Constructor dks Use djds Scrollbar Create djrs gSa] rc gesa setValues() Method dks Use djds Scrollbar ds Parameters dks Set djuk gksrk gSA bl Method dk General Syntax fuEukuqlkj gksrk gS% void setValues(int initialValue, int thumbSize, int min, int max) Scrollbar dh Current Values dks izkIr djus ds fy, ge getValue() Method dks Call dj ldrs gSaA ;s Method Scrollbar dh Current Settings dks Return djrk gSA tcfd Current Value dks Set djus ds fy, ge setValue() Method dks Use dj ldrs gSaA bu nksuksa Methods dk Syntax fuEukuqlkj gksrk gS% int getValue() void setValue(int newValue)

bl Method esa newValue og eku gS] ftls Scrollbar ds fy, Specify fd;k tkrk gSA tc ge dksbZ Value Set djrs gSa] rks Scrollbar dk Slider Box ml u, eku dks Represent djrs gq, Slider esa u, LFkku ij Place ;k Set gks tkrk gSA Scrollbar dh Minimum o Maximum Values dks izkIr djus ds fy, ge getMinimum() o getMaximum() Method dks Use dj ldrs gSa] ftudk Syntax fuEukuqlkj gksrk gS% int getMinimum() int getMaximum() Scrollbar esa Increase ;k Decrease gksus okyh By Default Value 1 gksrh gS] tks ,d Line dks Up ;k Down djrh gSA ge bl Incrementing Value dks setUnitIncrement() Method dk iz;ksx djds Change dj ldrs gSaA tcfd Page-Up o Page-Down dh By Default Value 10 gksrh gS] ftls Change djus ds fy, ge setBlockIncrement() Method dks Use dj ldrs gSaA ;s Methods fuEukuqlkj gksrs gSa% void setUnitIncrement(int newIncr) void setBlockIncrement(int newIncr) Scrollbar }kjk Trigger gksus okys Events dks Handle djus ds fy, gesa AdjustmentListener Interface dks Implement djuk gksrk gSA tc Hkh User Scrollbar ls Interact djrk gS] ,d AdjustmentEvent Object Generate gksrk gSA bldk getAdjustmentType() Method dk iz;ksx djds ge ;s tku ldrs gSa fd fdl izdkj dk AdjustmentEvent Generate gqvk gSA Generate gksus okys AdjustmentEvent fuEu izdkj

ds gks ldrs gSa%


Java in Hindi BLOCK_DECREMENT BLOCK_INCREMENT TRACK UNIT_DECREMENT UNIT_INCREMENT

Page-Down Page-Up Absolute Tracking Event Line-Down Line-Up

TextField Control TextField Class ls ge ,d Single Line Text Entry Area Create dj ldrs gSa] ftls Edit Control Hkh dgrs gSaA TextField User dks Strings dks Enter djus o mls Modify ;k Edit djus dh lqfo/kk nsrk gSA bl Control esa fy[ks x, Texts dks Mouse ls Select fd;k tk ldrk gS vkSj ml Text ij Cut, Copy o Paste tSls Operations Perform fd, tk ldrs gSaA TextField Class TextComponent Class dh Sub Class gSA TextField Class esa fuEu Constructors dks Define fd;k x;k gS% TextField() TextField(int numChars) TextField(String str) TextField(String str, int numChars)

igyk Constructor ,d Default Text Field Create djrk gSA nwljk TextField Create djrk gS] ftldh Size numChars Argument esa Characters ds cjkcj gksrh gSA rhljk Constructor str Argument esa Characters dks Create gksus okys Default TextField esa Fill dj Constructor numChars ds cjkcj Characters dks Hold dj ldus okyk djrk gS vkSj mlesa str Argument esa fn, x, String dks Fill dj nsrk gSA

Constructor ,slk Specify fd, x, Specify fd, x,

nsrk gS vkSj pkSFkk TextField Create

TextField Class o bldh Super Class TextComponent Class nksuksa TextField dks fofHkUu rjhdksa ls Use djus ls lEcaf/kr fofHkUu izdkj ds Methods Provide djrs gSaA TextField esa Currently Specify fd, x, Characters dh String dks Return djus ds fy, ge getText() Method dks Use djrs gSa] tcfd TextField esa fdlh Text dks Fill djus ds fy, gesa setText() Method dks Use djuk gksrk gSA bu nksuksa Methods dk Syntax fuEukuqlkj gksrk gS% String getText() void setText(String str) User TextField ds fdlh fo”ks’k Text dks Mouse ls Select dj ldrk gSA lkFk gh ge Program ds Run Time esa Hkh TextField dh String ds fdlh fgLls dks select() Method dk iz;ksx djds Select dj ldrs gSaA TextField esa Currently Selected Text dks izkIr djus ds fy, ge getSelectedText() Method dks Use dj ldrs gSaA bu Methods dk Syntax


String getSelectedText() void select(int startIndex, int endIndex)


Java in Hindi getSelectedText() Method dks ge TextField esa Currently Select fd, x, Text dks izkIr djus ds fy, Use dj ldrs gSaA tcfd select() Method startIndex ls endIndex-1 rd ds Characters dks Select djus dk dke djrk gSA ge setEditable() Method dk iz;ksx djds ;s r; dj ldrs gSa fd fdlh TextField ds Text Edit gks ldrs gSa vFkok ughaA tcfd dksbZ TextField Editable gS vFkok ugha bl ckr dk irk yxkus ds fy, ge isEditable() Method dks Use dj ldrs gSaA ;s nksuksa Methods fuEukuqlkj gksrs gSa% boolean isEditable() void setEditable(boolean canEdit)

;fn fdlh TextField ds Text dks Change fd;k tk ldrk gks] rks isEditable() Method true Return djrk gS] tcfd ;fn dksbZ TextField Read Only Mode esa gks] rks ;s Method false Return djrk gSA tcfd setEditable() Method esa ;fn ge true Pass djrs gSa] rks bldk eryc gksrk gS] fd TextField ds Text dks Edit fd;k tk ldrk gS] tcfd ;fn ge blesa Argument ds :i esa false Pass dj nsa] rks bldk eryc ;s gS fd ge bl TextField ds Text dks Edit, Alter ;k Modify ugha dj ldrs gSaA dbZ ckj gesa ,slh t:jr gksrh gS] fd User fdlh TextField esa tks Text Enter djrk gS] og Text fn[kkbZ ugha nsuk pkfg,A tSls fd User fdlh TextField esa ;fn Password Input djrk gS] rks og Password fn[kkbZ ugha nsuk pkfg,A User fdlh TextField esa tks Characters Input djrk gS] ;fn ge mu Texts dks TextField esa Display djokus ls jksduk pkgrs gSa] rks gesa setEchoChar() Method dks Use djuk gksrk gSA ;s Method ml Single Character dks Specify djrk gS] ftls TextField esa Enter djrs le; Display fd;k tkuk gksrk gSA ;s Method fuEukuqlkj gksrk gS% void setEchoChar(char ch)

bl Method esa ;fn ge Argument ch esa “ * ” Specify dj nsa] rks User bl TextField esa dksbZ Hkh Character Input djs] bl TextField esa og Character “ * ” dh Series ds :i esa gh fn[kkbZ nsrk gSA ;fn gesa ;s irk djuk gks fd dksbZ TextField bl Method ls Set fd;k x;k gS ;k ugha] rks ge ;s tkudkjh izkIr djus ds fy, echoCharIsSet() Method dks Use dj ldrs gSaA ;s Method fuEukuqlkj gksrk gS] boolean echoCharIsSet()

;fn gesa ;s tkuuk gks fd fdlh TextField dks fdl Character ls Set fd;k x;k gS] rks ge getEchoChar() Method dks Use dj ldrs gSa] tks fd fuEukuqlkj gksrk gS% char getEchoChar()

lkekU;r;k TextField ls dke djus ls lEcaf/kr fofHkUu izdkj ds Functions TextField Class esa gh Define fd, x, gSa] blfy, blds lkFk dke djus ds fy, gesa fdlh Interface dks Implement djus dh t:jr ugha gksrh gSA ysfdu ;fn ge pkgrs gSa fd Enter Key Press djus


Java in Hindi ij Focus fdlh nwljs TextField ij Move gks] rks blds fy, gesa Generate gksus okys ActionEvent Object dks Handle djuk gksrk gSA

TextArea Control dbZ ckj gekjk dke Edit Control dh Single Line esa ugha gks ikrk gSA bl fLFkfr esa gesa ,sls Control dh t:jr gksrh gS] ftlesa ge ,d ls T;knk Lines dk Text Type dj ldsaA tkok ds AWT esa bl dke dks iwjk djus okys Control dks TextArea Control dgk tkrk gSA bldh Class esa fuEukuqlkj ikap Constructors gksrs gSa% TextArea() TextArea(int numLines, int numChars) TextArea(String str) TextArea(String str, int numLines, int numChars) TextArea(String str, int numLines, int numChars, int sBars)

bu Constructors esa numLines Arguments TextArea Control dh Height dks Lines dh la[;k ds :i esa Specify djrk gS] tcfd numChars Argument TextArea dh Width dks Characters dh la[;k ds :i esa Specify djrk gSA tc gesa fdlh TextArea dks Create djrs gh mlesa dqN Text Specify ;k Fill djuk gksrk gS] rc gesa og Text str Argument ds :i esa Constructor esa Specify djuk gksrk gSA ikapos Constructor ds vfUre Argument sBars esa ge fuEu esa ls dksbZ Constant eku iznku dj ldrs gSa] tks TextArea ds lkFk Scrollbars dks Display djus ls lEcaf/kr gksrk gS% SCROLLBARS_BOTH SCROLLBARS_NONE SCROLLBARS_HORIZONTAL_ONLY SCROLLBARS_VERTICAL_ONLY TextArea Class Hkh TextComponent Class dh ,d Sub Class gSA blfy, ;s Hkh getText(), setText(), getSelectedText(), select(), isEditable() o setEditable() Methods dks TextField Control dh rjg gh Support djrk gSA buds vykok TextArea Class esa fuEu Methods vkSj Define fd, x, gSa% void append(String str) void insert(String str, int index) void replaceRange(String str, int startIndex, int endIndex ) append() Method str esa Specify dh xbZ String dks Current Text ds End esa Append dj nsrk gSA insert() Method str esa Specified String dks Specify fd, x, Index Number ij Insert dj nsrk gSA

tcfd fdlh TextArea Control esa Select fd, x, Text ds LFkku ij str esa Specified u, Text dks Replace djus ds fy, replaceRange() Method dks Use fd;k tk ldrk gSA ;k ge ,slk Hkh dg ldrs gSa fd str esa Stored String dks startIndex ls endIndex-1 rd ds Text ds LFkku ij Replace dj fn;k tkrk gSA TextArea Controls ds Events dks Hkh gesa


Java in Hindi vyx ls Handle djus dh t:jr ugha gksrh gSA ;s Control dsoy LOST_FOCUS Event gh Generate djrs gSaA

GOT_FOCUS

o

CheckboxGroup Control bl Control dks lkekU;r;k Radio Buttons Hkh dgrs gSaA Radio Buttons dk iz;ksx cgqr lkjs Options esa ls fdlh ,d Option dks Select djus ds fy, fd;k tkrk gSA bl Control dks Create djus ds ckn gesa bl Control esa vko”;drkuqlkj Options dks Add djuk gksrk gSA bls Create djus ds fy, ge fuEu Constructor Statement dk iz;kssx dj ldrs gSa% CheckboxGroup radioGroup = new CheckboxGroup() CheckboxGroup Object Create djus ds ckn gesa ,d Checkbox Create djuk gksrk gS] ftlds Constructor ds nwljs Argument ds :i esa gesa bl radioGroup Object dk Reference nsuk gksrk gSA ;s dke ge fuEukuqlkj Statement }kjk dj ldrs gSa% check1 = new Checkbox(“C Language”, radioGroup, true); check2 = new Checkbox(“C++ Language”, radioGroup, true); check3 = new Checkbox(“Java Language”, radioGroup, true); check4 = new Checkbox(“Visual Basic Language”, radioGroup, true);

mijksDr Code Segment pkj Radio Buttons Create djrk gS vkSj ;s lHkh Radio Buttons ,d gh Group radioGroup Object ds lnL; gksrs gSaA ge ,d le; esa bl Group ds fdlh ,d gh Option dks Select dj ldrs gSaA bu Radio Buttons dks fdlh Container esa Add djus ds fy, gesa fuEukuqlkj add() Method dks Use djuk gksrk gSA add(check1) add(check2) add(check3) add(check4) radioGroup Object ls Generate gksus okys Events dks Handle djus ds fy, Hkh gesa mlh Process dks Use djuk gksrk gS] ftl Process dk iz;ksx gesa fdlh Checkbox ls Generate gksus okys Events dks Handle djus ds fy, djuk gksrk gSA

Layout Manager Layout Manages ,d fo”ks’k izdkj ds Objects gksrs gSa tks ;s r; djrs gSa fd Application ;k Applet ds Window esa fofHkUu izdkj ds Components fdl izdkj ls Organize gksaxsA tc ge fdlh Applet ;k Application dks Create djrs gSa] rc tkok Automatically ,d Default Layout Manager Create djrk gS vkSj gekjs Applet ;k Application dks og Default Layout Manager Object Assign dj nsrk gSA lkekU;r;k ;s Default Layout Manager Flow Layout Object gksrk gSA geus blh v/;k; esa ns[kk gS fd dqy ikap rjg ds Containers gksrs gSa] ftuesa ls Panel Hkh ,d izdkj dk Container gSA ysfdu ;s ,d ,slk Container gS] tks Visually Display ugha gksrk gSA


Java in Hindi blfy, bl Container dk iz;ksx lkekU;r;k fofHkUu izdkj ds Controls ds Group dks vU; Visually Display gksus okys Containers ij Organize (Localize and Sized) djus ds fy, fd;k tkrk gSA tc ge fofHkUu Components dks Applet ;k fdlh vU; Container ij Place djrs gSa] rc ftl rjhds ls ;s fofHkUu Controls Screen ij ;k Applet ij Organize gksrs gSa] muds Organize gksus dk rjhdk cgqr gh Variable gksrk gSA Applet ;k Application ij fn[kkbZ nsus okys fofHkUu izdkj ds Components fuEu fLFkfr;ksa ls izHkkfor gksrs gSa% 1 Applet Window dh Size ls 2 vU; Components o Containers dh Size ls 3 Use fd, tkus okys Layout Manager ls

Flow Layout Manager tkok esa ftrus Hkh Container Controls gksrs gSa] mu lHkh ds lkFk ,d Layout Manager Associated gksrk gSA Layout Manager Layout Class dk ,d Object gksrk gS] ftlesa LayoutManager Interface dks Implement fd;k x;k gksrk gSA fdlh Layout dks Set djus ds fy, gesa setLayout() Method dks Use djuk gksrk gSA ;fn ge fdlh Container ds lkFk fdlh Layout dks Set ugha djrs gSa] rks ml Container ds lkFk ,d Default Layout Manager Set gks tkrk gS] ftldk uke FlowLayout gksrk gSA ge tc Hkh fdlh Container Object dks Resize djrs gSa] Container ls Associated LayoutManager ml Container ds lHkh Objects dks Relatively Resize djds Container esa fQj ls Set dj nsrk gSA tkok esa Multiplatform ij Use fd, tkus okys GUI Applications ;k Applets cuk, tkrs gSaA tcfd fofHkUu izdkj ds Platforms ij GUI leku fn[kkbZ ugha nsrs gSaA

tkok esa Layout Manager s dk iz;ksx blhfy, fd;k x;k gS] rkfd ge tkok ds Programs dks fdlh Hkh Platform ij Execute djsa] os lHkh Platform ij leku fn[kkbZ nsaA tc ge fdlh Container ds fy, fdlh Layout dks Manually Set djuk pkgrs gSa] rks gesa fuEukuqlkj Statement Use djuk gksrk gS% void setLayout(LayoutManager layoutObj)

bl Statement esa layoutObj ml Layout Object dk Reference gS] ftls ge Container ds fy, Set djuk pkgrs gSaA ;fn ge fdlh Container ds fy, fdlh Layout dks Use djuk ugha pkgrs] cfYd ge Controls dks mudh Actual Position ij Place djuk pkgrs gSa] rks gesa layoutObj Argument esa null Specify djuk gksrk gSA ysfdu ;fn ge fdlh Container ds fy, Layout dks null dj nsrs gSa] rks Container esa Place gksus okys lHkh Components dh Size o Position dks gesa gh Specify djuk t:jh gks tkrk gS] vU;Fkk gesa Container esa dksbZ Hkh Component fn[kkbZ ugha nsrk gSA fofHkUu Components dh Size r; djus ds fy, gesa setBounds() Method dks Use djuk iMrk gS] lkFk gh fofHkUu Components dks Container ds fy, Visible Hkh cukuk iMrk gSA


Java in Hindi ge ftl fdlh Hkh Layout Manager dks Use djrs gSa] og Layout Manager ml Components ds uke dk Record ;k Track j[krk gS vkSj ge tSls gh fdlh Container esa fdlh Component dks Add djrs gSa] og Layout Manager Notify gks tkrk gSA tc Hkh ge ml Container dks Resize djrs gSa] Layout Manager minimumLayoutSize() o preferredLayoutSize() Method dks Use djds Container ds lHkh Components dh Size dks vuqikr esa de dj nsrk gSA tks Hkh Component fdlh Layout Manager }kjk Manage gks jgk gksrk gS ;kuh tks Hkh Component fdlh Container esa Add fd;k tkrk gS] ml Component esa getPreferredSize() o getMinimumSize() uke dk Method gksrk gSA ;s nksuksa Methods fdlh Component }kjk Display gksus okyh Preferred o Minimum Size dks Return djrs gSaA tgka rd lEHko gksrk gS] Layout Manager lHkh Objects dks vius fu;eksa ds vuqlkj Manage djrk gSA tkok esa fofHkUu izdkj ds Layout Manager gSa] ftudk iz;ksx djds ge gekjh t:jr dks iwjk dj ldrs gSaA lkFk gh ge gekjh t:jr ds vuqlkj u;k Layout Manager Hkh Define dj ldrs gSaA

FlowLayout Manager tkok esa dbZ rjg ds Layout Managers gSa] ftudk iz;ksx djds Applet ij Place gksus okys fofHkUu Controls dh Location o Size esa Required ifjorZu fd;k tk ldrk gSA FlowLayout Class Applet dk Default Layout Manager gksrk gS] ftldk iz;ksx Automatically vHkh rd ds lHkh Applet Programs ds Applets esa gqvk gSA FlowLayout esa fofHkUu Components mlh rjg ls Applet ij Place gksrs pys tkrs gSa] ftl rjg ls fdlh Page ij fofHkUu “kCn Print gksrs pys tkrs gSaA tSls gh Page dh Line iwjh gksrh gS] ckdh ds “kCn vxyh Line esa Print gksus yxrs gSaA Bhd blh rjg ls tSls gh Applet esa txg Hkj tkrh gS] fofHkUu Controls vxyh Line esa Place gksus yxrs gSaA Applet ds fofHkUu Components dks FlowLayout esa Setup djus ds fy, gesa FlowLayout Class dk ,d Object Create djds bls ,d Argument ds :i esa setLayout() Method esa Pass fd;k tkrk gSA ;kuh bl Layout dks ;fn ge Manually Set djuk pkgsa] rks gesa fuEukuqlkj Statement fy[kus gksrs gSa% FlowLayout myLayout = new FlowLayout(); setLayout(myLayout); FlowLayout Class fdlh Applet ds fy, ,d Default Layout Manager gksrk gSA Flow Layout Manager fofHkUu Controls dks Applet ij mlh Sequence esa ,d Horizontal Row esa Place djrk gS] ftl Sequence esa os init() Method esa add() Method dk iz;ksx djds Add fd, tkrs gSaA

tSls gh ;s Manager Applet ds Right Border rd igqaprk gS] ;s ckdh ds Controls dks vxys Horizontal Row esa Place djuk “kq: dj nsrk gSA ;s Layout viuh Default fLFkfr esa fofHkUu Controls dks Applet ds Center esa Place djrk gSA FlowLayout Class ds rhu Constructors gSa tks fd fuEukuqlkj gSa% public FlowLayout(); public FlowLayout(int align); public FlowLayout(int align, int hgap, int vgap);

// No-Argument Constructor // 1-Argument Constructor


Java in Hindi //3-Argument Constructor No-Argument Constructor ,d u;k FlowLayout Manager Object Create djrk gS vkSj Applet ij Place fd, tkus okys lHkh Controls dks Applet ds Center esa Place djrk gSA lkFk gh lHkh Controls vkil esa By-Default Vertically o Horizontally 5-5 Pixels nwj Place gksrs gSaA 1-Argument Constructor }kjk Create gksus okyk Layout Manager Object ml fn”kk ls Controls dks Applet ij Place djuk “kq: djrk gS] ftl fn”kk dk ge 1-Argumnet Constructor esa mYys[k dj nsrs gSaA tcfd bl Constructor dk iz;ksx djus ij Hkh fofHkUu Controls Default :i ls Horizontally o Vertically 5-5 Pixels nwj Place gksrs gSaA 3-Argument Constructor }kjk ge ,slk Layout Object Create dj ldrs gSa] ftls Set djds ge ;s r; dj ldrs gSa] fd Controls fdl fn”kk ls Form ij Place] gksaxs vkSj fofHkUu Controls ds chp Horizontally o Vertically fdruk Gap jgsxkA align bl Argument ds LFkku ij gesa fuEu esa ls fdlh ,d Constant dks Use djuk gksrk gS% FlowLayout.LEFT FlowLayout.RIGHT FlowLayout.CENTER -

tc Controls dks Left ls Place djuk gks tc Controls dks Right ls Place djuk gks tc Controls dks Center esa Place djuk gks

hgap, vgap bu Arguments ds LFkku ij ge mu Pixels dh la[;k dks Specify djrs gSa] ftrus Pixels dh nwjh gesa Horizontally o Vertically nks Controls ds chp j[kuh gksrh gSA mnkgj.k ds fy, ;fn gesa Applet ij fofHkUu Controls dks Left ls Place djuk gks lkFk gh lHkh Controls ds chp dh nwjh dks 10 Pixel Horizontally o 5 Pixels Vertically j[kuk gks] rks fuEu Applet esa ge ;s

dke fuEukuqlkj dj ldrs gS%a

Program // File Name: ButtonNTextBoxApplet.java import java.awt.*; import java.applet.*; public class ButtonNTextBoxApplet extends Applet{ TextField txtBox1 = new TextField(10), txtBox2 = new TextField(10); Button OKButton = new Button("OK"); FlowLayout organizeControls = new FlowLayout(FlowLayout.LEFT, 10, 5);

}

public void init(){ setLayout(organizeControls); add(txtBox1); add(txtBox2); add(OKButton); }

Output


Java in Hindi

FlowLayout Manager dk iz;ksx ge fdlh Specific Container tSls fd Panel Object ds fy, Hkh dj ldrs gSaA ;s dke ge setLayout() Method dk iz;ksx djds dj ldrs gSaA ;kuh ge fdlh Hkh Layout dks setLayout() Method dk iz;ksx djds fdlh Hkh Container ls Associate dj ldrs gSaA ;fn gesa fdlh Layout dks fdlh Panel Object ls Associate djuk gks] rks ge ;s dke fuEukuqlkj Statement }kjk dj ldrs gSa% Panel inputArea = new Panel(); FlowLayout inputLayout = new FlowLayout(); inputArea.setLayout(inputLayout);

bu Statements dk eryc ;s gS fd ge tks Hkh Controls add() Method dk iz;ksx djds Add djsaxs] os lHkh Controls FlowLayout Manager ds inputLayout Object ls Associate gks tk,axs vkSj bl FlowLayout Manager Object dks ge setLayout() Method dk iz;ksx djds Panel Object inputArea ls Associate dj nsaxsA ftlls inputLayout uke ds Object esa Associated lHkh Controls inputArea uke ds Panel Object ls Associate gks tk,axsA dsoy FlowLayout Manager dk iz;ksx djds ge fdlh Applet ij fLFkr fofHkUu Controls dks Bhd ls Organized ugha dj ldrs gSaA fofHkUu Controls dks Applet ij Bhd ls Organize djus ds fy, gesa de ls de ,d vkSj Layout Manager dh t:jr gksrh gSA bl Layout ds vykok Hkh tkok esa dqN vkSj mi;ksxh Layout Manager s gSaA

BorderLayout Manager ;s Layout Top-Level Windows ds fy, ,d Common Layout Implement djrk gSA bl Layout essa Window ds pkjksa rjQ pkj Fixed Width Components gksrs gSa] tcfd blds Center esa ,d cMk Area gksrk gSA Window ds pkjksa Sides dks North, South, East o West uke ls rFkk e/; Hkkx dks Center uke ls Identify fd;k tkrk gSA BorderLayout Manager esa Define fd, tkus okys Constructors fuEukuqlkj gS% BorderLayout() BorderLayout(int hori, int vert)

igyk Constructor ,d Default Border Layout Create djrk gS] tcfd nwljk Constructor Container ds Horizontal o Vertical Controls ds chp NksMs tkus okys Space dks Define djus dh lqfo/kk iznku djrk gSA bl Layout esa ge fuEu Constant ekuksa dk iz;ksx djds Container dh Regions dks Specify dj ldrs gSa% BorderLayout.CENTER BorderLayout.EAST

BorderLayout.SOUTH BorderLayout.WEST


Java in Hindi BorderLayout.NORTH

tc ge Components dks Container esa Add djrs gSa] rc gesa bu Components dks Container esa Add djus ds fy, fuEukuqlkj Syntax dk iz;ksx djuk gksrk gS% void add(Component compObj, Object regions)

;gka compObj og Object gS ftls Container esa Add fd;k tkuk gS vkSj regions og LFkku Specify djrk gS] tgka Component Add fd;k tkus okyk gSA

GridLayout Manager GridLayout Class fdlh Container ds lHkh Components dks ,d Specific Rows o Columns esa Organize djrk gSA ;kuh bl Layout dk lcls ljy fu;e ;s gS fd Applet ;k Container ds Display gksus okys Area dks Programmer viuh vko”;drkuqlkj Rows o Columns dh la[;k lqfuf”pr djds Rows o Columns esa ckaV nsrk gSA User ftl la[;k dks lqfuf”pr djrk gS] og la[;k Display gksus okys dqy Rows o Columns dh la[;k gksrh gSA ;kuh ;fn User Grid dh la[;k (2, 3) r; djrk gS] rks Display Area dqy ( 2 * 3 ) 6 Hkkxksa (Cells) esa foHkkftr gks tkrk gS] vkSj lHkh Cells ,dne cjkcj gksrs gSaA

bl Layout esa Controls Display Area ds First Cell ls Place gksuk “kq: gksrs gSa vkSj tc Display Area esa vkSj Controls ds fy, Space ugha cprk gS] rc Controls vxyh Line ds Left Most Cell ls Place gksuk “kq: gksrs gSaA bl Layout esa gesa fuEu Constructors izkIr gksrs gSa% GridLayout() GridLayout(int numRows, int numColumns) GridLayout(int numRows, int numColumns, int hori, int vert)

rhljk Constructor gesa Display gksus okys fofHkUu Components ds chp NksMs tkus okys Vertical o Horizontal Space dks Specify djus dh lqfo/kk iznku djrk gS] fQj pkgs numRows o numColumns dk eku 0 gh D;ksa uk gksA numRows dk eku 0 Specify djus dk eryc gksrk gS fd ge Unlimited-Length Rows Specify dj jgs gSa] tcfd numColumns dk eku 0 Specify djus dk eryc gksrk gS] ge Unlimited-Length Column Define dj jgs gSaA Menu Bars and Menus ,d Top-Level Window ds lkFk ,d Menu Associate fd;k tk ldrk gSA ,d Menu Bar Top-Level Menu Choices dh ,d List Display djrk gSA gj Choice ,d Drop-Down Menu ls Associated gksrk gSA Menu Bar ds Concept dks tkok esa MenuBar, Menu o MenuItem Classes dk iz;ksx djds Implement fd;k tkrk gSA lkekU;r;k Menu Bar esa ,d ;k ,d ls vf/kd Menu Objects gksrs gSaA gekjs Menu Object esa ,d MenuItem Object gksrk gSa vkSj gj MenuItem Object dqN Options Display djrk gS] ftUgsa User Select dj ldrk gSA


Java in Hindi pwafd Menu Class MenuItem Class dh Sub Class gS] blfy, Nested Sub Menus dh Hierarchy Create dh tk ldrh gSA lkFk gh ge fdlh Menu esa Checkable Menu Items Hkh Create dj ldrs gSaA bl izdkj ds Checkable Menu Items dks CheckboxMenuItem dgrs gSa vkSj tc bUgsa Select fd;k tkrk gS] rc buds lkFk ,d Check Mark Associated gks tkrk gSA Menu Bar Create djus ds fy, gesa lcls igys MenuBar Class dk ,d Object Create djuk gksrk gSA bl Class esa dsoy ,d Default Constructor gksrk gSA fQj gesa Menu Class dk ,d Object Create djuk gksrk gS] tks fd mu Menus dks Define djrk gS] tks Menu Bar ij Display gksrs gSaA Menu Class esa fuEu Constructors gksrs gSa% Menu() Menu(String optionName) Menu(String optionName, boolean removable)

;gka optionName Menu Selection ds uke dks Specify djrk gSA ;fn removable Argument esa true Specified gks] rks Pop-up Menu dks Menu Bar ls Remove fd;k tk ldrk gSA igyk Constructor ,d Empty menu Bar Create djrk gSA gj Individual Menu Item MenuItem Class dk Object gksrk gSA bl Class esa fuEu Constructors gksrs gSa% MenuItem() MenuItem (String itemName) MenuItem (String itemName, MenuShortcut keyAccel)

bu Constructors esa itemName og uke gS tks Menu esa Option ds :i esa fn[kkbZ nsrk gS vkSj keyAccel Menu ds ml Option dks Shortcut gksrk gSA ge fdlh Menu Item dks setEnabled() Method dk iz;ksx djds Enable ;k Disable dj ldrs gSaA ;s Method fuEukuqlkj gksrk gS% void setEnabled(boolean enabledFlag)

;fn enabledFlag Argument esa true gks rks og Menu Item Enabled jgrk gS vkSj ;fn blesa false gks rks og Menu Item Disabled gks tkrk gSA dksbZ Menu Item Enabled gS ;k Disabled bl ckr dh tkudkjh izkIr djus ds fy, ge isEnabled() Method dks Use dj ldrs gSa] ftldk Syntax fuEukuqlkj gksrk gS% boolean isEnabled()

;fn Check fd;k tkus okyk Menu Item Enabled gks rks ;s Method true Return djrk gS] vU;Fkk false Return djrk gSA fdlh Menu Item ds Label dks Change djus ds fy, ge setLabel() Method dks Use dj ldrs gSa vkSj fdlh Menu Item ds Label dks izkIr djus ds fy, ge getLabel() Method dks Use dj ldrs gSaA buds Syntax fuEukuqlkj gSa% void setLabel(String newName) String getLabel() Checkable Menu Item Create djus ds fy, gesa MenuItem dh Subclass CheckboxMenuItem dks Use djuk gksrk gSA blds Constructors fuEukuqlkj gSa%


Java in Hindi CheckboxMenuItem() CheckboxMenuItem(String itemName) CheckboxMenuItem(String itemName, boolean on)

;gka itemName og uke gS ftls Menu esa Checkable Form esa Display djuk gksrk gSA ;fn gesa Menu esa fdlh Item dks Checked j[kuk gksrk gS] rks gesa on Argument esa true Pass djuk gksrk gSA igys nks Constructors ,d Unchecked MenuItem Create djrs gSaA fdlh Checkable Menu Item dh Status izkIr djus ds fy, gesa getState() Method dks Use djuk gksrk gSA tcfd fdlh Menu Item dh State dks Set djus ds fy, ge setState() Method dks Use dj ldrs gSaA budk Syntax fuEukuqlkj gS% boolean getState() void setState(boolean checked)

tc dksbZ Menu Item Checked gksrk gS] rc getState() Method true Return djrk gS] tcfd Unchecked gksus ij false Return djrk gSA blh rjg ls tc gesa fdlh Unchecked Menu Item dks Check djuk gks ;k Checked Menu Item dks Unchecked djuk gks] rc ge setState() Method dks Use djrs gSaA Menu Item Create djus ds ckn gesa bu Menu Items dks Menu Object esa add() Method }kjk Add djuk gksrk gSA blds fy, ge add() Method dks fuEu rjhds ls Use djrs gSa% MenuItem add(MenuItem item)

bl Statement esa item og Item gS] ftls menu esa Add djuk gSA ge ftl Øe esa add() Method dks Call djrs gSa] Menu esa mlh Øe esa Menu Items Add gksrs gSaA tc ,d ckj ge fofHkUu Menu Items dks Add dj ysrs gSa] mlds ckn ge ml MenuItem Object dks Menu Bar esa Add dj ldrs gSaA blds fy, Hkh gesa add() Method dks Call djuk gksrk gS] tks fd

ge fuEukuqlkj djrs gSa%

Menu add(Menu menu) Menus gesa”kk rHkh Event Generate djrs gSa] tc User fdlh MenuItem ;k CheckboxMenuItem ds fdlh Option dks Select djrk gSA ge tc Hkh fdlh Menu Item dks Select djrs gSa] ,d ActionEvent Object Generate gksrk gS vkSj ge tc Hkh fdlh CheckboxMenuItem dks Select djrs gSa] ,d ItemEvent Object Generate gksrk gSA blfy, gesa ActionListener o ItemListener Interface dks bu Generate gksus okys Events dks Listen djus ds fy, Implement djuk gksrk gSA ItemEvent Object dk getItem() Method ml Item dk Reference Return djrk gS] ftlus Event Object dks Generate fd;k gksrk gSA bl Method dk Syntax fuEukuqlkj gksrk gS% Object getItem()

pfy,] vc Menu Creation dh bl iwjh izfØ;k dks Practically le>rs gSaA tkok esa Menu Bar Create djus ds fy, lcls igys gesa MenuBar Class dk ,d Object Create djuk gksrk gSA ;s dke ge fuEukuqlkj Statement }kjk djrs gSa% MenuBar myFirstMenu = new MenuBar(); 538 Any Question or Suggestion, Just Discuss Here...

Java in Hindi MenuBar Class dk Object Create djus ds ckn gesa bl Menu Bar dks fdlh Frame Window ls Attach djuk gksrk gSA fdlh Frame Window ls Menu Bar Object dks Connect djus ds fy, lcls igys gesa Frame Class dk ,d Object Create djds Frame Create djuk gksrk gSA ;s dke ge fuEukuqlkj djrs gSa% Frame myFrame = new Frame(“Frame with Menu”); Frame Create djus ds ckn Create fd, x, Menu Bar Object dks bl Frame ls Attach djus ds fy, gesa setMenuBar() Method dks Use djuk gksrk gSA bl Method dk iz;ksx djds ge Create gksus okys Menu Bar dks Frame Window ls Attach dj ldrs gSaA bl method dks gesa fuEukuqlkj Use djuk gksrk gS% myFrame.setMenuBar(myFirstMenu);

pwafd] vHkh geus Frame ls tks Menu Connect fd;k gS] og Menu Bar iwjh rjg ls Empty gS] D;ksafd mlesa vHkh rd dksbZ Hkh Menu ugha gSA bl Menu Bar esa u;k Menu Attach djus ds fy, vc gesa Menu Class dk Object Create djuk gksrk gSA gesa Menu Bar esa ftrus Menu Attach djus gksrs gSa] mrus Menu Object Create djus gksrs gSaA Menu Class dk Object djus ds fy, gesa fuEukuqlkj Menu Objects Create djus gksrs gSa% Menu fileMenu = new Menu(“File”); Menu editMenu = new Menu(“Edit”); Menu optionMenu = new Menu(“Options”); Menu Class ds Constructor esa gesa Menu Bar ij fn[kkbZ nsus okys uke dks Specify djuk gksrk gSA bl Constructor esa ge tks String Pass djrs gSa] og String Caption ds :i esa Menu Bar ij fn[kkbZ nsrk gSA Menus dks Create djus ds ckn gesa bu Menus dks Menu Bar Object ls Attach djuk gksrk gSA Menus dks MenuBar Object ls Attach djus ds fy, gesa add() Method dks Use djuk gksrk gSA ;s dke ge fuEukuqlkj dj ldrs gSa% myFirstMenu.add(fileMenu); myFirstMenu.add(editMenu); myFirstMenu.add(optionMenu);

fofHkUu Menus dks Menu Bar ls Connect djus ds ckn gesa Menus esa fn[kkbZ nsus okys Items dks Create djuk gksrk gSA Menu Items dks Create djus ds fy, gesa MenuItem Class dks Use djuk gksrk gSA MenuItem Object Create djus ds fy, gesa fuEukuqlkj Statements Use djuk gksrk gS% MenuItem mOpen = new MenuItem(“Open”) MenuItem mClose = new MenuItem(“Close”) MenuItem mUndo = new MenuItem(“Undo”) MenuItem mRedo = new MenuItem(“Redo”) MenuItem mOption1 = new MenuItem(“Option1”) MenuItem mOption2 = new MenuItem(“Option2”)


Java in Hindi ;fn ge fdlh Checkbox Menu Item dks Create djuk pkgsa] rks gesa CheckboxMenuItem Class dk Object Create djuk gksrk gSA ;s Object ge fuEukuqlkj Create dj ldrs gSa% CheckboxMenuItem mOption3= new CheckboxMenuItem(“mOption3”)

dbZ Menus ds fofHkUu Items ds chp gesa ,d Line Use djuh gksrh gSA bl Line dks Separator dgrs gSaA ge bl Separator dks Hkh ,d MenuItem Object dh rjg Create djds Menu esa Add dj ldrs gSaA Separator Create djus ds fy, gesa fuEukuqlkj Statement Use djuk gksrk gS% MenuItem mSeparator = new MenuItem(“-”)

//Separator

fofHkUu izdkj ds Menu Items Create djus ds ckn bu Items dks muls lEcaf/kr Menu ls Attach djuk gksrk gSA Menu ls fofHkUu Menu Items dks Attach djus ds fy, gesa fuEukuqlkj add() Method dks Call djuk gksrk gS% fileMenu.add(mOpen) fileMenu.add(mClose) editMenu.add(mUndo) editMenu.add(mRedo) optionMenu.add(mOption1) optionMenu.add(mOption2) optionMenu.add(mSeparator) optionMenu.add(mOption3)

fdlh Menu esa ;fn gesa Separator Add djuk gks] rks ge setSeparator() Method dk iz;ksx Hkh dj ldrs gSaA ;kuh ekuyks fd gesa gekjs Option Menu esa ,d Separator Add djuk gS] rks ;s dke ge fuEukuqlkj Hkh dj ldrs gSa% optionMenu.add(mOption1) optionMenu.add(mOption2) optionMenu.addSeparator() optionMenu.add(mOption3)

vc ;fn ge gekjs Program dks Compile djds Run djrs gSa] rks gesa gekjs Frame Window ds lkFk ,d Menu Bar Hkh fn[kkbZ nsrk gSA bl iwjh izfØ;k dks ge fuEukuqlkj ,d Program }kjk le> ldrs gSaA Program // File Name : ManuDemoApp.java import java.awt.*; public class ManuDemoApp { public static void main(String arts[]) { // Create a frame and a MenuBar


Java in Hindi Frame myFrame = new Frame("My Frame with Menu"); MenuBar myMenubar = new MenuBar(); // Add the MenuBar to the frame myFrame.setMenuBar(myMenubar); // Create the File and Edit Menus and Attach it with the MenuBar Menu mFile = new Menu("File"); Menu mEdit = new Menu("Edit"); myMenubar.add(mFile); myMenubar.add(mEdit); // Add New and Close options to File Menu and // Add Copy and Paste to the Edit Menu MenuItem mNew = new MenuItem("New"); MenuItem mClose = new MenuItem("Close"); mFile.add(mNew); mFile.add(mClose); MenuItem mCopy = new MenuItem("Copy"); MenuItem mPaste = new MenuItem("Paste"); mEdit.add(mCopy); mEdit.add(mPaste); // Make Close disabled mClose.setEnabled(false); // Create Print checkbox, followed by separator CheckboxMenuItem mPrint = new CheckboxMenuItem("Print"); mFile.add(mPrint); mFile.addSeparator(); // Create Font submenu Menu mFont = new Menu("Font"); mFile.add(mFont); mFont.add("Arial"); mFont.add("Times New Romans"); // Resize the frame myFrame.setSize(300, 200);

}

}

// Display the Frame on the screen myFrame.setVisible(true);

Output


Java in Hindi

dbZ ckj ge gekjs Program esa Pop-up Menu Add djuk pkgrs gSaA Pop-up Menu ,d ,slk Menu gksrk gS] tks Frame Window ;k Applet esa Mouse ds Right Button dks Click djus ij Display gksrk gSA tc gesa gekjs Program esa Popup Menu Attach djuk gksrk gS] rc gesa fuEu Øe esa fofHkUu dke djus gksrs gSa% 1 lcls igys PopupMenu Class dk ,d Object Create fd;k tkrk gSA ;s dke ge fuEukuqlkj dj ldrs gSa% PopupMenu myPopup = new PopupMenu();

2 PopupMenu Class dk Object Create djus ds ckn gesa ,d Menu Create djuk gksrk gS] ftls ge Popup Menu Object esa Add djuk pkgrs gSaA ;s dke djus ds fy, gesa Menu Class dk ,d Object Create djuk gksxk vkSj ml Object dks PopupMenu Object ls Add djuk gksxkA ;s dke ge fuEukuqlkj dj ldrs gSa% Menu myPopupMenu = new Menu(“Popup”); myPopup.add(myPopupMenu);

3 PopupMenu ls Menu dks Add djus ds ckn gesa ml Menu esa Display gksus okys Menu Items Create djus gksrs gSa vkSj mu Menu Items dks Menu Object esa Add djuk gksrk gSA ;s dke ge fuEukuqlkj dj ldrs gSa% MenuItem mRefresh = new MenuItem(“Refresh”); myPopupMenu.add(mRefresh);

Dialog Boxes dbZ ckj gesa Related Controls ds ,d lewg dks Hold djus ds fy, Dialog Box dh t:jr gksrh gSA lkekU;r;k Dialog Boxes dk iz;ksx User ls Input izkIr djus ds fy, fd;k tkrk gSA mnkgj.k ds fy, “Open” Dialog Box fdlh File dks Open djus ds fy, Use gksrk gS tcfd “Save As” Dialog Box fdlh File dks Save djus ds fy, Use fd;k tkrk gSA Dialog Box ,d izdkj dk Frame Window gh gksrk gSA vUrj dsoy bruk gS fd Dialog Box gesa”kk fdlh nwljs Parent Window dk Child Window gksrk gSA 542 Any Question or Suggestion, Just Discuss Here...

Java in Hindi lkFk gh ge fdlh Dialog Box ds lkFk Menu Bar dks Attach ugha dj ldrs gSaA buds vykok ftruh Hkh ifjfLFkfr;ka gksrh gSa] muesa Dialog Box Window mlh rjg ls dke djrk gS] ftl rjg ls ,d Frame Window djrk gSA ;kuh ge fdlh Dialog Box esa Hkh mlh rjg ls fofHkUu GUI Controls Add dj ldrs gSa] ftl rjg ls fdlh Frame Window esa djrs gSaA Dialog Boxes Modal ;k Modeless gks ldrs gSaA ,d ,slk Dialog Box tks tc rd Visible jgrk gS] rc rd ge Parent Window dks fdlh izdkj ls Access ugha dj ldrs gSa] Modal Dialog Box dgykrk gSA ;kuh tc rd ,d Modal Dialog Box Active jgrk gS] rc rd ftrus Hkh Input fd, tkrs gSa] mu lHkh Inputs dks Dialog Box gh Receive djrk gSA

bldk eryc ;s gS fd ge tc rd fdlh Modal Dialog Box dks Close ugha dj nsrs gSa] rc rd ge mlds Parent Window ls fdlh izdkj dk dke ugha dj ldrs gSaA tcfd ;fn Dialog Box Modeless gks] rks ,slk ugha gksrk gSA ;kuh ,sls Dialog Box ds Open gksus ds fLFkfr esa Hkh ge Application ds vU; fgLlksa dks Access djus esa l{ke gksrs gSaA lkekU;r;k Dialog Box Create djus ds fy, gesa Dialog Class dks Use djuk gksrk gSA bl Class esa fuEukuqlkj nks Constructors gksrs gSa% Dialog(Frame parentWindow, boolean mode) Dialog(Frame parentWindow, String title, boolean mode)

bl Constructor esa parentWindow og Frame Window gksrk gS] ftlesa Dialog Box Child Window dh rjg Add fd;k tkrk gSA ;fn mode esa true gks] rks Create gksus okyk Dialog Box Modal Dialog Box gksrk gS] vU;Fkk ;s ,d Modeless Dialog Box Create djrk gSA title Argument esa ge tks String Pass djrs gSa] og String Dialog Box ds Title ds :i esa fn[kkbZ nsrh gSA lkekU;r;k ge Dialog Class dks Extend djds mldh Sub Class Create djrs gSa vkSj mlesa Application }kjk Required Functionalities dks Add dj ysrs gSaA Program // File Name : DialogBoxWithMenuBar.java import java.awt.*; import java.awt.event.*; import java.applet.*; // Create Subclass of Dialog. class SubDialog extends Dialog implements ActionListener { SubDialog(Frame parent, String title){ super(parent, title, false); setLayout(new FlowLayout()); setSize(200, 150); add(new Label("Press this button")); Button btnCancel; add(btnCancel = new Button("Cancel"));


Java in Hindi }

btnCancel.addActionListener(this);

public void actionPerformed(ActionEvent actnEvnt) { dispose(); } public void paint(Graphics g) { g.drawString("This is in the dialog box", 10, 60); }

} //------------------------------------------------------------------// Create a subclass of Frame class MenuFrame extends Frame { String message = ""; CheckboxMenuItem debug, test; MenuFrame(String title) { super(title); // Create menubar and add it to frame MenuBar mBar = new MenuBar(); setMenuBar(mBar); // Create Menu Items Menu file = new Menu("File"); MenuItem mNew, mClose; file.add(mNew = new MenuItem("New")); file.add(mClose = new MenuItem("Close")); mBar.add(file); // These are checkable items of edit menu Menu edit = new Menu("Edit");

debug = new CheckboxMenuItem("Debug"); edit.add(debug); test = new CheckboxMenuItem("Testing"); edit.add(test); mBar.add(edit); // Create an Listener Object MyMenuHandler handler = new MyMenuHandler(this);


Java in Hindi // Register it to receive Menu events mNew.addActionListener(handler); mClose.addActionListener(handler); debug.addItemListener(handler); test.addItemListener(handler); // Create an object to handle window events MyWindowAdapter adapter = new MyWindowAdapter(this);

}

// Register it to receive Window events addWindowListener(adapter);

public void paint(Graphics g) { g.drawString(message, 10, 150); if(debug.getState()) g.drawString("Debug is on ", 10, 220); else g.drawString("Debug is off ", 10, 220);

}

if(test.getState()) g.drawString("Test is on ", 10, 240); else g.drawString("Test is ff ", 10, 240);

} //-------------------------------------------------------------------------class MyWindowAdapter extends WindowAdapter { MenuFrame myMenuFrame; public MyWindowAdapter(MenuFrame mnuFrame) { this.myMenuFrame = mnuFrame; } public void windowClosing(WindowEvent wndEvnt) { myMenuFrame.dispose(); }

} //--------------------------------------------------------------------------


Java in Hindi class MyMenuHandler implements ActionListener, ItemListener { MenuFrame myMenuFrame; public MyMenuHandler(MenuFrame myMenuFrame) { this.myMenuFrame = myMenuFrame; } // Handle action events public void actionPerformed(ActionEvent actnEvnt) { String message = "You have selected "; String argument = (String)actnEvnt.getActionCommand(); // Activate a Dialog Box when File->New Option is selected if(argument.equals("New")) { message = message + "New..."; SubDialog dialogBox = new SubDialog(myMenuFrame, "NewDialogBox"); dialogBox.setVisible(true); } // Other Menu Options else if(argument.equals("Close")) message += "Close"; else if(argument.equals("Debug")) message += "Debug";

}

else if(argument.equals("Testing")) message += "Testing...";

public void itemStateChanged(ItemEvent itmEvnt) { myMenuFrame.repaint(); }

} //-------------------------------------------------------------------------// Create Frame Window public class DialogBoxWithMenuBar extends Applet { Frame myFrame; public void init() {


Java in Hindi myFrame = new MenuFrame("Accessible Menu"); int width = Integer.parseInt(getParameter("width")); int height = Integer.parseInt(getParameter("height")); setSize(width, height);

}

myFrame.setSize(width, height); myFrame.setVisible(true);

public void start() { myFrame.setVisible(true); }

}

public void stop() { myFrame.setVisible(false); }

Output

FileDialog Class tkok gesa ,d Built-In Dialog Box Class Provide djrk gS] tks gesa User }kjk Specify dh tkus okyh File dks Open djus dh lqfo/kk iznku djrk gSA bls File Dialog Box dgrs gSaA FileDialog Box Create djus ds fy, gesa FileDialog Class dk ,d Object Create djuk gksrk gSA ,slk djus ij ,d FileDialog Box Display gksus yxrk gSA lkekU;r;k ;s ,d Standard FileDialog Box gksrk gS] tks gesa Operating System }kjk izkIr gksrk gSA FileDialog Class esa fuEukuqlkj rhu Constructors gksrs gSa% FileDialog(Frame parent, String boxName) FileDialog(Frame parent, String boxName, int how) 547 Any Question or Suggestion, Just Discuss Here...

Java in Hindi FileDialog(Frame parent)

;gka parent Argument esa gesa FileDialog Box ds Parent Window dk uke nsuk gksrk gS] tcfd boxName Argument esa FileDialog Box ds Title Bar ij fn[kkbZ nsus okys uke dks Specify djuk gksrk gSA ;fn bl Argument dks NksM fn;k tk,] rks Display gksus okys Dialog Box ij dksbZ Title ugha gksrk gSA how Argument esa ;fn ge FileDialog.LOAD Specify djrs gSa] rks File Open djus okyk “Open” Dialog Box Display gksrk gS] tcfd ;fn bl Argument esa ge FileDialog.SAVE Constant Specify djsa] rks File dks Save djus ds fy, “Save As” Dialog Box Display gksus

yxrk gSA

rhljk Constructor ,d ,slk FileDialog Box Open djrk gS] ftlls ge fdlh File dks Reading Mode esa Open djus ds fy, Select dj ldrs gSaA FileDialog gesa nks Methods Provide djrk gS] ftudk iz;ksx djds ge User }kjk Select fd, x, File ds uke o Path dks izkIr dj ldrs gSaA ;s Methods fuEukuqlkj gSa% String getDirectory(); String getFile()

;s Methods File o Directory dk uke Return djrs gSaA bls le>us ds fy, ge fuEukuqlkj Program fy[k ldrs gSa% Program // File Name : FileDialogApp.java import java.awt.*; import java.awt.event.*; // Create a subclass of Frame class MyFrame extends Frame { MyFrame(String title) { super(title); // Create an Listener Object MyWindowAdapter adapter = new MyWindowAdapter(this); // Register it with Listener to receive events addWindowListener(adapter);

} } //-------------------------------------------------------------------------class MyWindowAdapter extends WindowAdapter { MyFrame myFrame; public MyWindowAdapter(MyFrame mnuFrame){ 548 Any Question or Suggestion, Just Discuss Here...

Java in Hindi }

this.myFrame = mnuFrame;

public void windowClosing(WindowEvent wndEvnt){ myFrame.dispose(); }

} //-------------------------------------------------------------------------// Create Frame window class FileDialogApp { public static void main(String a[]) { Frame f = new MyFrame(“File Dialog Demo”); f.setVisible(true); f.setSize(200,150);

}

}

FileDialog fd = new FileDialog(f, “File Dialog”); fd.setVisible(true);

bl Program ds Memory esa Load gksrs gh ,d Frame Window Display gksrk gS vkSj Screen ij Open Dialog Box fn[kkbZ nsus yxrk gSA

Explicit Event Handling ;s Events dks Handle djus dk ,d pkSFkk o vfUre Alternate rjhdk gSA bl rjhds esa fdlh Component dks ,d Sub Class esa Extend fd;k tkrk gS vkSj fQj ml Method dks Override fd;k tkrk gS] tks Events dks Receive o Dispatch djrk gSA mnkgj.k ds fy, ge Button Class dks Derive dj ldrs gSa vkSj fQj mlds processActionEvent() Method dks Override dj ldrs gSaA processActionEvent() Method dk Default dke ;s gS fd og Event dks Event Listener esa Dispatch dj nsrk gSA lkekU;r;k bl rduhd dks Use ugha fd;k tkrk gS] D;ksafd blesa dqN dfe;ka gSaA bl rduhd dks tkok 1.0 Version esa Use fd;k x;k FkkA tc ge bl rduhd dks Use djuk pkgrs gSa ;kuh tc ge AWT Package dh fdlh Class dks Extend djuk pkgrs gSa] rc gesa Component Class ds enableEvents() Method dks Use djuk t:jh gksrk gSA bl Method dk Syntax fuEukuqlkj gksrk gS% protected final void enableEvents(long eventMask)

bl Method esa eventMask ,d Bit Mask gS] tks Current Component esa vkus okys Events dks Define djrk gSA AWTEvent Class esa bu Masks dks cukus ds fy, dqN Integer Constants dks Define fd;k x;k gSA muesa ls dqN Masks fuEukuqlkj gSa%


Java in Hindi ACTION_EVENT_MASK ADJUSTMENT_EVENT_MASK COMPONENT_EVENT_MASK CONTAINER_EVENT_MASK FOCUS_EVENT_MASK INPUT_METHOD_EVENT_MASK ITEM_EVENT_MASK

KEY_EVENT_MASK MOUSE_EVENT_MASK MOUSE_MOTION_EVENT_MASK MOUSE_WHEEL_EVENT_MASK TEXT_EVENT_MASK WINDOW_EVENT_MASK

blds vykok ge ftl Class dks Extend djrs gSa] gesa ml Class ds ,d Appropriate Method dks Hkh Override djuk t:jh gksrk gS] rkfd Event dks Process fd;k tk ldsA fofHkUu Components ds fy, Override fd, tkus okys Event Handling Methods fuEukuqlkj gSa% Class Button Checkbox CheckboxMenuItem Choice Component

List MenuItem Scrollbar TextComponent

Processing Method processActionEvent() processItemEvent() processItemEvent() processItemEvent() processComponentEvent(), processFocusEvent(), processKeyEvent(), processMouseEvent(), processMouseMotionEvent(), processMouseWheelEvent() processActionEvent(), processItemEvent() processActionEvent() processAdjustmentEvent() processTextEvent()

Extending Buttons bl Event Handling rduhd dks Button ds lkFk Use djus dh izfØ;k dks ge ,d mnkgj.k }kjk le>us dh dksf”k”k dj jgs gSaA vxys mnkgj.k esa geus ,d Applet Create fd;k gS] ftl ij ,d Button Object Create fd;k x;k gSA tc ge bl Button dks Click djrs gSa] rks Applet ds Status Bar esa “Action Event” String Display gksrk gSA lkFk gh Button dks dqy fdruh ckj Press fd;k x;k gS] mldh la[;k Hkh Status Bar esa Display gksrh gSA Program // File Name : ExtendingButtonApplet.java import java.awt.*; import java.awt.event.*; import java.applet.*; public class ExtendingButtonApplet extends Applet {


Java in Hindi MyButton btnPress; static int i = 0; public void init() { btnPress = new MyButton("Press Me"); add(btnPress); } // Extended Button Class class MyButton extends Button { public MyButton(String label) { super(label); enableEvents(AWTEvent.ACTION_EVENT_MASK); }

}

}

protected void processActionEvent(ActionEvent actnEvtn) { showStatus("Action Event : " + i++); super.processActionEvent(actnEvtn); }

Output

bl Program esa geus MyButton Class dks ,d Inner Class ds :i esa Applet esa Define fd;k gSA bl Class dks Button Class ls Derive fd;k x;k gSA MyButton Class esa Button ij Label Display djus ds fy, geus super() Method dks Use fd;k gSA bl Method dh otg ge Button ij tks Label nsuk pkgrs gSa] og Label MyButton Sub Class ds Constructor }kjk Button Super Class esa Pass fd;k tkrk gSA fQj MyButton Class ds Object }kjk Generate gksus okys Events dks Handle fd;k tk lds] blfy, bl Class ds Constructor esa enableEvents() Method dks Use fd;k gS vkSj Argument ds :i esa ;s Hkh crk;k gS fd MyButton Class ds Object }kjk Generate gksus okys fdl rjg ds Events dks ;s Inner Class Handle dj ldsxkA ;fn ge enableEvents() Method esa Argument ds :i esa MyButton Class }kjk Generate gksus okys Events dh tkudkjh uk nsa ;k bl Method dks bl rjg ls Call uk djsa]


Java in Hindi rks gekjk Button fdlh izdkj ds Event dks Response ugha djsxkA tc ge MyButton Class ds fdlh Button ij Click djrs gSa] rc ,d ActionEvent Object Generate gksrk gS vkSj tc dksbZ ActionEvent Object Generate gksrk gS] processActionEvent() Method Execute gks tkrk gSA pwafd MyButton Class Applet Class dh ,d Inner Class gS] blfy, ;s Class Applet Class ds fdlh Hkh Member dks Directly Access djus esa l{ke gSA bl rjg ls ge ,d Button Class dks Extends djds Event Handling ds fy, Use dj ldrs gSaA blh rjg ls ge vU; Classes dks Extend djds mUgsa Event Handling ds lkFk Use dj ldrs gSaA

Extending Checkbox bl Program esa geus Checkbox Class dks Bhd mlh rjg ls Use Event Handling ds fy, Use fd;k gS] ftl rjg ls geus Button Class dks Use fd;k gSA vUrj dsoy bruk gS fd bl Program esa Checkbox dks Click djus ij ItemEvent Generate gksrk gS] ftls Handle djus ds fy, processItemEvent() Method dks Override djuk gksrk gSA Program // File Name : ExtendingCheckboxApplet.java import java.awt.*; import java.awt.event.*; import java.applet.*; public class ExtendingCheckboxApplet extends Applet{ MyCheckbox check1, check2; static int i = 0; public void init(){ check1 = new MyCheckbox("Item1"); add(check1); check2 = new MyCheckbox("Item2"); add(check2); } // Extended Button Class class MyCheckbox extends Checkbox{ public MyCheckbox(String label) { super(label); enableEvents(AWTEvent.ITEM_EVENT_MASK); }

}

}

protected void processItemEvent(ItemEvent itmEvnt) { showStatus("Checkbox name/state: " + getLabel() +"/"+ getState()); super.processItemEvent(itmEvnt); }


Java in Hindi Output

bl Applet esa ge tc Hkh fdlh Check Box dks Click djrs gSa] rc ,d ItemEvent Generate gksrk gS] ftlds Response esa processItemEvent() Method Execute gks tkrk gS] vkSj Status Bar ij Check Box ls lEcaf/kr ,d Message Display gksus yxrk gSA blh rjg ls ge fofHkUu izdkj ds vU; Controls dks Hkh Extend djds Event Handling ds fy, Use dj ldrs gSaA dbZ ckj dbZ Controls ,d ls T;knk mnkgj.k ds fy, ,d List Control ds ItemEvent Generate gksrk gS] tcfd ActionEvent Object Generate gksrk

izdkj ds Events Generate djus esa l{ke gksrs gSaA fdlh Option dks tc Select fd;k tkrk gS] rc ,d List ds fdlh Option dks Double Click djus ij ,d gSA

bl fLFkfr esa ;fn ge List Control dks Extend djsa] rks gesa bu nksuksa izdkj ds Events dks Handle djuk t:jh gksrk gSA List dh Extending Process o Event Handling Process dks

fuEu mnkgj.k }kjk le>k tk ldrk gS%

Program // File Name : ExtendingListApplet.java import java.awt.*; import java.awt.event.*; import java.applet.*; public class ExtendingListApplet extends Applet{ MyList list; public void init(){ list = new MyList(); list.add("Red"); list.add("Green"); list.add("Blue"); }

add(list);

// Extended Button Class class MyList extends List{ public MyList(){ enableEvents(AWTEvent.ACTION_EVENT_MASK |


Java in Hindi }

AWTEvent.ITEM_EVENT_MASK );

protected void processItemEvent(ItemEvent itmEvnt) { showStatus("Item Event : " + getSelectedItem()); super.processItemEvent(itmEvnt); }

}

}

protected void processActionEvent(ActionEvent actnEvnt) { showStatus("Action Event : " + actnEvnt.getActionCommand()); super.processActionEvent(actnEvnt); }

Output

bl mnkgj.k esa ge ns[k ldrs gSa fd tc dksbZ Control ,d ls vf/kd izdkj ds Events Generate djus esa l{ke gksrk gS] rc gesa mu lHkh izdkj ds Events ds Mask dks enableEvents() Method esa Logical OR Operator }kjk Specify djuk gksrk gSA

Fonts Handling In Java tkok gesa Program ds Run Time esa Dynamically fdlh Hkh Font dks Select djus dk ,d cgqr gh Flexible rjhdk iznku djrk gSA ;kuh tkok esa ge Program ds Run Time esa Hkh fdlh Hkh Font dks Select djds vius Data dks fofHkUu Fonts esa Display dj ldrs gSaA AWT fofHkUu izdkj ds Fonts dks Support djrk gSA tkok esa gj Font fdlh Font Family dk lnL; gksrk gS] ftldk ,d Logical uke gksrk gS vkSj ,d Font Face uke gksrk gSA mnkgj.k ds fy, Courier ,d Font Family dk uke gSA Font dk tks Logical uke gksrk gS og uke fdlh uk fdlh Specific Font Category dks Specify djrk gSA

tcfd Font Face fdlh uk fdlh Specific Font tSls fd Courier Italic dks Represent djrk gSA Fonts dh fofHkUu fo”ks’krkvksa dks ,d Font uke dh Class esa Encapsulate fd;k x;k gSA bl Font Class esa fuEukuqlkj Variables Defined gSa% Variable String name float pointSize

Meaning Name of the Font Size of the Font in Points


Java in Hindi int size int style

Size of the Font in Points Font Style (Bold, Italic, Normal, BoldItalic)

tc ge Fonts ds lkFk fdlh izdkj dh izfØ;k djrs gSa] rc dbZ ckj gesa ;s tkuus dh t:jr iMrh gS fd gekjs Computer esa dkSu&dkSu ls Fonts miyC/k gSaA bl Information dks izkIr djus ds fy, ge getAvailableFontFamilyNames() Method dk iz;ksx dj ldrs gSaA bl Method dks GraphicsEnvironment uke dh Class esa Define fd;k x;k gSA bl Method dk Syntax fuEukuqlkj gksrk gS% String [ ] getAvailableFontFamilyNames()

;s Method Strings dk ,d Array Return djrk gS] ftlesa Computer ij Available Fonts dh Families ds uke Stored gksrs gSaA blh rjg ls ge getAllFonts() uke ds Method dks Use djds gekjs Computer ij miyC/k fofHkUu izdkj ds Font Objects dks ,d Array ds :i esa izkIr dj ldrs gSaA ;s Method fuEukuqlkj gksrk gS% Font[ ] getAllFonts()

pwafd ;s nksuksa Methods GraphicsEnvironment Class ds Members gSa] blfy, bu Methods dks Call djus ds fy, gesa bl Class ds ,d Reference dh t:jr gksrh gSA bl Class dk Reference izkIr djus ds fy, ge getLocalGraphicsEnvironment() uke ds ,d Static Method dks Call dj ldrs gSaA bldk Syntax fuEukuqlkj gksrk gS% static GraphicsEnvironment getLocalGraphicsEnvironment()

vxys Applet Program esa geus gekjs Computer ij miyC/k fofHkUu Font Families dks izkIr fd;k gSA Program fuEukuqlkj gS% Program // File Name : AllAvailableFonts.java import java.awt.*; import java.applet.*; public class AllAvailableFonts extends Applet{ public void paint(Graphics g) { String message = ""; String FontList[]; GraphicsEnvironment ge=GraphicsEnvironment.getLocalGraphicsEnvironment(); FontList = ge.getAvailableFontFamilyNames(); for(int i=0, j=0; i


Java in Hindi

}

}

}

message = FontList[++i]; g.drawString(message, 315, j);

Output

vius Program esa u;k Font Select djus ds fy, gesa lcls igys ,d u;k Font Object Create djuk gksrk gSA ;s Font Object gh gekjs }kjk Create fd, tkus okys u, Font dks Describe djrk gSA ,d Font Constructor fuEukuqlkj gksrk gS% Font(String fontName, int fontStyle, int pointSize)

bl Constructor esa fontName ml Font dks Specify djrk gS] ftls ge Choose djuk pkgrs gSaA fontName dks ge Font Face uke }kjk Specify dj ldrs gSaA lHkh tkok Environment Dialog, DialogInput, Sans Serif, Serif, Monospaced o Symbol Fonts dks Support djrs gSaA Dialog Font og Font gksrk gS] tks Dialog Boxes esa Use gksrk gSA ;fn ge dksbZ Font Select ugha djrs gSa] rc Hkh Dialog Font Selected gh jgrk gSA Font dh Style dks Specify djus ds fy, ge fontStyle Argument dk iz;ksx djrs gSaA bl Argument esa Font.PLAIN, Font.BOLD o Font.ITALIC esa ls fdlh Style dks Choose fd;k tk ldrk gSA ;fn ge nks Styles dks ,d lkFk Use djuk pkgsa] rks gesa Logical OR Operator

dk fuEukuqlkj iz;ksx djuk gksrk gS% Font.BOLD | Font.ITALIC

;s Statement ,d ,slk Font Create djrk gS] tks Bold o Italic gksrk gSA Font dh Size dks Specify djus ds fy, ge pointSize uke ds Argument esa Font dh Size dks Points esa Specify djrs gSaA


Java in Hindi tks Font geus Create fd;k gS] ml Font dks Set djus ds fy, gesa setFont() Method dk iz;ksx djrs gSaA bl Method dks Component Class esa Define fd;k x;k gS% void setFont(Font fontObj)

bl Syntax esa fontObj og Font Object gksrk gS] ftls Set djus ds fy, geus Choose fd;k gSA Program // File Name: FontSelectionAtRunTime.java import java.awt.*; import java.applet.*; import java.awt.event.*; public class FontSelectionAtRunTime extends Applet{ int next = 0; Font selectedFont; String message; public void init(){ selectedFont = ("Dialog", Font.PLAIN, 15); message = "Dialog"; setFont(selectedFont); addMouseListener(new MyMouseAdapter(this)); }

}

public void paint(Graphics g) { g.drawString(message, 6, 20); }

class MyMouseAdapter extends MouseAdapter{ SampleFonts sample; public MyMouseAdapter(SampleFonts sample) { this.sample = sample; }

}

public void mousePressed(MouseEvent mousEvnt) { sample.next++; switch(sample.next); }


Java in Hindi Last but not Least. There is more…

bl iqLrd esa geus u dsoy Java Language dks Best rjhds ls Describe djus dh dksf”k”k dh gS] cfYd geus ;s ekurs gq, ;s iqLrd fy[kh gS fd vki Object Oriented Programming System (OOPS) ls iwjh rjg ls vufHkK gSa vkSj blhfy, geus bl iqLrd esa dsoy Java ds Programming Concpets dks gh csgrj rjhds ls ugha le>k;k gS] cfYd geus Object Oriented Programming System ds fofHkUu Theoratical Concepts dks Hkh Java Programming Language ds Programs ds ek/;e ls le>kus dh dksf”k”k dh gS fd vki fdl rjg ls OOPS Conepts dks Use djrs gq, Professional Applications Develop dj ldrs gSaA D;ksafd orZeku le; esa Use dh tkus okyh fofHkUu Programming Languages iwjh rjg ls Object Oriented Programming System Pattern ij gh vk/kkfjr gSa vkSj fcuk Object Oriented Programming System dks csgrj rjhds ls le>s gq, vki orZeku le; ds Modern Application Software Develop djus dh {kerk izkIr ugha dj ldrsA gkykafd Object Oriented Programming System ds fofHkUu Concepts vius vki esa dkQh tfVy Concepts gSa] ysfdu Java Programming Language dk iz;ksx djrs gq, bu tfVy OOPS Concepts dks Hkh bl iqLrd esa vklkuh ls le>kus dh dksf”k”k dh xbZ gSA bl iqLrd esa u dsoy Java o OOPS Concepts dks csgrj rjhds ls le>kus dh dksf”k”k dh xbZ gS] cfYd bl ckr dks Hkh le>kus dh dksf”k”k dh xbZ gS fd vki fdl rjg ls fdlh Real World Problem dks fdlh Computer Program esa Convert dj ldrs gSaA rkfd vki fdlh Hkh Real World Problem dks Solve djus ds fy, Professional Levele dk Object Oriented Applicaiotn Software Create dj ldsaA Java Language vius vki esa bruk cMk o Versatile Subject gS fd Java Language ds fodkl ds ckn ftruh Hkh Object Oriented Programming Languages dks fodflr fd;k x;k gS] os lHkh yxHkx “C/C++” Language ds Syntax o Java ds Conceepts ij gh vk/kkfjr jgh gSaA

bruk gh ugha PHP, JavaScript o orZeku le; dh lcls Modern Programming Language C# esa Hkh Java ds Concepts dks yxHkx leku rjhds ls Use fd;k x;k gSA blfy, ;fn vki Java Language dks Bhd ls le>rs gSa] rks vkr C# Programming Langauge dks Hkh cMh gh vklkuh ls lh[k o le> ldrs gSaA mEehn gS] bl iqLrd us vkids Development vkSj Programming ds Kku dks t:j c


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Java in Hindi Updated

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