Java Programming Fundamentals JVPG-SSMN-0101A Java Programming Fundamentals JVPG-SSMN-0101A ©1988-2000 Wave Technologies International, Inc., a Thomson Learning company. Thomson Learning™ is a trademark used herein under license. All rights reserved. Printed in the United States of America. No part of this book may be used or reproduced in any form or by any means, or stored in a database or retrieval system, without prior written permission of the publisher. Making copies of any part of this book for any purpose other than your own personal use is a violation of United States copyright laws. For information, contact Wave Technologies International, Inc., 10845 Olive Blvd., Suite 250, St. Louis, Missouri 63141. This book is sold as is, without warranty of any kind, either express or implied, respecting the contents of this book, including, but not limited to, implied warranties for the book’s quality, performance, merchantability, or fitness for any particular purpose. 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Mention of any products in this book in no way constitutes an endorsement by Wave Technologies International, Inc. 10 9 8 7 6 5 4 3 2 1 iii SELF-STUDY Contents Introduction 1 Course Purpose 1 Course Goals 1 Exercises 2 Scenario-Based Learning 3 Multimedia Overview 3 Videos 3 Assessment 4 Hardware and Software Requirements 4 Chapter 1—Java Runtime Environment 5 Objectives 6 Pre-Test Questions 6 Introduction 7 The Java Virtual Machine 7 The Java 2 Software Development Kit 8 Installation 8 Windows 95/98/Me 9 Windows NT/2000 9 Linux 10 Creating a Simple, Stand-Alone Application 11 Creating a Simple Applet 13 Java Comments 14 Sun Certification 15 Summary 16 Post-Test Questions 16 Chapter 2—Data Types, Variables and Operators 17 Objectives 18 Pre-Test Questions 18 Introduction 19 Data Types 19 Variables 20 Default variable values 21 Variable declaration and initialization 21 Casting 22 iv Contents Operators 24 Arithmetic operators 24 Relational operators 25 Logical operators 26 Precedence 27 Sun Certification 28 Summary 29 Post-Test Questions 30 Chapter 3—Control Statements 33 Objectives 34 Pre-Test Questions 34 Introduction 34 Code Blocks 35 Expressions 36 Conditional Statements 38 if statement 38 switch/case statement 40 Iteration (Loop) Statements 42 while loop (entry condition loop) 42 do while loop (exit condition loop) 43 for loop 43 Nested loops (break and continue) 44 Exercise 3-1: Using while and for loops 46 Sun Certification 47 Summary 48 Post-Test questions 48 Chapter 4—Methods 49 Objectives 50 Pre-Test Questions 50 Introduction 51 Methods 51 Return Statement 53 Calling a Method 55 Parameters 57 Pass by Value 58 Overloading 60 Exercise 4-1: Writing methods 62 Sun Certification 63 Summary 64 Post-Test Questions 64 Contents v Chapter 5—Arrays 65 Objectives 66 Pre-Test Questions 66 Introduction 67 What Is an Array? 67 Initializing an Array 68 Using an Array 70 Passing an Array to a Method 74 Methods with an Array Return Type 75 Garbage Collection 76 Command Line Parameters 78 Exercise 5-1: Using arrays 79 Graduating Task #1: Creating a binary search 79 Sun Certification 81 Summary 83 Post-Test Questions 83 Chapter 6—Classes and Objects 85 Objectives 86 Pre-Test Questions 86 Introduction 87 Object-Oriented Programming 87 What Is a Class? 88 What Is an Object? 89 Instance and Class Members 89 Instance members 90 Class members 93 Abstraction 95 Object References 96 Exercise 6-1: Creating your own classes 98 Sun Certification 99 Summary 100 Post-Test Questions 101 Chapter 7—Inheritance 103 Objectives 104 Pre-Test Questions 104 Introduction 105 What Is Inheritance? 105 Using inheritance 106 Extending Classes 107 Using this and super() 110 The instanceof Operator 111 vi Contents Overriding Methods 112 Exercise 7-1: Implementing inheritance 113 Sun Certification 114 Summary 116 Post-Test Questions 117 Chapter 8—Constructors 119 Objectives 120 Pre-Test Questions 120 Introduction 121 What Is a Constructor? 121 What can constructors do? 122 Using Constructors 123 This 126 this() as a constructor 126 Avoiding namespace conflicts 127 Super 128 Constructor Process 129 Constructors and Callbacks 130 Strings and StringBuffer 132 String constructors 132 String characteristics 133 Methods of String 135 StringBuffer 136 Exercise 8-1: Building constructors 137 Exercise 8-2: Implementing callbacks 138 Sun Certification 139 Summary 142 Post-Test Questions 143 Chapter 9—Interfaces and Abstract Classes 145 Objectives 146 Pre-Test Questions 146 Introduction 147 What Is an Interface? 147 Contents of an interface 148 Interface functions 149 Polymorphism 151 What Is an Abstract Class? 158 Graduating Task #2: Interfaces and Polymorphism 161 Sun Certification 161 Summary 162 Post-Test Questions 162 Contents vii Chapter 10—Packages and Access Modifiers 163 Objectives 164 Pre-Test Questions 164 Introduction 165 Packages and Access Modifiers 165 Packages 165 Access modifiers 167 Comparison Between Java 1.1 And Java 2 168 Information Hiding 169 Encapsulation 171 Exercise 10-1: Using encapsulation, accessors and mutators 173 Sun Certification 173 Summary 174 Post-Test Questions 175 Chapter 11—Swing Components 177 Objectives 178 Pre-Test Questions 178 Introduction 179 What Is the AWT? 179 Heavyweight components (peer pattern) 180 AWT 1.1 180 What Is Swing? 181 Model View Controller (MVC) programming paradigm 182 Basic Swing Components 183 Graphical widgets 185 Containers 203 JavaBeans 207 Sun Certification 208 Summary 208 Post-Test Questions 209 Chapter 12—Layout Managers 211 Objectives 212 Pre-Test Questions 212 Introduction 213 What Is a Layout Manager? 213 FlowLayout 214 GridLayout 216 BorderLayout 218 BoxLayout 221 viii Contents Swing 223 Strut 223 Glue 225 Combining layouts 227 Graduating Task #3: Creating sophisticated layouts 230 Sun Certification 231 Summary 232 Post-Test Questions 232 Chapter 13—Graphics 233 Objectives 234 Pre-Test Questions 234 Introduction 235 What Are Graphics in Java? 235 Graphics Class 236 drawString() 244 drawLine() 244 drawRect() 245 drawImage() 247 Color class 248 Font class 250 Exercise 13-1: Drawing to your Scribble JFrame 252 Sun Certification 253 Summary 253 Post-Test Questions 254 Chapter 14—The Delegation Model 257 Objectives 258 Pre-Test Questions 258 Introduction 259 What Is an Event? 259 SDK 1.3 Event Handling 260 Generating the event object 261 Sending the event object to the listener 261 Preparing the listener to receive the event 262 Example: Creating a closeable JFrame 263 JFrame convenience methods for event handling 268 Example: Event handling and callbacks 269 Sun Certification 274 Summary 274 Post-Test Questions 275 Contents ix Chapter 15—Inner Classes 277 Objectives 278 Pre-Test Questions 278 Introduction 279 What Is an Inner Class? 279 Inner Classes for Event Handling 282 Graduating Task #4: Event-enabling the Scribble Application 286 Sun Certification 287 Summary 289 Post-Test Questions 290 Chapter 16—Applets 291 Objectives 292 Pre-Test Questions 292 Introduction 293 Applets and Web Browsers 294 JApplets 294 Applet life cycle 295 The <APPLET></APPLET> tags 296 Passing parameters to applets 298 Applets should not be trusted 300 Converting an Application into an Applet 301 Converting an Applet into an Application 306 Exercise 16-1: Converting the Scribble application into an applet 308 Sun Certification 308 Summary 309 Post-Test Questions 309 Chapter 17—Exceptions 311 Objectives 312 Pre-Test Questions 312 Introduction 313 What Is an Exception? 313 Errors 314 Exceptions 314 When Bad Things Happen to Good Programs 316 Ignoring the Exception 316 Handling the Exception 317 Throwing the Exception to the calling method 319 Handling and rethrowing the Exception 320 Creating and Throwing Your Own Exceptions 321 xContents Exception Handling Tips 324 Sun Certification 325 Summary 326 Post-Test Questions 326 Chapter 18—Creating Threads and Thread Methods 327 Objectives 328 Pre-Test Questions 328 Introduction 329 What Are Threads? 329 How Operating Systems Handle Multitasking 330 Types of Threads in Java 330 Creating Threads 332 Subclassing the Thread class 332 Implementing the Runnable interface 335 Which technique? 337 Thread states 339 The currentThread(), getName() and sleep() methods 341 The setName() and setPriority() methods 343 The yield() method 345 Graduating Task #5: Creating a threaded digital clock 346 Sun Certification 347 Summary 347 Post-Test Questions 348 Chapter 19—Synchronization 351 Objectives 352 Pre-Test Questions 352 Introduction 353 What Is Thread Synchronization? 353 Thread Racing 353 Synchronized and the Object Monitor 355 Thread Race Condition 356 Competing for resources 357 Synchronizing the methods 359 Atomic processes 360 Sophisticated Thread Synchronization 361 Consumer/producer scenario 362 Deadlocks 368 Graduating Task #6: Enhancing the Digital Clock with Advanced Thread Techniques 369 Sun Certification 370 Summary 370 Post-Test Questions 371 [...]... by going to the command prompt and invoking the Java interpreter java: java HelloWorld Note that you type java HelloWorld, not java HelloWorld.class When you enter the proper command, the JVM will display "Hello World!" in a command line window The Java application development cycle is shown in Figure 1-1 Text Editor javac * .java java *.class Figure 1-1: Java development cycle Output Window Creating... class You must save the program with your text editor as HelloWorld .java (giving it the same name as your class), and compile it using a Java compiler You can use the Javac program if you have the Java 2 Software Development Kit (SDK) supplied by Sun javac HelloWorld .java The Java compiler converts your source code (saved as HelloWorld .java, a text file) to the HelloWorld.class file This *.class file... a file compiled into bytecode 11 12 Chapter 1 Java Runtime Environment Bytecode is another element that makes Java different from other programming languages Other compiled programming languages generate machine dependent binaries, which are files that contain native machine language statements To make Java portable, the Javac compiler generates bytecode Java bytecode is composed of an instruction set... operating system In this chapter we will walk through a basic installation of the Java Development Kit (JDK) and the creation, compilation and execution of a small Java program THE JAVA VIRTUAL MACHINE The Java Virtual Machine (JVM) separates Java from most other programming languages One of the primary design goals of the Java language is to enable the same code to run on any platform The JVM is a software... polymorphism Describe method overloading and overriding Use Java static and instance members 1 Introduction 2 Create Java constructors Identify the differences between instance and class members Use Java abstract classes and interfaces Use Java Strings and StringBuffers Describe Java packages and accessibility Use the Java Abstract Windowing Toolkit (AWT) and Swing components... Microsoft Internet Explorer 5.5 or higher Java Development Kit version 1.2.2 or higher ( http:/ /java. sun.com ) 1 Java Runtime Environment MM AJJO R T O P IICCSS A OR P Objectives 6 Pre-Test Questions 6 Introduction 7 The Java Virtual Machine 7 The Java 2 Software Development Kit 8 Installation 8 Creating a Simple Applet 13 Java Comments 14 Sun Certification... comment /* … */ Javadoc comment /** … */ Sun Certification The following code shows examples of all three comment types: class HelloWorld { //** This is a javadoc comment It is a multiline commment unique to Java If you use the javadoc utility (which comes with Java) , it will automatically create HTML-based documentation for you The online help that comes with the Sun SDK was created using javadoc comments... interpretation, Java is considered to be a hybrid language Note that many compilers exist that will compile Java code into a native format If this is done, the compiled program will not be portable; however, the program will execute without the virtual machine 7 Chapter 1 Java Runtime Environment THE JAVA 2 SOFTWARE DEVELOPMENT KIT The development platform used in this course is the Java 2 Software... Edition, v 1.2.2 or higher The Java 2 SDK was previously known as the Java Development Kit (JDK) 1.2, and it is backward compatible with JDK 1.1 It contains several components, including: 8 The Java Runtime Environment (JRE), which provides the JVM The development tools and compilation libraries necessary to create Java applications and applets This grouping includes the Java compiler, debugging programs... open a Java- enabled browser (the latest Netscape or Internet Explorer should work) and point it to the file that you just saved It should open with the text “Hello World” in the window JAVA COMMENTS When programming, it will be useful to add comments to your code Java supports three types of comments; two will be recognizable to those familiar with C or C++, and the third type is unique to Java The . Java Programming Fundamentals JVPG-SSMN-0101A Java Programming Fundamentals JVPG-SSMN-0101A ©1988-2000 Wave. installation of the Java Development Kit (JDK) and the creation, compilation and execution of a small Java program. THE JAVA VIRTUAL MACHINE The Java Virtual