Absolute Java

switch Statement 103 Pitfall: Forgetting a break in a switch Statement 107 The Conditional Operator 108 3.2 BOOLEAN EXPRESSIONS 109 Simple Boolean Expressions 109 Pitfall: Using = in Place of == 110 Pitfall: Using == with Strings 111 Lexicographic and Alphabetical Order 112 Building Boolean Expressions 115 Pitfall: Strings of Inequalities 116 Evaluating Boolean Expressions 116 Tip: Naming Boolean Variables 119 Short-Circuit and Complete Evaluation 120 Precedence and Associativity Rules 121 3.3 LOOPS 128 while Statement and do-while Statement 128 Algorithms and Pseudocode 130 Example: Averaging a List of Scores 133 The for Statement 134 The Comma in for Statements 137 Tip: Repeat N Times Loops 139 Pitfall: Extra Semicolon in a for Statement 139 Pitfall: Infinite Loops 140 Nested Loops 141 The break and continue Statements144 The exit Statement 145 3.4 DEBUGGING 146 Loop Bugs 146 Tracing Variables 146 General Debugging Techniques 147 Example: Debugging an Input Validation Loop 148 Preventive Coding 152 Assertion Checks 153 Chapter Summary 155 Answers to Self-Test Exercises 156 Programming Projects 161 Chapter 4 Defining Classes I 167 4.1 CLASS DEFINITIONS 168 Instance Variables and Methods 171 More about Methods 174 Tip: Any Method Can Be Used as a void Method 178 Local Variables 180 Blocks 181 Tip: Declaring Variables in a for Statement 182 Parameters of a Primitive Type 182 Pitfall: Use of the Terms "Parameter" and "Argument" 189 Simple Cases with Class Parameters 191 The this Parameter 191 Methods That Return a Boolean Value 193 The Methods equals and toString 196 Recursive Methods 199 Tip: Testing Methods 199 4.2 INFORMATION HIDING AND ENCAPSULATION 201 public and private Modifiers 202 Example: Yet Another Date Class 203 Accessor and Mutator Methods 204 Tip: A Class Has Access to Private Members of All Objects of the Class 209 Tip: Mutator Methods Can Return a Boolean Value 210 Preconditions and Postconditions 211 4.3 OVERLOADING 212 Rules for Overloading 212 Pitfall: Overloading and Automatic Type Conversion 216 Pitfall: You Cannot Overload Based on the Type Returned 218 4.4 CONSTRUCTORS 220 Constructor Definitions 220 Tip: You Can Invoke Another Method in a Constructor 228 Tip: A Constructor Has a this Parameter 228 Tip: Include a No-Argument Constructor 229 Example: The Final Date Class 230 Default Variable Initializations 231 An Alternative Way to Initialize Instance Variables 231 Example: A Pet Record Class 232 The StringTokenizer Class 236 Chapter Summary 241 Answers to Self-Test Exercises 242 Programming Projects 247 Chapter 5 Defining Classes II 253 5.1 STATIC METHODS AND STATIC VARIABLES 255 Static Methods 255 Pitfall: Invoking a Nonstatic Method Within a Static Method 257 Tip: You Can Put a main in Any Class 258 Static Variables 262 The Math Class 267 Wrapper Classes 271 Automatic Boxing and Unboxing 272 Static Methods in Wrapper Classes 274 Pitfall: A Wrapper Class Does Not Have a No-Argument Constructor 277 5.2 REFERENCES AND CLASS PARAMETERS 278 Variables and Memory 279 References 280 Class Parameters 285 Pitfall: Use of = and == with Variables of a Class Type 289 The Constant null 291 Pitfall: Null Pointer Exception 292 The new Operator and Anonymous Objects 292 Example: Another Approach to Keyboard Input 293 Tip: Use Static Imports 295 5.3 USING AND MISUSING REFERENCES 297 Example: A Person Class 298 Pitfall: null Can Be an Argument to a Method 303 Copy Constructors 307 Pitfall: Privacy Leaks 309 Tip: Deep Copy versus Shallow Copy 315 Mutable and Immutable Classes 313 Tip: Assume Your Coworkers Are Malicious 316 5.4 PACKAGES AND JAVADOC 316 Packages and import Statements 317 The Package java.lang 318 Package Names and Directories 318 Pitfall: Subdirectories Are Not Automatically Imported 321 The Default Package 321 Pitfall: Not Including the Current Directory in Your Class Path 322 Specifying a Class Path When You Compile 322 Name Clashes 323 Introduction to javadoc 324 Commenting Classes for javadoc 324 Running javadoc 326 Chapter Summary 328 Answers to Self-Test Exercises 329 Programming Projects 333 Chapter 6 Arrays 339 6.1 INTRODUCTION TO ARRAYS 340 Creating and Accessing Arrays 341 The length Instance Variable 344 Tip: Use for Loops with Arrays 346 Pitfall: Array Indices Always Start with Zero 346 Pitfall: Array Index Out of Bounds 346 Initializing Arrays 347 Pitfall: An Array of Characters Is Not a String 349 6.2 ARRAYS AND REFERENCES 350 Arrays Are Objects 350 Pitfall: Arrays with a Class Base Type 352 Array Parameters 352 Pitfall: Use of = and == with Arrays 354 Arguments for the Method main 359 Methods that Return an Array 361 6.3 PROGRAMMING WITH ARRAYS 362 Partially Filled Arrays 363 Example: A Class for Partially Filled Arrays 366 Tip: Accessor Methods Need Not Simply Return Instance Variables 370 The "for-each" Loop 370 Methods with a Variable Number of Parameters 374 Example: A String Processing Example 377 Privacy Leaks with Array Instance Variables 378 Example: Sorting an Array 382 Enumerated Types 386 Tip: Enumerated Types in switch Statements 391 6.4 MULTIDIMENSIONAL ARRAYS 393 Multidimensional Array Basics 393 Using the length Instance Variable 396 Ragged Arrays 397 Multidimensional Array Parameters and Returned Values 397 Example: A Grade Book Class 398 Chapter Summary 404 Answers to Self-Test Exercises 405 Programming Projects 412 Chapter 7 Inheritance 419 7.1 INHERITANCE BASICS 420 Derived Classes 421 Overriding a Method Definition 431 Changing the Return Type of an Overridden Method 431 Changing the Access Permission of an Overridden Method 432 Pitfall: Overriding versus Overloading 433 The super Constructor 434 The this Constructor 436 Tip: An Object of a Derived Class Has More than One Type 437 Pitfall: The Terms Subclass and Superclass 440 Example: An Enhanced StringTokenizer Class 441 7.2 ENCAPSULATION AND INHERITANCE 444 Pitfall: Use of Private Instance Variables from the Base Class 444 Pitfall: Private Methods Are Effectively Not Inherited 446 Protected and Package Access 446 Pitfall: Forgetting about the Default Package 448 Pitfall: A Restriction on Protected Access 450 7.3 PROGRAMMING WITH INHERITANCE 452 Tip: Static Variables Are Inherited 452 Tip: "is a" Versus "has a" 453 Access to a Redefined Base Method 453 Pitfall: You Cannot Use Multiple supers 454 The Class Object 455 The Right Way to Define equals 456 Tip: getClass Versus instanceof 459 Chapter Summary 464 Answers to Self-Test Exercises 465 Programming Projects 468 Chapter 8 Polymorphism and Abstract Classes 473 8.1 POLYMORPHISM 474 Late Binding 475 The final Modifier 477 Example: Sales Records 478 Late Binding with toString 485 Pitfall: No Late Binding for Static Methods 486 Downcasting and Upcasting 487 Pitfall: Downcasting 491 Tip: Checking to See Whether Downcasting Is Legitimate 491 A First Look at the clone Method 494 Pitfall: Sometimes the clone Method Return Type Is Object 495 Pitfall: Limitations of Copy Constructors 496 8.2 ABSTRACT CLASSES 500 Abstract Classes 500 Pitfall: You Cannot Create Instances of an Abstract Class 505 Tip: An Abstract Class Is a Type 505 Chapter Summary 507 Answers to Self-Test Exercises 507 Programming Projects 509 Chapter 9 Exception Handling 513 9.1 EXCEPTION HANDLING BASICS 515 Example: A Toy Example of Exception Handling 515 try-throw-catch Mechanism 520 Exception Classes 524 Exception Classes from Standard Packages 525 Defining Exception Classes 527 Tip: Preserve getMessage 531 Tip: An Exception Class Can Carry a Message of Any Type 533 Multiple catch Blocks 538 Pitfall: Catch the More Specific Exception First 540 9.2 THROWING EXCEPTIONS IN METHODS 542 Throwing an Exception in a Method 543 Declaring Exceptions in a throws Clause 545 Exceptions to the Catch or Declare Rule 547v throws Clause in Derived Classes 549 When to Use Exceptions 549 Event-Driven Programming 551 9.3 MORE PROGRAMMING TECHNIQUES FOR EXCEPTION HANDLING 552 Pitfall: Nested try-catch Blocks 553 The finally Block 553 Rethrowing an Exception 555 The AssertionError Class 555 Exception Handling with the Scanner Class 555 Tip: Exception Controlled Loops 556 ArrayIndexOutOfBoundsException 558 Chapter Summary 558 Answers to Self-Test Exercises 559 Programming Projects 563 Chapter 10 File I/O 567 10.1 INTRODUCTION TO FILE I/O 568 Streams 569 Text Files and Binary Files 569 10.2 TEXT FILES 570 Writing to a Text File 570 Pitfall: A try Block Is a Block 576 Pitfall: Overwriting an Output File 577 Appending to a Text File 577 Tip: toString Helps with Text File Output 578 Reading from a Text File 580 Reading a Text File Using Scanner 580 Testing for the End of a Text File with Scanner 583 Reading a Text File Using BufferedReader 590 Tip: Reading Numbers with BufferedReader 594 Testing for the End of a Text File with BufferedReader 594 Path Names 597 Nested Constructor Invocations 598 System.in, System.out, and System.err 598 10.3 THE FILE CLASS 600 Programming with the File Class 601 10.4 BINARY FILES 604 Writing Simple Data to a Binary File 605 UTF and writeUTF 609 Reading Simple Data from a Binary File 610 Checking for the End of a Binary File 615 Pitfall: Checking for the End of a File in the Wrong Way 617 Binary I/O of Objects 618 The Serializable Interface 618 Pitfall: Mixing Class Types in the Same File 621 Array Objects in Binary Files 622 10.5 RANDOM ACCESS TO BINARY FILES 624 Reading and Writing to the Same File 624 Pitfall: A RandomAccessFile Need Not Start Empty 630 Chapter Summary 630 Answers to Self-Test Exercises 631 Programming Projects 635 Chapter 11 Recursion 639 11.1 RECURSIVE VOID METHODS 641 Example: Vertical Numbers 641 Tracing a Recursive Call 644 A Closer Look at Recursion 647 Pitfall: Infinite Recursion 649 Stacks for Recursion 650 Pitfall: Stack Overflow 652 Recursion versus Iteration 652 11.2 RECURSIVE METHODS THAT RETURN A VALUE 653 General Form for a Recursive Method That Returns a Value 653 Example: Another Powers Method 654 11.3 THINKING RECURSIVELY 659 Recursive Design Techniques 659 Binary Search 650 Efficiency of Binary Search 666 Chapter Summary 668 Answers to Self-Test Exercises 669 Programming Projects 672 Chapter 12 UML and Patterns 677 12.1 UML 678 History of UML 679 UML Class Diagrams 679 Class Interactions 680 Inheritance Diagrams 680 More UML 682 12.2 PATTERNS 683 Adaptor Pattern 683 The Model-View-Controller Pattern 684 Example: A Sorting Pattern 685 Restrictions on the Sorting Pattern 691 Efficiency of the Sorting Pattern 691 Tip: Pragmatics and Patterns 692 Pattern Formalism 692 Chapter Summary 693 Answers to Self-Test Exercises 693 Programming Projects 695 Chapter 13 Interfaces and Inner Classes 699 13.1 INTERFACES 701 Interfaces 701 Abstract Classes Implementing Interfaces 703 Derived Interfaces 703 Pitfall: Interface Semantics Are Not Enforced 705 The Comparable Interface 707 Example: Using the Comparable Interface 708 Defined Constants in Interfaces 713 Pitfall: Inconsistent Interfaces 714 The Serializable Interface 717 The Cloneable Interface 717 13.2 SIMPLE USES OF INNER CLASSES 722 Helping Classes 722 Tip: Inner and Outer Classes Have Access to Each Other's Private Members 723 Example: A Bank Account Class 723 The .class File for an Inner Class 727 Pitfall: Other Uses of Inner Classes 728 13.3 MORE ABOUT INNER CLASSES 728 Static Inner Classes 728 Public Inner Classes 729 Tip: Referring to a Method of the Outer Class 731 Nesting Inner Classes 733 Inner Classes and Inheritance 733 Anonymous Classes 734 Tip: Why Use Inner Classes? 736v Chapter Summary 737 Answers to Self-Test Exercises 738 Programming Projects 742 Chapter 14 Generics and the ArrayList Class 747 14.1 THE ARRAYLIST CLASS 749 Using the ArrayList Class 750 Tip: Summary of Adding to an ArrayList 754 Methods in the Class ArrayList 755 The "for-each" Loop 759 Example: Golf Scores 762 Tip: Use trimToSize to Save Memory 765 Pitfall: The clone Method Makes a Shallow Copy 765 The Vector Class 766 Parameterized Classes and Generics 767 Pitfall: Nonparameterized ArrayList and Vector Classes 767 14.2 GENERICS 767 Generic Basics 767 Tip: Compile with the -Xlint Option 769 Example: A Generic Class for Ordered Pairs 770 Pitfall: A Generic Constructor Name Has No Type Parameter 773 Pitfall: You Cannot Plug in a Primitive Type for a Type Parameter 774 Pitfall: A Type Parameter Cannot Be Used Everywhere a Type Name Can Be Used 774 Pitfall: An Instantiation of a Generic Class Cannot be an Array Base Type 774 Tip: A Class Definition Can Have More Than One Type Parameter 775 Pitfall: A Generic Class Cannot Be an Exception Class 777 Bounds for Type Parameters 778 Tip: Generic Interfaces 780 Generic Methods 780 Inheritance with Generic Classes 782 Chapter Summary 784 Answers to Self-Test Exercises 785 Programming Projects 787 Chapter 15 Linked Data Structures 791 15.1 JAVA LINKED LISTS 794 Example: A Simple Linked List Class 794 Working with Linked Lists 798 Pitfall: Privacy Leaks 803 Node Inner Classes 804v Example: A Generic Linked List 807 Pitfall: Using Node Instead of Node 812 The equals Method for Linked Lists 813 15.2 COPY CONSTRUCTORS AND THE CLONE METHOD 814 Simple Copy Constructors and clone Methods 815 Exceptions 815 Pitfall: The clone Method Is Protected in Object 818 Tip: Use a Type Parameter Bound for a Better clone 819 Example: A Linked List with a Deep Copy clone Method 822 Tip: Cloning Is an "All or Nothing" Affair 826 15.3 ITERATORS 826 Defining an Iterator Class 827 Adding and Deleting Nodes 832 15.4 VARIATIONS ON A LINKED LIST 835 Doubly Linked List 837 The Stack Data Structure 846 The Queue Data Structure 848 Running Times and Big-O Notation 851 Efficiency of Linked Lists 856 15.5 HASH TABLES WITH CHAINING 857 A Hash Function for Strings 858 Efficiency of Hash Tables 862 15.6 SETS 863 Fundamental Set Operations 863 Efficiency of Sets Using Linked Lists 868 15.7 TREES 869 Tree Properties 870 Example: A Binary Search Tree Class 872 Efficiency of Binary Search Trees 878 Chapter Summary 879 Answers to Self-Test Exercises 880 Programming Projects 885 Chapter 16 Collections, Maps and Iterators 889 16.1 COLLECTIONS 890 Wildcards 892 The Collection Framework 892 Pitfall: Optional Operations 898 Tip: Dealing with All Those Exceptions 899 Concrete Collection Classes 900 Differences Between ArrayList and Vector 909 Nonparameterized Version of the Collection Framework 909 Pitfall: Omitting the 910 16.2 MAPS 910 Concrete Map Classes 913 16.3 ITERATORS 917 The Iterator Concept 917 The Iterator Interface 917 Tip: For-Each Loops as Iterators 920 List Iterators 921 Pitfall: next Can Return a Reference 923 Tip: Defining Your Own Iterator Classes 925 Chapter Summary 926 Answers to Self-Test Exercises 926 Programming Projects 927 Chapter 17 Swing I 933 17.1 EVENT-DRIVEN PROGRAMMING 935 Events and Listeners 935 17.2 BUTTONS, EVENTS, AND OTHER SWING BASICS 936 Example: A Simple Window 937 Pitfall: Forgetting to Program the Close-Window Button 942 Buttons 943 Action Listeners and Action Events 944 Pitfall: Changing the Heading for actionPerformed 946 Tip: Ending a Swing Program 947 Example: A Better Version of Our First Swing GUI 947 Labels 951 Color 952 Example: A GUI with a Label and Color 953 17.3 CONTAINERS AND LAYOUT MANAGERS 956 Border Layout Managers 956 Flow Layout Managers 959 Grid Layout Managers 961 Panels 965 Example: A Tricolor Built with Panels 966 The Container Class 970 Tip: Code a GUI's Look and Actions Separately 973 The Model-View-Controller Pattern 974 17.4 MENUS AND BUTTONS 975 Example: A GUI with a Menu 975 Menu Bars, Menus, and Menu Items 975 Nested Menus 980 The AbstractButton Class 980 The setActionCommand Method 983 Listeners as Inner Classes 985 17.5 TEXT FIELDS AND TEXT AREAS 988 Text Areas and Text Fields 988 Tip: Labeling a Text Field 994 Tip: Inputting and Outputting Numbers 995 A Swing Calculator 995 Chapter Summary 1001 Answers to Self-Test Exercises 1002 Programming Projects 1009 Chapter 18 Swing II 1011 18.1 WINDOW LISTENERS 1012 Example: A Window Listener Inner Class 1014 The dispose Method 1018 Pitfall: Forgetting to Invoke setDefaultCloseOperation 1018 The WindowAdapter Class 1019 18.2 ICONS AND SCROLL BARS 1020 Icons 1020 Scroll Bars 1027 Example: Components with Changing Visibility 1033 18.3 THE GRAPHICS CLASS 1036 Coordinate System for Graphics Objects 1037 The Method paint and the Class Graphics 1037 Drawing Ovals 1043 Drawing Arcs 1043 Rounded Rectangles 1047 paintComponent for Panels 1048 Action Drawings and repaint 1048 Some More Details on Updating a GUI 1054 18.4 COLORS 1054 Specifying a Drawing Color 1055 Defining Colors 1056 Pitfall: Using doubles to Define a Color 1057 The JColorChooser Dialog Window 1058 18.5 FONTS AND THE DRAWSTRING METHOD 1061 The drawString Method 1061 Fonts 1064 Chapter Summary 1067 Answers to Self-Test Exercises 1068 Programming Projects 1071 Chapter 19 Java Never Ends 1077 19.1 MULTITHREADING 1078 Example: A Nonresponsive GUI 1079 Thread.sleep 1079 The getGraphics Method 1083 Fixing a Nonresponsive Program Using Threads 1084 Example: A Multithreaded Program 1084 The Class Thread 1085 The Runnable Interface 1088 19.2 NETWORKING WITH STREAM SOCKETS 1091 Sockets 1091 Sockets and Threading 1095 19.3 JAVABEANS 1096 The Component Model 1096 The JavaBeans Model 1096 19.4 JAVA AND DATABASE CONNECTIONS 1098 Relational Databases 1098 Java DB and JDBC 1098 SQL 1100 19.5 WEB PROGRAMMING WITH JAVA SERVER PAGES 1110 Applets, Servlets, and Java Server Pages 1110 Sun GlassFish Enterprise Server 1112 HTML Forms--the Common Gateway Interface 1113 JSP Declarations, Expressions, Scriptlets, and Directives 1115 Chapter Summary 1124 Answers to Self-Test Exercises 1124 Programming Projects 1126 Chapter 20 Applets and HTML (online at www.aw.com/savitch ) Appendix 1 Keywords 1131 Appendix 2 Precedence and Associativity Rules 1133 Appendix 3 Unicode Character Set 1135 Appendix 4 Format Specifications for printf 1137 Appendix 5 Summary of Classes and Interfaces 1139 Index 1207