Object-Oriented Programming and Data Structures

Transcription

1 Java Methods A & AB Object-Oriented Programming and Data Structures Maria Litvin Phillips Academy, Andover, Massachusetts Gary Litvin Skylight Software, Inc. Skylight Publishing Andover, Massachusetts

2 Skylight Publishing 9 Bartlet Street, Suite 70 Andover, MA web: sales@skylit.com support@skylit.com Copyright 2006 by Maria Litvin, Gary Litvin, and Skylight Publishing All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise, without the prior written permission of the authors and Skylight Publishing. Library of Congress Control Number: ISBN-10: ISBN-13: * AP and Advanced Placement are registered trademarks of The College Board, which was not involved in the production of and does not endorse this book. The names of commercially available software and products mentioned in this book are used for identification purposes only and may be trademarks or registered trademarks owned by corporations and other commercial entities. Skylight Publishing and the authors have no affiliation with and disclaim any sponsorship or endorsement by any of these products manufacturers or trademarks owners. Sun, Sun Microsystems, Java, and Java logos are trademarks or registered trademarks of Sun Microsystems, Inc. in the United States and other countries. SCRABBLE is the registered trademark of HASBRO in the United States and Canada and of J.W. Spear and Sons, PLC, a subsidiary of Mattel, Inc., outside the United States and Canada Printed in the United States of America

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5 Brief Contents Preface xvii How to Use This Book xxi Chapter 1 An Introduction to Hardware, Software, and the Internet 1 Chapter 2 An Introduction to Software Development 11 Chapter 3 Objects and Classes 43 Chapter 4 Algorithms 75 Chapter 5 Java Syntax and Style 103 Chapter 6 Data Types, Variables, and Arithmetic 121 Chapter 7 Boolean Expressions and if-else Statements 153 Chapter 8 Iterative Statements: while, for, do while 193 Chapter 9 Implementing Classes and Using Objects 211 Chapter 10 Strings 259 Chapter 11 Class Hierarchies and Interfaces 287 Chapter 12 Arrays and ArrayLists 321 Chapter 13 Searching and Sorting 363 Chapter 14 Streams and Files 393 Chapter 15 Graphics 409 Chapter 16 GUI Components and Events 433 Chapter 17 Mouse, Keyboard, Sounds, and Images 441 Chapter 18 Big-O Analysis of Algorithms 445 Chapter 19 The Java Collections Framework 465 Chapter 20 Lists and Iterators 507 Chapter 21 Stacks and Queues 527 Chapter 22 Recursion Revisited 547 Chapter 23 Binary Trees 575 Chapter 24 Lookup Tables and Hashing 603 Chapter 25 Heaps and Priority Queues 623 Chapter 26 Design Patterns 637 Appendices 645 Solutions to Selected Exercises 645 Index of Tables and Figures 647 Index 653 v

6 Start Chapter 1 Chapter 2 AB Chapter 3 Chapter 4 Chapter 18 Chapter 5 Chapter 6 Chapter 7 Chapter 8 A Chapter 9 Chapter 10 Chapter 11 Chapter 14 Chapter 15 Chapter 16 Chapter 17 Chapter 19 Chapter 20 Chapter 21 Chapter 22 Chapter 23 Chapter 24 Chapter 25 Chapter 12 Chapter 26 Chapter 13 Finish

7 Contents Preface xvii How to Use This Book xxi Chapter 1. An Introduction to Hardware, Software, and the Internet Prologue Hardware Overview The CPU Memory Secondary Storage Devices Input and Output Devices 1.3 Software Overview 1.4 What Do Programmers Do? 1.5 Representation of Information in Computer Memory Numbers Characters 1.6 The Internet 1.7 Summary Exercises 5 Chapter 2. An Introduction to Software Development Prologue Compilers and Interpreters Software Components and Packages Lab: Three Ways to Say Hello Object-Oriented Programming Lab: More Ways to Say Hello Summary 37 Exercises 38 vii

8 viii CONTENTS Chapter 3. Objects and Classes Prologue Objects in a Program: An Example Classes Fields, Constructors, and Methods Case Study and Lab: First Steps Inheritance Summary 67 Exercises 69 Chapter 4. Algorithms Prologue Properties of Algorithms Iterations Recursion Case Study: Euclid s GCF Algorithm Working with Lists Case Study: File Manager Summary 94 Exercises 95 Chapter 5. Java Syntax and Style Prologue Using Comments Reserved Words and Programmer-Defined Names Syntax vs. Style Statements, Blocks, Indentation Lab: Correcting Syntax Errors Summary 117 Exercises 118

9 CONTENTS ix Chapter 6. Data Types, Variables, and Arithmetic Prologue Declaring Fields and Local Variables Primitive Data Types Strings Constants Scope of Variables Arithmetic Expressions Compound Assignment and Increment Operators Converting Numbers and Objects into Strings Lab: Pie Chart Summary 145 Exercises 146 Chapter 7. Boolean Expressions and if-else Statements Prologue if else Statements boolean Data Type Relational Operators Logical Operators Order of Operators Short-Circuit Evaluation if else if and Nested if else Case Study and Lab: Rolling Dice The switch statement Enumerated Data Types Case Study and Lab: Rolling Dice Concluded Summary 186 Exercises 188 Chapter 8. Iterative Statements: while, for, do-while Prologue The while and for Loops The do while Loop return and break in Loops Nested Loops Lab: Perfect Numbers Summary 205 Exercises 206

10 x CONTENTS Chapter 9. Implementing Classes and Using Objects Prologue Public and Private Features of a Class Constructors References to Objects Defining Methods Calling Methods and Accessing Fields Passing Parameters to Constructors and Methods return Statement Case Study and Lab: Snack Bar Overloaded Methods Static Fields and Methods Case Study and Lab: Snack Bar Concluded Summary 249 Exercises 251 Chapter 10. Strings Prologue Literal Strings String Constructors and Immutability String Methods Formatting Numbers into Strings Extracting Numbers from Strings Character Methods Lab: Lipograms The StringBuffer Class Summary 280 Exercises 281 Chapter 11. Class Hierarchies and Interfaces Prologue Class Hierarchies and Polymorphism Abstract Classes Invoking Superclass s Constructors Calling Superclass s Methods Case Study: Dance Studio Interfaces Case Study: Dance Studio Concluded Summary 314 Exercises 317

11 CONTENTS xi Chapter 12. Arrays and ArrayLists Prologue One-Dimensional Arrays Lab: Fortune Teller The ArrayList Class ArrayList s Constructors and Methods ArrayList s Pitfalls Iterations and the For Each Loop Inserting and Removing Elements Lab: Creating an Index for a Document Two-Dimensional Arrays Case Study and Lab: Chomp Summary 352 Exercises 354 Chapter 13. Searching and Sorting Prologue equals, compareto, and compare Sequential and Binary Search Lab: Keeping Things in Order Selection Sort Insertion Sort Mergesort Quicksort Lab: Benchmarks java.util.arrays and java.util.collections Summary 388 Exercises 390 Chapter 14. Streams and Files Prologue Pathnames and the java.io.file Class Reading from a Text File Writing to a Text File Lab: Choosing Words Summary 404 Exercises 405

12 xii CONTENTS Chapter 15. Graphics Prologue paint, paintcomponent, and repaint Coordinates Colors Drawing Shapes Fonts and Text Case Study and Lab: Pieces of the Puzzle Summary 429 Exercises 430 Chapter 16. GUI Components and Events Prologue Pluggable Look and Feel 16.3 Basic Swing Components and Their Events 16.4 Layouts 16.5 Menus 16.6 Case Study and Lab: the Ramblecs Game 16.7 Summary Exercises 436 Chapter 17. Mouse, Keyboard, Sounds, and Images Prologue Mouse Events Handling 17.3 Keyboard Events Handling 17.4 Case Study and Lab: Drawing Editor 17.5 Sounds and Images 17.6 Case Study and Lab: Ramblecs Concluded 17.7 Summary Exercises 443 Chapter 18. Big-O Analysis of Algorithms Prologue The Big-O Concept Big-O of Sorting Algorithms Summary 459 Exercises 461

13 CONTENTS xiii Chapter 19. The Java Collections Framework Prologue Collection and Iterator Lists and ListIterator The Stack Class The Queue Interface The PriorityQueue Class Sets Maps Case Study and Lab: Stock Exchange Summary 499 Exercises 499 Chapter 20. Lists and Iterators Prologue Singly-Linked List Traversals Lab: Implementing a Singly-Linked List Linked List with a Tail Doubly-Linked List and Circular List Lab: Teletext Summary 522 Exercises 523 Chapter 21. Stacks and Queues Prologue Implementations of Stacks Lab: Browsing The Hardware Stack Implementations of Queues Case Study and Lab: Actors World Summary 541 Exercises 542

14 xiv CONTENTS Chapter 22. Recursion Revisited Prologue Three Examples When Not to Use Recursion Understanding and Debugging Recursive Methods Lab: the Tower of Hanoi Case Study and Lab: the Game of Hex Summary 568 Exercises 568 Chapter 23. Binary Trees Prologue Implementations of Binary Trees Traversals Binary Search Trees A Do-It-Yourself BST Lab: Morse Code Case Study and Lab: Java Messenger Summary 594 Exercises 595 Chapter 24. Lookup Tables and Hashing Prologue Lookup Tables Lab: Cryptogram Solver Hash Tables java.util s HashSet and HashMap Lab: Search Engine Summary 617 Exercises 618 Chapter 25. Heaps and Priority Queues Prologue Implementations of Priority Queues Binary Trees: Non-Linked Representation A Do-It-Yourself Priority Queue Lab: Heapsort Summary 633 Exercises 634

15 CONTENTS xv Chapter 26. Design Patterns Prologue Façade 26.3 Strategy 26.4 Singleton 26.5 Decorator 26.6 Composite 26.7 MVC (Model-View-Controller) 26.8 Summary Exercises 640 Appendices 645 A. The 17 Bits of Style B. Common Syntax Error Messages C. HTML Tutorial D. GUI Examples Index E. The EasyReader, EasyWriter, EasySound, EasyDate, and EasyFormat Classes F. Computing in Context: Responsible and Ethical Computer Use Solutions to Selected Exercises 645 Index of Tables and Figures 647 Index 653

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