Sams teach yourself Java 6 in 21 days Includes index

774 Pages·2007·4.907 MB·English

by  Cadenhead, Rogers;Lemay, Laura

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nd win es
DAY 7Exceptions,Assertions,aThreads DAY 14Developing SApplications DAY 21Writing JavaServlets andJava ServerPages Where to Gofrom Here: Java Resourc
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n
DAY 6Packages,Interfaces,aOther ClassFeatures DAY 13Using Color,Fonts,andGraphics DAY 20XML WebServices RegularExpressions
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e
s o
DAY 5Creating Clasand Methods DAY 12Responding tUser Input DAY 19Reading andWriting RSSFeeds CD Writing JavaApplets
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21 Days DAY 4Lists,Logic,andLoops DAY 11ArrangingComponents ona User Interface DAY 18AccessingDatabases withJDBC Bonus Lessons Choosing Java
n
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ava6 DAY 3Working withObjects DAY 10Building a SwiInterface DAY 17CommunicatinAcross theInternet APPENDIX CThis Book's Web Site
J
hYourself a Language DAY 2The ABCs ofProgramming a Class Library DAY 9Working withSwing ogramming DAY 16Serializing andExaminingObjects APPENDIX BProgrammingwith the JavaDevelopment Kit
c v v r
TeaSams The JaWEEK 1: DAY 1Getting Started with Java The JaWEEK 2: DAY 8Data Structures Java PWEEK 3: DAY 15Working withInput and Output Appendixes APPENDIX AUsing the JavaDevelopment Kit
Rogers Cadenhead
Laura Lemay
SamsTeachYourself
Java 6
™
in 21 Days
800 East 96th Street,Indianapolis,Indiana 46240
Sams Teach Yourself Java™ 6 in 21 Days Acquisitions Editor
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Copyright © 2007 by Sams Publishing
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Library of Congress Cataloging-in-Publication Data
Cadenhead,Rogers.
Sams teach yourself Java 6 in 21 days / Rogers Cadenhead,Laura Lemay.
p. cm.
Includes index.
ISBN 978-0-672-32943-2 (pbk. w/cd)
1. Java (Computer program language) I. Lemay,Laura. II. Title.
QA76.73.J38C333 2007
005.13'3--dc22
2007014568
Contents at a Glance
Introduction 1
WEEK I: The Java Language
1 Getting Started with Java 9
2 The ABCs of Programming 35
3 Working with Objects 63
4 Lists,Logic,and Loops 89
5 Creating Classes and Methods 115
6 Packages,Interfaces,and Other Class Features 145
7 Exceptions,Assertions,and Threads 183
WEEK II: The Java Class Library
8 Data Structures 219
9 Working with Swing 247
10 Building a Swing Interface 273
11 Arranging Components on a User Interface 303
12 Responding to User Input 333
13 Using Color,Fonts,and Graphics 357
14 Developing Swing Applications 381
WEEK III: Java Programming
15 Working with Input and Output 405
16 Serializing and Examining Objects 433
17 Communicating Across the Internet 453
18 Accessing Databases with JDBC 485
19 Reading and Writing RSS Feeds 511
20 XML Web Services 535
21 Writing Java Servlets and Java Server Pages 555
Appendixes
A Using the Java Development Kit 601
B Programming with the Java Development Kit 625
C This Book’s Web Site 649
Index 651
Bonus Material on the Companion CD-ROM
CD1 Choosing Java
CD2 Writing Java Applets
CD3 Regular Expressions
CD4 Where to Go from Here: Java Resources
Table of Contents
Introduction 1
How This Book Is Organized ..................................................................................2
Who Should Read This Book ..................................................................................4
Conventions Used in This Book ..............................................................................5
WEEK I: The Java Language
DAY 1: Getting Started with Java 9
The Java Language ..............................................................................................10
History of the Language ..............................................................................10
Introduction to Java ....................................................................................11
Selecting a Development Tool ......................................................................11
Object-Oriented Programming................................................................................12
Objects and Classes..............................................................................................14
Attributes and Behavior........................................................................................17
Attributes of a Class of Objects ....................................................................17
Behavior of a Class of Objects......................................................................18
Creating a Class..........................................................................................19
Running the Program ..................................................................................21
Organizing Classes and Class Behavior....................................................................24
Inheritance ................................................................................................24
Creating a Class Hierarchy ..........................................................................26
Inheritance in Action ..................................................................................28
Single and Multiple Inheritance ....................................................................29
Interfaces ..................................................................................................30
Packages ..................................................................................................30
Summary............................................................................................................31
Q&A ................................................................................................................31
Quiz..................................................................................................................32
Questions..................................................................................................32
Answers....................................................................................................32
Certification Practice ..................................................................................32
Exercises............................................................................................................33
DAY 2: The ABCs of Programming 35
Statements and Expressions ..................................................................................36
Variables and Data Types......................................................................................36
Creating Variables ......................................................................................37
Naming Variables........................................................................................39
Variable Types............................................................................................39
Assigning Values to Variables........................................................................41
Constants..................................................................................................41
Comments..........................................................................................................43
Literals..............................................................................................................44
Number Literals..........................................................................................45
Boolean Literals..........................................................................................46
Character Literals........................................................................................46
String Literals............................................................................................47
Expressions and Operators ....................................................................................48
Arithmetic ................................................................................................49
More About Assignment..............................................................................51
Incrementing and Decrementing....................................................................52
Comparisons..............................................................................................53
Logical Operators ......................................................................................54
Operator Precedence....................................................................................55
String Arithmetic ................................................................................................57
Summary............................................................................................................58
Q&A ................................................................................................................59
Quiz..................................................................................................................60
Questions..................................................................................................60
Answers....................................................................................................60
Certification Practice ..................................................................................60
Exercises............................................................................................................61
DAY 3: Working with Objects 63
Creating New Objects ..........................................................................................64
Usingnew..................................................................................................64
WhatnewDoes ..........................................................................................66
A Note on Memory Management ..................................................................66
vi Sams Teach Yourself Java 6 in 21 Days
Accessing and Setting Class and Instance Variables....................................................67
Getting Values............................................................................................67
Changing Values ........................................................................................68
Class Variables ..........................................................................................69
Calling Methods..................................................................................................70
Nesting Method Calls..................................................................................72
Class Methods............................................................................................73
References to Objects ..........................................................................................74
Casting and Converting Objects and Primitive Types..................................................76
Casting Primitive Types................................................................................77
Casting Objects..........................................................................................78
Converting Primitive Types to Objects and Vice Versa ......................................80
Comparing Object Values and Classes ....................................................................82
Comparing Objects......................................................................................82
Determining the Class of an Object................................................................84
Summary............................................................................................................84
Q&A ................................................................................................................85
Quiz..................................................................................................................86
Questions..................................................................................................86
Answers....................................................................................................86
Certification Practice ..................................................................................86
Exercises............................................................................................................87
DAY 4: Lists,Logic,and Loops 89
Arrays................................................................................................................90
Declaring Array Variables............................................................................90
Creating Array Objects................................................................................91
Accessing Array Elements............................................................................92
Changing Array Elements ............................................................................93
Multidimensional Arrays..............................................................................95
Block Statements ................................................................................................96
ifConditionals ..................................................................................................97
switchConditionals ............................................................................................98
forLoops ........................................................................................................104
Contents vii
whileanddoLoops ..........................................................................................107
whileLoops............................................................................................107
do-whileLoops ......................................................................................109
Breaking Out of Loops........................................................................................109
Labeled Loops..........................................................................................110
The Conditional Operator ..........................................................................110
Summary..........................................................................................................112
Q&A................................................................................................................112
Quiz................................................................................................................112
Questions ................................................................................................112
Answers..................................................................................................113
Certification Practice..................................................................................113
Exercises..........................................................................................................114
DAY 5: Creating Classes and Methods 115
Defining Classes................................................................................................116
Creating Instance and Class Variables....................................................................116
Defining Instance Variables ........................................................................116
Class Variables..........................................................................................117
Creating Methods ..............................................................................................117
Defining Methods......................................................................................118
ThethisKeyword....................................................................................120
Variable Scope and Method Definitions ........................................................121
Passing Arguments to Methods....................................................................122
Class Methods..........................................................................................123
Creating Java Applications ..................................................................................124
Helper Classes..........................................................................................125
Java Applications and Command-line Arguments ....................................................126
Passing Arguments to Java Applications........................................................126
Handling Arguments in Your Java Application................................................127
Creating Methods with the Same Name, Different Arguments....................................128
Constructor Methods ..........................................................................................132
Basic Constructor Methods ........................................................................133
Calling Another Constructor Method............................................................133
Overloading Constructor Methods................................................................134
viii Sams Teach Yourself Java 6 in 21 Days
Overriding Methods............................................................................................136
Creating Methods That Override Existing Methods..........................................136
Calling the Original Method........................................................................137
Overriding Constructors..............................................................................138
Finalizer Methods..............................................................................................140
Summary..........................................................................................................141
Q&A................................................................................................................141
Quiz................................................................................................................142
Questions ................................................................................................142
Answers..................................................................................................143
Certification Practice..................................................................................143
Exercises..........................................................................................................144
DAY 6: Packages,Interfaces,and Other Class Features 145
Modifiers..........................................................................................................146
Access Control for Methods and Variables ....................................................146
Static Variables and Methods................................................................................152
Final Classes, Methods, and Variables....................................................................154
Variables..................................................................................................155
Methods..................................................................................................155
Classes....................................................................................................156
Abstract Classes and Methods..............................................................................156
Packages..........................................................................................................157
Using Packages..................................................................................................157
Full Package and Class Names ....................................................................158
TheimportDeclaration ............................................................................159
Class Name Conflicts ................................................................................160
A Note About Classpathand Where Classes Are Located ..............................161
Creating Your Own Packages ..............................................................................162
Picking a Package Name ............................................................................162
Creating the Folder Structure ......................................................................162
Adding a Class to a Package........................................................................163
Packages and Class Access Control..............................................................163
Interfaces..........................................................................................................164
The Problem of Single Inheritance................................................................164
Interfaces and Classes................................................................................164