Table Of Content™
EXAMPLES
IN A NUTSHELL
A Tutorial Companion
to Java in a Nutshell
Learning Java
Java Threads
Java Network Programming
Java Virtual Machine
Java AWT Reference
Java Language Reference
Java Fundamental Classes Reference
Database Programming with JDBC and Java
Java Distributed Computing
Developing Java Beans
Java Security
Java Cryptography
Java Swing
Java Servlet Programming
Java I/O
Java 2D Graphics
Enterprise JavaBeans
Creating Effective JavaHelp
Java and XML
Java Performance Tuning
Also from O’Reilly
Java in a Nutshell
Java Examples in a Nutshell
Java Enterprise in a Nutshell
Java Foundation Classes in a Nutshell
Java Power Reference: A Complete Searchable Resource on CD-ROM
™
EXAMPLES
IN A NUTSHELL
A Tutorial Companion
to Java in a Nutshell
Second Edition
David Flanagan
Beijing •Cambridge •Farnham •Köln •Paris •Sebastopol •Taipei •Tokyo
Java™Examples in a Nutshell, Second Edition
by David Flanagan
Copyright © 2000, 1997 O’Reilly & Associates, Inc. All rights reserved.
Printed in the United States of America.
Published by O’Reilly & Associates, Inc., 101 Morris Street, Sebastopol, CA 95472.
Editor: Paula Ferguson
Production Editor: Mary Anne Weeks Mayo
Cover Designer: Edie Freedman
Printing History:
September 1997: First Edition.
September 2000: Second Edition.
Nutshell Handbook, the Nutshell Handbook logo, and the O’Reilly logo are
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Library of Congress Cataloging-in-Publication Data
Flanagan, David.
Java examples in a nutshell / David Flanagan.--2nd ed.
p.cm.-- (A Nutshell handbook) (The Java series)
Includes index.
ISBN 1-596-00039-1
1.Java (Computer program language) I.Title. II.Series. III.Java series (O’Reilly &
Associates)
QA76.73.J38 F5518 2000
005.13'3--dc21 00-045274
ISBN: 0-596-00039-1
[M]
About the Author
David Flanagan is a computer programmer who spends most of his time writing
about Java. His other books with O’Reilly & Associates include the bestselling Java
inaNutshell, JavaFoundationClassesinaNutshell, JavaEnterpriseinaNutshell,
JavaPowerReference,JavaScript:TheDefinitiveGuide,andJavaScriptPocketRefer-
ence. David has a degree in computer science and engineering from the
MassachusettsInstituteofTechnology.HeliveswithhispartnerChristieintheU.S.
Pacific Northwest between the cities of Seattle, Washington and Vancouver, British
Columbia.
Colophon
Ourlookistheresultofreadercomments,ourownexperimentation,andfeedback
fromdistributionchannels.Distinctivecoverscomplementourdistinctiveapproach
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TheanimalfeaturedonthecoverofJavaExamplesinaNutshell,SecondEdition,is
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mississippiensis), found in the southeastern coastal plain of the United States, and
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Yangtze River. Both alligators are related to the more widely distributed crocodile.
The alligator is a much-studied animal, and so a great deal is known about its life
cycle. Female alligators lay 30 to 80 eggs at a time. The mother allows the sun to
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MaryAnneWeeksMayowasthecopyeditorandproductioneditorforJavaExamples
in a Nutshell, Second Edition. Emily Quill, Madeleine Newell, and Jane Ellin pro-
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Wheneverpossible,ourbooksuseadurableandflexiblelay-flatbinding.Ifthepage
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Ta ble of Contents
Preface .................................................................................................................... xiii
Part I: Core Java APIs
Chapter 1—Java Basics .................................................................................. 3
Hello World ............................................................................................. 3
FizzBuzz .................................................................................................. 7
The Fibonacci Series ............................................................................. 10
Using Command-Line Arguments ........................................................ 10
Echo in Reverse .................................................................................... 11
FizzBuzz Switched ................................................................................ 12
Computing Factorials ............................................................................ 13
Recursive Factorials .............................................................................. 14
Caching Factorials ................................................................................. 15
Computing Big Factorials ..................................................................... 16
Handling Exceptions ............................................................................. 17
Interactive Input .................................................................................... 18
Using a StringBuffer .............................................................................. 19
Sorting Numbers ................................................................................... 21
Computing Primes ................................................................................ 22
Exercises ................................................................................................ 23
v
13 September 2000 10:02
Chapter 2—Objects, Classes, and Interfaces ................................. 24
A Rectangle Class .................................................................................. 25
Testing the Rect Class ........................................................................... 26
A Rect Subclass ..................................................................................... 27
Another Subclass ................................................................................... 27
Complex Numbers ................................................................................ 28
Computing Pseudo-Random Numbers ................................................ 30
Computing Statistics .............................................................................. 32
A Linked List Class ................................................................................ 33
Advanced Sorting .................................................................................. 36
Exercises ................................................................................................ 42
Chapter 3—Input/Output ......................................................................... 44
Files and Streams .................................................................................. 44
Working with Files ................................................................................ 48
Copying File Contents .......................................................................... 49
Reading and Displaying Text Files ...................................................... 52
Listing Directory and File Information ................................................. 55
Compr essing Files and Directories ...................................................... 60
Filtering Character Streams ................................................................... 62
Filtering Lines of Text ........................................................................... 64
A Custom HTML Output Stream .......................................................... 65
Exercises ................................................................................................ 68
Chapter 4—Threads ....................................................................................... 70
Thr ead Basics ........................................................................................ 71
Thr eads and Thread Groups ................................................................ 72
Deadlock ............................................................................................... 75
Timers .................................................................................................... 77
Exercises ................................................................................................ 82
Chapter 5—Networking .............................................................................. 84
Downloading the Contents of a URL ................................................... 84
Using a URLConnection ........................................................................ 86
Sending Email Through a URLConnection .......................................... 87
Connecting to a Web Server ................................................................. 89
A Simple Web Server ............................................................................ 91
A Proxy Server ...................................................................................... 93
Networking with Applets ..................................................................... 96
A Generic Client .................................................................................... 99
vi
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A Generic Multithreaded Server ......................................................... 101
A Multithr eaded Pr oxy Server ............................................................ 113
Sending Datagrams ............................................................................. 116
Receiving Datagrams .......................................................................... 117
Exercises .............................................................................................. 119
Chapter 6—Secur ity and Cryptog raphy ....................................... 121
Running Untrusted Code .................................................................... 122
Loading Untrusted Code ..................................................................... 123
Message Digests and Digital Signatures ............................................ 128
Cryptography ...................................................................................... 136
Exercises .............................................................................................. 139
Chapter 7—Inter nationalization ..................................................... 141
A Word About Locales ........................................................................ 141
Unicode ............................................................................................... 142
Character Encodings ........................................................................... 146
Handling Local Customs ..................................................................... 148
Localizing User-Visible Messages ....................................................... 151
For matted Messages ............................................................................ 156
Exercises .............................................................................................. 159
Chapter 8—Reflection ............................................................................... 161
Obtaining Class and Member Information ........................................ 161
Invoking a Named Method ................................................................ 164
Exercises .............................................................................................. 168
Chapter 9—Object Serialization ........................................................ 169
Simple Serialization ............................................................................. 169
Custom Serialization ........................................................................... 172
Exter nalizable Classes ......................................................................... 174
Serialization and Class Versioning ...................................................... 176
Serialized Applets ................................................................................ 177
Exercises .............................................................................................. 178
vii
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Part II: Graphics and GUIs
Chapter 10—Graphical User Interfaces ....................................... 181
Components ........................................................................................ 183
Containers ........................................................................................... 189
Layout Management ............................................................................ 190
Event Handling ................................................................................... 203
A Complete GUI ................................................................................. 217
Actions and Reflection ........................................................................ 221
Custom Dialogs ................................................................................... 222
Displaying Tables ................................................................................ 227
Displaying Trees ................................................................................. 230
A Simple Web Browser ....................................................................... 234
Describing GUIs with Properties ....................................................... 242
Themes and the Metal Look-and-Feel ............................................... 253
Custom Components .......................................................................... 257
Exercises .............................................................................................. 263
Chapter 11—Graphics .............................................................................. 266
Graphics Before Java 1.2 .................................................................... 267
The Java 2D API .................................................................................. 276
Drawing and Filling Shapes ............................................................... 277
Transfor ms ........................................................................................... 279
Line Styles with BasicStroke ............................................................... 281
Str oking Lines ...................................................................................... 283
Filling Shapes with Paint .................................................................... 284
Antialiasing .......................................................................................... 287
Combining Colors with AlphaComposite .......................................... 289
Image Processing ................................................................................ 292
A Custom Shape .................................................................................. 295
Custom Strokes ................................................................................... 299
Custom Paint ....................................................................................... 303
Advanced Animation .......................................................................... 305
Displaying Graphics Examples .......................................................... 308
Exercises .............................................................................................. 312
viii
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