JDK 1.4 Tutorial

408 Pages·2012·10.137 MB·English

by  G. Travis

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JDK 1.4 Tutorial
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JDK 1.4 Tutorial
GREG M. TRAVIS
MANNING
Greenwich
(74° w. long.)
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Library of Congress Cataloging-in-Publication Data
Travis, Greg
Book Title /Bill J. Author.
p. cm.
Includes bibliographical references and index.
ISBN ?-??????-??-? (alk. paper)
1. Java (Computer program language). 2. Title.
????????????? 1998
?????????—???? ??-?????
CIP
Manning Publications Co. Copyeditor: Andy Carroll
209 Bruce Park Avenue Typesetter: Tony Roberts
Greenwich, CT 06830 Cover designer: Leslie Haimes
ISBN 1-930110-66-9
Printed in the United States of America
1 2 3 4 5 6 7 8 9 10 – VHG – 05 04 03 02
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To Susan
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contents
preface xv
acknowledgments xvii
about this book xix
author online xxvii
about the cover illustration xxix
1 Basic NIO (New Input/Output) 1
1.1 Doing I/O with channels and buffers 2
Getting a channel from a stream 3 (cid:1) Creating a buffer
revision 4 (cid:1) Reading from a channel 4 (cid:1) Writing to a
channel 5 (cid:1) Reading and writing together 6
1.2 Understanding buffers 7
Creating buffers 7 (cid:1) get() and put() 7 (cid:1) Buffer state values 9
flip() and clear() 10 (cid:1) slice() and subbuffers 12 (cid:1) Buffers of
other types 13 (cid:1) Reading and writing other types from a
ByteBuffer 14 (cid:1) Direct buffers 16 (cid:1) Example: TCP/IP
forwarding 17 (cid:1) Doing I/O with channels and buffers 27
1.3 The File Locking facility 28
Types of locks 28 (cid:1) Using locks 29 (cid:1) Acquiring locks 30
Portability issues 31 (cid:1) Example: a simple database 32
1.4 Summary 36
vii
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viii CONTENTS
2 Advanced NIO (New Input/Output) 37
2.1 Reading and writing with MappedByteBuffers 38
Advantages of MappedByteBuffers 38 (cid:1) Disadvantages of
MappedByteBuffers 40 (cid:1) Using MappedByteBuffers 40
Example: checksumming 41
2.2 Nonblocking I/O 42
The multithreaded approach 43 (cid:1) The really bad single-
threaded approach 44 (cid:1) Polling 44 (cid:1) Example: a polling chat
server 46 (cid:1) Multiplexing with select() 49
2.3 Encoding and decoding with Charsets 58
Decoding and encoding 59 (cid:1) Finding available Charsets 59
Using encoders and decoders 61
2.4 Network interfaces 63
When to use a network interface 64 (cid:1) Getting a list of
NetworkInterfaces 64 (cid:1) Reporting on NetworkInterfaces 64
Getting a list of InetAddresses 66 (cid:1) Getting a
NetworkInterface by InetAddress 66 (cid:1) Getting a
NetworkInterface by name 67 (cid:1) Listening on a
particular address 67
2.5 Summary 73
3 Java2D 75
3.1 The Print Service API 76
Print Service packages 76 (cid:1) Document flavors 77 (cid:1) Printer
discovery 77 (cid:1) Printer attributes 79 (cid:1) The SimpleDoc class 80
The DocPrintJob interface 81 (cid:1) Example: printing an
image 81 (cid:1) Example: a custom print dialog box 83
3.2 Reading and writing images with the Image I/O API 88
The plug-in model 89 (cid:1) Simple reading 89 (cid:1) Simple
writing 90 (cid:1) The ImageIO class 90 (cid:1) Discovering available
formats 90 (cid:1) Example: reading and displaying an image 92
Example: writing an image 92 (cid:1) The ImageReader class 93
The ImageWriter class 95 (cid:1) Customizing the reading
process 97 (cid:1) Listeners 99 (cid:1) Example: generating a graph 102
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CONTENTS ix
3.3 Summary 105
4 Java Web Start (JAWS) 107
4.1 Understanding the JAWS execution model 108
Client, server, and application 109 (cid:1) The sandbox 110
Consider the possibilities 110
4.2 Building and deploying a JAWS application 111
JAR files 111 (cid:1) The JNLP file 111
Configuring the web server 113
4.3 Using the sandbox: services 113
Using the sandbox: resources 114
4.4 Bypassing the sandbox 115
4.5 Example: a simple drawing program 117
PicoDraw.java 118 (cid:1) DrawCanvas.java 131
TransferableImage.java 135
4.6 Summary 136
5 Logging 137
5.1 Logging overview 138
Log message format 139 (cid:1) Logging levels 139 (cid:1) Logger
names and the logger hierarchy 140 (cid:1) Logging methods 141
The LogRecord class 141 (cid:1) Handlers 142 (cid:1) Filters 143
Formatters 143 (cid:1) Logging efficiency 144
The philosophy of logging 144
5.2 Configuring the Logging system 145
Configuring handlers 145 (cid:1) Configuration values for
standard handlers 146 (cid:1) Configuring loggers 148
Global handlers 149
5.3 Using logging in a program 149
5.4 Writing a custom handler 155
5.5 Writing a custom formatter 165
5.6 Summary 168
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x CONTENTS
6 Assertion facility 171
6.1 Assertion basics 172
Why use assertions? 172 (cid:1) Assertions vs. other error code 173
Designing by contract 174
6.2 Working with assertions 174
Assertion syntax 175 (cid:1) Compiling with assertions 177
Controlling assertions from the command line 178
Controlling assertions programmatically 181 (cid:1) Removing
assertions completely 182 (cid:1) Determining if assertions are
enabled 183 (cid:1) Catching an assertion failure 184
Assertions and class initialization 185
6.3 Assertion examples 187
Avoiding inconsistent states 187 (cid:1) Narrowing the range
of states 189 (cid:1) Ensuring consistency between container
objects and contained objects 189 (cid:1) More complicated
consistency checks 192
6.4 Knowing when to use assertions 193
Rules of use 193 (cid:1) What to check for 197
Miscellaneous rules 202
6.5 Summary 204
7 Exceptions 205
7.1 Chained exceptions 206
7.2 StackTraceElements 208
What is a stack trace? 208 (cid:1) Using StackTraceElements 210
Writing a custom stack trace dumper 210
Synthesizing a stack trace 215
7.3 Summary 228