Pro Apache Log4j, Second Edition

Contents......Page 6
About the Author......Page 12
About the Technical Reviewer......Page 13
Acknowledgments......Page 14
Introduction......Page 15
What Is Logging?......Page 17
Logging Information Represents the Application State......Page 18
Disadvantages of Logging......Page 19
How Logging Works......Page 20
Evaluating a Logging Package......Page 21
Commons Logging API......Page 22
The Road Ahead......Page 23
Installing log4j......Page 24
Overview of the log4j Architecture......Page 25
Naming and Placing the Configuration File......Page 27
What We Can Configure......Page 28
XML-Style Configuration......Page 30
Initialization Through VM Parameters......Page 31
Creating a Log4j Configuration File......Page 32
Why the Message Printed Twice......Page 33
Dynamic Loading of Configuration......Page 34
Setting Up Tomcat......Page 35
An Example Servlet......Page 37
Level Object......Page 38
Logger Object......Page 39
How to Obtain a Logger......Page 40
Logging Information......Page 41
Conditions of Successful Logging......Page 43
A Logger Example......Page 44
LogManager Object......Page 46
Message Diagnostic Context (MDC)......Page 47
Conclusion......Page 49
CHAPTER 3 Destination of Logging—The Appender Objects......Page 50
Properties of Appender......Page 51
Adding Appenders to Loggers......Page 52
WriterAppender......Page 53
Properties of WriterAppender......Page 54
A ConsoleAppender Example......Page 55
Properties of FileAppender......Page 56
Sample Configuration of FileAppender......Page 57
Properties of RollingFileAppender......Page 58
Useful Operations in RollingFileAppender......Page 59
Sample Configuration of RollingFileAppender......Page 60
Rolling the File Daily—DailyRollingFileAppender......Page 61
A File-Based Logging Example......Page 63
Logging Asynchronously—AsyncAppender......Page 66
Sample Use of AsyncAppender......Page 67
Logging to a Database with JDBCAppender......Page 68
Configuring JDBCAppender......Page 69
Sample Configuration for JDBCAppender......Page 70
What Is JMS?......Page 72
JMS and log4j......Page 73
Working with SocketAppender......Page 75
Configuring SocketAppender......Page 76
Logging to Windows NT Event Log with NTEventLogAppender......Page 77
E-mail the Logging Message—SMTPAppender......Page 78
The Scenario......Page 80
A JMSAppender Example......Page 82
A SocketAppender Example......Page 86
Final Words......Page 89
Conclusion......Page 90
The Layout Hierarchy......Page 91
The Layout Objects in log4j......Page 92
Keeping It Simple—SimpleLayout......Page 93
The Mandatory Information......Page 94
Configuring TTCCLayout Programmatically......Page 95
Configuring TTCCLayout via Configuration File......Page 97
HTMLLayout......Page 99
XMLLayout......Page 104
Give It a Pattern—PatternLayout......Page 106
Conclusion......Page 108
Filtering Explained......Page 109
Level-Based Filtering......Page 110
Using LevelRangeFilter......Page 111
A Custom Level-Based Filter—SelectedLevelFilter......Page 113
Filter Chaining......Page 116
Error Handling......Page 117
Writing a Custom ErrorHandler......Page 120
Configuring ErrorHandler......Page 122
A Custom Renderer Example......Page 123
Configuring ObjectRenderer......Page 126
Renderer in Action......Page 127
Conclusion......Page 128
Creating the Custom WindowAppender......Page 129
The Custom WindowAppender Architecture......Page 130
Implementing the Custom WindowAppender......Page 131
Testing the Custom WindowAppender......Page 134
Configuring log4j from a Database......Page 136
Reading Configuration Information from the Database via the Configuration Loader......Page 137
Writing the Configuration Class......Page 144
A Database-Based Configuration Example......Page 147
Creating a Custom Level Class......Page 149
Generating a Custom Logger Factory Object......Page 151
Using Custom Logging Components......Page 152
A Simpler Approach to Using a Custom Level Class......Page 154
Writing a Custom Layout......Page 158
Conclusion......Page 161
CHAPTER 7 A Complete log4j Example......Page 162
Conclusion......Page 168
Why Logging Is Difficult in J2EE......Page 169
WebLogic Class Loaders Explained......Page 170
Case 2......Page 171
Making Log4j Work in J2EE......Page 172
Conclusion......Page 173
What Is a Tag?......Page 174
A Simple Example of Using the Log Tag Library......Page 175
Configuration File for the Log Tag Library......Page 176
Setting the Environment......Page 177
Using a Custom Logger with the Log Tag Library......Page 178
Description of Log Tags......Page 179
Creating a New Tag......Page 181
The Custom TraceTag in Action......Page 183
Conclusion......Page 184
Obtaining a Logger......Page 185
Using Logger Hierarchy......Page 186
Logging Messages Efficiently......Page 187
Formatting Logging Information......Page 189
Using Filter Objects......Page 190
Configuration Issues......Page 191
Comparing log4j and the JDK Logging API......Page 192
Formatting Logging Information: Comparing Formatter and Layout Objects......Page 193
Comparing Error Handling......Page 194
Plug-ins......Page 195
Conclusion......Page 196
APPENDIX A. The log4j Configuration Parameters......Page 197
APPENDIX B. The log4j DTD......Page 200
A......Page 204
D......Page 205
H......Page 206
L......Page 207
M......Page 208
S......Page 209
W......Page 210
X......Page 211