How to do the initial setup of my logging framework
如何设置我的日志框架？
原文来自于http://log4e.jayefem.de/index.php/Log4E:FAQ
If you are already familiar with your logging framework you might want to skip this section.
This chapter gives you a slight idea of how to make the initial setup of your logger. This is NOT supported by Log4E at the moment and was not the intended use at the beginning of this project.
Log4E does not ship any logging framework which means that you have to download and install it for yourself!
Examples are available for Log4j, Commons Logging, JDK 1.4 Logging (again: you have to do this for yourself).
1. Download Log4j at http://logging.apache.org/ and copy the log4j.jar to your lib directory.
2. Create a new file 'log4j.properties' or 'log4j.xml' (case sensitive) and put it in your classpath. To be more concrete: Put in your source directory, the file will be copied by Eclipse automatically to your build directory.
For example:
.../MyEclipseProject/
.../MyEclipseProject/src/log4j.properties
.../MyEclipseProject/src/com/mycompany/myapp/...
2a. Alternatively, you can use the method org.apache.log4j.PropertyConfigurator.configure("..../log4j.properties");
3. Edit the 'log4j.properties' to declare your own categories, log levels and appenders (which means the output like standard out or a log file).
log4j.properties example:
#######################################################################
# Categories and levels
#######################################################################
log4j.rootCategory=ERROR, FileApp, ConApp
log4j.category.de.jayefem=DEBUG
#######################################################################
# Appenders
#######################################################################
# ConApp is set to be a ConsoleAppender.
log4j.appender.ConApp=org.apache.log4j.ConsoleAppender
# ConApp uses PatternLayout.
log4j.appender.ConApp.layout=org.apache.log4j.PatternLayout
# Define Pattern
log4j.appender.ConApp.layout.ConversionPattern=%d [%t] %-5p %c - %m%n
# FileApp
log4j.appender.FileApp=org.apache.log4j.RollingFileAppender
log4j.appender.FileApp.File=D:/proj/Devel/Java/de.jayefem.log4e/log/log4e.log
log4j.appender.FileApp.MaxFileSize=500KB
# Keep one backup file
log4j.appender.FileApp.MaxBackupIndex=1
log4j.appender.FileApp.layout=org.apache.log4j.PatternLayout
log4j.appender.FileApp.layout.ConversionPattern=%d [%t] %-5p %c - %m%n
"de.jayefem", "ConApp", "FileApp" and the path to the logfile are selfdefined. All other words are keywords of Log4j.
4. That's all. Have fun.
Note that there are much more possibilities to configure Log4j. Check http://logging.apache.org/ for more.
Jakarta Commons Logging Framework is a wrapper for all common logging frameworks. If you want to use it, you have to install it AND the underlying logging framework. To install the Commons Logging download it from http://jakarta.apache.org/commons/logging/ and put the commons-logging.jar in your lib directory.
The Commons Logging Frameworks uses Log4j by default. When Log4j isn't found in classpath and JDK 1.4 or higher is being used, the JDK 1.4 logger will be used. If none of the above applies, Commons Logging will fall back to the internal SimpleLog.
It is also possible to specify the logging framework directly:
1. Create a new file 'commons-logging.properties' and put it in your classpath. To be more concrete: Put it in your source directory, the file will be copied by Eclipse automatically to your build directory.
For example:
.../MyEclipseProject/
.../MyEclipseProject/src/commons-logging.properties
.../MyEclipseProject/src/com/mycompany/myapp/...
2. Edit the 'commons-logging.properties'.
commons-logging.properties example:
#
#org.apache.commons.logging.LogFactory=org.apache.commons.logging.impl.LogFactoryImpl
# SimpleLog
#org.apache.commons.logging.Log = org.apache.commons.logging.impl.SimpleLog
# JDK 1.4 logger
#org.apache.commons.logging.Log=org.apache.commons.logging.impl.Jdk14Logger
# Avalon Toolkit
#org.apache.commons.logging.Log=org.apache.commons.logging.impl.LogKitLogger
# Log4j
org.apache.commons.logging.Log=org.apache.commons.logging.impl.Log4JLogger
As though it is not recommended to use Simplelog because it is not threadsafe, here's an example how to set it up:
1. Create a new file 'simplelog.properties' and put it in your classpath. To be more concrete: Put it in your source directory, the file will be copied by Eclipse automatically to your build directory.
For example:
.../MyEclipseProject/
.../MyEclipseProject/src/simplelog.properties
.../MyEclipseProject/src/com/mycompany/myapp/...
2. Edit the 'simplelog.properties' to declare your own categories and log levels.
simplelog.properties example:
# Default logging detail level for all instances of SimpleLog. Must be one of
# ("trace", "debug", "info", "warn", "error", or "fatal"). If not specified,
# defaults to "info".
org.apache.commons.logging.simplelog.defaultlog=warn
# Logging detail level for a SimpleLog instance named "xxxxx". Must be one of
# ("trace", "debug", "info", "warn", "error", or "fatal"). If not specified, the
# default logging detail level is used.
org.apache.commons.logging.simplelog.log.de.jayefem.log4e=debug
# Set to true if you want the Log instance name to be included in output
# messages. Defaults to false.
org.apache.commons.logging.simplelog.showlogname=false
# Set to true if you want the last componet of the name to be included in
# output messages. Defaults to true.
org.apache.commons.logging.simplelog.showShortLogname=true
# Set to true if you want the current date and time to be included in output
# messages. Default is false.
org.apache.commons.logging.simplelog.showdatetime=true
See http://jakarta.apache.org/commons/logging/ for more.
# handlers
handlers=java.util.logging.FileHandler, java.util.logging.ConsoleHandler
# general level
.level=INFO
# file handler
java.util.logging.FileHandler.pattern = %h/java%u.log
java.util.logging.FileHandler.limit = 50000
java.util.logging.FileHandler.count = 1
java.util.logging.FileHandler.formatter = java.util.logging.XMLFormatter
# console handler
java.util.logging.ConsoleHandler.level = FINEST
java.util.logging.ConsoleHandler.formatter = java.util.logging.SimpleFormatter
test.de.jayefem.log4e.logkits.JDK1_4_Logging.level = FINEST
Since I am not an expert of JDK 1.4 logging there might be better ways to configure the logging framework. Suggestions are welcome.
See http://java.sun.com/j2se/1.4.2/docs/api/java/util/logging/package-summary.html for more information.
据说apache Jakarta小组曾经强烈建议sun把log4j作为jdk1.4的日志工具，但这条建议没有被采纳。于是他们就开发了common logging 来兼容log4j和jdk的logging，呵呵。简单一点，还是使用log4j吧。
note：在eclipse中运行程序时似乎并不会搜索本机的classpath，因此即使把log4j.properties文件放到classpath中也没用。
最近发现Weblogic也是用的log4j，呵呵。