tomcat下用Log4j 按文件大小，生成catalina.out日志文件
一、下载所需类包 （可在http://download.csdn.net/detail/function413/4977751中下载tomcat log4j.rar 里面包含以下JAR包）
1、下载log4j下载1.2以后的版本
下载地址：http://logging.apache.org/log4j/1.2/download.html
2、下载tomcat-juli.jar，tomcat-juli-adapters.jar
使用LOG4J来接管tomcat6.0.18的日志文件必须要下载两个文件：tomcat-juli.jar，tomcat-juli-adapters.jar。
下载地址为：http://www.apache.org/dist/tomcat/tomcat-6/v6.0.18/bin/extras/ (如果tomcat为其他版本，请下载对应版本的类包)
二、修改相关配置文件
1、修改${catalina.home}/conf/context.xml
修改：
2、复制log4j.jar到${catalina.home}/lib下
3、复制tomcat-juli-adapters.jar到${catalina.home}/lib下
4、复制tomcat-juli.jar到${catalina.home}/bin下，在该目录会存在该文件，覆盖 即可
5、建立log4j.properties,并把其放到${catalina.home}/lib下
Log4j.properties的内容如 下：相关参数根据需要可以相应修改
log4j.rootLogger=INFO, CATALINA
# Define all the appenders
log4j.appender.CATALINA=org.apache.log4j.RollingFileAppender
log4j.appender.CATALINA.File=${catalina.base}/logs/nova.log
log4j.appender.CATALINA.MaxFileSize=10240KB
log4j.appender.CATALINA.MaxBackupIndex=100
log4j.appender.CATALINA.Append=true
log4j.appender.CATALINA.Encoding=GBK
# Roll-over the log once per day
#log4j.appender.CATALINA.DatePattern='.'yyyy-MM-dd-HH-mm'.log'
log4j.appender.CATALINA.layout = org.apache.log4j.PatternLayout
log4j.appender.CATALINA.layout.ConversionPattern = %d [%t] %-5p %c- %m%n
log4j.appender.LOCALHOST=org.apache.log4j.DailyRollingFileAppender
log4j.appender.LOCALHOST.File=${catalina.base}/logs/novalocalhost.log
log4j.appender.LOCALHOST.Append=true
log4j.appender.LOCALHOST.Encoding=GBK
log4j.appender.LOCALHOST.DatePattern='.'yyyy-MM-dd'.log'
log4j.appender.LOCALHOST.layout = org.apache.log4j.PatternLayout
log4j.appender.LOCALHOST.layout.ConversionPattern = %d [%t] %-5p %c- %m%n
log4j.appender.MANAGER=org.apache.log4j.DailyRollingFileAppender
log4j.appender.MANAGER.File=${catalina.base}/logs/novamanager.log
log4j.appender.MANAGER.Append=true
log4j.appender.MANAGER.Encoding=GBK
log4j.appender.MANAGER.DatePattern='.'yyyy-MM-dd'.log'
log4j.appender.MANAGER.layout = org.apache.log4j.PatternLayout
log4j.appender.MANAGER.layout.ConversionPattern = %d [%t] %-5p %c- %m%n
log4j.appender.HOST-MANAGER=org.apache.log4j.DailyRollingFileAppender
log4j.appender.HOST-MANAGER.File=${catalina.base}/logs/novahost-manager.log
log4j.appender.HOST-MANAGER.Append=true
log4j.appender.HOST-MANAGER.Encoding=GBK
log4j.appender.HOST-MANAGER.DatePattern='.'yyyy-MM-dd'.log'
log4j.appender.HOST-MANAGER.layout = org.apache.log4j.PatternLayout
log4j.appender.HOST-MANAGER.layout.ConversionPattern = %d [%t] %-5p %c- %m%n
log4j.appender.CONSOLE=org.apache.log4j.ConsoleAppender
log4j.appender.CONSOLE.Encoding=GBK
log4j.appender.CONSOLE.layout = org.apache.log4j.PatternLayout
log4j.appender.CONSOLE.layout.ConversionPattern = %d [%t] %-5p %c- %m%n
# Configure which loggers log to which appenders
log4j.logger.org.apache.catalina.core.ContainerBase.[Catalina].[localhost]=INFO, LOCALHOST
log4j.logger.org.apache.catalina.core.ContainerBase.[Catalina].[localhost].[/manager]=\
INFO, MANAGER
log4j.logger.org.apache.catalina.core.ContainerBase.[Catalina].[localhost].[/host-manager]=\
INFO, HOST-MANAGER