### set log levels ###
log4j.rootLogger= INFO, Console, File, Error
### Console appender definition ###
log4j.appender.Console=org.apache.log4j.ConsoleAppender
log4j.appender.Console.Target=System.out
log4j.appender.Console.layout=org.apache.log4j.PatternLayout
log4j.appender.Console.layout.ConversionPattern=%d %p [%c] %m%n
###### File appender definition #######
log4j.appender.File = org.apache.log4j.DailyRollingFileAppender
log4j.appender.File.File = ${catalina.home}/logs/projectName/log.log
log4j.appender.File.Append = true
log4j.appender.File.Threshold = INFO
log4j.appender.File.layout = org.apache.log4j.PatternLayout
log4j.appender.File.layout.ConversionPattern=%d %p [%c] %m%n
###### Error appender definition #######
log4j.appender.Error = org.apache.log4j.DailyRollingFileAppender
log4j.appender.Error.File = ${catalina.home}/logs/projectName/error.log
log4j.appender.Error.Append = true
log4j.appender.Error.Threshold = ERROR
log4j.appender.Error.layout = org.apache.log4j.PatternLayout
log4j.appender.Error.layout.ConversionPattern = %d %p [%c] %m%n
原文：http://my.oschina.net/u/1469821/blog/349507