1. http://hehongwei44.iteye.com/blog/1494999
2. http://maymay.iteye.com/blog/1275432
#log4j.rootLogger = [ level ] , appenderName, appenderName, ...
log4j.rootLogger = info,console, R
#level=INFO,all can be output
#console is set to be a ConsoleAppender
log4j.appender.console = org.apache.log4j.ConsoleAppender
#console have four patterns
#org.apache.log4j.HTMLLayout
#org.apache.log4j.PatternLayout
#org.apache.log4j.SimpleLayout
#org.apache.log4j.TTCCLayout
log4j.appender.console.layout = org.apache.log4j.PatternLayout
#define the output type
log4j.appender.console.layout.ConversionPattern = %-d{yyyy-MM-dd HH:mm:ss} [%c]-[%p] %m%n
#file is set to output to a extra file
log4j.appender.R = org.apache.log4j.RollingFileAppender
#the absolute route of the log4j file
log4j.appender.R.File =${catalina.home}/logs/lego.log
#the size
log4j.appender.R.MaxFileSize = 500KB
#back up a file
log4j.appender.R.MaxBackupIndex = 1
log4j.appender.R.layout = org.apache.log4j.PatternLayout
log4j.appender.R.layout.ConversionPattern=%-d{yyyy-MM-dd HH:mm:ss} [%c]-[%p] - %m%n
log4j.logger.com.sc.ops.be.lego.service = info,legoService
log4j.appender.legoService = org.apache.log4j.DailyRollingFileAppender
log4j.appender.legoService.File =${catalina.home}/logs/lego_build.log
log4j.appender.legoService.layout = org.apache.log4j.PatternLayout
log4j.appender.legoService.layout.ConversionPattern=%-d{yyyy-MM-dd HH:mm:ss.SSS} [%p] - %m%n