如何使log4j也写入控制台

Question

有没有办法告诉log4j将其日志写入文件和控制台？谢谢有我的属性:

log4j.rootLogger=DEBUG,console,R
log4j.rootLogger=INFO, FILE

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{yyyy-MM-dd HH:mm:ss,SSS} %-5p - %m%n

log4j.appender.FILE=org.apache.log4j.RollingFileAppender
log4j.appender.FILE.File=log4j.log
log4j.appender.FILE.MaxFileSize=512KB
log4j.appender.FILE.MaxBackupIndex=3
log4j.appender.FILE.layout=org.apache.log4j.PatternLayout
log4j.appender.FILE.layout.conversionPattern=%d{yyyy-MM-dd HH:mm:ss,SSS} %-5p - %m%n

Answer 1

您的根记录器定义有点混乱.请参阅log4j文档.

这是标准的Java属性文件,这意味着将行视为键=值对.你的第二log4j.rootLogger行是覆盖第一行,这就解释了为什么你没有在consoleappender 上看到任何东西.

您需要将两个rootLogger定义合并为一个.看起来您正在尝试将DEBUG消息发送到控制台并将INFO消息发送到该文件.根记录器只能有一个级别,因此您需要更改配置,以便appender具有适当的级别.

虽然我没有证实这是正确的,但我猜它看起来像这样:

log4j.rootLogger=DEBUG,console,file
log4j.appender.console=org.apache.log4j.ConsoleAppender
log4j.appender.file=org.apache.log4j.RollingFileAppender

请注意,套管中也有错误 - 您在一个地方有控制台小写,在另一个地方有CAPS.

Answer 2

你的log4j文件应该看起来像下面的阅读评论.

# Define the types of logger and level of logging    
log4j.rootLogger = DEBUG,console, FILE

# Define the File appender    
log4j.appender.FILE=org.apache.log4j.FileAppender    

# Define Console Appender    
log4j.appender.console=org.apache.log4j.ConsoleAppender    

# Define the layout for console appender. If you do not 
# define it, you will get an error    
log4j.appender.console.layout=org.apache.log4j.PatternLayout

# Set the name of the file    
log4j.appender.FILE.File=log.out

# Set the immediate flush to true (default)    
log4j.appender.FILE.ImmediateFlush=true

# Set the threshold to debug mode    
log4j.appender.FILE.Threshold=debug

# Set the append to false, overwrite    
log4j.appender.FILE.Append=false

# Define the layout for file appender    
log4j.appender.FILE.layout=org.apache.log4j.PatternLayout    
log4j.appender.FILE.layout.conversionPattern=%m%n

Answer 3

这适用于调试模式下的控制台

log4j.appender.console=org.apache.log4j.ConsoleAppender
log4j.appender.console.Threshold=DEBUG
log4j.appender.console.Target=System.out
log4j.appender.console.layout=org.apache.log4j.PatternLayout
log4j.appender.console.layout.conversionPattern=%d{yyyy-MM-dd HH:mm:ss,SSS} %-5p - %m%n