Log4j的使用

1.引入jar包

将log4j-1.2.17.jar引入到工程中。

2.配置文件log4j.properties

### \u8BBE\u7F6E###
log4j.rootLogger = debug,stdout,D,E

### \u8F93\u51FA\u4FE1\u606F\u5230\u63A7\u5236\u62AC ###
log4j.appender.stdout = org.apache.log4j.ConsoleAppender
log4j.appender.stdout.Target = System.out
log4j.appender.stdout.layout = org.apache.log4j.PatternLayout
log4j.appender.stdout.layout.ConversionPattern = [%-5p] %d{yyyy-MM-dd HH:mm:ss,SSS} method:%l%n%m%n

### \u8F93\u51FADEBUG \u7EA7\u522B\u4EE5\u4E0A\u7684\u65E5\u5FD7\u5230=E://logs/error.log ###
log4j.appender.D = org.apache.log4j.DailyRollingFileAppender
log4j.appender.D.File = ./logs/log.log
log4j.appender.D.Append = true
log4j.appender.D.Threshold = DEBUG 
log4j.appender.D.layout = org.apache.log4j.PatternLayout
log4j.appender.D.layout.ConversionPattern = %-d{yyyy-MM-dd HH:mm:ss}  [ %t:%r ] - [ %p ]  %m%n

### \u8F93\u51FAERROR \u7EA7\u522B\u4EE5\u4E0A\u7684\u65E5\u5FD7\u5230=E://logs/error.log ###
log4j.appender.E = org.apache.log4j.DailyRollingFileAppender
log4j.appender.E.File =./logs/error.log 
log4j.appender.E.Append = true
log4j.appender.E.Threshold = ERROR 
log4j.appender.E.layout = org.apache.log4j.PatternLayout
log4j.appender.E.layout.ConversionPattern = %-d{yyyy-MM-dd HH:mm:ss}  [ %t:%r ] - [ %p ]  %m%n

3.编写代码

package com.java.logdemo;

import org.apache.log4j.Logger;
import org.junit.Before;
import org.junit.Test;

public class Log4jTest {
    private static Logger logger ;
    
    @Before
    public void bedore(){
        logger = Logger.getLogger(Log4jTest.class);
    }
    @Test
    public void test(){
        // 记录debug级别的信息
        logger.debug("This is debug message.");
        // 记录info级别的信息
        logger.info("This is info message.");
        // 记录error级别的信息
        logger.error("This is error message.");
    }
}

4.参考

最详细的Log4j使用教程