1、加入日志属性文件
log4j.properties
log4j.rootLogger=DEBUG,Console,fileout
log4j.appender.Console=org.apache.log4j.ConsoleAppender
log4j.appender.Console.layout=org.apache.log4j.PatternLayout
log4j.appender.Console.layout.ConversionPattern=%5p [%c] %m%n
log4j.appender.fileout=org.apache.log4j.RollingFileAppender #表示需要输出的文件，有些日志在控制台不会输出，会在
log4j.appender.fileout.File=ibatis.log
log4j.appender.fileout.MaxFileSize=10000KB
log4j.appender.fileout.layout=org.apache.log4j.PatternLayout
log4j.appender.fileout.layout.ConversionPattern=%5p [%c] %m%n
2、
有时候系统找不到日志属性文件，这里加上路径指定下
package com.mycompany.app; import java.io.IOException; import org.apache.log4j.Logger;
import org.apache.log4j.PropertyConfigurator; public class Copy_2_of_App { public static void main(String[] args) throws IOException {
PropertyConfigurator.configure("D:/test_8_25/my-app/src/main/java/log4j.properties");
Logger LOG = Logger.getLogger(Copy_2_of_App.class);
LOG.info("test"); System.out.print("ok");
} }
3、log4j的配置，在wire.log里面打印http请求的数据
log4j.rootLogger=INFO log4j.appender.stdout=org.apache.log4j.ConsoleAppender log4j.appender.stdout.layout=org.apache.log4j.PatternLayout log4j.appender.stdout.layout.ConversionPattern=%5p [%c] %m%n log4j.appender.F=org.apache.log4j.FileAppender log4j.appender.F.File=wire.log log4j.appender.F.layout=org.apache.log4j.PatternLayout log4j.appender.F.layout.ConversionPattern =%5p [%c] %m%n log4j.logger.httpclient.wire=DEBUG, F log4j.logger.org.apache.commons.httpclient=DEBUG, stdout