log4j.properties文件: log4j.rootLogger=warn, console, filelog4j.logger.mylog=info#console configlog4j.appender.console=org.apache.log4j.ConsoleAppenderlog4j.appender.console.layout=org.apache.log4j.PatternLayout#file configlog4j.appender.file = org.apache.log4j.RollingFileAppender log4j.appender.file.File =c:/logs.loglog4j.appender.file.layout=org.apache.log4j.PatternLayout 测试代码: package log4j;import org.apache.log4j.Logger;import org.apache.log4j.PropertyConfigurator;public class Log4jDemo ...{ public static void main(String[] args) ...{ String path = "D:/eclipse/workspace/Java/src/log4j/log4j.properties"; PropertyConfigurator.configure(path); /**//* * 下面注释的代码是把properties文件里面的信息和这个Log4jDemo类关联起来,当然, * 如果我们设计的是一个web程序,就可以把properties文件在web-config.XML文件里面配置。 */// PropertyConfigurator.configure(Log4jDemo.class.getResource("log4j.properties")); Logger logger = Logger.getLogger("mylog"); logger.info("this is log4j!"); }}