JAVA使用log4j

#不+All，只写后一种LOG
log4j.rootLogger =ALL,systemOut,logRollingFile 

#输出到控制台 
log4j.appender.systemOut = org.apache.log4j.ConsoleAppender 
log4j.appender.systemOut.layout = org.apache.log4j.PatternLayout 
#"%-5p"：消息类型（DEBUG？INFO？），左对其，5字符
#"%l"：那个文件那个方法哪一行输出log
#"%n"：换行
#"%m"：log消息
log4j.appender.systemOut.layout.ConversionPattern = [%-5p][%-22d{yyyy/MM/dd HH:mm:ss.SSS}][%l]%n%m%n
#阈值（log级别：DEBUG，INFO，ERROR，WARN）
log4j.appender.systemOut.Threshold = DEBUG

#设定文件大小输出到文件 
log4j.appender.logRollingFile = org.apache.log4j.RollingFileAppender 
log4j.appender.logRollingFile.layout = org.apache.log4j.PatternLayout 
log4j.appender.logRollingFile.layout.ConversionPattern = %m%n
log4j.appender.logRollingFile.Threshold = DEBUG 
log4j.appender.logRollingFile.File = C:/log/AhLog.txt 
log4j.appender.logRollingFile.MaxFileSize = 1MB 
log4j.appender.logRollingFile.MaxBackupIndex = 10

import org.apache.log4j.Logger;

public class TestLog4j {
    static Logger log = Logger.getLogger(TestLog4j.class.getName());

    public static void main(String[] args) {
        log.debug("AH DEBUG");
        log.info("AH INFO");
        log.error("AH ERROR");
        log.warn("AH WARN");
    }
}