一、简介

Loggers组件在此系统中被分为五个级别：DEBUG、INFO、WARN、ERROR和FATAL。这五个级别是有顺序的，DEBUG < INFO < WARN < ERROR < FATAL，分别用来指定这条日志信息的重要程度，明白这一点很重要，Log4j有一个规则：只输出级别不低于设定级别的日志信息，假设Loggers级别设定为INFO，则INFO、WARN、ERROR和FATAL级别的日志信息都会输出，而级别比INFO低的DEBUG则不会输出

二、log4j.properties文件配置

log4j.rootLogger=DEBUG, stdout, logfile

log4j.category.org.springframework=ERROR
#log4j.category.org.apache=INFO
#log4j.category.org.apache=DEBUG

log4j.appender.stdout=org.apache.log4j.ConsoleAppender
log4j.appender.stdout.layout=org.apache.log4j.PatternLayout
log4j.appender.stdout.layout.ConversionPattern=%d %p [%c] - %m%n

log4j.appender.logfile=org.apache.log4j.RollingFileAppender
log4j.appender.logfile.File=${base.logs.dir}/WEB-INF/log/myweb.log
log4j.appender.logfile.MaxFileSize=512KB
log4j.appender.logfile.MaxBackupIndex=5
log4j.appender.logfile.layout=org.apache.log4j.PatternLayout
log4j.appender.logfile.layout.ConversionPattern=%d %p [%c] - %m%n

三、代码类

import org.apache.log4j.Logger;
import java.io.PrintWriter;
import java.io.Serializable;
import java.io.StringWriter;

/**
 * @Author: zwj
 * @Date: 2020/4/21 16:22
 * @Version 1.0
 *
 * 日志记录类
 */
public class LogUtils implements Serializable {

    private static Logger log = Logger.getLogger(LogUtils.class);

    /**
     * 是否开启Debug
     */
    public static boolean isDebug = log.isDebugEnabled();
    public static boolean isinfo = log.isInfoEnabled();

    private static String debug = "debug";
    private static String info = "info";
    private static String error = "error";
    private static String warn = "warn";



    /*** 获取输出信息的代码的位置 ***/
   private static String location = "";

    public LogUtils(Class<? extends Object> clazz) {

    }

    /**
     * 获取行号和传入类的信息
     */
   private static StackTraceElement[] stacks = Thread.currentThread().getStackTrace();



        /**
         * Debug 输出
         * @param
         * @param
         */
        public static void debug(Object object){
            if(!isDebug)
                return ;
            try {
                String location = getLocation(object,debug);
            }catch (Exception e){
                // TODO: handle exception
                e.printStackTrace();
            }
        }


        /**
         * warn 输出
         */
        public static void warn(Object object){

            try {
                String location = getLocation(object,warn);
            }catch (Exception e){
                // TODO: handle exception
                e.printStackTrace();
            }
        }

        /**
         * 异常填充值输出
         */
        public static void  info(Object object){

            if(!isinfo)
                return ;
            try {
                String location = getLocation(object,info);

            }catch (Exception e){

                // TODO: handle exception
                e.printStackTrace();
            }
        }

    /**
     * 异常填充值输出
     */
    public static void  error(Object object){

        try {

            String location = getLocation(object,error);

        }catch (Exception e){

            // TODO: handle exception
            e.printStackTrace();
        }

    }

        /**
         * 异常填充输出
         */
        public static void fmtError(Object object) {

        }


     public  static  String getLocation(Object object,String type){


         location = stacks[2].getClassName() + "." + stacks[2].getMethodName()
                 + "  [  " + stacks[2].getLineNumber() + "  ]  ";

         /*** 是否是异常  ***/
         if (object instanceof Exception) {
             Exception e = (Exception) object;
             StringWriter sw = new StringWriter();
             e.printStackTrace(new PrintWriter(sw, true));
             String str = sw.toString();
             getType(location,type,str);
         } else {
             getType(location,type,object.toString());
         }
       return     location;
      }


      public  static void  getType(String location,String type,String string){

            switch (type){
                case "debug":
                    log.debug(location+"[  "+string+"  ]");
                    break;
                case "info":
                    log.info(location+"[  "+string+"  ]");
                    break;
                case "warn":
                    log.warn(location+"[  "+string+"  ]");
                    break;
                case "error":
                    log.error(location+"[  "+string+"  ]");
                    break;
            }



      }


    }