Log4j简单配置

2023-01-22 08:04:47

Log4j是一组强大的日志组件，在项目中时常需要用它提供一些信息，这两天学习了一下它的简单配置。

第一步，我们需要导入log4j-1.2.14.jar到lib目录下

第二步，在src下建立log4j.properties文件。添加如下内容

 log4j.properties

 log4j.rootLogger =INFO,stdout

 log4j.logger.sedion=INFO,db

 log4j.logger.W=WARN,W

 log4j.logger.E=ERROR,E

 #输出到控制台

 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 =  %d{ABSOLUTE} %5p %c{1}:%L - %m%n

 #输出WARN级别日志

 log4j.appender.W =org.apache.log4j.RollingFileAppender

 log4j.appender.W.File =${catalina.home}/logs/Test/Test_W.log

 log4j.appender.W.Append =true

 log4j.appender.W.Threshold =WARN

 log4j.appender.W.layout = org.apache.log4j.PatternLayout

 log4j.appender.W.layout.ConversionPattern = %-d{yyyy-MM-dd HH:mm:ss}  [ %t:%r ] - [ %p ]  %m%n

 #输出ERROR级别日志

 log4j.appender.E = org.apache.log4j.RollingFileAppender

 log4j.appender.E.File = ${catalina.home}/logs/Test/Test_E.log

 log4j.appender.E.Append = true

 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

 #######################

 # JDBC Appender  

 #######################

 log4j.appender.db=org.apache.log4j.jdbc.JDBCAppender

 log4j.appender.db.BufferSize=1

 log4j.appender.db.driver=com.mysql.jdbc.Driver

 log4j.appender.db.URL=jdbc:mysql://localhost:3306/test

 log4j.appender.db.user=root

 log4j.appender.db.password=123

 log4j.appender.db.sql=insert into operate_log(class,method,createtime,loglevel,logmsg,username) values ("%C","%M","%d{yyyy-MM-dd HH\:mm\:ss}","%p","%m","%X{username}")

 log4j.appender.db.layout=org.apache.log4j.PatternLayout

新建一个数据库test和一张日志表operate_log。

可以看到数据库中有个username动态字段，所以我们要写个过滤器

 package config.filter;

 import java.io.IOException;

 import javax.servlet.Filter;

 import javax.servlet.FilterChain;

 import javax.servlet.FilterConfig;

 import javax.servlet.ServletException;

 import javax.servlet.ServletRequest;

 import javax.servlet.ServletResponse;

 import javax.servlet.http.HttpServletRequest;

 import org.apache.log4j.MDC;

 public class Log4jFilter implements Filter

 {

     private final static int DEDAULT_USERID = 0;

     public void destroy()

     {

     }

     public void doFilter(ServletRequest req, ServletResponse rep,

             FilterChain chain) throws IOException, ServletException

     {

         HttpServletRequest request = (HttpServletRequest)req;

         String username = request.getParameter("username");

         if(username == null)

         {

             MDC.put("username", DEDAULT_USERID);

         }

         else

         {

                 System.out.println("登陆名--"+username);

                 MDC.put("username", username);

         }

         chain.doFilter(req, rep);

     }

     public void init(FilterConfig arg0) throws ServletException

     {

     }

 }

然后需要在web.xml中进行log4j.properties和过滤器的配置.

<!-- log4j配置 -->

    <context-param>

        <param-name>log4jConfigLocation</param-name>

        <param-value>classpath:log4j.properties</param-value>

    </context-param>

    <listener>

       <listener-class>org.springframework.web.util.Log4jConfigListener</listener-class>

    </listener>

    <!-- 过滤器配置 -->

     <filter>

        <filter-name>LogResFilter</filter-name>

        <filter-class>config.filter.Log4jFilter</filter-class>

    </filter>

    <filter-mapping>

        <filter-name>LogResFilter</filter-name>

        <url-pattern>*.do</url-pattern>

    </filter-mapping>

第三步，至此我们配置已经全部完成，简单写个登陆来验证一下。

jsp页面很简单，代码便不列出来了.

写个登陆实现类.

package sedion.zhr.controller;

import java.util.List;

import javax.annotation.Resource;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

import org.apache.commons.logging.Log;

import org.apache.commons.logging.LogFactory;

import org.apache.log4j.Logger;

import org.springframework.stereotype.Controller;

import org.springframework.web.bind.annotation.RequestMapping;

import sedion.zhr.beans.UserBean;

import sedion.zhr.service.iml.UserServiceIml;

@Controller

@RequestMapping("/action")

public class LoginController

{

    private static final Logger log_w= Logger.getLogger("W");

    private static final Logger log_e = Logger.getLogger("E");

    private Log logger = LogFactory.getLog(this.getClass());  

    @Resource(name = "UserService")

    private UserServiceIml serviceIml;

    @RequestMapping("/login.do")

    public String login(UserBean bean,HttpServletRequest request,HttpServletResponse response) throws Exception

    {

        List<UserBean> beans = this.serviceIml.finduser(new String[]{bean.getUsername(),bean.getPassword()});

        if(!beans.isEmpty())

        {

            log_w.warn("登陆成功--");

            logger.info("登陆成功");

            return "/index";

        }

        else

        {

            log_e.error("登陆失败--");

            logger.error("登陆失败");

            return "/login";

        }

    }

}