04-信息管理系统--log4j日志的使用

首先将log4j架包导入WebRoot下的lib文件中，然后右击进行Build Path,再把log4j的配置文件放到src下

配置好，在哪里打印呢？

在service中进行打印
service包下的USerServiceImpl类代码更改如下

package com.lzy.service.imp;

import org.apache.log4j.Logger;

import com.lzy.dao.UserDao;
import com.lzy.dao.impl.UserDaoImpl;
import com.lzy.pojo.User;
import com.lzy.service.UserService;

public class UserServiceImpl implements UserService {
	//声明日志对象
	Logger logger=Logger.getLogger(UserServiceImpl.class);
	//声明Dao层对象
	UserDao ud=new UserDaoImpl();
	//用户登录
	@Override
	public User checkUserLoginService(String uname, String pwd) {
		//打印日志
		logger.debug(uname+"发起登录请求");
		User u=ud.checkUserLoginDao(uname, pwd);
		//判断
		if(u!=null){
			logger.debug(uname+"登陆成功");
			
		}else{
			logger.debug(uname+"登录失败");
			
		}
		
		return u;
	}

}

servlet包下的UserServlet代码更改如下

package com.lzy.servlet;


import java.io.IOException;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.apache.log4j.Logger;

import com.lzy.pojo.User;
import com.lzy.service.UserService;
import com.lzy.service.imp.UserServiceImpl;

public class UserServlet extends HttpServlet {
	//声明日志对象
	Logger logger=Logger.getLogger(UserServlet.class);
	
@Override
protected void service(HttpServletRequest req, HttpServletResponse resp)
		throws ServletException, IOException {
	//设置请求编码格式
	req.setCharacterEncoding("utf-8");
	//设置响应编码格式
	resp.setCharacterEncoding("text/html;charset=utf-8");
	//获取操作符
	String oper=req.getParameter("oper");
	if("login".equals(oper)){
		//响应登陆操作
		checkUserLogin(req,resp);
	}else if("reg".equals(oper)){
		//响应注册操作
	}else{ 
		logger.debug("响应错误"+oper);
	}	
}

private void checkUserLogin(HttpServletRequest req, HttpServletResponse resp) {
	//获取请求信息
	String uname=req.getParameter("uname");
	String pwd=req.getParameter("pwd");
	//处理请求信息
	        //校验
	         UserService us=new UserServiceImpl();
	        User u=us.checkUserLoginService(uname, pwd);
	         
	
	
}
}

保存后启动tomcat，测试后控制台输出如下：

打开D盘，有一个axis.log文件，打开后日志如下