Spring MVC控制层判断登录 ,登录失败则返回提示信息

给自己做个笔记,该文主要是利用session做传值的作用，都是些基本的就不多说了。

request.getSession().setAttribute("login", su);

java代码

package com.arvato.controller;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

import org.springframework.beans.factory.annotation.Autowired;

import org.springframework.stereotype.Controller;

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

import org.springframework.web.servlet.ModelAndView;

import com.arvato.model.SaicUser;

import com.arvato.service.SaicUserService;

@Controller

public class SaicUserController {

@Autowired
private SaicUserService saicUserService;

@RequestMapping("saicUser/loginIn")
public ModelAndView loginIn(HttpServletRequest request,HttpServletResponse response) {

String name = request.getParameter("userName");
String pwd = request.getParameter("pw");
pwd = pwd.trim().toLowerCase();

//给密码加密
//String passMD5 = StringUtiles.getMD5(pwd);

//调用查询方法
SaicUser user = saicUserService.findSaicUser(name,pwd);

if(user == null){
ModelAndView mav = new ModelAndView("redirect:/login.jsp"); 
SaicUser su = new SaicUser();
su.setLoginInfo("用户名或密码不正确 ！");
request.getSession().setAttribute("login", su);
    return mav; 
}

System.out.println("------》用户: " + name + " 登录成功 ！");

ModelAndView mav = new ModelAndView("jsp/instrument/list"); 
    return mav; 
}

}

login.jsp代码

  <div class="message">

                  ${login.loginInfo}    //获取seesionsetAttribute()的值

                        <%session.removeAttribute("login");%>

                  

                        ${SPRING_SECURITY_LAST_EXCEPTION.message}

                        <%session.removeAttribute("SPRING_SECURITY_LAST_EXCEPTION");%>

  </div>