干货！SSM实现登录和退出

package com.ddkjt.controller;

import javax.annotation.Resource;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;

import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;

import com.ddkjt.po.User;
import com.ddkjt.service.UserService;

@Controller("userController")
@RequestMapping("/")
public class UserController {
    
    @Resource(name="userService")
    private UserService userService;

    public UserService getUserService() {
        return userService;
    }

    public void setUserService(UserService userService) {
        this.userService = userService;
    }
    
    //登录
    @RequestMapping(value = "/login", method = RequestMethod.GET)
    public String login() {
        return "login";
    }
    
    @RequestMapping(value = "/login", method = RequestMethod.POST)
    public String login(User u,Model model,HttpServletResponse response,HttpServletRequest request) {
        User user = userService.login(u);
        //判断用户是否存在
        if(user != null){
            request.getSession().setAttribute("user", user);
            //判断用户是否点击了登录保留一周
            if(request.getParameter("login_time") == "on"){
                request.getSession().setMaxInactiveInterval(7*24*60*60);
            }else{
                request.getSession().setMaxInactiveInterval(2*60*60);
            }
            return "redirect:index";
        }else{
            model.addAttribute("msg","账号和密码不匹配，请重新输入");
            return "login";
        }
    }
    
    //退出登录
    @RequestMapping("/logout")
    public String logout(HttpSession session) {
        session.invalidate();
        return "redirect:login";
    }
    
}

package com.ddkjt.tool;

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

import org.springframework.web.servlet.HandlerInterceptor;
import org.springframework.web.servlet.ModelAndView;

public class SecurityInterceptor implements HandlerInterceptor{

    @Override
    public void afterCompletion(HttpServletRequest arg0, HttpServletResponse arg1, Object arg2, Exception arg3) throws Exception {
        
    }

    @Override
    public void postHandle(HttpServletRequest arg0, HttpServletResponse arg1, Object arg2, ModelAndView arg3) throws Exception {
        
    }

    @Override
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object o) throws Exception {
        String basePath = request.getScheme() + "://" + request.getServerName() + ":" + request.getServerPort() + request.getContextPath() + "/";
        //判断session是否存在、是否是login页面，访问路径是否包含static
        if(request.getSession().getAttribute("user") == null && !request.getRequestURL().toString().equals(basePath+"login") && !request.getRequestURL().toString().contains("static")) {
            response.sendRedirect(request.getContextPath()+"/login");
            return false;
        }
        return true;
    }

}

<mvc:interceptors>
    <mvc:interceptor>
        <mvc:mapping path="/**"/>
        <bean class="com.ddkjt.tool.SecurityInterceptor"/>
    </mvc:interceptor>
</mvc:interceptors>

<form class="layui-form" method="post" action="./login">
      <div class="layui-form-item">
              <input type="text" name="user_name" placeholder="账号" class="layui-input">
        </div>
        <div class="layui-form-item">
              <input type="password" name="user_pwd" placeholder="密码" class="layui-input">
        </div>
        <div class="layui-form-item">
              <input type="checkbox" name="login_time" title="登录保留一周" checked>
        </div>
        <div class="layui-form-item">
            <input type="submit" class="layui-btn layui-btn-normal layui-btn-fluid" value="登录" />
        </div>
</form>
<script src="static/layui/layui.js" charset="utf-8"></script>
<script src="static/pear/pear.js"></script>
<script type="text/javascript">
    layui.use(['toast','jquery'],function() {
        var $ = layui.jquery;
        var toast = layui.toast;
        if('${msg}' != ''){
            toast.error({title: '错误信息',message: '${msg}',position: 'topCenter'});
        }
        $(".layui-btn").click(function(){
            if($('input[name="user_name"]').val() == '' || $('input[name="user_pwd"]').val() == ''){
                toast.error({title: '错误信息',message: '账号和密码不能为空，请输入',position: 'topCenter'});
                return false;
            }
        });
    });
</script>