springboot通过session实现单点登入_springboot session监听器用户登录-优快云博客

本文链接：https://blog.youkuaiyun.com/nanxiang11/article/details/121653323

效果图走起

在这里插入图片描述

另外开一个浏览器

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原来的页面刷新一下

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发现他已经被挤下线

代码部分

package com.nx.j2ee.service;

import org.springframework.stereotype.Service;

import javax.servlet.http.HttpSession;
import java.util.HashMap;
import java.util.Map;

@Service
public class OnlineService {
    private Map<String, HttpSession> UserMap = new HashMap<>();

    public HttpSession getUserMap(String name) {
        return UserMap.get(name);
    }

    public void setUserMap(String name, HttpSession httpSession) {
        UserMap.put(name, httpSession);
    }

    public void delectUserMap(String name){
        UserMap.remove(name);
    }

    public int shownum(){
        return UserMap.size();
    }

    public Map<String, HttpSession> showall(){
        return UserMap;
    }
}

登入controller

package com.nx.j2ee.controller;

import com.nx.j2ee.entity.UserEntity;
import com.nx.j2ee.service.OnlineService;
import com.nx.j2ee.service.UserService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestParam;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpSession;

@Controller
public class User {

    @Autowired
    private UserService userService;

    @Autowired
    private OnlineService onlineService;

    /**
     * @Description : 登入显示
     * @Author : 南巷的花猫
     * @Date : 2021/11/23 14:02
    */
    @GetMapping("/login")
    public String showlogin(){
        return "user/Login";
    }

    /**
     * @Description : 获取登入信息
     * @Author : 南巷的花猫
     * @Date : 2021/11/23 14:03
    */
    @PostMapping("/login")
    public String setlogin(@RequestParam("name") String name,
                           @RequestParam("password") String password, Model model,
                           HttpSession httpSession){

        UserEntity userEntity = userService.login(name, password);

        if (userEntity != null){
            if(onlineService.getUserMap(name) != null){
                onlineService.getUserMap(name).invalidate();
            }
            httpSession.setAttribute("userinfo", userEntity);
            onlineService.setUserMap(name, httpSession);
            return "redirect:/";
        }else {
            model.addAttribute("eroor", "用户名或者密码出错");
            return "user/Login";
        }
    }

    @GetMapping("/downline")
    public String downline(HttpSession httpSession){

        UserEntity userEntity = (UserEntity) httpSession.getAttribute("userinfo");
        onlineService.delectUserMap(userEntity.getName());
        httpSession.invalidate();
        return "redirect:/";
    }
}

首页controller

package com.nx.j2ee.controller;

import com.nx.j2ee.entity.UserEntity;
import com.nx.j2ee.service.OnlineService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.web.bind.annotation.GetMapping;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpSession;
import java.util.Map;
import java.util.Set;


@Controller
public class Index {

    @Autowired
    private OnlineService onlineService;

    private boolean select = false;

    @GetMapping("/")
    public String showindex(Model model, HttpSession httpSession){

        UserEntity userinfo = (UserEntity) httpSession.getAttribute("userinfo");
        if (userinfo != null){
            this.select = true;
        }else {
            this.select = false;
        }
        int onlinenum = onlineService.shownum();
        Set<String> userset = onlineService.showall().keySet();

        model.addAttribute("onlinenum", onlinenum);
        model.addAttribute("userinfo", userinfo);
        model.addAttribute("userset", userset);
        model.addAttribute("select", this.select);
        return "home/index";
    }
}

HTML页面

<!DOCTYPE html>
<html xmlns="http://www.w3.org/1999/xhtml"
      xmlns:th="http://www.thymeleaf.org">
<head>
    <meta charset="UTF-8">
    <link rel="stylesheet" href="/layui/css/layui.css">
    <title>首页</title>
</head>
<body>
<div class="layui-container">
    <div>
        <ul class="layui-nav layui-bg-green" lay-filter="">
            <li class="layui-nav-item">
                <a href="">在线人数<span class="layui-badge" th:text="${onlinenum}"></span></a>
            </li>
            <li class="layui-nav-item">
                <a th:href="@{/PTcourse}">普通课程</a>
            </li>
            <li class="layui-nav-item">
                <a th:href="@{/VIPcourse}">vip课程</a>
            </li>
            <li class="layui-nav-item">
                <a th:href="@{/GZcourse}">贵族课程</a>
            </li>
            <li class="layui-nav-item" style="float: right">
                <a href="" th:if="${not select}">游客</a>
                <a href="" th:if="${userinfo}" th:text="${userinfo.name}"></a>
                <dl class="layui-nav-child">
                    <dd th:if="${select}"><span style="color: #2d6086">等级:&nbsp;</span><span style="color: #0C0C0C" th:text="${userinfo.getTest1()}"></span></dd>
                    <dd><a href="javascript:;">修改信息</a></dd>
                    <dd><a href="javascript:;">安全管理</a></dd>
                    <dd><a th:href="@{/downline}" th:if="${select}">下线</a></dd>
                    <dd><a th:href="@{/login}" th:if="${not select}">登入</a></dd>
                </dl>
            </li>
        </ul>
    </div>
    <div style="margin-top: 20px;padding: 0px 50px 0px 50px">
        <div>
            <h3 style="color: #ac0d22">在线用户列表</h3>
        </div>
        <div th:each="username:${userset}">
            <p th:text="${username}"></p>
        </div>
    </div>
</div>
<script src="/layui/layui.js"></script>
<script>
  layui.use(['layer', 'form'], function(){
    var layer = layui.layer
            ,form = layui.form;

    layer.msg('追求极简');
  });
</script>
</body>
</html>