1、添加pom依赖

<!-- websocket -->
<dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-websocket</artifactId>
</dependency>

2、创建一个config文件夹，在config文件夹中创建一个 WebSocketConfig.java 类

import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.socket.server.standard.ServerEndpointExporter;@Configuration
public class WebSocketConfig {/*** 注入一个ServerEndpointExporter,该Bean会自动注册使用@ServerEndpoint注解申明的websocket endpoint*/@Beanpublic ServerEndpointExporter serverEndpointExporter() {return new ServerEndpointExporter();}}

3、新建一个 component 文件夹，并且在 component 文件夹中新建  WebSocketServer.java 类

import cn.hutool.json.JSONArray;
import cn.hutool.json.JSONObject;
import cn.hutool.json.JSONUtil;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.stereotype.Component;import javax.websocket.*;
import javax.websocket.server.PathParam;
import javax.websocket.server.ServerEndpoint;
import java.util.Map;
import java.util.concurrent.ConcurrentHashMap;/*** @author websocket服务*/
@ServerEndpoint(value = "/imserver/{username}")
@Component
public class WebSocketServer {private static final Logger log = LoggerFactory.getLogger(WebSocketServer.class);/*** 记录当前在线连接数*/public static final Map<String, Session> sessionMap = new ConcurrentHashMap<>();/*** 连接建立成功调用的方法*/@OnOpenpublic void onOpen(Session session, @PathParam("username") String username) {sessionMap.put(username, session);log.info("有新用户加入，username={}, 当前在线人数为：{}", username, sessionMap.size());JSONObject result = new JSONObject();JSONArray array = new JSONArray();result.set("users", array);for (Object key : sessionMap.keySet()) {JSONObject jsonObject = new JSONObject();jsonObject.set("username", key);// {"username", "zhang", "username": "admin"}array.add(jsonObject);}
//        {"users": [{"username": "zhang"},{ "username": "admin"}]}sendAllMessage(JSONUtil.toJsonStr(result));  // 后台发送消息给所有的客户端}/*** 连接关闭调用的方法*/@OnClosepublic void onClose(Session session, @PathParam("username") String username) {sessionMap.remove(username);log.info("有一连接关闭，移除username={}的用户session, 当前在线人数为：{}", username, sessionMap.size());}/*** 收到客户端消息后调用的方法* 后台收到客户端发送过来的消息* onMessage 是一个消息的中转站* 接受 浏览器端 socket.send 发送过来的 json数据* @param message 客户端发送过来的消息*/@OnMessagepublic void onMessage(String message, Session session, @PathParam("username") String username) {log.info("服务端收到用户username={}的消息:{}", username, message);JSONObject obj = JSONUtil.parseObj(message);String toUsername = obj.getStr("to"); // to表示发送给哪个用户，比如 adminString text = obj.getStr("text"); // 发送的消息文本  hello// {"to": "admin", "text": "聊天文本"}Session toSession = sessionMap.get(toUsername); // 根据 to用户名来获取 session，再通过session发送消息文本if (toSession != null) {// 服务器端 再把消息组装一下，组装后的消息包含发送人和发送的文本内容// {"from": "zhang", "text": "hello"}JSONObject jsonObject = new JSONObject();jsonObject.set("from", username);  // from 是 zhangjsonObject.set("text", text);  // text 同上面的textthis.sendMessage(jsonObject.toString(), toSession);log.info("发送给用户username={}，消息：{}", toUsername, jsonObject.toString());} else {log.info("发送失败，未找到用户username={}的session", toUsername);}}@OnErrorpublic void onError(Session session, Throwable error) {log.error("发生错误");error.printStackTrace();}/*** 服务端发送消息给客户端*/private void sendMessage(String message, Session toSession) {try {log.info("服务端给客户端[{}]发送消息{}", toSession.getId(), message);toSession.getBasicRemote().sendText(message);} catch (Exception e) {log.error("服务端发送消息给客户端失败", e);}}/*** 服务端发送消息给所有客户端*/private void sendAllMessage(String message) {try {for (Session session : sessionMap.values()) {log.info("服务端给客户端[{}]发送消息{}", session.getId(), message);session.getBasicRemote().sendText(message);}} catch (Exception e) {log.error("服务端发送消息给客户端失败", e);}}
}

 4、在你的token拦截里，放行该接口

 5、新建Vue页面，Im.vue

<template><div style="padding: 10px; margin-bottom: 50px"><el-row><el-col :span="4"><el-card style="width: 300px; height: 300px; color: #333"><div style="padding-bottom: 10px; border-bottom: 1px solid #ccc">在线用户<span style="font-size: 12px">（点击聊天气泡开始聊天）</span></div><div style="padding: 10px 0" v-for="user in users" :key="user.username"><span>{{ user.username }}</span><i class="el-icon-chat-dot-round" style="margin-left: 10px; font-size: 16px; cursor: pointer"@click="chatUser = user.username"></i><span style="font-size: 12px;color: limegreen; margin-left: 5px" v-if="user.username === chatUser">chatting...</span></div></el-card></el-col><el-col :span="20"><div style="width: 800px; margin: 0 auto; background-color: white;border-radius: 5px; box-shadow: 0 0 10px #ccc"><div style="text-align: center; line-height: 50px;">Web聊天室（{{ chatUser }}）</div><div style="height: 350px; overflow:auto; border-top: 1px solid #ccc" v-html="content"></div><div style="height: 200px"><textarea v-model="text" style="height: 160px; width: 100%; padding: 20px; border: none; border-top: 1px solid #ccc;border-bottom: 1px solid #ccc; outline: none"></textarea><div style="text-align: right; padding-right: 10px"><el-button type="primary" size="mini" @click="send">发送</el-button></div></div></div></el-col></el-row></div>
</template><script>import request from "@/utils/request";let socket;export default {name: "Im",data() {return {circleUrl: 'https://cube.elemecdn.com/3/7c/3ea6beec64369c2642b92c6726f1epng.png',user: {},isCollapse: false,users: [],chatUser: '',text: "",messages: [],content: ''}},created() {this.init()},methods: {send() {if (!this.chatUser) {this.$message({type: 'warning', message: "请选择聊天对象"})return;}if (!this.text) {this.$message({type: 'warning', message: "请输入内容"})} else {if (typeof (WebSocket) == "undefined") {console.log("您的浏览器不支持WebSocket");} else {console.log("您的浏览器支持WebSocket");// 组装待发送的消息 json// {"from": "zhang", "to": "admin", "text": "聊天文本"}let message = {from: this.user.username, to: this.chatUser, text: this.text}socket.send(JSON.stringify(message));  // 将组装好的json发送给服务端，由服务端进行转发this.messages.push({user: this.user.username, text: this.text})// 构建消息内容，本人消息this.createContent(null, this.user.username, this.text)this.text = '';}}},createContent(remoteUser, nowUser, text) {  // 这个方法是用来将 json的聊天消息数据转换成 html的。let html// 当前用户消息if (nowUser) { // nowUser 表示是否显示当前用户发送的聊天消息，绿色气泡html = "<div class=\"el-row\" style=\"padding: 5px 0\">\n" +"  <div class=\"el-col el-col-22\" style=\"text-align: right; padding-right: 10px\">\n" +"    <div class=\"tip left\">" + text + "</div>\n" +"  </div>\n" +"  <div class=\"el-col el-col-2\">\n" +"  <span class=\"el-avatar el-avatar--circle\" style=\"height: 40px; width: 40px; line-height: 40px;\">\n" +"    <img src=\"https://cube.elemecdn.com/3/7c/3ea6beec64369c2642b92c6726f1epng.png\" style=\"object-fit: cover;\">\n" +"  </span>\n" +"  </div>\n" +"</div>";} else if (remoteUser) {   // remoteUser表示远程用户聊天消息，蓝色的气泡html = "<div class=\"el-row\" style=\"padding: 5px 0\">\n" +"  <div class=\"el-col el-col-2\" style=\"text-align: right\">\n" +"  <span class=\"el-avatar el-avatar--circle\" style=\"height: 40px; width: 40px; line-height: 40px;\">\n" +"    <img src=\"https://cube.elemecdn.com/3/7c/3ea6beec64369c2642b92c6726f1epng.png\" style=\"object-fit: cover;\">\n" +"  </span>\n" +"  </div>\n" +"  <div class=\"el-col el-col-22\" style=\"text-align: left; padding-left: 10px\">\n" +"    <div class=\"tip right\">" + text + "</div>\n" +"  </div>\n" +"</div>";}console.log(html)this.content += html;},init() {this.user = sessionStorage.getItem("user") ? JSON.parse(sessionStorage.getItem("user")) : {}let username = this.user.username;let _this = this;if (typeof (WebSocket) == "undefined") {console.log("您的浏览器不支持WebSocket");} else {console.log("您的浏览器支持WebSocket");let socketUrl = "ws://localhost:9090/imserver/" + username;if (socket != null) {socket.close();socket = null;}// 开启一个websocket服务socket = new WebSocket(socketUrl);//打开事件socket.onopen = function () {console.log("websocket已打开");};//  浏览器端收消息，获得从服务端发送过来的文本消息socket.onmessage = function (msg) {console.log("收到数据====" + msg.data)let data = JSON.parse(msg.data)  // 对收到的json数据进行解析， 类似这样的： {"users": [{"username": "zhang"},{ "username": "admin"}]}if (data.users) {  // 获取在线人员信息_this.users = data.users.filter(user => user.username !== username)  // 获取当前连接的所有用户信息，并且排除自身，自己不会出现在自己的聊天列表里} else {// 如果服务器端发送过来的json数据 不包含 users 这个key，那么发送过来的就是聊天文本json数据//  // {"from": "zhang", "text": "hello"}if (data.from === _this.chatUser) {_this.messages.push(data)// 构建消息内容_this.createContent(data.from, null, data.text)}}};//关闭事件socket.onclose = function () {console.log("websocket已关闭");};//发生了错误事件socket.onerror = function () {console.log("websocket发生了错误");}}}}
}</script><style>
.tip {color: white;text-align: center;border-radius: 10px;font-family: sans-serif;padding: 10px;width:auto;display:inline-block !important;display:inline;
}.right {background-color: deepskyblue;
}
.left {background-color: forestgreen;
}
</style>

最后设置路由就好啦 

{path: 'im',name: 'Im',component: () => import("@/views/Im"),
},