Spring Boot+Socket实现与html页面的长连接，客户端给服务器端发消息，服务器给客户端轮询发送消息，附案例源码

功能介绍

1. 客户端给所有在线用户发送消息
2. 客户端给指定在线用户发送消息
3. 服务器给客户端发送消息(轮询方式)

注意：socket只是实现一些简单的功能，具体的还需根据自身情况，代码稍微改造下

项目搭建

项目结构图

pom.xml

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.3.2.RELEASE</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>
    <groupId>com.cyb</groupId>
    <artifactId>socket_test</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <name>socket_test</name>
    <description>Demo project for Spring Boot</description>

    <properties>
        <java.version>1.8</java.version>
    </properties>

    <dependencies>
        <!-- springboot websocket -->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-websocket</artifactId>
        </dependency>
        <!--guava依赖-->
        <dependency>
            <groupId>com.google.guava</groupId>
            <artifactId>guava</artifactId>
            <version>18.0</version>
        </dependency>
        <!--fastjson依赖-->
        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>fastjson</artifactId>
            <version>1.2.46</version>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
            <exclusions>
                <exclusion>
                    <groupId>org.junit.vintage</groupId>
                    <artifactId>junit-vintage-engine</artifactId>
                </exclusion>
            </exclusions>
        </dependency>
    </dependencies>

    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>

</project>

appliccation.properties

SocketTestApplication.java(Spring Boot启动类)

WebSocketStompConfig.java

package com.cyb.socket.websocket;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.socket.server.standard.ServerEndpointExporter;

@Configuration
public class WebSocketStompConfig {
    //这个bean的注册,用于扫描带有@ServerEndpoint的注解成为websocket  ,如果你使用外置的tomcat就不需要该配置文件
    @Bean
    public ServerEndpointExporter serverEndpointExporter()
    {
        return new ServerEndpointExporter();
    }
}

WebSocket.java(Socket核心类)

package com.cyb.socket.websocket;

import java.io.IOException;
import java.util.Map;
import java.util.Set;
import java.util.concurrent.ConcurrentHashMap;
import javax.websocket.OnClose;
import javax.websocket.OnError;
import javax.websocket.OnMessage;
import javax.websocket.OnOpen;
import javax.websocket.Session;
import javax.websocket.server.PathParam;
import javax.websocket.server.ServerEndpoint;
import com.alibaba.fastjson.JSON;
import com.alibaba.fastjson.JSONObject;
import com.google.common.collect.Maps;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.stereotype.Component;

/**
 * @Author：陈彦斌
 * @Description：Socket核心类
 * @Date： 2020-07-26
 */

@Component
@ServerEndpoint(value = "/connectWebSocket/{userId}")
public class WebSocket {

    private Logger logger = LoggerFactory.getLogger(this.getClass());
    /**
     * 在线人数
     */
    public static int onlineNumber = 0;
    /**
     * 以用户的姓名为key，WebSocket为对象保存起来
     */
    private static Map<String, WebSocket> clients = new ConcurrentHashMap<String, WebSocket>();
    /**
     * 会话
     */
    private Session session;
    /**
     * 用户名称
     */
    private String userId;

    /**
     * 建立连接
     *
     * @param session
     */
    @OnOpen
    public void onOpen(@PathParam("userId") String userId, Session session) {
        onlineNumber++;
        System.out.println("现在来连接的客户id：" + session.getId() + "用户名：" + userId);
        //logger.info("现在来连接的客户id："+session.getId()+"用户名："+userId);
        this.userId = userId;
        this.session = session;
        System.out.println("有新连接加入！ 当前在线人数" + onlineNumber);
        //  logger.info("有新连接加入！ 当前在线人数" + onlineNumber);
        try {
            //messageType 1代表上线 2代表下线 3代表在线名单 4代表普通消息
            //先给所有人发送通知，说我上线了
            Map<String, Object> map1 = Maps.newHashMap();
            map1.put("messageType", 1);
            map1.put("userId", userId);
            sendMessageAll(JSON.toJSONString(map1), userId);

            //把自己的信息加入到map当中去
            clients.put(userId, this);
            System.out.println("有连接关闭！ 当前在线人数" + onlineNumber);
            //logger.info("有连接关闭！ 当前在线人数" + clients.size());
            //给自己发一条消息：告诉自己现在都有谁在线
            Map<String, Object> map2 = Maps.newHashMap();
            map2.put("messageType", 3);
            //移除掉自己
            Set<String> set = clients.keySet();
            map2.put("onlineUsers", set);
            sendMessageTo(JSON.toJSONString(map2), userId);
        } catch (IOException e) {
            System.out.println(userId + "上线的时候通知所有人发生了错误");
            //logger.info(userId+"上线的时候通知所有人发生了错误");
        }
    }

    @OnError
    public void onError(Session session, Throwable error) {
        //logger.info("服务端发生了错误"+error.getMessage());
        //error.printStackTrace();
        System.out.println("服务端发生了错误:" + error.getMessage());
    }

    /**
     * 连接关闭
     */
    @OnClose
    public void onClose() {
        onlineNumber--;
        //webSockets.remove(this);
        clients.remove(userId);
        try {
            //messageType 1代表上线 2代表下线 3代表在线名单  4代表普通消息
            Map<String, Object> map1 = Maps.newHashMap();
            map1.put("messageType", 2);
            map1.put("onlineUsers", clients.keySet());
            map1.put("userId", userId);
            sendMessageAll(JSON.toJSONString(map1), userId);
        } catch (IOException e) {
            System.out.println(userId + "下线的时候通知所有人发生了错误");
            //logger.info(userId+"下线的时候通知所有人发生了错误");
        }
        //logger.info("有连接关闭！ 当前在线人数" + onlineNumber);
        //logger.info("有连接关闭！ 当前在线人数" + clients.size());
        System.out.println("有连接关闭！ 当前在线人数" + onlineNumber);
    }

    /**
     * 收到客户端的消息
     *
     * @param message 消息
     * @param session 会话
     */
    @OnMessage
    public void onMessage(String message, Session session) {
        try {
            //logger.info("来自客户端消息：" + message+"客户端的id是："+session.getId());
            System.out.println("来自客户端消息：" + message + " | 客户端的id是：" + session.getId());
            JSONObject jsonObject = JSON.parseObject(message);
            String textMessage = jsonObject.getString("message");
            String fromuserId = jsonObject.getString("userId");
            String touserId = jsonObject.getString("to");
            //如果不是发给所有，那么就发给某一个人
            //messageType 1代表上线 2代表下线 3代表在线名单  4代表普通消息
            Map<String, Object> map1 = Maps.newHashMap();
            map1.put("messageType", 4);
            map1.put("textMessage", textMessage);
            map1.put("fromuserId", fromuserId);
            if (touserId.equals("All")) {
                map1.put("touserId", "所有人");
                sendMessageAll(JSON.toJSONString(map1), fromuserId);
            } else {
                map1.put("touserId", touserId);
                System.out.println("开始推送消息给" + touserId);
                sendMessageTo(JSON.toJSONString(map1), touserId);
            }
        } catch (Exception e) {
            e.printStackTrace();
            //logger.info("发生了错误了");
        }

    }

    /**
     * 给指定的用户发送消息
     *
     * @param message
     * @param TouserId
     * @throws IOException
     */
    public void sendMessageTo(String message, String TouserId) throws IOException {
        for (WebSocket item : clients.values()) {
            System.out.println("给指定的在线用户发送消息,在线人员名单：【" + item.userId.toString() + "】发送消息:" + message);
            if (item.userId.equals(TouserId)) {
                item.session.getAsyncRemote().sendText(message);
                break;
            }
        }
    }

    /**
     * 给所有用户发送消息
     *
     * @param message    数据
     * @param FromuserId
     * @throws IOException
     */
    public void sendMessageAll(String message, String FromuserId) throws IOException {
        for (WebSocket item : clients.values()) {
            System.out.println("给所有在线用户发送给消息，在线人员名单：【" + item.userId.toString() + "】发送消息:" + message);
            item.session.getAsyncRemote().sendText(message);
        }
    }

    /**
     * 给所有在线用户发送消息
     *
     * @param message 数据
     * @throws IOException
     */
    public void sendMessageAll(String message) throws IOException {
        for (WebSocket item : clients.values()) {
            System.out.println("服务器给所有在线用户发送消息，当前在线人员为【" + item.userId.toString() + "】发送消息:" + message);
            item.session.getAsyncRemote().sendText(message);
        }
    }

    /**
     * 获取在线用户数
     *
     * @return
     */
    public static synchronized int getOnlineCount() {
        return onlineNumber;
    }
}

TestController.java(前端控制器)

package com.cyb.socket.websocket;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.*;
import java.io.IOException;

@Controller
@RequestMapping("testMethod")
public class TestController {
    @Autowired
    private WebSocket webSocket;

    /**
     * 给指定的在线用户发送消息
     * @param userId
     * @param msg
     * @return
     * @throws IOException
     */
    @ResponseBody
    @GetMapping("/sendTo")
    public String sendTo(@RequestParam("userId") String userId,@RequestParam("msg") String msg) throws IOException {
        webSocket.sendMessageTo(msg,userId);
        return "推送成功";
    }

    /**
     * 给所有在线用户发送消息
     * @param msg
     * @return
     * @throws IOException
     * @throws IOException
     */
    @ResponseBody
    @PostMapping("/sendAll")
    public String sendAll(@RequestBody String msg) throws IOException, IOException {
        webSocket.sendMessageAll(msg);
        return "推送成功";
    }
}

SocketTask.java(轮询调度往客户端推送消息)

package com.cyb.socket.schedule;

import com.cyb.socket.websocket.WebSocket;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.scheduling.annotation.Scheduled;
import org.springframework.stereotype.Component;

import java.io.IOException;
import java.text.SimpleDateFormat;
import java.util.Date;

@Component
public class SocketTask {
    @Autowired
    private WebSocket webSocket;
    private SimpleDateFormat sdf =new SimpleDateFormat("yyyy-MM-dd HH:mm:ss SSS" );
    //5秒轮询一次
    @Scheduled(fixedRate = 5000)
    public void sendClientData() throws IOException {
        String msg="{"message":"你好","userId":"002","to":"All"}";
        webSocket.sendMessageAll(msg);
        System.out.println("消息推送时间："+ sdf.format(new Date()));
    }
}

测试网页

index.html

<!DOCTYPE HTML>
<html>
<head>
    <title>Test My WebSocket</title>
</head>
 
 
<body>
TestWebSocket
<input  id="text" type="text" style="500px"/>
<button onclick="send()">SEND MESSAGE</button>
<button onclick="closeWebSocket()">CLOSE</button>
<div id="message"></div>
</body>
 
<script type="text/javascript">
    var websocket = null;
 
 
    //判断当前浏览器是否支持WebSocket
    if('WebSocket' in window){
        //连接WebSocket节点
        websocket = new WebSocket("ws://localhost:8083/connectWebSocket/001");
    }
    else{
        alert('Not support websocket')
    }
 
 
    //连接发生错误的回调方法
    websocket.onerror = function(){
        setMessageInnerHTML("error");
    };
 
 
    //连接成功建立的回调方法
    websocket.onopen = function(event){
        setMessageInnerHTML("open");
    }
 
 
    //接收到消息的回调方法
    websocket.onmessage = function(event){
        setMessageInnerHTML(event.data);
    }
 
 
    //连接关闭的回调方法
    websocket.onclose = function(){
        setMessageInnerHTML("close");
    }
 
 
    //监听窗口关闭事件，当窗口关闭时，主动去关闭websocket连接，防止连接还没断开就关闭窗口，server端会抛异常。
    window.onbeforeunload = function(){
        websocket.close();
    }
 
 
    //将消息显示在网页上
    function setMessageInnerHTML(innerHTML){
        document.getElementById('message').innerHTML += innerHTML + '<br/>';
    }
 
 
    //关闭连接
    function closeWebSocket(){
        websocket.close();
    }
 
 
    //发送消息
    function send(){
        var message = document.getElementById('text').value;
        websocket.send(message);
    }
</script>
</html>

index2.html

<!DOCTYPE HTML>
<html>
<head>
    <title>Test My WebSocket</title>
</head>
 
 
<body>
TestWebSocket
<input  id="text" type="text" style="500px" />
<button onclick="send()">SEND MESSAGE</button>
<button onclick="closeWebSocket()">CLOSE</button>
<div id="message"></div>
</body>
 
<script type="text/javascript">
    var websocket = null;
 
 
    //判断当前浏览器是否支持WebSocket
    if('WebSocket' in window){
        //连接WebSocket节点
        websocket = new WebSocket("ws://localhost:8083/connectWebSocket/002");
    }
    else{
        alert('Not support websocket')
    }
 
 
    //连接发生错误的回调方法
    websocket.onerror = function(){
        setMessageInnerHTML("error");
    };
 
 
    //连接成功建立的回调方法
    websocket.onopen = function(event){
        setMessageInnerHTML("open");
    }
 
 
    //接收到消息的回调方法
    websocket.onmessage = function(event){
        setMessageInnerHTML(event.data);
    }
 
 
    //连接关闭的回调方法
    websocket.onclose = function(){
        setMessageInnerHTML("close");
    }
 
 
    //监听窗口关闭事件，当窗口关闭时，主动去关闭websocket连接，防止连接还没断开就关闭窗口，server端会抛异常。
    window.onbeforeunload = function(){
        websocket.close();
    }
 
 
    //将消息显示在网页上
    function setMessageInnerHTML(innerHTML){
        document.getElementById('message').innerHTML += innerHTML + '<br/>';
    }
 
 
    //关闭连接
    function closeWebSocket(){
        websocket.close();
    }
 
 
    //发送消息
    function send(){
        var message = document.getElementById('text').value;
        websocket.send(message);
    }
</script>
</html>

项目地址

链接：https://pan.baidu.com/s/1yiAXTkCjHac-F3S1HFyNJQ 
提取码：53tp 

功能演示

 客户端给所有在线用户发消息

客户端给指定在线用户发送消息

 

服务器给客户端发送消息(轮询方式)

 注意需要加上这些注解

演示

通过前端控制器给指定用户发送消息

演示