Java中Spring Boot+Socket实现与html页面的长连接实例详解

<?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>

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();
 }
}

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;
 }
}

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";
 }
}

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()));
 }
}

<!DOCTYPE HTML>
<html>
<head>
 <title>Test My WebSocket</title>
</head>
 
 
<body>
TestWebSocket
<input id="text" type="text" style="width: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>

<!DOCTYPE HTML>
<html>
<head>
 <title>Test My WebSocket</title>
</head>
 
 
<body>
TestWebSocket
<input id="text" type="text" style="width: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>