Step 1: Introduce POM dependencies
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-websocket</artifactId>
</dependency>Step 2: The java code is as follows
package com.ruoyi.web.controller.websoket;
import org.springframework.stereotype.Component;
import javax.annotation.PostConstruct;
import javax.websocket.*;
import javax.websocket.server.ServerEndpoint;
import java.io.IOException;
import java.util.HashMap;
import java.util.Map;
import java.util.concurrent.CopyOnWriteArraySet;
import java.util.concurrent.atomic.AtomicInteger;
@ServerEndpoint(value = "/webSocket/dealWith")
@Component
public class WebSocketServer {
public static String userId = null;
@PostConstruct
public void init() {
System.out.println("websocket 加载");
}
private static final AtomicInteger OnlineCount = new AtomicInteger(0);
// concurrent包的线程安全Set，用来存放每个客户端对应的Session对象。
private static CopyOnWriteArraySet<Session> SessionSet = new CopyOnWriteArraySet<Session>();
public static Map<String,Session> map = new HashMap<>();
/**
* 连接建立成功调用的方法并打印出相关的数据
*/
@OnOpen
public void onOpen(Session session) {
SessionSet.add(session);
map.put(userId,session);
int cnt = OnlineCount.incrementAndGet(); // 在线数加1
System.out.printf("有连接加入，当前连接数为："+ cnt);
SendMessage(session, "连接成功");
}
/**
* 连接关闭调用的方法
*/
@OnClose
public void onClose(Session session) {
SessionSet.remove(session);
int cnt = OnlineCount.decrementAndGet();
System.out.printf("有连接关闭，当前连接数为："+ cnt);
}
/**
* 收到客户端消息后调用的方法
*
* @param message
* 客户端发送过来的消息
*/
@OnMessage
public void onMessage(String message, Session session) {
System.out.printf("来自客户端的消息："+ message);
SendMessage(session, "收到消息，消息内容："+ message);
}
/**
* 出现错误
* @param session
* @param error
*/
@OnError
public void onError(Session session, Throwable error) {
System.out.printf("发生错误：{}，Session ID： {}",error.getMessage(),session.getId());
error.printStackTrace();
}
/**
* 发送消息，实践表明，每次浏览器刷新，session会发生变化。
* @param session
* @param message
*/
public static void SendMessage(Session session, String message) {
try {
session.getBasicRemote().sendText(message);
} catch (IOException e) {
System.out.printf("发送消息出错："+ e.getMessage());
e.printStackTrace();
}
}
/**
* 群发消息
* @param message
* @throws IOException
*/
public static void BroadCastInfo(String message) throws IOException {
for (Session session : SessionSet) {
if(session.isOpen()){
SendMessage(session, message);
}
}
}
/**
* 指定Session发送消息
* @param sessionId
* @param message
* @throws IOException
*/
public static void SendMessage(String message,String sessionId) throws IOException {
Session session = null;
for (Session s : SessionSet) {
if(s.getId().equals(sessionId)){
session = s;
break;
}
}
if(session!=null){
SendMessage(session, message);
}
else{
System.out.printf("没有找到你指定ID的会话："+ sessionId);
}
}
}The third step: on the JS code
<!DOCTYPE html>
<html lang="zh" xmlns:th="http://www.thymeleaf.org" xmlns:shiro="http://www.pollix.at/thymeleaf/shiro">
<head>
<meta charset="UTF-8">
<title>websocket测试</title>
<script src="http://libs.baidu.com/jquery/2.0.0/jquery.min.js"></script>
<style type="text/css">
h3,h4{
text-align:center;
}
</style>
</head>
<body>
<h3>WebSocket测试，客户端接收到的消息如下：</h3>
<textarea id = "messageId" readonly="readonly" cols="150" rows="30" >
</textarea>
<script type="text/javascript">
var socket;
if (typeof (WebSocket) == "undefined") {
console.log("遗憾：您的浏览器不支持WebSocket");
} else {
console.log("恭喜：您的浏览器支持WebSocket");
//实现化WebSocket对象
//指定要连接的服务器地址与端口建立连接
//注意ws、wss使用不同的端口。我使用自签名的证书测试，
//无法使用wss，浏览器打开WebSocket时报错
//ws对应http、wss对应https。
socket = new WebSocket("ws://localhost:8085/project/dealWith");
//连接打开事件
socket.onopen = function() {
console.log("Socket 已打开");
socket.send("消息发送测试(12356)");
};
//收到消息事件
socket.onmessage = function(msg) {
$("#messageId").append(msg.data+ "\n");
console.log(msg.data );
};
//连接关闭事件
socket.onclose = function() {
console.log("Socket已关闭");
};
//发生了错误事件
socket.onerror = function() {
alert("Socket发生了错误");
}
//窗口关闭时，关闭连接
window.unload=function() {
socket.close();
};
}
</script>
</body>
</html>Subsequent supplement: If you use the above code socket to report 404, you can refer to the following method to solve it
When reporting 404, we must first rule out that our project has built-in interception and other restrictions. If there is no problem, springBoot itself will also have a socket 404 problem. How to solve it can refer to the following code. First, we introduce the socker specified dependency, and we cannot use Spring’s own Dependencies, we need to quote separately
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-websocket</artifactId>
<version>1.3.5.RELEASE</version>
</dependency>Import socket configuration
package com.odcchina.fai.config;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.socket.server.standard.ServerEndpointExporter;
@Configuration
public class WebSocketConfig {
@Bean
public ServerEndpointExporter serverEndpointExporter() {
return new ServerEndpointExporter();
}
}Follow the above steps to solve the problem! ! ! ! ! ! ! ! ! ! ! !