加入依赖
org.springframework.boot
spring-boot-starter-websocket
新建一个WebSocketConfig.java文件
package com.example.demo.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();
}
}
新建一个 WebSocketController.java文件
package com.example.demo.controller;
import org.springframework.stereotype.Component;
import javax.websocket.*;
import javax.websocket.server.ServerEndpoint;
import java.io.IOException;
import java.util.concurrent.CopyOnWriteArraySet;
@ServerEndpoint("/websocket")
@Component
public class WebsocketController {
private static int onlineCount = 0;
private static CopyOnWriteArraySet webSocketSet = new CopyOnWriteArraySet();
private Session session;
/**
* 成功建立连接调用
*/
@OnOpen
public void onOpen(Session session){
this.session = session;
webSocketSet.add(this);
addOnlineCount();
System.out.println("有用户加入直播间，当前在线人数为" + getOnlineCount());
}
/**
* 连接关闭调用的方法
*/
@OnClose
public void onClose(){
webSocketSet.remove(this); //删除连接
subOnlineCount(); //在线人数减1
System.out.println("有人退出直播，当前在线人数为" + getOnlineCount());
}
/**
* 收到客户端消息后调用的方法
*/
@OnMessage
public void onMessage(String message, Session session) {
System.out.println("来自客户端的消息:" + message);
//群发消息
for(WebsocketTest item: webSocketSet){
try {
item.sendMessage(message);
} catch (IOException e) {
e.printStackTrace();
continue;
}
}
}
/**
* 发生错误时调用
*/
@OnError
public void onError(Session session, Throwable error){
System.out.println("发生错误");
error.printStackTrace();
}
public static synchronized int getOnlineCount() {
return onlineCount;
}
public static synchronized void addOnlineCount() {
WebsocketTest.onlineCount++;
}
public static synchronized void subOnlineCount() {
WebsocketTest.onlineCount--;
}
}