Spring Boot WebSocket

1. SpringBoot2对WebSocket的支持很赞

 
org.springframework.boot
spring-boot-starter-websocket

2. WebSocketConfig

  package com.springboot.websocket.config;
  import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.Configuration;
 importorg.springframework.web.socket.server.standard.ServerEndpointExporter;
@Configuration
public class WebSocketConfig {
@Bean
public ServerEndpointExporter serverEndpointExporter() {
    return new ServerEndpointExporter();
  }
  }

3.WebSocketServer

  因为WebSocket是类似客户端服务端的形式(采用ws协议)，那么这里 
的WebSocketServer其实就相当于一个ws协议的Controller 
 直接@ServerEndpoint(“/websocket”)@Component启用即可，然后在 
里面实现@OnOpen,@onClose,@onMessage等方法 
package com.springboot.websocket.config;
 import java.io.IOException;
 import java.util.concurrent.CopyOnWriteArraySet;
  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 org.springframework.stereotype.Component;
  @ServerEndpoint("/websocket")
  @Component
  public class WebSocketServer {
//静态变量，用来记录当前在线连接数。应该把它设计成线程安全的。
private static int onlineCount = 0;
//concurrent包的线程安全Set，用来存放每个客户端对应的MyWebSocket对象。
private static CopyOnWriteArraySet webSocketSet = new CopyOnWriteArraySet();

//与某个客户端的连接会话，需要通过它来给客户端发送数据
private Session session;


/**
 * 连接建立成功调用的方法
 */
@OnOpen
public void onOpen(Session session) {
    this.session = session;
    webSocketSet.add(this);     //加入set中
    addOnlineCount();           //在线数加1
    System.out.println("有新窗口开始监听,当前在线人数为" + getOnlineCount());
    try {
        sendMessage("连接成功");
    } catch (IOException e) {
        System.out.println("WebSocket IO异常");
    }
}

/**
 * 连接关闭调用的方法
 */
@OnClose
public void onClose() {
    webSocketSet.remove(this);  //从set中删除
    subOnlineCount();           //在线数减1
    System.out.println("有连接关闭！当前在线人数为" + getOnlineCount());
}

/**
 * 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.println("收到客户端的信息:" + message);
    //群发消息
    for (WebSocketServer item : webSocketSet) {
        try {
            item.sendMessage(message);
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}

/**
 * @param session
 * @param error
 */
@OnError
public void onError(Session session, Throwable error) {
    System.out.println("发生错误");
    error.printStackTrace();
}

/**
 * 实现服务器主动推送
 */
public void sendMessage(String message) throws IOException {
    this.session.getBasicRemote().sendText(message);
}


/**
 * 群发自定义消息
 */
public static void sendInfo(String message) throws IOException {
    System.out.println("推送消息内容:" + message);
    for (WebSocketServer item : webSocketSet) {
        try {
            item.sendMessage(message);
        } catch (IOException e) {
            continue;
        }
    }
}

public static synchronized int getOnlineCount() {
    return onlineCount;
}

public static synchronized void addOnlineCount() {
    WebSocketServer.onlineCount++;
}

public static synchronized void subOnlineCount() {
    WebSocketServer.onlineCount--;
}

}

4.WebSocketController

  package com.springboot.websocket.controller;
  import com.springboot.websocket.config.WebSocketServer;
import org.springframework.web.bind.annotation.*;
import java.io.IOException;
@RestController
  public class WebSocketController {
//推送数据接口    @RequestMapping("/socket/push")
public String pushMsg(String message) {
    try {
        WebSocketServer.sendInfo(message);
    } catch (IOException e) {
        e.printStackTrace();
    }
    return "success";
}
}

5.index.html

  
  
  


  

WebSocket
  

6. 运行截图

image