websocket链接及调试

1.pom文件添加websocket依赖

<!--webSocket依赖-->
<dependency>
   <groupId>org.springframework.boot</groupId>
   <artifactId>spring-boot-starter-websocket</artifactId>
</dependency>
<dependency>
   <groupId>org.apache.tomcat.embed</groupId>
   <artifactId>tomcat-embed-websocket</artifactId>
</dependency>

<dependency>
   <groupId>org.springframework.boot</groupId>
   <artifactId>spring-boot-starter-websocket</artifactId>
   <exclusions>
      <exclusion>
         <groupId>org.springframework.boot</groupId>
         <artifactId>spring-boot-starter-logging</artifactId>
      </exclusion>
   </exclusions>
</dependency>

2.创建WebSocketConfig类文件

package XXX.websocket;

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

3.创建WebSocket文件

package XXX.websocket;

import org.springframework.stereotype.Controller;

import javax.websocket.OnClose;
import javax.websocket.OnMessage;
import javax.websocket.OnOpen;
import javax.websocket.Session;
import javax.websocket.server.PathParam;
import javax.websocket.server.ServerEndpoint;
import java.util.HashMap;
import java.util.Map;
import java.util.concurrent.CopyOnWriteArraySet;

//注意是controller注解
@Controller
@ServerEndpoint("/websocket/{tableId}")
public class WebSocket {
   private Session session;
   public static CopyOnWriteArraySet<WebSocket> webSockets = new CopyOnWriteArraySet<>();
   private static Map<String, Session> sessionPool = new HashMap<String, Session>();

   @OnOpen
   public void onOpen(Session session, @PathParam(value = "tableId") String code) {
      this.session = session;
      webSockets.add(this);
      sessionPool.put(code, session);
      // Constants.WEBSOCKET = true;//定义常量  是否开启websocket连接
      System.out.println("【websocket消息】有新的连接，总数为:" + webSockets.size());
   }

   @OnClose
   public void onClose() {
      webSockets.remove(this);
      //Constants.WEBSOCKET = false;
      System.out.println("【websocket消息】连接断开，总数为:" + webSockets.size());
   }

   @OnMessage
   public void onMessage(String message) {
      System.out.println("【websocket消息】收到客户端消息:" + message);
   }

   // 此为广播消息
   public void sendAllMessage(String message) {
      for (WebSocket webSocket : webSockets) {
         System.out.println("【websocket消息】广播消息:" + message);
         try {
            webSocket.session.getAsyncRemote().sendText(message);
         } catch (Exception e) {
            e.printStackTrace();
         }
      }
   }

   // 此为单点消息
   public void sendOneMessage(String code, String message) {
      Session session = sessionPool.get(code);
      System.out.println(code);
      /*在发送数据之前先确认 session是否已经打开 使用session.isOpen() 为true 则发送消息
       * 不然会报错:The WebSocket session [0] has been closed and no method (apart from close()) may be called on a closed session */
      if (session != null && session.isOpen()) {
         try {
            session.getAsyncRemote().sendText(message);
         } catch (Exception e) {
            e.printStackTrace();
         }
      }
   }
}

4.springBoot启动类上添加注解进行启动

@EnableDiscoveryClient

5.添加推送接口

@Autowired
private WebSocket webSocketServer;


// @Inner(value = false)
@PostMapping("/pushCarWarningInfo")
public R pushCarWarningInfo(String message,String license) {
   webSocketServer.sendAllMessage(message);
   return R.ok(message);

}

6.测试页面html添加socket链接

socket = new WebSocket("ws:127.0.0.1:9003/websocket/12311");

7.打开页面，看是否socket open

8.给接口发送消息，看页面是否正常接收显示