java WebSocket服务端

使用java中Java-WebSocket做服务端

pom文件

<!-- 实际使用包 -->
<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-web</artifactId>
</dependency>

<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-websocket</artifactId>
</dependency>
<!--websocket作为客户端-->
<dependency>
    <groupId>org.java-websocket</groupId>
    <artifactId>Java-WebSocket</artifactId>
    <version>1.3.5</version>
</dependency>

服务端实现

package com.xie.websocket;

import com.alibaba.fastjson.JSONObject;
import lombok.extern.slf4j.Slf4j;
import org.springframework.stereotype.Component;

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.io.IOException;
import java.util.List;
import java.util.Map;
import java.util.concurrent.CopyOnWriteArraySet;

/**
 * @Description
 * @Date 2022-04-01 11:28
 * @Author xie
 */
@Slf4j
@Component
@ServerEndpoint(value = "/ws/data/{param}")
public class WebSocketServer {

    //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<WebSocketServer> 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;

    // 业务service
    private TestService testService = (TestService) ApplicationContextHandle.getBean(TestService.class);

    /**
     * 连接建立成功调用的方法
     */
    @OnOpen
    public void onOpen(Session session, @PathParam("param") String param) {
        this.session = session;   //加入set中
        webSocketSet.add(this);
        try {
            while (true) {
                // 处理数据并发送
                List<Map<String, Object>> result = testService.findDataByParam(param);
                sendMessage(JSONObject.toJSONString(result));
                Thread.sleep(3000);
            }
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    /**
     * 连接关闭调用的方法
     */
    @OnClose
    public void onClose() {
        webSocketSet.remove(this);  //从set中删除
    }

    /**
     * 收到客户端消息后调用的方法
     */
    @OnMessage
    public void onMessage(String message, Session session) {
        log.info("收到客户端的消息:{}", message);
    }

    /**
     * 发生错误时调用
     */
    public void onError(Session session, Throwable error) {
        error.printStackTrace();
    }

    /**
     * 发送消息
     */
    public void sendMessage(String message) throws IOException {
        this.session.getAsyncRemote().sendText(message);
    }


    /**
     * 群发自定义消息
     */
    public static void sendInfo(String message) throws IOException {
        for (WebSocketServer item : webSocketSet) {
            try {
                item.sendMessage(message);
            } catch (IOException e) {
                e.printStackTrace();
                continue;
            }
        }
    }
}