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

package com.lby.websocket.config;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.socket.server.standard.ServerEndpointExporter;
/**
 * @author Liby
 * @date 2022-04-25 16:18
 * @description:
 * @version:
 */
@Configuration
public class WebSocketConfig {
    @Bean
    public ServerEndpointExporter serverEndpointExporter() {
        return new ServerEndpointExporter();
    }
}
 

package org.example.server;
import cn.hutool.core.util.StrUtil;
import cn.hutool.json.JSONObject;
import org.apache.logging.log4j.LogManager;
import org.apache.logging.log4j.Logger;
import org.springframework.stereotype.Component;
import javax.websocket.*;
import javax.websocket.server.PathParam;
import javax.websocket.server.ServerEndpoint;
import java.io.IOException;
import java.util.concurrent.ConcurrentHashMap;
/*
啟動(dòng)項(xiàng)目后可通過(guò) http://websocket.jsonin.com/ 進(jìn)行測(cè)試
輸入網(wǎng)址ws://localhost:8080/websocket/1211，檢測(cè)是否能進(jìn)行連接
 */
@ServerEndpoint(value = "/websocket/{userId}")
@Component
public class WebSocket {
    private final static Logger logger = LogManager.getLogger(WebSocket.class);
    /**
     * 靜態(tài)變量，用來(lái)記錄當(dāng)前在線連接數(shù)。應(yīng)該把它設(shè)計(jì)成線程安全的
     */
    private static int onlineCount = 0;
    /**
     * concurrent包的線程安全Map，用來(lái)存放每個(gè)客戶端對(duì)應(yīng)的MyWebSocket對(duì)象
     */
    private static ConcurrentHashMap<String, WebSocket> webSocketMap = new ConcurrentHashMap<>();
    /**
     * 與某個(gè)客戶端的連接會(huì)話，需要通過(guò)它來(lái)給客戶端發(fā)送數(shù)據(jù)
     */
    private Session session;
    private String userId;
    /**
     * 連接建立成功調(diào)用的方法
     */
    @OnOpen
    public void onOpen(Session session, @PathParam("userId") String userId) {
        this.session = session;
        this.userId = userId;
        //加入map
        webSocketMap.put(userId, this);
        addOnlineCount();           //在線數(shù)加1
        logger.info("用戶{}連接成功,當(dāng)前在線人數(shù)為{}", userId, getOnlineCount());
        try {
            sendMessage(String.valueOf(this.session.getQueryString()));
        } catch (IOException e) {
            logger.error("IO異常");
        }
    }
    /**
     * 連接關(guān)閉調(diào)用的方法
     */
    @OnClose
    public void onClose() {
        //從map中刪除
        webSocketMap.remove(userId);
        subOnlineCount();           //在線數(shù)減1
        logger.info("用戶{}關(guān)閉連接！當(dāng)前在線人數(shù)為{}", userId, getOnlineCount());
    }
    /**
     * 收到客戶端消息后調(diào)用的方法
     *
     * @param message 客戶端發(fā)送過(guò)來(lái)的消息
     */
    @OnMessage
    public void onMessage(String message, Session session) {
        logger.info("來(lái)自客戶端用戶：{} 消息:{}",userId, message);
        //群發(fā)消息
        for (String item : webSocketMap.keySet()) {
            try {
                webSocketMap.get(item).sendMessage(message);
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    }
    /**
     * 發(fā)生錯(cuò)誤時(shí)調(diào)用
     *
     */
    @OnError
    public void onError(Session session, Throwable error) {
        logger.error("用戶錯(cuò)誤:" + this.userId + ",原因:" + error.getMessage());
        error.printStackTrace();
    }
    /**
     * 向客戶端發(fā)送消息
     */
    public void sendMessage(String message) throws IOException {
        this.session.getBasicRemote().sendText(message);
        //this.session.getAsyncRemote().sendText(message);
    }
    /**
     * 通過(guò)userId向客戶端發(fā)送消息
     */
    public void sendMessageByUserId(String userId, String message) throws IOException {
        logger.info("服務(wù)端發(fā)送消息到{},消息：{}",userId,message);
        if(StrUtil.isNotBlank(userId)&&webSocketMap.containsKey(userId)){
            webSocketMap.get(userId).sendMessage("hello");
        }else{
            logger.error("用戶{}不在線",userId);
        }
    }
    /**
     * 群發(fā)自定義消息
     */
    public void sendInfo(String message) throws IOException {
        for (String item : webSocketMap.keySet()) {
            try {
                webSocketMap.get(item).sendMessage(message);
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    }
    public static synchronized int getOnlineCount() {
        return onlineCount;
    }
    public static synchronized void addOnlineCount() {
        WebSocket.onlineCount++;
    }
    public static synchronized void subOnlineCount() {
        WebSocket.onlineCount--;
    }
}
 

        <dependency>
            <groupId>org.java-websocket</groupId>
            <artifactId>Java-WebSocket</artifactId>
            <version>1.5.3</version>
        </dependency>

package org.example;
import lombok.SneakyThrows;
import lombok.extern.slf4j.Slf4j;
import org.java_websocket.client.WebSocketClient;
import org.java_websocket.handshake.ServerHandshake;
import java.net.URI;
import java.util.concurrent.Executors;
import java.util.concurrent.ScheduledExecutorService;
import java.util.concurrent.TimeUnit;
/**
 * @author kele
 * @date 2024/2/19
 **/
@Slf4j
public class MyWebSocketClient extends WebSocketClient {
    public MyWebSocketClient(URI serverUri) {
        super(serverUri);
    }
    @SneakyThrows
    @Override
    public void onOpen(ServerHandshake data) {
        try {
            log.info("WebSocket連接已打開。");
        }catch (Exception e){
            log.error("onOpen error :{}",e.getMessage());
        }
    }
    @SneakyThrows
    @Override
    public void onMessage(String message) {
        try {
            if (message != null && !message.isEmpty()) {
                log.info("收到消息: {}",message);
            }
        }catch (Exception e){
            log.error("onMessage error : {}",message);
        }
    }
    @Override
    public void onClose(int code, String reason, boolean remote) {
        log.info("WebSocket連接已關(guān)閉。");
    }
    @Override
    public void onError(Exception ex) {
        log.info("WebSocket連接發(fā)生錯(cuò)誤:{}", ex.getMessage());
    }
    /**
     * 連接定時(shí)檢查
     */
    public void startReconnectTask(long delay, TimeUnit unit) {
        System.out.println("WebSocket 心跳檢查");
        log.info("WebSocket 心跳檢查");
        // 以下為定時(shí)器,建議使用自定義線程池，或交給框架處理（spring）
        ScheduledExecutorService executorService = Executors.newSingleThreadScheduledExecutor();
        executorService.scheduleWithFixedDelay(() -> {
            // 檢查邏輯：判斷當(dāng)前連接是否連通
            if (!this.isOpen()) {
                System.out.println("WebSocket 開始重連......");
                log.info("WebSocket 開始重連......");
                // 重置連接
                this.reconnect();
                // 以下為錯(cuò)誤示范
                //this.close();
                //this.connect();
            }
        }, 0, delay, unit);
    }
}

package org.example;
import lombok.extern.slf4j.Slf4j;
import org.springframework.stereotype.Component;
import javax.annotation.PostConstruct;
import java.net.URI;
import java.util.concurrent.TimeUnit;
@Slf4j
@Component
public class Init implements Runnable {
    public static MyWebSocketClient myWebSocketClient;
    @PostConstruct
    public void run () {
        try {
            //啟動(dòng)連接
            log.info("連接websocket服務(wù)端");
            log.info("項(xiàng)目啟動(dòng)");
            // 服務(wù)地址
            URI uri = new URI("ws://127.0.0.1:8077/websocket/123");
            log.info("服務(wù)地址 -{}", uri);
            // 創(chuàng)建客戶端
            myWebSocketClient = new MyWebSocketClient(uri);
            // 建立連接
            myWebSocketClient.connect();
            // 開啟 定時(shí)檢查
            myWebSocketClient.startReconnectTask(5, TimeUnit.SECONDS);
        }catch (Exception e){
            e.printStackTrace();
        }
    }
}

@OnMessage(maxMessageSize = 10240000)
public void onMessage(byte[] message) throws IOException {
    log.info("收到圖片了");
    String str = Base64.encodeBase64String(message); // 圖片base64
    log.info(str.substring(0, 100));
}