Java实现WebSocket客户端详细步骤

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

import org.java_websocket.client.WebSocketClient;
import org.java_websocket.handshake.ServerHandshake;
import org.java_websocket.websocketexception.WebSocketException;
import java.net.URI;

public class MyWebSocketClient extends WebSocketClient {

    public MyWebSocketClient(URI serverUri) {
        super(serverUri);
    }

    @Override
    public void onOpen(ServerHandshake handShake) throws WebSocketException {
        System.out.println("连接已建立");
        // 连接成功后可以发送初始消息
        send("Hello, Server!");
    }

    @Override
    public void onMessage(String message) {
        System.out.println("收到消息: " + message);
        // 根据需要处理接收到的消息
    }

    @Override
    public void onClose(int code, String reason, boolean remote) {
        System.out.println("连接已关闭，代码: " + code + ", 原因: " + reason);
    }

    @Override
    public void onError(Exception ex) {
        System.out.println("发生错误: " + ex.getMessage());
        ex.printStackTrace();
    }
}

import org.java_websocket.client.WebSocketClient;
import java.net.URI;

public class WebSocketMain {

    public static void main(String[] args) {
        try {
            // 替换为你实际的WebSocket服务器地址
            URI serverUri = new URI("ws://echo.websocket.org");
            MyWebSocketClient client = new MyWebSocketClient(serverUri);

            // 连接成功时会调用onOpen方法
            client.connect();

            // 保持主线程运行，以便接收消息
            Thread.sleep(10000); // 等待10秒后自动关闭连接

            // 关闭连接
            client.close();
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}

连接已建立
收到消息: Hello, Server!

@Override
public void onMessage(String message) {
    System.out.println("收到消息: " + message);
    
    // 解析JSON消息
    try {
        JSONObject jsonObject = new JSONObject(message);
        String command = jsonObject.getString("command");
        
        switch (command) {
            case "echo":
                send("Echo received: " + jsonObject.getString("data"));
                break;
            case "disconnect":
                close();
                break;
            default:
                System.out.println("未知命令");
        }
    } catch (JSONException e) {
        e.printStackTrace();
    }
}

@Override
public void onOpen(ServerHandshake handShake) throws WebSocketException {
    System.out.println("连接已建立");
    
    // 发送初始消息
    send("Hello, Server!");
    
    // 启动心跳线程
    new Thread(() -> {
        while (client.isOpen()) {
            try {
                // 每10秒发送一次心跳
                Thread.sleep(10000);
                send("heartbeat");
            } catch (InterruptedException e) {
                break;
            }
        }
    }).start();
}

@Override
public void onClose(int code, String reason, boolean remote) {
    System.out.println("连接已关闭，代码: " + code + ", 原因: " + reason);
    
    // 尝试重新连接
    new Thread(() -> {
        try {
            client.reconnectBlocking();
            System.out.println("成功重新连接");
        } catch (WebSocketException e) {
            e.printStackTrace();
        }
    }).start();
}

@Override
public void onError(Exception ex) {
    System.out.println("发生错误: " + ex.getMessage());
    ex.printStackTrace();
    
    // 关闭连接并尝试重新连接
    close();
}

import java.util.concurrent.ConcurrentLinkedQueue;

public class MyWebSocketClient extends WebSocketClient {

    private ConcurrentLinkedQueue<String> messageQueue = new ConcurrentLinkedQueue<>();

    public MyWebSocketClient(URI serverUri) {
        super(serverUri);
    }

    @Override
    public void onMessage(String message) {
        System.out.println("收到消息: " + message);
        messageQueue.add(message);
        
        // 启动一个线程处理队列中的消息
        new Thread(() -> processMessages()).start();
    }

    private void processMessages() {
        while (!messageQueue.isEmpty()) {
            String message = messageQueue.poll();
            // 处理消息的逻辑
            System.out.println("正在处理: " + message);
        }
    }
}