spingboot中创建简单的WebSocket服务和使用OKHttp创建socket客户端接收数据

背景

springboot 中使用okhttp3创建webSocket服务端 server1 和客户端
client1，客户端clinet1调用server1用于发送图片，创建客户端client2接收此图片.

在Spring
Boot中使用OkHttp3创建WebSocket服务端和客户端，涉及到两个不同的操作：建立WebSocket服务端和创建WebSocket客户端。OkHttp3库主要用于客户端操作，因此对于服务端，我们将使用Spring的WebSocket支持。

步骤 1: 创建WebSocket服务端（Server1）

添加Spring WebSocket依赖

在pom.xml中添加Spring Boot的WebSocket依赖：

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

配置WebSocket

创建一个配置类来启用WebSocket并注册一个endpoint：

import org.springframework.context.annotation.Configuration;
import org.springframework.messaging.simp.config.MessageBrokerRegistry;
import org.springframework.web.socket.config.annotation.EnableWebSocketMessageBroker;
import org.springframework.web.socket.config.annotation.StompEndpointRegistry;
import org.springframework.web.socket.config.annotation.WebSocketMessageBrokerConfigurer;

@Configuration
@EnableWebSocketMessageBroker
public class WebSocketConfig implements WebSocketMessageBrokerConfigurer {

    @Override
    public void registerStompEndpoints(StompEndpointRegistry registry) {
        registry.addEndpoint("/ws").setAllowedOrigins("*").withSockJS();
    }

    @Override
    public void configureMessageBroker(MessageBrokerRegistry registry) {
        registry.enableSimpleBroker("/topic");
        registry.setApplicationDestinationPrefixes("/app");
    }
}

创建消息处理器

创建一个控制器来处理发送到服务端的消息：

import org.springframework.messaging.handler.annotation.MessageMapping;
import org.springframework.messaging.handler.annotation.SendTo;
import org.springframework.stereotype.Controller;

@Controller
public class ImageMessageController {

    @MessageMapping("/receive-image")
    @SendTo("/topic/image")
    public byte[] receiveImage(byte[] imageData) {
        // 处理接收到的图片数据
        return imageData; // 将图片数据转发到订阅了 /topic/image 的客户端
    }
}

步骤 2: 创建WebSocket客户端（Client1）

添加OkHttp依赖

在pom.xml中添加OkHttp3依赖：

<dependency>
    <groupId>com.squareup.okhttp3</groupId>
    <artifactId>okhttp</artifactId>
    <version>4.9.0</version> <!-- 请使用最新版本 -->
</dependency>

创建WebSocket客户端

创建一个客户端来连接到WebSocket服务端并发送图片：

import okhttp3.OkHttpClient;
import okhttp3.Request;
import okhttp3.WebSocket;
import okhttp3.WebSocketListener;
import okio.ByteString;

public class ImageWebSocketClient extends WebSocketListener {

    private final OkHttpClient client = new OkHttpClient();
    private WebSocket webSocket;

    public void connect(String url) {
        Request request = new Request.Builder().url(url).build();
        webSocket = client.newWebSocket(request, this);
    }

    public void sendImage(byte[] imageData) {
        if (webSocket != null) {
            webSocket.send(ByteString.of(imageData));
        }
    }

    @Override
    public void onOpen(WebSocket webSocket, okhttp3.Response response) {
        super.onOpen(webSocket, response);
        // WebSocket连接成功建立
    }

    @Override
    public void onMessage(WebSocket webSocket, ByteString bytes) {
        super.onMessage(webSocket, bytes);
        // 处理接收到的二进制消息
    }

    @Override
    public void onClosed(WebSocket webSocket, int code, String reason) {
        super.onClosed(webSocket, code, reason);
        // 处理WebSocket关闭事件
    }

    @Override
    public void onFailure(WebSocket webSocket, Throwable t, okhttp3.Response response) {
        super.onFailure(webSocket, t, response);
        // 处理WebSocket连接失败事件
    }

    public void close() {
        if (webSocket != null) {
            webSocket.close(1000, "End of session");
        }
    }
}

步骤 3: 创建另一个客户端（Client2）

创建另一个客户端来接收由Client1发送的图片：

public class ImageReceivingClient extends WebSocketListener {

    private final OkHttpClient client = new OkHttpClient();
    private WebSocket webSocket;

    public void connect(String url) {
        Request request = new Request.Builder().url(url).build();
        webSocket = client.newWebSocket(request, this);
    }

    @Override
    public void onMessage(WebSocket webSocket, ByteString bytes) {
        super.onMessage(webSocket, bytes);
        // 处理接收到的图片数据
        byte[] imageData = bytes.toByteArray();
        // 可以在这里将图片数据保存到文件或进行其他处理
    }

    public void close() {
        if (webSocket != null) {
            webSocket.close(1000, "End of session");
        }
    }
}

步骤 4: 使用客户端

在你的服务中，使用上面创建的ImageWebSocketClient和ImageReceivingClient来发送和接收图片。

public class WebSocketService {

    public void sendImage(String url, byte[] imageData) {
        ImageWebSocketClient client = new ImageWebSocketClient();
        client.connect(url);
        client.sendImage(imageData);
        client.close();
    }

    public void receiveImage(String url) {
        ImageReceivingClient client = new ImageReceivingClient();
        client.connect(url);
        // 保持连接，直到需要断开
    }
}