Android 浅析 okHttp WebSocket (一) 使用

前言

Linus Benedict Torvalds : RTFSC – Read The Funning Source Code

概括

okHttp 对于大家来说已经不再陌生了，使用起来也是非常的方便，本章开始将介绍利用 okHttp 进行 WebSocket 的使用。

本章的程序所使用的客户端和服务端皆出自okhttp，okhttp自带一套模仿服务端的操作。

使用

Step 1：构建服务端

// 创建全局对象 MockWebServer
private static final MockWebServer mMockWebServer = new MockWebServer();
// 创建对象 服务端响应对象
private MockResponse mMockResponse = null;

// 创建监听回调
public MockResponse createResponse() {
    return new MockResponse().withWebSocketUpgrade(new WebSocketListener() {
        @Override
        public void onOpen(WebSocket webSocket, Response response) {
            System.out.println("server onOpen: request header:" + response.request().headers() + " response header:" + response.headers() + " response:" + response);
        }
    
        @Override
        public void onMessage(WebSocket webSocket, String string) {
            System.out.println("server onMessage: message:" + string);
        }
    
        @Override
        public void onClosing(WebSocket webSocket, int code, String reason) {
            System.out.println("server onClosing: code:" + code + " reason:" + reason);
        }
    
        @Override
        public void onClosed(WebSocket webSocket, int code, String reason) {
            System.out.println("server onClosed code:" + code + " reason:" + reason);
        }
    
        @Override
        public void onFailure(WebSocket webSocket, Throwable t, Response response) {
            System.out.println("server onFailure");
        }
    });
}

private void initMockServer() {
    mMockResponse = createResponse();
    mMockWebServer.enqueue(mMockResponse);
}

MockServer：okhttp提供的一个虚拟服务端类。可编写脚本的Web服务器。调用者提供固定响应，服务器按请求重新播放它们。

Step 2：构建客户端

// 新建client
private static final OkHttpClient mClient = new OkHttpClient.Builder().build();

// 创建请求回调
private WebSocketListener createListener() {
	return new WebSocketListener() {
        @Override
        public void onOpen(WebSocket webSocket, Response response) {
            mWebSocket = webSocket;
            System.out.println("client onOpen");
            System.out.println("client request header:" + response.request().headers());
            System.out.println("client response header:" + response.headers());
            System.out.println("client response:" + response);
        }

        @Override
        public void onMessage(WebSocket webSocket, String text) {
            System.out.println("client onMessage");
            System.out.println("message:" + text);
        }

        @Override
        public void onMessage(WebSocket webSocket, ByteString bytes) {
        }

        @Override
        public void onClosing(WebSocket webSocket, int code, String reason) {
            System.out.println("client onClosing");
            System.out.println("code:" + code + " reason:" + reason);
        }

        @Override
        public void onClosed(WebSocket webSocket, int code, String reason) {
            System.out.println("client onClosed");
            System.out.println("code:" + code + " reason:" + reason);
        }

        @Override
        public void onFailure(WebSocket webSocket, Throwable t, Response response) {
            System.out.println("client onFailure");
        }
    }
}

private static void initWsClient(String wsUrl) {
    Request request = new Request.Builder().url(wsUrl).build();
    WebSocketListener wbListener = createListener();
    mClient.newWebSocket(request, wbListener);
}

Step 3：创建线程调用

new Thread(new Runnable() {
    @Override
    public void run() {
        initMockServer();
        initWsClient("ws://" + mMockWebServer.getHostName() + ":" + mMockWebServer.getPort() + "/");
    }
}).start();

这样就完成了整个简单的调用流程。
完成了流程后我们就可以在应答中通过WebSocket的send(String text)将需要的信息发送给服务端或者客户端。

总结

简单的使用很容易就完成了，在使用的途中okhttp已经帮我们完成了虚拟的服务端构建，在接下来的章节会继续做深入的分析。