4

使用 Ning 创建并连接到 Websocket，以下是我的配置，

 NettyAsyncHttpProviderConfig config = new NettyAsyncHttpProviderConfig();
 config.addProperty(NettyAsyncHttpProviderConfig.USE_BLOCKING_IO, "true");

 AsyncHttpClientConfig.Builder builder = new AsyncHttpClientConfig.Builder()
                .setAsyncHttpClientProviderConfig(config);

 AsyncHttpClient client = new AsyncHttpClient(
                new NettyAsyncHttpProvider(builder.build()));

 AsyncHttpClient.BoundRequestBuilder requestBuilder = client.prepareGet(createUri(method))
                .addHeader(HttpHeaders.Names.CONNECTION, "Upgrade")
                .addHeader(HttpHeaders.Names.UPGRADE, "WebSocket");

 websocket = requestBuilder.execute(new WebSocketUpgradeHandler.Builder()
                .addWebSocketListener(this).build()).get();

使用 websocket 发送短信，

 if (websocket!=null && websocket.isOpen())
       websocket.sendTextMessage(jObj.toString());// send

onMessage()侦听器的方法会将响应添加到列表中

@Override
public void onMessage(String message) {
   serverResponse.add(message);
}

发送短信后，我有格式化响应并保存结果的方法

result = responseFromServer();

private String responseFromServer() {
    String response = null;
    sleep(100);
   if(!serverResponse.isEmpty())
      //format the message which is added in list
    return response;
}

问题是，如果我在上述方法中没有'sleep(100)'，对于request1-响应为空，对于request2，我得到response1。我希望 websocket 能够同步工作，这样，一旦我发送消息，它应该等待单元格接收到响应并继续前进！有什么建议么！

4

2 回答 2

6

在一个物体上使用wait和，notify

synchronized (someObject){
  try {
     someObject.wait();
     result = responseFromServer();
   } catch (InterruptedException e) {
        //when the object is interrupted
   }
}

并在onMessage收到消息后通知对象，

@Override
public void onMessage(String message) {
     serverResponse.add(message);
     synchronized(someObject) {
          someObject.notify();
     }
}
于 2014-09-29T18:31:24.977 回答
3

您还可以使用 CountDownLatch 概念，如下面的链接所示： 

@ClientEndpoint
public class WordgameClientEndpoint {

    private static CountDownLatch latch;

    private Logger logger = Logger.getLogger(this.getClass().getName());

    @OnOpen
    public void onOpen(Session session) {
        // same as above
    }

    @OnMessage
    public String onMessage(String message, Session session) {
        // same as above
    }

    @OnClose
    public void onClose(Session session, CloseReason closeReason) {
        logger.info(String.format("Session %s close because of %s", session.getId(), closeReason));
        latch.countDown();
    }

    public static void main(String[] args) {
        latch = new CountDownLatch(1);

        ClientManager client = ClientManager.createClient();
        try {
            client.connectToServer(WordgameClientEndpoint.class, new URI("ws://localhost:8025/websockets/game"));
            latch.await();

        } catch (DeploymentException | URISyntaxException | InterruptedException e) {
            throw new RuntimeException(e);
        }
    }
}

https://blog.openshift.com/how-to-build-java-websocket-applications-using-the-jsr-356-api/

于 2017-10-10T19:06:11.490 回答