18

我创建了一个client类型MqttClient,如下面的代码所示,我创建了一个客户端并设置了它的Asynchronous callback. 问题是,

1-当我运行程序时,System.out.println("Client is Connected");出现了,但我没有收到onSuccess来自 o 或 o的响应onFailure,为什么?我在代码中做错了什么。

2-我实现了static IMqttAsyncClient asynchClientCB = new IMqttAsyncClient()接口,但由于我有一个类型的客户端MqttClient,我不能使用这个IMqttAsyncClient接口。我尝试使用mqttAsynchClien,但因为我为 java 编程而不是因为Android我不能使用它。如何使用IMqttAsyncClient界面。?

更新_1

在下面的代码“Updated_code_1”中,我稍微修改了代码,但我希望每次成功连接到同步回调中broker​​的消息时都会打印出来,并且在连接终止的情况下打印同步回调中​​的消息,例如当我故意断开网络时。但是在我连接到的时候,既不也不显示任何东西。那么,它们的设计目的是什么?onSuccessonFailurebrokeronSuccessonFailur

*Update_2_17_Dec_2014

我有一个询问可能会引导我们找到解决方案,也就是说,我通过有线/无线网络连接到代理是否重要?这会改变同步和异步监听器的行为吗?

更新_1_code

MqttConnectOptions opts = getClientOptions();
        client = MQTTClientFactory.newClient(broker, port, clientID);

        if (client != null) {
            System.out.println("Client is not Null");
            client.setCallback(AsynchCallBack);
            if (opts != null) {
                iMQTTToken = client.connectWithResult(opts);
                publishMSG(client, TOPIC,"010101".getBytes(), QoS, pub_isRetained);
                iMQTTToken.setActionCallback(synchCallBack);
                if (client.isConnected()) {
                    System.out.println("Client CONNECTED.");
                    publishMSG(client, TOPIC,"010101".getBytes(), QoS, pub_isRetained);
                }
            }
        }
    ....
    ....
    ....
    ....
IMqttToken iMQTTToken = new IMqttToken() {

    @Override
    public void waitForCompletion(long arg0) throws MqttException {
        // TODO Auto-generated method stub
        System.out.println("@waitForCompletion(): waiting " + (arg0 * 1000) + " seconds for connection to be established.");
    }

    @Override
    public void waitForCompletion() throws MqttException {
        // TODO Auto-generated method stub
        System.out.println("@waitForCompletion(): waiting for connection to be established.");
    }

    @Override
    public void setUserContext(Object arg0) {
        // TODO Auto-generated method stub

    }

    @Override
    public void setActionCallback(IMqttActionListener arg0) {
        // TODO Auto-generated method stub
        arg0.onSuccess(iMQTTToken);
        //System.out.println(" " + arg0.onSuccess());
        //System.out.println(" " + arg0.onSuccess(iMQTTToken));
        iMQTTToken.setActionCallback(synchCallBack);
    }

    @Override
    public boolean isComplete() {
        // TODO Auto-generated method stub
        return false;
    }

    @Override
    public Object getUserContext() {
        // TODO Auto-generated method stub
        return null;
    }

    @Override
    public String[] getTopics() {
        // TODO Auto-generated method stub
        return null;
    }

    @Override
    public boolean getSessionPresent() {
        // TODO Auto-generated method stub
        return false;
    }

    @Override
    public MqttWireMessage getResponse() {
        // TODO Auto-generated method stub
        return null;
    }

    @Override
    public int getMessageId() {
        // TODO Auto-generated method stub
        return 0;
    }

    @Override
    public int[] getGrantedQos() {
        // TODO Auto-generated method stub
        return null;
    }

    @Override
    public MqttException getException() {
        // TODO Auto-generated method stub
        return null;
    }

    @Override
    public IMqttAsyncClient getClient() {
        // TODO Auto-generated method stub
        return null;
    }

    @Override
    public IMqttActionListener getActionCallback() {
        // TODO Auto-generated method stub
        return null;
    }
};

IMqttActionListener synchCallBack = new IMqttActionListener() {

    @Override
    public void onSuccess(IMqttToken arg0) {
        // TODO Auto-generated method stub
        System.out.println("@onSuccess: Connection Successful.");
    }

    @Override
    public void onFailure(IMqttToken arg0, Throwable arg1) {
        // TODO Auto-generated method stub
        System.out.println("@onFailure: Connection Failed.");
        setViewEnableState(Bconnect, true);
    }
};

MqttCallback AsynchCallBack = new MqttCallback() {

    @Override
    public void messageArrived(String topic, MqttMessage msg) throws Exception {
        // TODO Auto-generated method stub
        System.out.println("@messageArrived: Message Delivered.");
    }

    @Override
    public void deliveryComplete(IMqttDeliveryToken token) {
        // TODO Auto-generated method stub
        System.out.println("@deliveryComplete: Delivery Completed.");
    }

    @Override
    public void connectionLost(Throwable thrw) {
        // TODO Auto-generated method stub
        System.out.println("@Connection Lost: Connection Lost.");
        setViewEnableState(Bconnect, true);
    }
};

新客户

    MqttConnectOptions opts = new MqttConnectOptions();
    opts.setCleanSession(CS);
    opts.setKeepAliveInterval(KATimer);
    HashMap<Integer, WILL> LWTData = WILLFactory.newWILL("LWT", "LWT MS".getBytes(), 1, false);
    opts.setWill(LWTData.get(0).getWILLTopic(), 
            LWTData.get(0).getWILLPayLoad(), 
            LWTData.get(0).getWILLQoS(), 
            LWTData.get(0).isWILLRetained());

    client = MQTTClientFactory.newClient(IP, PORT, clientID);

    if (client != null) {
        System.out.println("client is not null");

        client.setCallback(AsynchCB);
        IMqttToken token = client.connectWithResult(opts);

        if (client.isConnected()) {
            System.out.println("Client is Connected");

            token.setActionCallback(new IMqttActionListener() {

                public void onSuccess(IMqttToken arg0) {
                    // TODO Auto-generated method stub
                    System.out.println("synchCB->@onSuccess(): Connection Successful");

                    try {
                        client.subscribe(TOPIC, QoS);
                    } catch (MqttException e) {
                        // TODO Auto-generated catch block
                        e.printStackTrace();
                    }
                    try {
                        client.disconnect();
                    } catch (MqttException e) {
                        // TODO Auto-generated catch block
                        e.printStackTrace();
                    }
                }

                public void onFailure(IMqttToken arg0, Throwable arg1) {
                    // TODO Auto-generated method stub
                    System.out.println("synchCB->@onFailure(): Connection Failed");
                }
            });
        }else {
            System.out.println("client is not connected");
        }
    }else {
        System.out.println("client = null");
    }

异步回调

/**
 * Asynchronous Callback to inform the user about events that might happens Asynchronously. If it is not used, any pending 
 * messages destined to the client would not be received.
 */
private static MqttCallback AsynchCB = new MqttCallback() {

    public void messageArrived(String topic, MqttMessage msg) throws Exception {
        // TODO Auto-generated method stub
        System.out.println("AsynchCB->@messageArrived(): ");

        System.out.println("Topic: " + topic);
        System.out.println("MSG: " + msg.toString());

    }

    public void deliveryComplete(IMqttDeliveryToken arg0) {
        // TODO Auto-generated method stub
        System.out.println("AsynchCB->@deliveryComplete(): ");
    }

    public void connectionLost(Throwable arg0) {
        // TODO Auto-generated method stub
        System.out.println("AsynchCB->@connectionLost(): ");
    }
};
4

2 回答 2

2

处理您的回调的客户端所在的计算机可能具有被计算机防火墙阻止的传出端口。

于 2014-12-11T15:55:29.757 回答
0

如果上一个循环中的连接没有成功断开,那么再次尝试连接将不会提供任何响应。即,如果为已连接的客户端调用连接,则它不会产生任何响应。

于 2021-08-10T05:36:37.063 回答