Azure iothub Java SDK on Android

AzureIoT.java

public class AzureIoT
{
    private static final String sServiceHostName        = "...";
    private static final String sServiceSharedAccessKey = "...";
  
    private final Activity mActivity;
    private final ExecutorService mExecutorService;

    public AzureIoT(Activity activity)
    {
        mActivity = activity;
        mExecutorService = Executors.newSingleThreadExecutor();
    }

    private Future<?> runAsyncTask(Runnable task)
    {
        return mExecutorService.submit(task);
    }

    public interface DeviceAddCallback
    {
        void onSuccess(Device device);

        void onException(String deviceId, Exception exception);
    }

    private static String createServiceConnectionString(String hostName, String sharedAccessKey)
    {
        return DeviceClient.HOSTNAME_ATTRIBUTE + hostName +
               ";SharedAccessKeyName=iothubowner" +
               ';' + DeviceClient.SHARED_ACCESS_KEY_ATTRIBUTE + sharedAccessKey;
    }

    private static String createDeviceConnectionString(String hostName, Device device)
    {
        return DeviceClient.HOSTNAME_ATTRIBUTE + hostName +
               ';' + DeviceClient.DEVICE_ID_ATTRIBUTE + device.getDeviceId() +
               ';' + DeviceClient.SHARED_ACCESS_KEY_ATTRIBUTE + device.getPrimaryKey();
    }

    public void deviceAdd(String deviceId, DeviceAddCallback callback)
    {
        runAsyncTask(() -> {

            Device tempDevice;
            Exception tempException;

            try
            {
                String serviceConnectionString = createServiceConnectionString(sServiceHostName, sServiceSharedAccessKey);

                RegistryManager registryManager = RegistryManager.createFromConnectionString(serviceConnectionString);

                tempDevice = Device.createFromId(deviceId, null, null);

                try
                {
                    tempDevice = registryManager.addDevice(tempDevice);
                    tempException = null;
                }
                catch (IotHubException iote)
                {
                    try
                    {
                        tempDevice = registryManager.getDevice(deviceId);
                        tempException = null;
                    }
                    catch (IotHubException iotf)
                    {
                        tempException = iotf;
                    }
                }
            }
            catch (Exception e)
            {
                tempDevice = null;
                tempException = e;
            }

            final Device device = tempDevice;
            final Exception exception = tempException;

            mActivity.runOnUiThread(() -> {
                if (callback != null)
                {
                    if (device != null)
                    {
                        callback.onSuccess(device);
                    }
                    else
                    {
                        callback.onException(deviceId, exception);
                    }
                }
            });
        });
    }

    public interface DeviceSendMessageCallback
    {
        void onSuccess(Device device, DeviceClient deviceClient);

        void onException(Device device, Exception exception);
    }

    public void deviceSendMessage(Device device, String messageText, DeviceSendMessageCallback callback)
    {
        runAsyncTask(() -> {
            DeviceClient tempDeviceClient;
            Exception tempException;

            try
            {
                String connectionString = createIoTDeviceConnectionString(sServiceHostName, device);

                tempDeviceClient = new DeviceClient(connectionString, IotHubClientProtocol.MQTT);

                tempDeviceClient.open();

                Message message = new Message(messageText);
                IotHubEventCallback iotHubEventCallback = (responseStatus, callbackContext) -> {
                    FooLog.i(TAG,
                            "deviceSendMessage: IoT Hub responded to message with status " +
                            responseStatus.name());
                    if (callbackContext != null)
                    {
                        //noinspection SynchronizationOnLocalVariableOrMethodParameter
                        synchronized (callbackContext)
                        {
                            callbackContext.notify();
                        }
                    }
                };
                Object callbackContext = new Object();

                tempDeviceClient.sendEventAsync(message, iotHubEventCallback, callbackContext);

                //noinspection SynchronizationOnLocalVariableOrMethodParameter
                synchronized (callbackContext)
                {
                    try
                    {
                        callbackContext.wait();
                    }
                    catch (InterruptedException e)
                    {
                        // ignore
                    }
                }

                tempException = null;
            }
            catch (Exception e)
            {
                tempDeviceClient = null;
                tempException = e;
            }

            DeviceClient deviceClient = tempDeviceClient;
            Exception exception = tempException;

            mActivity.runOnUiThread(() -> {
                if (callback != null)
                {
                    if (deviceClient != null)
                    {
                        callback.onSuccess(device, deviceClient);
                    }
                    else
                    {
                        callback.onException(device, exception);
                    }
                }
            });

            if (deviceClient != null)
            {
                try
                {
                    deviceClient.close();
                }
                catch (IOException e)
                {
                    // ignore
                }
            }
        });
    }
}

Caller.java

mAzureIoT = new AzureIoT(this);

String deviceId = "qwigybo";

mAzureIoT.deviceAdd(deviceId, new IoTDeviceAddCallback()
{
    @Override
    public void onSuccess(Device device)
    {
        FooLog.i(TAG, "deviceAdd onSuccess: device id=" + device.getDeviceId());
        FooLog.i(TAG, "deviceAdd onSuccess: device primaryKey=" + device.getPrimaryKey());

        String message = "w00t @ " + new Date().toString();
        mAzureIoT.deviceSendMessage(device, message, new IoTDeviceSendMessageCallback()
        {
            @Override
            public void onSuccess(Device device, DeviceClient deviceClient)
            {
                FooLog.i(TAG, "deviceSendMessage onSuccess: device id=" + device.getDeviceId());
            }

            @Override
            public void onException(Device device, Exception exception)
            {
                FooLog.e(TAG, "deviceSendMessage onException: device id=" + deviceId, exception);
            }
        });
    }

    @Override
    public void onException(String deviceId, Exception exception)
    {
        FooLog.e(TAG, "deviceAdd onException: device id=" + deviceId, exception);
    }
});