How to detect “Connection refused” when using MqttAsyncClient with no automatic reconnect?

[paho0.txt](https://github.com/eclipse/paho.mqtt.java/files/830222/paho0.txt)

Good morning!

I am using Eclipse Paho Java Client **version 1.1.0** to connect. Here is my extended callback:

```
protected IMqttAsyncClient mClient;

private final MqttCallbackExtended mCallback = new MqttCallbackExtended() {
@Override
public void connectComplete(boolean reconnect, String brokerAddress) {
Log.d(mLogTag, "connectComplete " + brokerAddress);
}

@Override
public void connectionLost(Throwable ex) {
Log.d(mLogTag, "connectionLost", ex);
}

@Override
public void deliveryComplete(IMqttDeliveryToken deliveryToken) {
Log.d(mLogTag, "deliveryComplete " + deliveryToken);
}

@Override
public void messageArrived(String topic, MqttMessage mqttMessage) throws Exception {
Log.d(mLogTag, "messageArrived " + topic);
}
};
```

And here is my connecting code:

```
protected void connect() throws MqttException {
Log.d(mLogTag, "connect");

MqttConnectOptions connectOptions = new MqttConnectOptions();
connectOptions.setCleanSession(true);
connectOptions.setAutomaticReconnect(false);
connectOptions.setUserName(MQTT_USERNAME);
connectOptions.setPassword(MQTT_PASSWORD.toCharArray());

mClient = new MqttAsyncClient(mBrokerUri.toString(), clientName, new MemoryPersistence());
mClient.setCallback(mCallback);
mClient.connect(connectOptions);

Debug d = ((MqttAsyncClient) mClient).getDebug();
d.dumpClientDebug();
}
```

I do not use the automatic reconnect feature, but would like to handle reconnecting in my own custom code, since I need custom delays.

For testing purposes I do not start MQTT broker yet and try to connect.

I was hoping to detect the initial connection failure in the connectionLost callback method, but it does not get called.

The MqttException is not thrown either.

When I inspect the [paho0.log.0](https://gist.github.com/afarber/e8d165e306ea9ec0d77dfde46447763b) log file I see the failed connection there -

```
FINE 17-03-09 07:55:33.0726 al.TCPNetworkModule start 61 ef978a39c826cd6d4ad22f20d5abe6c236eddb060b5d765a1fe2e1d79837fcc8: Failed to create TCP socket
Throwable occurred: java.net.ConnectException: Connection refused: connect
at java.net.DualStackPlainSocketImpl.waitForConnect(Native Method)
at java.net.DualStackPlainSocketImpl.socketConnect(DualStackPlainSocketImpl.java:85)
at java.net.AbstractPlainSocketImpl.doConnect(AbstractPlainSocketImpl.java:350)
at java.net.AbstractPlainSocketImpl.connectToAddress(AbstractPlainSocketImpl.java:206)
at java.net.AbstractPlainSocketImpl.connect(AbstractPlainSocketImpl.java:188)
at java.net.PlainSocketImpl.connect(PlainSocketImpl.java:172)
at java.net.SocksSocketImpl.connect(SocksSocketImpl.java:392)
at java.net.Socket.connect(Socket.java:589)
at org.eclipse.paho.client.mqttv3.internal.TCPNetworkModule.start(TCPNetworkModule.java:70)
at org.eclipse.paho.client.mqttv3.internal.ClientComms$ConnectBG.run(ClientComms.java:650)
at java.lang.Thread.run(Thread.java:745)
FINE 17-03-09 07:55:33.0727 nternal.ClientComms connectBG:run 61 ef978a39c826cd6d4ad22f20d5abe6c236eddb060b5d765a1fe2e1d79837fcc8: connect failed: unexpected exception
Throwable occurred: Unable to connect to server (32103) - java.net.ConnectException: Connection refused: connect
at org.eclipse.paho.client.mqttv3.internal.TCPNetworkModule.start(TCPNetworkModule.java:79)
at org.eclipse.paho.client.mqttv3.internal.ClientComms$ConnectBG.run(ClientComms.java:650)
at java.lang.Thread.run(Thread.java:745)
Caused by: java.net.ConnectException: Connection refused: connect
at java.net.DualStackPlainSocketImpl.waitForConnect(Native Method)
at java.net.DualStackPlainSocketImpl.socketConnect(DualStackPlainSocketImpl.java:85)
at java.net.AbstractPlainSocketImpl.doConnect(AbstractPlainSocketImpl.java:350)
at java.net.AbstractPlainSocketImpl.connectToAddress(AbstractPlainSocketImpl.java:206)
at java.net.AbstractPlainSocketImpl.connect(AbstractPlainSocketImpl.java:188)
at java.net.PlainSocketImpl.connect(PlainSocketImpl.java:172)
at java.net.SocksSocketImpl.connect(SocksSocketImpl.java:392)
at java.net.Socket.connect(Socket.java:589)
at org.eclipse.paho.client.mqttv3.internal.TCPNetworkModule.start(TCPNetworkModule.java:70)
... 2 more
FINE 17-03-09 07:55:33.0732 nternal.ClientComms shutdownConnection 61 ef978a39c826cd6d4ad22f20d5abe6c236eddb060b5d765a1fe2e1d79837fcc8: state=DISCONNECTING
FINE 17-03-09 07:55:33.0732 ernal.CommsCallback stop 61 ef978a39c826cd6d4ad22f20d5abe6c236eddb060b5d765a1fe2e1d79837fcc8: stopped
FINE 17-03-09 07:55:33.0733 nal.CommsTokenStore quiesce 61 ef978a39c826cd6d4ad22f20d5abe6c236eddb060b5d765a1fe2e1d79837fcc8: resp=Client is currently disconnecting (32102)
```

But how to detect that connection failure in my code? (So that I could initiate the later reconnection).