Not able to receive ACLMessage in android via JADE

Question

I'm currently using Topic based communication using JADE. I'm able to register a JADE agent using jade.core.messaging.TopicManagementFEService thereby connecting to the main-container in the same platform.

The details are below:

1. Main-Container: a simple LAMP/WAMP Server that hosts the Main-Container.
2. Client: An Android Emulator(testing purpose) to connect to the main-container.

Currently,

1. Server starts the main-container
2. Android emulator connects to the Main-container successfully (Agent created along with Topic Mgmt Service enabled)
3. Server is sending messages based on a specific topic.

But my Android Client is not able to receive this message although the topic registered is the same on both ends!

You can see the code below:

Server Side:

TopicManagementHelper topicHelper = (TopicManagementHelper) getHelper(TopicManagementHelper.SERVICE_NAME);
final AID sensorTopic = topicHelper.createTopic("JADE");
topicHelper.register(sensorTopic);

addBehaviour(new TickerBehaviour(this, TIMER_VALUE_IN_MILLISECONDS) {

private static final long serialVersionUID = -2567778187494378326L;

    public void onTick() {

        ACLMessage msg = new ACLMessage(ACLMessage.INFORM);
        msg.addReceiver(eventTopic);
        msg.setContent(eventValue);
        myAgent.send(msg);
    }
});

Android Side:

// Registering on Android Side as well
TopicManagementHelper topicHelper = (TopicManagementHelper) getHelper(TopicManagementHelper.SERVICE_NAME);
topic = topicHelper.createTopic("JADE"); // See, same topic!
topicHelper.register(topic);

behaviour = new myBehaviour(this, TIMER_VALUE_IN_MILLISECONDS, topic);
addBehaviour(behaviour);

private class myBehaviour extends TickerBehaviour {

 private static final long serialVersionUID = 4782913834042415090L;
 AID topic;
 Agent agent;
 MessageTemplate tpl;

   public myBehaviour(Agent a, long period, AID topic) {
    super(a, period);

    this.agent = a;
    this.topic = topic;
   }

   public void onTick() {
    tpl = MessageTemplate.MatchTopic(topic);
    ACLMessage msg = receive(tpl);
    if (msg != null) {
       logger.log(Level.INFO, "Agent "+ agent.getLocalName() + 
                           ": Message about topic "+ topic.getLocalName() +" received. \n" +
                                    "Content is " + msg.getContent());
       data = msg.getContent();

    } else {
       logger.log(Level.INFO, "In here..."); // Always executes only this code!
       block();
    }
  }
}

Where am I going wrong here? It always executes the else part in the Android side which is obvious to say that message received is NULL!

Answer 1

Never mind. The logic was wrong. The Android-Agent was not identifying itself to the Central-Agent.

I set the Ontology so that the Central Agent is able to identify such message and sends the message accordingly. Now, it is receiving messages!

Self-help works sometimes! ;-)

Answer 2

Receiving topic messages doesn't work correctly with Android up to version 4.3.0 in JADE. Android can send out topic messages but can't receive them. I found this out through my own issues. I've posted more info about it in my own question on stack overflow.

Take a look. JADE Leap Android App unable to receive topic messages