AgE 2.6 : Messages

Messages Structure

Messages in AgE are similar to JMS and other messaging systems. They consist in a header and a payload.

Creating Messages

You can easily create messages using utility functions from the org.jage.communication.message.Messages class:

UnicastSelector<IAddress> selector = Selectors.unicastFor(targetAddress);
Message<IAddress, String> message = Messages.newUnicastMessage(myAddress, selector, "Hello world!");

Sending Messages

To send a message between agents, use methods available in the environment:

doAction(AgentActions.sendMessage(message));

As you can see, message delivery is considered as an action. It means that its execution will be deferred until the end of the current step. The intended consequence is that messages sent in one step will be only made available to their receivers in the next step.

In turn, to send messages between components in different nodes, use the communication service:

@Inject
private CommunicationService communicationService;
...
communicationService.send(message);

Receiving Messages

Every agent is provided with a message queue. Agent receive messages actively by querying their message queue:

import static com.google.common.collect.Iterables.consumingIterable;
...
for (IMessage<AgentAddress, ?> message : consumingIterable(getMessages())) {
  read(message);
}