public abstract class AbstractEventMessage<T>
 implements EventMessage
                    

Simple message container to ease use with com.google.common.eventbus.EventBus.

Google Guava's event bus library dispatches events based on function parametrization. Given a class with a com.google.common.eventbus.Subscribe annotation:

public class Foo {
    @Subscribe
    void doSomethingWith(Bar payload) {
        // ...
    }
}

If an instance of Foo is registered for an event bus and post with a Bar instance is invoked, Guava knows which function to call by looking at the parameters of all Subsribe-annotated functions.

The abstract event message helps in strong-typing EventBus-accepted functions and encapsulates a default payload that is requestable by using the getPayload method.