Java – akka: send back outside the actor system?

I have the following drivers / main classes to encapsulate my akka program:

// Groovy pseudo-code
class FizzBuzz {
    ActorSystem actorSystem

    static void main(String[] args) {
        FizzBuzz d = new FizzBuzz()
        d.run()
    }

    void run() {
        Initialize initCmd = new Initialize()
        MasterActor master = actorSystem.get(...)

        // Tells the entire actor system to initialize itself and start doing stuff.
        // ChickenCluckDetector is an actor managed/supervised by MasterActor.
        master.tell(initCmd,...)
    }

    // Called when a ChickenCluckDetector actor inside the actor system receives
    // a 'Cluck' message.
    void onChickenGoesCluck(Cluck cluck) {
        // Do something
    }
}

The following chickencluckdetector actors:

class ChickenCluckDetector extends UntypedActor {
    @Override
    void onReceive(Object message) {
        if(message instanceof Cluck) {
            Cluck cluck = message as Cluck

            // Now,how to pass the message safely/properly to FizzBuzz#onCluck?
        }
    }
}

So the question at hand is how to safely / correctly pass the cluck message to fizzbuzz#onclick (cluck), which exists outside the actor system? I can provide a fizzbuzz reference about chickencluckdetector, as follows:

class ChickenCluckDetector extends UntypedActor {
    FizzBuzz fizzBuzz

    @Override
    void onReceive(Object message) {
        if(message instanceof Cluck) {
            Cluck cluck = message as Cluck

            fizzBuzz.onCluck(cluck)
        }
    }
}

But I have a feeling that this violates akka's best practice and may lead to various concurrency based problems, especially if there is only one fizzbuzz (with) non actor / driver and 10000 chickncluckdetector actors Ideas?

Solution

Then it's best to create a common parent for all these chickencluckdetectors Then, the parent can safely save a reference to fizzbuzz, receive a cluck from all his children and call the onclick method

One option to get information outside the actor is to ask There is an actor DSL in scala (added for integrity only) But I'm sure you don't need these in your example

public class ChickenCluckMaster extends UntypedActor {

    private FizzBuzz fizzBuzz;

    public ChickenCluckMaster(FizzBuzz fizzBuzz) {
        this.fizzBuzz = fizzBuzz;
    }

    public void onReceive(Object message) throws Exception {
        if (message instanceOf CreateDetector) {
            getContext().actorOf(
                Props.create(ChickenCluckDetector.class,getSelf); // Create child
        } else if (message instanceof Cluck) {
            fizzBuzz.onCluck(cluck);
        } else {
            unhandled(message);
        }
    }

}

public class ChickenCluckDetector extends UntypedActor {

    private ActorRef master;

    public ChickenCluckDetector(ActorRef master) {
        this.master = master;
    }

    public void onReceive(Object message) throws Exception { 
        if (message instanceof Cluck) {
            Cluck cluck = (Cluck) message;
            master.tell(cluck,getSelf);
        } else {
            unhandled(message);
        }
    }

}