În imposibilitatea de a trimite un mesaj la un akka de la distanță actor

Sunt nou la akka remoting și încerc să pur și simplu trimite un mesaj de la un actor de la distanță și de a obține un răspuns în schimb. Am 2 actor sisteme de pe localhost - porturi diferite: MasterSystem și WorkerSystem. Am creat un actor în WorkerSystem și a încercat să trimită un mesaj la adresa. Dar I a păstra pe obtinerea unui mort litere întâlnit' mesaj! Ar aprecia orice ajutor. Multumesc!!!

MainMaster.java

package pi_swarm_approx;

import akka.actor.ActorRef;
import akka.actor.ActorSelection;
import akka.actor.ActorSystem;
import akka.actor.UntypedActor;
import com.typesafe.config.ConfigFactory;

public class MainMaster extends UntypedActor{
    ActorSystem system;
    ActorRef actor;
    ActorSelection remoteActor;
    
    public MainMaster() {
        system = ActorSystem.create("MasterSystem", ConfigFactory.load("master"));
        System.out.println("MasterSystem created");
        MainWorker mw = new MainWorker();
        System.out.println("MainWorker obj created");
        remoteActor = mw.system.actorSelection("akka://WorkerSystem@localhost:2552/user/workerActor");
        
        System.out.println("Remote actor created");    
        remoteActor.tell("hello", getSelf());
        System.out.println("Message sent to remote actor");
    }
    
    public void onReceive(Object msg) {
        if (msg != null) {
            System.out.println("Got it back");
        }
         else {
            unhandled(msg);
            getContext().stop(getSelf());
         }
    }
}

MainWorker.java

package pi_swarm_approx;

import akka.actor.ActorSystem;
import akka.actor.ActorRef;
import com.typesafe.config.ConfigFactory;
import akka.actor.Props;

public class MainWorker {
    ActorSystem system;
    ActorRef actor;
    public MainWorker() {
        this.system = ActorSystem.create("WorkerSystem", ConfigFactory.load("worker"));
        actor = system.actorOf(Props.create(Worker.class), "workerActor");
    }
}

Worker.java

package pi_swarm_approx;

import akka.actor.UntypedActor;

public class Worker extends UntypedActor {  
    public void onReceive(Object msg) {
        System.out.println("Worker actor got message");
        if (msg != null) {
            getSender().tell("Request processed", getSelf());
        }
         else {
            unhandled(msg);
         }
        getContext().stop(getSelf());
    }
}

master.conf

akka {
  actor {
    provider = "cluster"
  }
  remote {
  transport = ["akka.remote.netty.tcp"]
    netty.tcp {
      hostname = "localhost"
      port = 2551
    }
  }
  
  clustering {
    cluster.name = "MasterSystem"
    role = "master"
  }
 }

lucrător.conf

akka {
  actor {
    provider = "cluster"
    deployment {
        /workerActor {
          remote = "akka.tcp://WorkerSystem@localhost:2552"
        }
  }
}

Ieșire

In main
MasterSystem created
MainWorker obj created
Remote actor created
Message sent to remote actor
[INFO] [11/22/2021 16:01:34.531] [WorkerSystem-akka.actor.default-dispatcher-5] [akka://WorkerSystem/deadLetters] Message [java.lang.String] from Actor[akka://Main/user/app#402333018] to Actor[akka://WorkerSystem/deadLetters] was not delivered. [1] dead letters encountered. If this is not an expected behavior, then [Actor[akka://WorkerSystem/deadLetters]] may have terminated unexpectedly, This logging can be turned off or adjusted with configuration settings 'akka.log-dead-letters' and 'akka.log-dead-letters-during-shutdown'.
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