Untyped Simple Prime Akka example

UntypedSimplePrime.java

package com.lightbend.akka.sample;

import akka.actor.Props;
import akka.actor.UntypedAbstractActor;

class UntyptedSimplePrime {

    static class IsPrimeActor extends UntypedAbstractActor {

        // Define the messages
        static class IsPrimeRequest {
            long candidate;
            IsPrimeRequest(long candidate){this.candidate = candidate;}
        }

        static class IsPrimeResponse {
            long candidate;
            boolean isPrime;

            IsPrimeResponse(long candidate, boolean isPrime){
                this.candidate = candidate;
                this.isPrime = isPrime;
            }
        }

        IsPrimeResponse onPrimeRequest(IsPrimeRequest m) {
            return new IsPrimeResponse(m.candidate, isPrime(m.candidate));
        }

        @Override
        public void onReceive(Object message) throws Throwable {
            IsPrimeResponse reply = onPrimeRequest(IsPrimeRequest.class.cast(message));
            getSender().tell(reply, getSelf());
        }

        private boolean isPrime(long n) {
            if (n <= 3) {
                return n > 1;
            } else if (n % 2 == 0 || n % 3 == 0) {
                return false;
            } else {
                for (int i = 5; i * i <= n; i += 6) {
                    if (n % i == 0 || n % (i + 2) == 0) {
                        return false;
                    }
                }
                return true;
            }
        }

        public static Props props() {
            return Props.create(IsPrimeActor.class);
        }
    }
}

UntypedSimplePrimeTest.java

package com.lightbend.akka.sample;

import akka.actor.ActorRef;
import akka.actor.ActorSystem;
import akka.testkit.javadsl.TestKit;
import org.junit.AfterClass;
import org.junit.BeforeClass;
import org.junit.Test;

import static org.junit.Assert.assertEquals;

public class UntyptedSimplePrimeTest {
  static ActorSystem system;

  @BeforeClass
  public static void setup() {
    system = ActorSystem.create();
  }

  @AfterClass
  public static void teardown() {
    TestKit.shutdownActorSystem(system);
    system = null;
  }

  @Test
  public void testReplyWithSmallCandidates() {
    TestKit probe = new TestKit(system);
    ActorRef primeActor = system.actorOf(UntyptedSimplePrime.IsPrimeActor.props());

    primeActor.tell(new UntyptedSimplePrime.IsPrimeActor.IsPrimeRequest(42L), probe.getRef());

    UntyptedSimplePrime.IsPrimeActor.IsPrimeResponse response = probe.expectMsgClass(UntyptedSimplePrime.IsPrimeActor.IsPrimeResponse.class);

    assertEquals(42L, response.candidate);
    assertEquals(false, response.isPrime);
  }

  @Test
  public void testReplyWithMultipleCandidates() {
    TestKit probe = new TestKit(system);
    ActorRef primeActor = system.actorOf(UntyptedSimplePrime.IsPrimeActor.props());

    for (long i = 0; i < 10000; i++) {
      primeActor.tell(new UntyptedSimplePrime.IsPrimeActor.IsPrimeRequest(i), probe.getRef());

      UntyptedSimplePrime.IsPrimeActor.IsPrimeResponse response = probe.expectMsgClass(UntyptedSimplePrime.IsPrimeActor.IsPrimeResponse.class);

      assertEquals(i, response.candidate);
    }
  }

}