Example for A java actor library https://github.com/edescourtis/actor

ActorExample.java

package com.test.actor;
 
import com.benbria.actor.Actor;
import com.benbria.actor.Behaviour;
import com.benbria.actor.ThreadActor;
 
public class ActorExample {
  public static void main(String[] args) throws InterruptedException {
    Actor<String> actor = ThreadActor.spawn(new Behaviour<String>() {
      @Override
      public boolean receive(Actor<String> self, String msg) {
        System.out.println("Got: " + msg);
        return !msg.equals("stop");
      }
 
      @Override
      public void exception(Actor<String> self, Exception e) {
      }
    });
 
    actor.send("hello");
    actor.send("world");
    Thread.sleep(1000);
    actor.send("stop");
    
    // as soon as stop message sent to actor, it will stop
    // and following lines will not printed.
    actor.send("hello");
    actor.send("world");
  }
}

*Output:-*
  Got: hello
  Got: world
  Got: stop