Akka(Java)教程中不推荐使用"UntypedActor"的解决方案

Question

原始代码

Akka教程包含以下代码:http://doc.akka.io/docs/akka/2.0.2/intro/getting-started-first-java.html

public void calculate (final int nrOfWorkers, final int nrOfElements, final int nrOfMessages){
    ActorSystem system = ActorSystem.create("PiSystem");
    final ActorRef listener = system.actorOf(Props.create(Listener.class), "listener");
    ActorRef master = system.actorOf(new Props(new UntypedActorFactory() {
            public UntypedActor create() {
                return new Master(nrOfWorkers, nrOfMessages, nrOfElements, listener);
            }
    }), "master");
    master.tell(new Calculate(), ActorRef.noSender());
}

其中,UntypedActorFactory已弃用.

我的Mod

所以我试着用Props.create这样的

ActorRef master = system.actorOf( Props.create(
            new Creator<Master>(){
                public Master create(){
                    return new Master(nrOfWorkers, nrOfMessages, nrOfElements, listener);
            }
    }), "master");

并且有例外说

不能使用非静态本地Creator来创建actor; 使它静态或顶级

所以我开始写一个静态类,它需要传递参数.

static class LocalCreator implements Creator<Master>{
    public Master create(){
        return new Master(nrOfWorkers, nrOfMessages, nrOfElements, listener);
    }
}

题

如何create()优雅地将参数nrOfWorkers等传递给函数？

Answer 1

如果您阅读了Akka文档(Java风格),它列出了两种构造具有构造函数参数的actor的方法.第一个是这样的(使用您的示例类):

ActorSystem system = ActorSystem.create("PiSystem");
final ActorRef listener = system.actorOf(Props.create(Listener.class), "listener");
ActorRef master = system.actorOf(Props.create(Master.class, nrOfWorkers, nrOfMessages, nrOfElements, listener), "master");
master.tell(new Calculate(), ActorRef.noSender());

或者如果你不想走那条路,你可以这样使用Creator:

public class MasterCreator implements Creator<Master>{
  private int nrOfWorkers, nrOfMessages, nrOfElements;
  private ActorRef listener;
  public MasterCreator(int nrOfWorkers, int nrOfMessages, int nrOfElements, ActorRef listener){
    this.listener = listener;
    this.nrOfElements = nrOfElements;
    this.nrOfMessages = nrOfMessages;
    this.nrOfWorkers = nrOfWorkers;
  }

  public Master create(){
    return new Master(nrOfWorkers, nrOfMessages, nrOfElements, listener);
  }
}

然后像这样使用它:

  ActorSystem system = ActorSystem.create("PiSystem");
  final ActorRef listener = system.actorOf(Props.create(Listener.class), "listener");
  ActorRef master = system.actorOf(Props.create(new MasterCreator(nrOfWorkers, nrOfMessages, nrOfElements, listener)), "master");
  master.tell(new Calculate(), ActorRef.noSender());