Scala：如何扩展Akka演员？

我写了一个阿克卡基地的演员，可以处理一些常见的信息。我希望通过扩展基本角色（而不是通过基本角色的组合），在子角色中重用这个基本行为

我在前面的问题中看到了几种方法。它们都是有效的，但也可以改进：

及

为了使实现更简洁，我正在尝试实现以下目标：

• 定义子参与者时，我尝试只扩展基本参与者（而不是同时扩展

  actor

  和

  sub-actor

  ）。但是，我无法强制编译器执行此操作
• 我还尝试不重命名

  receive

  partial函数，因为这是一种约定

以下是我的实现示例：

//This is the base-actor that implements the common behavior

trait BetterActor extends Actor {

  abstract override def receive = {
    super.receive orElse { case _ => println("Missing pattern!") }
  }
}

//This is the actor that implements the additional behavior.
//I actually wanted to extend BetterActor. It was not possible.

class MyActor extends Actor {

  def receive = {
    case i: Int =>
      println(s"Yay!!! Got $i")
  }
}

//1.

val myBetterActor = system.actorOf(Props(new MyActor with BetterActor), "myBetterActor")

//2.

class MyBetterActor extends MyActor with BetterActor
val myBetterActor = system.actorOf(Props[MyBetterActor], "myBetterActor")

myBetterActor ! 2
myBetterActor ! "a"

这里有两种可选方法，我可以创建子参与者的实例，它结合了常见行为和其他行为：

//This is the base-actor that implements the common behavior

trait BetterActor extends Actor {

  abstract override def receive = {
    super.receive orElse { case _ => println("Missing pattern!") }
  }
}

//This is the actor that implements the additional behavior.
//I actually wanted to extend BetterActor. It was not possible.

class MyActor extends Actor {

  def receive = {
    case i: Int =>
      println(s"Yay!!! Got $i")
  }
}

//1.

val myBetterActor = system.actorOf(Props(new MyActor with BetterActor), "myBetterActor")

//2.

class MyBetterActor extends MyActor with BetterActor
val myBetterActor = system.actorOf(Props[MyBetterActor], "myBetterActor")

myBetterActor ! 2
myBetterActor ! "a"

最后，我可以通过以下方式调用子参与者：

//This is the base-actor that implements the common behavior

trait BetterActor extends Actor {

  abstract override def receive = {
    super.receive orElse { case _ => println("Missing pattern!") }
  }
}

//This is the actor that implements the additional behavior.
//I actually wanted to extend BetterActor. It was not possible.

class MyActor extends Actor {

  def receive = {
    case i: Int =>
      println(s"Yay!!! Got $i")
  }
}

//1.

val myBetterActor = system.actorOf(Props(new MyActor with BetterActor), "myBetterActor")

//2.

class MyBetterActor extends MyActor with BetterActor
val myBetterActor = system.actorOf(Props[MyBetterActor], "myBetterActor")

myBetterActor ! 2
myBetterActor ! "a"

我的实现存在问题：

//This is the base-actor that implements the common behavior

trait BetterActor extends Actor {

  abstract override def receive = {
    super.receive orElse { case _ => println("Missing pattern!") }
  }
}

//This is the actor that implements the additional behavior.
//I actually wanted to extend BetterActor. It was not possible.

class MyActor extends Actor {

  def receive = {
    case i: Int =>
      println(s"Yay!!! Got $i")
  }
}

//1.

val myBetterActor = system.actorOf(Props(new MyActor with BetterActor), "myBetterActor")

//2.

class MyBetterActor extends MyActor with BetterActor
val myBetterActor = system.actorOf(Props[MyBetterActor], "myBetterActor")

myBetterActor ! 2
myBetterActor ! "a"

当我创建子actor的实例时，只有这样，我才能直接（1）或通过定义一个新类来混合基本actor

正如我之前所说的，当我定义子角色时，我更喜欢混合基本角色。当我尝试创建子参与者的实例时，情况就不是这样了

---

p.S.令人着迷的是，这个框架的设计者并不认为有必要使这个通用需求易于实现。

我想只要你不想用BetterActor覆盖行为，你就可以尝试这样的方法：

trait BetterActor extends Actor {
  override def unhandled(message: Any): Unit = message match {
    case e: CommonMessage => println("COMMON!")
    case e => super.unhandled(e)
  }
}

class MyActor extends BetterActor {
  override def receive = {
    case i: Int => println(s"Yay!!! Got $i")
  }
}

---

此框架的设计者已经在

Actor

中创建了

未处理的
方法-您只需重写它就足够了it@ghik我不明白你的一行程序。它能编译吗？我想你的意思是
未处理（message:Any）：Unit={message match{…}
也不需要
覆盖
def receive
。另外，正如您所说，
receive
将覆盖基本actor中未处理的
。这样做是有道理的。这是一个很好的解决办法。谢谢你。@rapt-oops，我太笨了。是的，关于那场比赛你是对的。我将编辑答案以反映这一点。