Scala example source code file (ActorCanReply.scala)

This example Scala source code file (ActorCanReply.scala) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Java - Scala tags/keywords

a, a, actorcanreply, any, any, future, future, none, outputchannel, partialfunction, partialfunction, reactorcanreply, some, timeout

The Scala ActorCanReply.scala source code

/*                     __                                               *\
**     ________ ___   / /  ___     Scala API                            **
**    / __/ __// _ | / /  / _ |    (c) 2005-2011, LAMP/EPFL             **
**  __\ \/ /__/ __ |/ /__/ __ |    http://scala-lang.org/               **
** /____/\___/_/ |_/____/_/ | |                                         **
**                          |/                                          **
\*                                                                      */


package scala.actors

import scala.concurrent.SyncVar

/**
 * Provides message send operations that
 * may result in a response from the receiver.
 *
 * @author Philipp Haller
 */
private[actors] trait ActorCanReply extends ReactorCanReply {
  this: AbstractActor with ReplyReactor =>

  override def !?(msg: Any): Any = {
    val replyCh = new Channel[Any](Actor.self(scheduler))
    send(msg, replyCh)
    replyCh.?
  }

  override def !?(msec: Long, msg: Any): Option[Any] = {
    val replyCh = new Channel[Any](Actor.self(scheduler))
    send(msg, replyCh)
    replyCh.receiveWithin(msec) {
      case TIMEOUT => None
      case x => Some(x)
    }
  }

  override def !![A](msg: Any, handler: PartialFunction[Any, A]): Future[A] = {
    val c = new Channel[A](Actor.self(scheduler))
    val fun = (res: SyncVar[A]) => {
      val ftch = new Channel[A](Actor.self(scheduler))
      send(msg, new OutputChannel[Any] {
        def !(msg: Any) =
          ftch ! handler(msg)
        def send(msg: Any, replyTo: OutputChannel[Any]) =
          ftch.send(handler(msg), replyTo)
        def forward(msg: Any) =
          ftch.forward(handler(msg))
        def receiver =
          ftch.receiver
      })
      ftch.react {
        case any => res.set(any)
      }
    }
    val a = new FutureActor[A](fun, c)
    a.start()
    a
  }

  override def !!(msg: Any): Future[Any] = {
    val noTransform: PartialFunction[Any, Any] = { case x => x }
    this !! (msg, noTransform)
  }

}