Scala example source code file (ReactorCanReply.scala)

This example Scala source code file (ReactorCanReply.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, any, any, canreply, future, future, outputchannel, outputchannel, reactchannel, reactorcanreply, replyreactor, some, unit

The Scala ReactorCanReply.scala source code

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


package scala.actors

/**
 * Provides message send operations that
 * may result in a response from the receiver.
 *
 * @author Philipp Haller
 */
private[actors] trait ReactorCanReply extends CanReply[Any, Any] {
  _: ReplyReactor =>
  
  type Future[+P] = scala.actors.Future[P]

  def !?(msg: Any): Any =
    (this !! msg)()

  def !?(msec: Long, msg: Any): Option[Any] = {
    val myself = Actor.rawSelf(this.scheduler)
    val res = new scala.concurrent.SyncVar[Any]
    val out = new OutputChannel[Any] {
      def !(msg: Any) =
        res set msg
      def send(msg: Any, replyTo: OutputChannel[Any]) =
        res set msg
      def forward(msg: Any) =
        res set msg
      def receiver =
        myself.asInstanceOf[Actor]
    }
    this.send(msg, out)
    res.get(msec)
  }

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

  def !![A](msg: Any, handler: PartialFunction[Any, A]): Future[A] = {
    val myself = Actor.rawSelf(this.scheduler)
    val ftch = new ReactChannel[A](myself)
    val res = new scala.concurrent.SyncVar[A]

    val out = new OutputChannel[Any] {
      def !(msg: Any) = {
        val msg1 = handler(msg)
        ftch ! msg1
        res set msg1
      }
      def send(msg: Any, replyTo: OutputChannel[Any]) = {
        val msg1 = handler(msg)
        ftch.send(msg1, replyTo)
        res set msg1
      }
      def forward(msg: Any) = {
        val msg1 = handler(msg)
        ftch forward msg1
        res set msg1
      }
      def receiver =
        myself.asInstanceOf[Actor]
    }

    this.send(msg, out)

    new Future[A] {
      def apply() = {
        if (!isSet)
          fvalue = Some(res.get)
        
        fvalueTyped
      }
      def respond(k: A => Unit): Unit =
        if (isSet) k(fvalueTyped)
        else inputChannel.react {
          case any => fvalue = Some(any); k(fvalueTyped)
        }
      def isSet =
        !fvalue.isEmpty
      def inputChannel = ftch
    }
  }
}