Akka/Scala example source code file (MyUnboundedMailbox.scala)

This example Akka source code file (MyUnboundedMailbox.scala) is included in my "Source Code Warehouse" project. The intent of this project is to help you more easily find Akka and Scala source code examples by using tags.

All credit for the original source code belongs to akka.io; I'm just trying to make examples easier to find. (For my Scala work, see my Scala examples and tutorials.)

Akka tags/keywords

actor, actorref, akka, dispatch, envelope, int, mailboxtype, messagequeue, mymessagequeue, myunboundedmailbox, myunboundedmessagequeuesemantics, option, unit

The MyUnboundedMailbox.scala Akka example source code

/**
 * Copyright (C) 2009-2014 Typesafe Inc. <http://www.typesafe.com>
 */

package docs.dispatcher

//#mailbox-implementation-example
import akka.actor.ActorRef
import akka.actor.ActorSystem
import akka.dispatch.Envelope
import akka.dispatch.MailboxType
import akka.dispatch.MessageQueue
import akka.dispatch.ProducesMessageQueue
import com.typesafe.config.Config
import java.util.concurrent.ConcurrentLinkedQueue
import scala.Option

// Marker trait used for mailbox requirements mapping
trait MyUnboundedMessageQueueSemantics

object MyUnboundedMailbox {
  // This is the MessageQueue implementation
  class MyMessageQueue extends MessageQueue
    with MyUnboundedMessageQueueSemantics {

    private final val queue = new ConcurrentLinkedQueue[Envelope]()

    // these should be implemented; queue used as example
    def enqueue(receiver: ActorRef, handle: Envelope): Unit =
      queue.offer(handle)
    def dequeue(): Envelope = queue.poll()
    def numberOfMessages: Int = queue.size
    def hasMessages: Boolean = !queue.isEmpty
    def cleanUp(owner: ActorRef, deadLetters: MessageQueue) {
      while (hasMessages) {
        deadLetters.enqueue(owner, dequeue())
      }
    }
  }
}

// This is the Mailbox implementation
class MyUnboundedMailbox extends MailboxType
  with ProducesMessageQueue[MyUnboundedMailbox.MyMessageQueue] {

  import MyUnboundedMailbox._

  // This constructor signature must exist, it will be called by Akka
  def this(settings: ActorSystem.Settings, config: Config) = {
    // put your initialization code here
    this()
  }

  // The create method is called to create the MessageQueue
  final override def create(owner: Option[ActorRef],
                            system: Option[ActorSystem]): MessageQueue =
    new MyMessageQueue()
}
//#mailbox-implementation-example