move deadLetterMailbox into Mailboxes and fix review comments, see #3342

akka-actor/src/main/resources/reference.conf

@@ -293,7 +293,8 @@ akka {
     }
     
     default-mailbox {
-      # FQCN of the MailboxType. The Class of the FQCN must have a public constructor with
+      # FQCN of the MailboxType. The Class of the FQCN must have a public 
+      # constructor with 
       # (akka.actor.ActorSystem.Settings, com.typesafe.config.Config) parameters.
       mailbox-type = "akka.dispatch.UnboundedMailbox"
 
@@ -301,7 +302,7 @@ akka {
       # capacity. The provided value must be positive.
       # NOTICE:
       # Up to version 2.1 the mailbox type was determined based on this setting;
-      # this is no longer the case, the type must explicitly name a bounded mailbox.
+      # this is no longer the case, the type must explicitly be a bounded mailbox.
       mailbox-capacity = 1000
 
       # If the mailbox is bounded then this is the timeout for enqueueing 

akka-actor/src/main/scala/akka/actor/ActorSystem.scala

@@ -544,25 +544,10 @@ private[akka] class ActorSystemImpl(val name: String, applicationConfig: Config,
 
   def deadLetters: ActorRef = provider.deadLetters
 
-  val deadLetterMailbox: Mailbox = new Mailbox(new MessageQueue {
-    def enqueue(receiver: ActorRef, envelope: Envelope): Unit =
-      deadLetters.tell(DeadLetter(envelope.message, envelope.sender, receiver), envelope.sender)
-    def dequeue() = null
-    def hasMessages = false
-    def numberOfMessages = 0
-    def cleanUp(owner: ActorRef, deadLetters: MessageQueue): Unit = ()
-  }) {
-    becomeClosed()
-    def systemEnqueue(receiver: ActorRef, handle: SystemMessage): Unit =
-      deadLetters ! DeadLetter(handle, receiver, receiver)
-    def systemDrain(newContents: LatestFirstSystemMessageList): EarliestFirstSystemMessageList = SystemMessageList.ENil
-    def hasSystemMessages = false
-  }
-
-  val mailboxes: Mailboxes = new Mailboxes(settings, eventStream, dynamicAccess)
+  val mailboxes: Mailboxes = new Mailboxes(settings, eventStream, dynamicAccess, deadLetters)
 
   val dispatchers: Dispatchers = new Dispatchers(settings, DefaultDispatcherPrerequisites(
-    threadFactory, eventStream, deadLetterMailbox, scheduler, dynamicAccess, settings, mailboxes))
+    threadFactory, eventStream, scheduler, dynamicAccess, settings, mailboxes))
 
   val dispatcher: ExecutionContext = dispatchers.defaultGlobalDispatcher
 

akka-actor/src/main/scala/akka/actor/dungeon/Dispatch.scala

@@ -59,7 +59,7 @@ private[akka] trait Dispatch { this: ActorCell ⇒
         val req = system.mailboxes.getRequiredType(actorClass)
         if (req isInstance mbox.messageQueue) Create(None)
         else Create(Some(ActorInitializationException(self,
-          s"Actor [$self] requires mailbox type [$req] got [${mbox.messageQueue.getClass}]")))
+          s"Actor [$self] requires mailbox type [$req] got [${mbox.messageQueue.getClass.getName}]")))
       case _ ⇒ Create(None)
     }
 

akka-actor/src/main/scala/akka/dispatch/AbstractDispatcher.scala

@@ -87,7 +87,10 @@ abstract class MessageDispatcher(val configurator: MessageDispatcherConfigurator
 
   import MessageDispatcher._
   import AbstractMessageDispatcher.{ inhabitantsOffset, shutdownScheduleOffset }
-  import configurator.prerequisites._
+  import configurator.prerequisites
+
+  val mailboxes = prerequisites.mailboxes
+  val eventStream = prerequisites.eventStream
 
   @volatile private[this] var _inhabitantsDoNotCallMeDirectly: Long = _ // DO NOT TOUCH!
   @volatile private[this] var _shutdownScheduleDoNotCallMeDirectly: Int = _ // DO NOT TOUCH!
@@ -168,7 +171,7 @@ abstract class MessageDispatcher(val configurator: MessageDispatcherConfigurator
 
   private def scheduleShutdownAction(): Unit = {
     // IllegalStateException is thrown if scheduler has been shutdown
-    try scheduler.scheduleOnce(shutdownTimeout, shutdownAction)(new ExecutionContext {
+    try prerequisites.scheduler.scheduleOnce(shutdownTimeout, shutdownAction)(new ExecutionContext {
       override def execute(runnable: Runnable): Unit = runnable.run()
       override def reportFailure(t: Throwable): Unit = MessageDispatcher.this.reportFailure(t)
     }) catch {
@@ -196,7 +199,7 @@ abstract class MessageDispatcher(val configurator: MessageDispatcherConfigurator
   protected[akka] def unregister(actor: ActorCell) {
     if (debug) actors.remove(this, actor.self)
     addInhabitants(-1)
-    val mailBox = actor.swapMailbox(deadLetterMailbox)
+    val mailBox = actor.swapMailbox(mailboxes.deadLetterMailbox)
     mailBox.becomeClosed()
     mailBox.cleanUp()
   }

akka-actor/src/main/scala/akka/dispatch/BalancingDispatcher.scala

@@ -55,7 +55,7 @@ class BalancingDispatcher(
   private class SharingMailbox(val system: ActorSystemImpl, _messageQueue: MessageQueue)
     extends Mailbox(_messageQueue) with DefaultSystemMessageQueue {
     override def cleanUp(): Unit = {
-      val dlq = system.deadLetterMailbox
+      val dlq = mailboxes.deadLetterMailbox
       //Don't call the original implementation of this since it scraps all messages, and we don't want to do that
       var messages = systemDrain(new LatestFirstSystemMessageList(NoMessage))
       while (messages.nonEmpty) {

akka-actor/src/main/scala/akka/dispatch/Dispatchers.scala

@@ -19,7 +19,6 @@ import akka.actor.Deploy
 trait DispatcherPrerequisites {
   def threadFactory: ThreadFactory
   def eventStream: EventStream
-  def deadLetterMailbox: Mailbox
   def scheduler: Scheduler
   def dynamicAccess: DynamicAccess
   def settings: ActorSystem.Settings
@@ -32,7 +31,6 @@ trait DispatcherPrerequisites {
 private[akka] case class DefaultDispatcherPrerequisites(
   val threadFactory: ThreadFactory,
   val eventStream: EventStream,
-  val deadLetterMailbox: Mailbox,
   val scheduler: Scheduler,
   val dynamicAccess: DynamicAccess,
   val settings: ActorSystem.Settings,
@@ -188,11 +186,14 @@ class DispatcherConfigurator(config: Config, prerequisites: DispatcherPrerequisi
   override def dispatcher(): MessageDispatcher = instance
 }
 
-object BalancingDispatcherConfigurator {
+/**
+ * INTERNAL API
+ */
+private[akka] object BalancingDispatcherConfigurator {
   private val defaultRequirement =
     ConfigFactory.parseString("mailbox-requirement = akka.dispatch.MultipleConsumerSemantics")
   def amendConfig(config: Config): Config =
-    if (config.getString("mailbox-requirement") != "") config
+    if (config.getString("mailbox-requirement") != Mailboxes.NoMailboxRequirement) config
     else defaultRequirement.withFallback(config)
 }
 

akka-actor/src/main/scala/akka/dispatch/Mailbox.scala

@@ -269,7 +269,7 @@ private[akka] abstract class Mailbox(val messageQueue: MessageQueue)
      * if we closed the mailbox, we must dump the remaining system messages
      * to deadLetters (this is essential for DeathWatch)
      */
-    val dlm = actor.systemImpl.deadLetterMailbox
+    val dlm = actor.dispatcher.mailboxes.deadLetterMailbox
     while (messageList.nonEmpty) {
       val msg = messageList.head
       messageList = messageList.tail
@@ -295,7 +295,7 @@ private[akka] abstract class Mailbox(val messageQueue: MessageQueue)
    */
   protected[dispatch] def cleanUp(): Unit =
     if (actor ne null) { // actor is null for the deadLetterMailbox
-      val dlm = actor.systemImpl.deadLetterMailbox
+      val dlm = actor.dispatcher.mailboxes.deadLetterMailbox
       var messageList = systemDrain(new LatestFirstSystemMessageList(NoMessage))
       while (messageList.nonEmpty) {
         // message must be “virgin” before being able to systemEnqueue again
@@ -306,7 +306,7 @@ private[akka] abstract class Mailbox(val messageQueue: MessageQueue)
       }
 
       if (messageQueue ne null) // needed for CallingThreadDispatcher, which never calls Mailbox.run()
-        messageQueue.cleanUp(actor.self, actor.systemImpl.deadLetterMailbox.messageQueue)
+        messageQueue.cleanUp(actor.self, actor.dispatcher.mailboxes.deadLetterMailbox.messageQueue)
     }
 }
 
@@ -394,7 +394,7 @@ private[akka] trait DefaultSystemMessageQueue { self: Mailbox ⇒
     if (Mailbox.debug) println(receiver + " having enqueued " + message)
     val currentList = systemQueueGet
     if (currentList.head == NoMessage) {
-      if (actor ne null) actor.systemImpl.deadLetterMailbox.systemEnqueue(receiver, message)
+      if (actor ne null) actor.dispatcher.mailboxes.deadLetterMailbox.systemEnqueue(receiver, message)
     } else {
       if (!systemQueuePut(currentList, message :: currentList)) {
         message.unlink()

akka-actor/src/main/scala/akka/dispatch/Mailboxes.scala

@@ -18,16 +18,40 @@ import akka.actor.Deploy
 import scala.util.Try
 import scala.util.Failure
 import scala.util.control.NonFatal
-import akka.dispatch.DispatcherPrerequisites
+import akka.actor.ActorRef
+import akka.actor.DeadLetter
+import akka.dispatch.sysmsg.SystemMessage
+import akka.dispatch.sysmsg.LatestFirstSystemMessageList
+import akka.dispatch.sysmsg.EarliestFirstSystemMessageList
+import akka.dispatch.sysmsg.SystemMessageList
 
 object Mailboxes {
   final val DefaultMailboxId = "akka.actor.default-mailbox"
+  final val NoMailboxRequirement = ""
 }
 
 private[akka] class Mailboxes(
   val settings: ActorSystem.Settings,
   val eventStream: EventStream,
-  dynamicAccess: DynamicAccess) {
+  dynamicAccess: DynamicAccess,
+  deadLetters: ActorRef) {
+
+  import Mailboxes._
+
+  val deadLetterMailbox: Mailbox = new Mailbox(new MessageQueue {
+    def enqueue(receiver: ActorRef, envelope: Envelope): Unit =
+      deadLetters.tell(DeadLetter(envelope.message, envelope.sender, receiver), envelope.sender)
+    def dequeue() = null
+    def hasMessages = false
+    def numberOfMessages = 0
+    def cleanUp(owner: ActorRef, deadLetters: MessageQueue): Unit = ()
+  }) {
+    becomeClosed()
+    def systemEnqueue(receiver: ActorRef, handle: SystemMessage): Unit =
+      deadLetters ! DeadLetter(handle, receiver, receiver)
+    def systemDrain(newContents: LatestFirstSystemMessageList): EarliestFirstSystemMessageList = SystemMessageList.ENil
+    def hasSystemMessages = false
+  }
 
   private val mailboxTypeConfigurators = new ConcurrentHashMap[String, MailboxType]
 
@@ -72,7 +96,7 @@ private[akka] class Mailboxes(
   private var mailboxSizeWarningIssued = false
 
   def getMailboxRequirement(config: Config) = config.getString("mailbox-requirement") match {
-    case "" ⇒ classOf[MessageQueue]
+    case NoMailboxRequirement ⇒ classOf[MessageQueue]
     case x                    ⇒ dynamicAccess.getClassFor[AnyRef](x).get
   }
 
@@ -136,7 +160,7 @@ private[akka] class Mailboxes(
     } else if (hasMailboxRequirement) {
       verifyRequirements(lookupByQueueType(mailboxRequirement))
     } else {
-      verifyRequirements(lookup(Mailboxes.DefaultMailboxId))
+      verifyRequirements(lookup(DefaultMailboxId))
     }
   }
 
@@ -156,6 +180,7 @@ private[akka] class Mailboxes(
       case null ⇒
         // It doesn't matter if we create a mailbox type configurator that isn't used due to concurrent lookup.
         val newConfigurator = id match {
+          // TODO RK remove these two for Akka 2.3
           case "unbounded" ⇒ UnboundedMailbox()
           case "bounded"   ⇒ new BoundedMailbox(settings, config(id))
           case _ ⇒
@@ -184,7 +209,7 @@ private[akka] class Mailboxes(
     }
   }
 
-  private val defaultMailboxConfig = settings.config.getConfig(Mailboxes.DefaultMailboxId)
+  private val defaultMailboxConfig = settings.config.getConfig(DefaultMailboxId)
 
   //INTERNAL API
   private def config(id: String): Config = {

akka-docs/rst/java/mailboxes.rst

@@ -79,8 +79,8 @@ dispatcher which will execute it. Then the mailbox is determined as follows:
 
 6. The default mailbox ``akka.actor.default-mailbox`` will be used.
 
-Which Configuration is pass to the Mailbox Type
------------------------------------------------
+Which Configuration is passed to the Mailbox Type
+-------------------------------------------------
 
 Each mailbox type is implemented by a class which extends :class:`MailboxType`
 and takes two constructor arguments: a :class:`ActorSystem.Settings` object and

akka-docs/rst/project/migration-guide-2.1.x-2.2.x.rst

@@ -85,12 +85,12 @@ Search                               Replace with
 If you need to convert from Java to ``scala.collection.immutable.Seq`` or ``scala.collection.immutable.Iterable`` you should use ``akka.japi.Util.immutableSeq(…)``,
 and if you need to convert from Scala you can simply switch to using immutable collections yourself or use the ``to[immutable.<collection-type>]`` method.
 
-ActorContext & ActorRefFactory dispatcher
+ActorContext & ActorRefFactory Dispatcher
 =========================================
 
 The return type of ``ActorContext``'s and ``ActorRefFactory``'s ``dispatcher``-method now returns ``ExecutionContext`` instead of ``MessageDispatcher``.
 
-Removed fallback to default dispatcher
+Removed Fallback to Default Dispatcher
 ======================================
 
 If deploying an actor with a specific dispatcher, e.g.
@@ -106,6 +106,17 @@ Akka 2.2 introduces the possibility to add dispatcher configuration to the
 The fallback was removed because in many cases its application was neither
 intended nor noticed.
 
+Changed Configuration Section for Dispatcher & Mailbox
+======================================================
+
+The mailbox configuration defaults moved from ``akka.actor.default-dispatcher``
+to ``akka.actor.default-mailbox``. You will not have to change anything unless
+your configuration overrides a setting in the default dispatcher section.
+
+The ``mailbox-type`` now requires a fully-qualified class name for the mailbox
+to use. The special words ``bounded`` and ``unbounded`` are retained for a
+migration period throughout the 2.2 series.
+
 API changes to FSM and TestFSMRef
 =================================
 

akka-docs/rst/scala/mailboxes.rst

@@ -79,8 +79,8 @@ dispatcher which will execute it. Then the mailbox is determined as follows:
 
 6. The default mailbox ``akka.actor.default-mailbox`` will be used.
 
-Which Configuration is pass to the Mailbox Type
------------------------------------------------
+Which Configuration is passed to the Mailbox Type
+-------------------------------------------------
 
 Each mailbox type is implemented by a class which extends :class:`MailboxType`
 and takes two constructor arguments: a :class:`ActorSystem.Settings` object and

akka-testkit/src/main/scala/akka/testkit/CallingThreadDispatcher.scala

@@ -340,7 +340,7 @@ class CallingThreadMailbox(_receiver: akka.actor.Cell, val mailboxType: MailboxT
       val qq = queue
       CallingThreadDispatcherQueues(actor.system).gatherFromAllOtherQueues(this, qq)
       super.cleanUp()
-      qq.cleanUp(actor.self, actor.systemImpl.deadLetterMailbox.messageQueue)
+      qq.cleanUp(actor.self, actor.dispatcher.mailboxes.deadLetterMailbox.messageQueue)
       q.remove()
     }
   }