Remove ClusterEventBus and system.eventStream, see #2202

akka-cluster/src/main/scala/akka/cluster/Cluster.scala

@@ -103,8 +103,6 @@ class Cluster(system: ExtendedActorSystem, val failureDetector: FailureDetector)
   @volatile
   private[cluster] var _latestStats = ClusterStats()
 
-  private[cluster] val eventBus: ClusterEventBus = new ClusterEventBus
-
   // ========================================================
   // ===================== WORK DAEMONS =====================
   // ========================================================
@@ -167,7 +165,7 @@ class Cluster(system: ExtendedActorSystem, val failureDetector: FailureDetector)
       }
     }).withDispatcher(UseDispatcher), name = "clusterEventBusListener")
 
-    eventBus.subscribe(listener, classOf[ClusterDomainEvent])
+    subscribe(listener, classOf[ClusterDomainEvent])
     listener
   }
 
@@ -261,7 +259,12 @@ class Cluster(system: ExtendedActorSystem, val failureDetector: FailureDetector)
    * The `to` Class can be [[akka.cluster.ClusterEvent.ClusterDomainEvent]]
    * or subclass.
    */
-  def subscribe(subscriber: ActorRef, to: Class[_]): Unit = eventBus.subscribe(subscriber, to)
+  def subscribe(subscriber: ActorRef, to: Class[_]): Unit = system.eventStream.subscribe(subscriber, to)
+
+  /**
+   * Subscribe to cluster domain events.
+   */
+  def unsubscribe(subscriber: ActorRef): Unit = system.eventStream.unsubscribe(subscriber)
 
   /**
    * Try to join this cluster node with the node specified by 'address'.
@@ -299,7 +302,7 @@ class Cluster(system: ExtendedActorSystem, val failureDetector: FailureDetector)
       log.info("Cluster Node [{}] - Shutting down cluster Node and cluster daemons...", selfAddress)
 
       system.stop(clusterDaemons)
-      eventBus.unsubscribe(eventBusListener)
+      unsubscribe(eventBusListener)
       system.stop(eventBusListener)
 
       scheduler.close()

akka-cluster/src/main/scala/akka/cluster/ClusterDaemon.scala

@@ -8,6 +8,7 @@ import scala.concurrent.util.{ Deadline, Duration }
 import scala.concurrent.forkjoin.ThreadLocalRandom
 import akka.actor.{ Actor, ActorLogging, ActorRef, Address, Cancellable, Props, RootActorPath, PoisonPill, Scheduler }
 import akka.actor.Status.Failure
+import akka.event.EventStream
 import akka.routing.ScatterGatherFirstCompletedRouter
 import akka.util.Timeout
 import akka.pattern.{ AskTimeoutException, ask, pipe }
@@ -125,7 +126,6 @@ private[cluster] trait ClusterEnvironment {
   private[cluster] def selfAddress: Address
   private[cluster] def scheduler: Scheduler
   private[cluster] def seedNodes: IndexedSeq[Address]
-  private[cluster] def eventBus: ClusterEventBus
   private[cluster] def shutdown(): Unit
 }
 
@@ -808,17 +808,19 @@ private[cluster] final class ClusterCoreDaemon(environment: ClusterEnvironment)
   }
 
   def publishState(): Unit = {
-    environment.eventBus publish MembershipGossipChanged(latestGossip)
+    eventStream publish MembershipGossipChanged(latestGossip)
-    environment.eventBus publish InternalStatsChanged(stats)
+    eventStream publish InternalStatsChanged(stats)
   }
 
   def publishMembers(oldMembers: SortedSet[Member]): Unit = {
     val oldMembersStatus = oldMembers.map(m ⇒ (m.address, m.status))
     val newMembersStatus = latestGossip.members.map(m ⇒ (m.address, m.status))
     if (newMembersStatus != oldMembersStatus)
-      environment.eventBus publish MembersChanged(latestGossip.members)
+      eventStream publish MembersChanged(latestGossip.members)
   }
 
+  def eventStream: EventStream = context.system.eventStream
+
   def ping(p: Ping): Unit = sender ! Pong(p)
 }
 

akka-cluster/src/main/scala/akka/cluster/ClusterEventBus.scala

@@ -1,32 +0,0 @@
-/**
- * Copyright (C) 2009-2012 Typesafe Inc. <http://www.typesafe.com>
- */
-package akka.cluster
-
-import akka.event.ActorEventBus
-import akka.event.SubchannelClassification
-import akka.actor.ActorRef
-import akka.util.Subclassification
-
-/**
- * Changes to the Cluster are published to this local event bus
- * as [[akka.cluster.ClusterEvent.ClusterDomainEvent]] subclasses.
- */
-class ClusterEventBus extends ActorEventBus with SubchannelClassification {
-
-  type Event = AnyRef
-  type Classifier = Class[_]
-
-  protected implicit val subclassification = new Subclassification[Class[_]] {
-    def isEqual(x: Class[_], y: Class[_]) = x == y
-    def isSubclass(x: Class[_], y: Class[_]) = y isAssignableFrom x
-  }
-
-  protected def classify(event: AnyRef): Class[_] = event.getClass
-
-  protected def publish(event: AnyRef, subscriber: ActorRef) = {
-    if (subscriber.isTerminated) unsubscribe(subscriber)
-    else subscriber ! event
-  }
-
-}