Fixed bug in shutdown management of global event-based dispatcher

akka-core/src/main/scala/actor/Actor.scala

@@ -415,6 +415,10 @@ trait Actor extends TransactionManagement {
   def start: Actor = synchronized {
     if (_isShutDown) throw new IllegalStateException("Can't restart an actor that has been shut down with 'exit'")
     if (!_isRunning) {
+      if (messageDispatcher.isShutdown && 
+          messageDispatcher.isInstanceOf[Dispatchers.globalExecutorBasedEventDrivenDispatcher.type]) {
+        messageDispatcher.asInstanceOf[ExecutorBasedEventDrivenDispatcher].init
+      }
       messageDispatcher.register(this)
       messageDispatcher.start
       _isRunning = true

akka-core/src/main/scala/dispatch/ExecutorBasedEventDrivenDispatcher.scala

@@ -57,9 +57,8 @@ class ExecutorBasedEventDrivenDispatcher(_name: String) extends MessageDispatche
   @volatile private var active: Boolean = false
   
   val name: String = "event-driven:executor:dispatcher:" + _name
-
-  withNewThreadPoolWithLinkedBlockingQueueWithUnboundedCapacity.buildThreadPool
-  
+  init 
+    
   def dispatch(invocation: MessageInvocation) = if (active) {
     executor.execute(new Runnable() {
       def run = {
@@ -79,10 +78,14 @@ class ExecutorBasedEventDrivenDispatcher(_name: String) extends MessageDispatche
   }
 
   def shutdown = if (active) {
+    log.debug("Shutting down ThreadBasedDispatcher [%s]", name)
     executor.shutdownNow
     active = false
+    references.clear
   }
-
+  
   def ensureNotActive: Unit = if (active) throw new IllegalStateException(
     "Can't build a new thread pool for a dispatcher that is already up and running")
+
+  private[akka] def init = withNewThreadPoolWithLinkedBlockingQueueWithUnboundedCapacity.buildThreadPool
 }

akka-core/src/main/scala/dispatch/Reactor.scala

@@ -6,7 +6,7 @@ package se.scalablesolutions.akka.dispatch
 
 import java.util.List
 
-import se.scalablesolutions.akka.util.HashCode
+import se.scalablesolutions.akka.util.{HashCode, Logging}
 import se.scalablesolutions.akka.stm.Transaction
 import se.scalablesolutions.akka.actor.Actor
 
@@ -56,7 +56,7 @@ trait MessageInvoker {
   def invoke(message: MessageInvocation)
 }
 
-trait MessageDispatcher {
+trait MessageDispatcher extends Logging {
   protected val references = new ConcurrentHashMap[String, Actor]  
   def dispatch(invocation: MessageInvocation)
   def start
@@ -64,6 +64,7 @@ trait MessageDispatcher {
   def register(actor: Actor) = references.put(actor.uuid, actor)
   def unregister(actor: Actor) = references.remove(actor.uuid)
   def canBeShutDown: Boolean = references.isEmpty
+  def isShutdown: Boolean
 }
 
 trait MessageDemultiplexer {

akka-core/src/main/scala/dispatch/ReactorBasedSingleThreadEventDrivenDispatcher.scala

@@ -36,6 +36,8 @@ class ReactorBasedSingleThreadEventDrivenDispatcher(name: String) extends Abstra
     selectorThread.start
   }
 
+  def isShutdown = !active
+
   class Demultiplexer(private val messageQueue: ReactiveMessageQueue) extends MessageDemultiplexer {
 
     private val selectedQueue: List[MessageInvocation] = new LinkedList[MessageInvocation]

akka-core/src/main/scala/dispatch/ThreadBasedDispatcher.scala

@@ -39,9 +39,13 @@ class ThreadBasedDispatcher private[akka] (val name: String, val messageHandler:
     selectorThread.start
   }
                        
+  def isShutdown = !active
+
   def shutdown = if (active) {
+    log.debug("Shutting down ExecutorBasedEventDrivenDispatcher [%s]", name)
     active = false
     selectorThread.interrupt
+    references.clear
   }
 }
 

akka-core/src/main/scala/dispatch/ThreadPoolBuilder.scala

@@ -28,6 +28,8 @@ trait ThreadPoolBuilder {
 
   protected var executor: ExecutorService = _
 
+  def isShutdown = executor.isShutdown
+
   def buildThreadPool = synchronized {
     ensureNotActive
     inProcessOfBuilding = false