Publish UnhandledMessage to EventStream

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

@@ -103,6 +103,11 @@ case class UnhandledMessageException(msg: Any, ref: ActorRef = null) extends Run
   override def fillInStackTrace() = this //Don't waste cycles generating stack trace
 }
 
+/**
+ * This message is published to the EventStream whenever an Actor receives a message it doesn't understand
+ */
+case class UnhandledMessage(@BeanProperty message: Any, @BeanProperty recipient: ActorRef)
+
 /**
  * Classes for passing status back to the sender.
  * Used for internal ACKing protocol. But exposed as utility class for user-specific ACKing protocols as well.
@@ -272,7 +277,7 @@ trait Actor {
   def unhandled(message: Any) {
     message match {
       case Terminated(dead) ⇒ throw new DeathPactException(dead)
-      case _                ⇒ throw new UnhandledMessageException(message, self)
+      case _                ⇒ context.system.eventStream.publish(UnhandledMessage(message, self))
     }
   }
 

akka-docs/scala/actors.rst

@@ -47,8 +47,8 @@ Please note that the Akka Actor ``receive`` message loop is exhaustive, which is
 different compared to Erlang and Scala Actors. This means that you need to
 provide a pattern match for all messages that it can accept and if you want to
 be able to handle unknown messages then you need to have a default case as in
-the example above. Otherwise an ``UnhandledMessageException`` will be
-thrown and the actor is restarted when an unknown message is received.
+the example above. Otherwise an ``akka.actor.UnhandledMessage(message, actor)`` will be
+published to the ``ActorSystem``'s ``EventStream``.
 
 Creating Actors with default constructor
 ----------------------------------------