Merge pull request #1157 from akka/wip-2800-no-null-msg-master-patriknw

Add fail fast checks to prevent null message, see #2800

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

@@ -452,6 +452,7 @@ private[akka] class EmptyLocalActorRef(override val provider: ActorRefProvider,
   }
 
   override def !(message: Any)(implicit sender: ActorRef = Actor.noSender): Unit = message match {
+    case null ⇒ throw new InvalidMessageException("Message is null")
     case d: DeadLetter ⇒
       specialHandle(d.message) // do NOT form endless loops, since deadLetters will resend!
     case _ if !specialHandle(message) ⇒
@@ -480,6 +481,7 @@ private[akka] class DeadLetterActorRef(_provider: ActorRefProvider,
                                        _eventStream: EventStream) extends EmptyLocalActorRef(_provider, _path, _eventStream) {
 
   override def !(message: Any)(implicit sender: ActorRef = this): Unit = message match {
+    case null          ⇒ throw new InvalidMessageException("Message is null")
     case d: DeadLetter ⇒ if (!specialHandle(d.message)) eventStream.publish(d)
     case _ ⇒ if (!specialHandle(message))
       eventStream.publish(DeadLetter(message, if (sender eq Actor.noSender) provider.deadLetters else sender, this))

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

@@ -386,6 +386,7 @@ class LocalActorRefProvider private[akka] (
     override def isTerminated: Boolean = stopped.isOn
 
     override def !(message: Any)(implicit sender: ActorRef = Actor.noSender): Unit = stopped.ifOff(message match {
+      case null                            ⇒ throw new InvalidMessageException("Message is null")
       case Failed(ex, _) if sender ne null ⇒ { causeOfTermination = Some(ex); sender.asInstanceOf[InternalActorRef].stop() }
       case NullMessage                     ⇒ // do nothing
       case _                               ⇒ log.error(this + " received unexpected message [" + message + "]")

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

@@ -91,7 +91,6 @@ private[akka] trait Dispatch { this: ActorCell ⇒
   def sendMessage(msg: Envelope): Unit =
     try {
       val m = msg.message.asInstanceOf[AnyRef]
-      if (m eq null) throw new InvalidMessageException("Message is null")
       if (system.settings.SerializeAllMessages && !m.isInstanceOf[NoSerializationVerificationNeeded]) {
         val s = SerializationExtension(system)
         s.deserialize(s.serialize(m).get, m.getClass).get

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

@@ -20,8 +20,10 @@ import scala.util.control.NonFatal
 final case class Envelope private (val message: Any, val sender: ActorRef)
 
 object Envelope {
-  def apply(message: Any, sender: ActorRef, system: ActorSystem): Envelope =
+  def apply(message: Any, sender: ActorRef, system: ActorSystem): Envelope = {
+    if (message == null) throw new InvalidMessageException("Message is null")
     new Envelope(message, if (sender ne Actor.noSender) sender else system.deadLetters)
+  }
 }
 
 /**

akka-actor/src/main/scala/akka/event/Logging.scala

@@ -720,7 +720,10 @@ object Logging {
     val path: ActorPath = new RootActorPath(Address("akka", "all-systems"), "/StandardOutLogger")
     def provider: ActorRefProvider = throw new UnsupportedOperationException("StandardOutLogger does not provide")
     override val toString = "StandardOutLogger"
-    override def !(message: Any)(implicit sender: ActorRef = Actor.noSender): Unit = print(message)
+    override def !(message: Any)(implicit sender: ActorRef = Actor.noSender): Unit = {
+      if (message == null) throw new InvalidMessageException("Message is null")
+      print(message)
+    }
   }
 
   val StandardOutLogger = new StandardOutLogger

akka-actor/src/main/scala/akka/pattern/AskSupport.scala

@@ -193,12 +193,14 @@ private[akka] final class PromiseActorRef private (val provider: ActorRefProvide
 
   override def !(message: Any)(implicit sender: ActorRef = Actor.noSender): Unit = state match {
     case Stopped | _: StoppedWithPath ⇒ provider.deadLetters ! message
-    case _ ⇒ if (!(result.tryComplete(
-      message match {
-        case Status.Success(r) ⇒ Success(r)
-        case Status.Failure(f) ⇒ Failure(f)
-        case other             ⇒ Success(other)
-      }))) provider.deadLetters ! message
+    case _ ⇒
+      if (message == null) throw new InvalidMessageException("Message is null")
+      if (!(result.tryComplete(
+        message match {
+          case Status.Success(r) ⇒ Success(r)
+          case Status.Failure(f) ⇒ Failure(f)
+          case other             ⇒ Success(other)
+        }))) provider.deadLetters ! message
   }
 
   override def sendSystemMessage(message: SystemMessage): Unit = message match {

akka-remote/src/main/scala/akka/remote/RemoteActorRefProvider.scala

@@ -355,8 +355,10 @@ private[akka] class RemoteActorRef private[akka] (
 
   def sendSystemMessage(message: SystemMessage): Unit = try remote.send(message, None, this) catch handleException
 
-  override def !(message: Any)(implicit sender: ActorRef = Actor.noSender): Unit =
+  override def !(message: Any)(implicit sender: ActorRef = Actor.noSender): Unit = {
+    if (message == null) throw new InvalidMessageException("Message is null")
     try remote.send(message, Option(sender), this) catch handleException
+  }
 
   def start(): Unit = if (props.isDefined && deploy.isDefined) provider.useActorOnNode(path, props.get, deploy.get, getParent)