From b600c517a1e7485bebf50c8246ce7205daa228d6 Mon Sep 17 00:00:00 2001 From: Will Sargent Date: Mon, 4 Sep 2017 07:31:43 -0700 Subject: [PATCH] Add customized NPE for null actor system (#23580) * Add customized NPE for null actor system * "system must not be null!" --- akka-actor/src/main/scala/akka/actor/Extension.scala | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/akka-actor/src/main/scala/akka/actor/Extension.scala b/akka-actor/src/main/scala/akka/actor/Extension.scala index 8855e07309..360701dca5 100644 --- a/akka-actor/src/main/scala/akka/actor/Extension.scala +++ b/akka-actor/src/main/scala/akka/actor/Extension.scala @@ -74,7 +74,9 @@ trait ExtensionId[T <: Extension] { /** * Returns an instance of the extension identified by this ExtensionId instance. */ - def apply(system: ActorSystem): T = system.registerExtension(this) + def apply(system: ActorSystem): T = { + java.util.Objects.requireNonNull(system, "system must not be null!").registerExtension(this) + } /** * Returns an instance of the extension identified by this ExtensionId instance.