我遇到了一个扩展 Stash 的演员的问题，并且在简单的 ActorSystem 中使用 actorOf 实例化它时工作得非常好。现在我实际上想在我的程序中使用它们之前为我的存储演员编写一些测试。但是我想不出一种在我的测试套件中将 TestActorRef 与这个演员一起使用的方法。
有效的代码如下所示：
import akka.actor.{Stash, Actor, ActorSystem, Props}
import com.typesafe.config.ConfigFactory
object StashTest {
val config = ConfigFactory.parseString(
"""
|akka.actor.default-mailbox {
| mailbox-type = "akka.dispatch.UnboundedDequeBasedMailbox"
|}
""".stripMargin)
}
class StashTestActor extends Stash {
def receive: Actor.Receive = {
case "unstash" =>
unstashAll()
context become print
case msg => stash()
}
def print: Actor.Receive = {
case msg => println(s"Unstashed message: $msg")
}
}
val system = ActorSystem("stashSystem", StashTest.config)
val ref = system.actorOf(Props[StashTestActor])
ref ! "stash me"
ref ! "blah"
ref ! "unstash"
哪个打印
Unstashed message: stash me
Unstashed message: blah
但是，如果我尝试为这个演员编写一个 WordSpec 测试，它会给我留下一些令人讨厌的例外情况，我无法弄清楚他们希望我在我的代码中更改什么。
测试类看起来像这样
import akka.testkit.{TestActorRef, TestKit}
import akka.actor.{Stash, Actor, ActorSystem}
import org.scalatest.{WordSpecLike, MustMatchers}
import com.typesafe.config.ConfigFactory
class StashTestActor extends Stash {
def receive: Actor.Receive = {
case "unstash" =>
unstashAll()
context become print
case msg => stash()
}
def print: Actor.Receive = {
case msg => println(s"Unstashed message: $msg")
}
}
class StashTest extends TestKit(ActorSystem("testSystem", StashTest.config))
with WordSpecLike
with MustMatchers {
"A simple stashing actor" must {
val actorRef = TestActorRef[StashTestActor]
"stash messages" in {
actorRef ! "stash me!"
}
"unstash all messages" in {
actorRef ! "unstash"
}
}
}
object StashTest {
val config = ConfigFactory.parseString(
"""
|akka.actor.default-mailbox {
| mailbox-type = "akka.dispatch.UnboundedDequeBasedMailbox"
|}
""".stripMargin)
}
运行测试时，我得到以下在 TestActorRef 实例化期间引发的异常。
[ERROR] [08/20/2013 14:19:40.765] [testSystem-akka.actor.default-dispatcher-3] [akka://testSystem/user/$$a] Could not instantiate Actor
Make sure Actor is NOT defined inside a class/trait,
if so put it outside the class/trait, f.e. in a companion object,
OR try to change: 'actorOf(Props[MyActor]' to 'actorOf(Props(new MyActor)'.
akka.actor.ActorInitializationException: exception during creation
at akka.actor.ActorInitializationException$.apply(Actor.scala:218)
at akka.actor.ActorCell.create(ActorCell.scala:578)
at akka.actor.ActorCell.invokeAll$1(ActorCell.scala:425)
at akka.actor.ActorCell.systemInvoke(ActorCell.scala:447)
at akka.dispatch.Mailbox.processAllSystemMessages(Mailbox.scala:262)
at akka.testkit.CallingThreadDispatcher.process$1(CallingThreadDispatcher.scala:244)
at akka.testkit.CallingThreadDispatcher.runQueue(CallingThreadDispatcher.scala:284)
at akka.testkit.CallingThreadDispatcher.register(CallingThreadDispatcher.scala:153)
at akka.dispatch.MessageDispatcher.attach(AbstractDispatcher.scala:133)
at akka.actor.dungeon.Dispatch$class.start(Dispatch.scala:84)
at akka.actor.ActorCell.start(ActorCell.scala:338)
at akka.testkit.TestActorRef.<init>(TestActorRef.scala:50)
at akka.testkit.TestActorRef$.apply(TestActorRef.scala:141)
at akka.testkit.TestActorRef$.apply(TestActorRef.scala:137)
at akka.testkit.TestActorRef$.apply(TestActorRef.scala:146)
at akka.testkit.TestActorRef$.apply(TestActorRef.scala:144)
at stashActorTest.StashTest$$anonfun$1.apply$mcV$sp(StashTestActor.scala:29)
at stashActorTest.StashTest$$anonfun$1.apply(StashTestActor.scala:28)
at stashActorTest.StashTest$$anonfun$1.apply(StashTestActor.scala:28)
at org.scalatest.SuperEngine.registerNestedBranch(Engine.scala:613)
at org.scalatest.WordSpecLike$class.org$scalatest$WordSpecLike$$registerBranch(WordSpecLike.scala:120)
at org.scalatest.WordSpecLike$$anon$2.apply(WordSpecLike.scala:851)
at org.scalatest.words.MustVerb$StringMustWrapperForVerb$class.must(MustVerb.scala:189)
at org.scalatest.matchers.MustMatchers$StringMustWrapper.must(MustMatchers.scala:6167)
at stashActorTest.StashTest.<init>(StashTestActor.scala:28)
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:57)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
at java.lang.reflect.Constructor.newInstance(Constructor.java:526)
at java.lang.Class.newInstance(Class.java:374)
at org.scalatest.tools.Framework$ScalaTestTask.execute(Framework.scala:444)
at sbt.TestRunner.runTest$1(TestFramework.scala:84)
at sbt.TestRunner.run(TestFramework.scala:94)
at sbt.TestFramework$$anon$2$$anonfun$$init$$1$$anonfun$apply$8.apply(TestFramework.scala:224)
at sbt.TestFramework$$anon$2$$anonfun$$init$$1$$anonfun$apply$8.apply(TestFramework.scala:224)
at sbt.TestFramework$.sbt$TestFramework$$withContextLoader(TestFramework.scala:212)
at sbt.TestFramework$$anon$2$$anonfun$$init$$1.apply(TestFramework.scala:224)
at sbt.TestFramework$$anon$2$$anonfun$$init$$1.apply(TestFramework.scala:224)
at sbt.TestFunction.apply(TestFramework.scala:229)
at sbt.Tests$$anonfun$7.apply(Tests.scala:196)
at sbt.Tests$$anonfun$7.apply(Tests.scala:196)
at sbt.std.Transform$$anon$3$$anonfun$apply$2.apply(System.scala:45)
at sbt.std.Transform$$anon$3$$anonfun$apply$2.apply(System.scala:45)
at sbt.std.Transform$$anon$4.work(System.scala:64)
at sbt.Execute$$anonfun$submit$1$$anonfun$apply$1.apply(Execute.scala:237)
at sbt.Execute$$anonfun$submit$1$$anonfun$apply$1.apply(Execute.scala:237)
at sbt.ErrorHandling$.wideConvert(ErrorHandling.scala:18)
at sbt.Execute.work(Execute.scala:244)
at sbt.Execute$$anonfun$submit$1.apply(Execute.scala:237)
at sbt.Execute$$anonfun$submit$1.apply(Execute.scala:237)
at sbt.ConcurrentRestrictions$$anon$4$$anonfun$1.apply(ConcurrentRestrictions.scala:160)
at sbt.CompletionService$$anon$2.call(CompletionService.scala:30)
at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:334)
at java.util.concurrent.FutureTask.run(FutureTask.java:166)
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:471)
at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:334)
at java.util.concurrent.FutureTask.run(FutureTask.java:166)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
at java.lang.Thread.run(Thread.java:724)
Caused by: akka.actor.ActorInitializationException: Could not instantiate Actor
Make sure Actor is NOT defined inside a class/trait,
if so put it outside the class/trait, f.e. in a companion object,
OR try to change: 'actorOf(Props[MyActor]' to 'actorOf(Props(new MyActor)'.
at akka.actor.ActorInitializationException$.apply(Actor.scala:218)
at akka.testkit.TestActorRef$$anonfun$apply$2$$anonfun$apply$1.applyOrElse(TestActorRef.scala:148)
at akka.testkit.TestActorRef$$anonfun$apply$2$$anonfun$apply$1.applyOrElse(TestActorRef.scala:147)
at scala.runtime.AbstractPartialFunction.apply(AbstractPartialFunction.scala:33)
at scala.util.Failure$$anonfun$recover$1.apply(Try.scala:185)
at scala.util.Try$.apply(Try.scala:161)
at scala.util.Failure.recover(Try.scala:185)
at akka.testkit.TestActorRef$$anonfun$apply$2.apply(TestActorRef.scala:147)
at akka.testkit.TestActorRef$$anonfun$apply$2.apply(TestActorRef.scala:153)
at akka.actor.CreatorFunctionConsumer.produce(Props.scala:369)
at akka.actor.Props.newActor(Props.scala:323)
at akka.actor.ActorCell.newActor(ActorCell.scala:534)
at akka.actor.ActorCell.create(ActorCell.scala:560)
... 58 more
Caused by: java.lang.NullPointerException
at akka.actor.UnrestrictedStash$class.$init$(Stash.scala:82)
at stashActorTest.StashTestActor.<init>(StashTestActor.scala:9)
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:57)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
at java.lang.reflect.Constructor.newInstance(Constructor.java:526)
at akka.actor.ReflectiveDynamicAccess$$anonfun$createInstanceFor$2.apply(DynamicAccess.scala:78)
at scala.util.Try$.apply(Try.scala:161)
at akka.actor.ReflectiveDynamicAccess.createInstanceFor(DynamicAccess.scala:73)
... 64 more
我对不扩展 Stash 的演员使用 TestActorRefs 没有任何问题。所以我不知道这是配置错误还是我遗漏的其他东西。