找不到参数系统的隐含值:akka.actor.ActorSystem

Question

我正在为Akka Actor创建一个单元测试用例TestActorRef.

def actorRefFactory = context
        implicit def executionContext = actorRefFactory.dispatcher
        implicit val OutputActor = actorRefFactory.actorOf(Props[OutputActor], "OutputActor")

        val actorRef = TestActorRef[OutputActor]
        val actor = actorRef.underlyingActor

在创建actorRef时出现以下错误:

- could not find implicit value for parameter system: akka.actor.ActorSystem
    - not enough arguments for method apply: (implicit t: 
     scala.reflect.ClassTag[org.musigma.muhpc.OutputActor], implicit system: 
     akka.actor.ActorSystem)akka.testkit.TestActorRef[org.musigma.muhpc.OutputActor] in object 
     TestActorRef. Unspecified value parameter system.

我对此很新.请帮助.

Answer 1

演员TestActorRef或实际真实实例的所有实例都需要ActorSystem驻留.实例化和启动actor(再次,测试或其他)的方法需要implicit ActorSystem在范围内,以便创建该actor的底层代码知道放置它的位置.

因此,考虑到这一点,您只需要确保在测试代码的开头添加一行代码:

implicit val system = ActorSystem()