Scala 如何在参与者中停止Source.tick?
我有一个演员,每2秒产生一个Scala 如何在参与者中停止Source.tick?,scala,akka,akka-stream,Scala,Akka,Akka Stream,我有一个演员,每2秒产生一个未使用的。也许它没有任何意义,但它只是为了测试的目的 import akka.NotUsed import akka.actor.{Actor, ActorLogging, Props} import akka.stream.{ActorMaterializer, KillSwitches} import akka.stream.scaladsl.{Keep, Sink, Source} import com.sweetsoft.FsmSystem.{Add, Sta
未使用的。也许它没有任何意义,但它只是为了测试的目的
import akka.NotUsed
import akka.actor.{Actor, ActorLogging, Props}
import akka.stream.{ActorMaterializer, KillSwitches}
import akka.stream.scaladsl.{Keep, Sink, Source}
import com.sweetsoft.FsmSystem.{Add, StartTicker, StopTicker}
import scala.concurrent.duration._
object AddActor {
def props: Props = Props(new AddActor)
}
final class AddActor extends Actor with ActorLogging {
implicit val materilizer = ActorMaterializer()
private val consumer: NotUsed => Unit = _ =>
context.parent ! Add
private val runnable = Source.tick(2.second, 2.second, NotUsed)
.named("Ticker")
.toMat(Sink.foreach(consumer))(Keep.both)
override def receive: Receive = {
case StartTicker =>
runnable.run()
case StopTicker =>
}
}
当参与者收到消息StopTicker
时,我想停止流。然后通过StartTicker
,启动流
调用run()
方法,我将获得具体化的值cancelabel
,但无法在StopTicker
范围内访问
我该怎么办 您可以使用以下模式:
将其保存在变量中,但仅使用val
不可能,对吗?是的,在Actors
中使用var
很常见(这不是真正的功能)。只需确保您永远不会在消息处理之外访问它。比如不要关闭它,把它放在未来
。真的,或者最好用FSM
建立一个参与者
?我不知道它之间有什么关系。FSM有状态,所以它本质上是可变的。DSL所做的只是让您将对状态指示符本身的更改隐藏在API后面。我认为这在实践中并不重要。
final class AddActor extends Actor with ActorLogging {
import context._
implicit val materilizer: ActorMaterializer = ActorMaterializer()
private val consumer: NotUsed => Unit = _ =>
self ! Add //send Add to self rather than directly to context.parent
private val runnable = Source.tick(2.second, 2.second, NotUsed)
.named("Ticker")
.toMat(Sink.foreach(consumer))(Keep.both)
override def preStart(): Unit = { //start runnable on actor start
super.preStart()
runnable.run()
}
val running: Receive = { //when running ignore new StartTicker but handle StopTicker and Add
case StopTicker =>
become(paused)
case Add =>
context.parent ! Add
}
val paused: Receive = { //handle just StartTicker
case StartTicker =>
become(running)
}
override def receive: Receive = paused //initial receive is paused
}