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scalaasynchronousakkaactorinbox

Interact with Akka actor outside actors

I want to interact with Akka actors from my own thread. Currently, i do like so:

val res = Await.result(aref ? GroupReceive(fromRank), timeout.duration).asInstanceOf[T]

But I am unsure how this actually interacts with my thread? I wish for the receive to be asynchronous, i.e. I want to hang up the thread while receiving to allow for some other work to be done. I just recently read about Akka inbox system. inbox akka api

I think I recall that Await creates a new actor every time. What are the differences between await+ask and inbox, and can someone give me an example of how to create an inbox and use it to communicate with actors from "the outside" ?

EDIT Just to clarify, I don't want the same thread to continue working, I want it to stop hogging a cpu-core and leave other threads to work until it receives something, then wake up again.

Solution

  • As written in the Akka's Future documentation, using Await blocks current thread until awaiting for the result.

    Example

    import scala.concurrent.Await
import akka.pattern.ask
import akka.util.Timeout
import scala.concurrent.duration._

implicit val timeout = Timeout(5 seconds)
val future = actor ? msg // enabled by the “ask” import
val result = Await.result(future, timeout.duration).asInstanceOf[String]

    This will cause the current thread to block and wait for the Actor to 'complete' the Future with it's reply.

    Use With Actors