getWhenTerminated in akka 2.5.9

Akka
1

In Akka 2.5.12 there is a method:

https://doc.akka.io/japi/akka/2.5.12/akka/actor/ActorSystem.html#getWhenTerminated--

And this works

CompletionStage<Terminated> stage = system.getWhenTerminated();
stage.thenRun(() ->System.out.println( "--Master Actor System Terminated"));

For legacy purposes I need to use 2.5.9, but am confused on the first parameter, I would like to do something the same like this:

      Future<Terminated> fts = system.whenTerminated();
      fts.onComplete(
    	() -> System.out.println( "--Master actor system terminated"), 
        , system.dispatcher());
  1. Is this a viable option for 2.5.9
  2. What do I pass i for the first parameter?
2

I think the nicest option is to transform the Future into a CompletionStage using the scala-java8-compat library (you likely have it as a transitive dependency via Akka already) and then use that as you are used to with a Java lambda.

There’s a Java example in the tests transforming a future to a completion stage here: https://github.com/scala/scala-java8-compat/blob/master/src/test/java/scala/compat/java8/FutureConvertersTest.java#L57

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3

So in essence is the only difference of getWhenTerminated and whenTerminated is one returns a future, and the other a completion stage?

4

So in essence is the only difference of getWhenTerminated and whenTerminated is one returns a future, and the other a completion stage?

Correct, that’s the only difference; one is intended for Java users and the other for Scala users.

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