Sync response from Actor

[Yair Ogen]

I have an API that is synchronous - i.e. it need to return a result.

This API needs to run code that is not thread safe - i.e. must run in a single thread.

I'd like to bind once Actor to one Thread and have this actor serve all requests. Yes, I know I will create a bottleneck but this is what I need.

I couldn't find in Jumi how can I gt a sync response from an Actor. Only with callbacks.

Is there a solution to my problem?

[Esko Luontola]

There isn't yet support for synchronous responses, but there is a workaround: send the actor a CompletableFuture or similar as method parameter.

Then the caller code would be:

Future<String> f = new CompletableFuture<>();

actor.doSomething(f);

String result = f.get();

And the actor would be:

public void doSomething(CompletableFuture<String> result) {

    result.complete("the result");

}

I might later improve jumi-actors to support that with less boilerplate (so that you can return a Future from the actor method).