Typed messages in akka

Question

Akka framework recommends using typed actor only for interacting with external code. However, standard actors from akka are untyped. Is there any better way to create type safe actors? Are there some other actor frameworks or type safe wrappers around akka?

Answer 1

If you really want actors with static typing, then you might as well go ahead and use typed actors throughout your code. This is strongly discouraged for a couple of reasons.

1.) You run the risk of your system degenerating into a bunch of RPCs. An actor's receive method makes it pretty obvious that the whole thing is about message passing, much less so if you're just calling methods on a typed actor.

2.) An actor just really doesn't have a type. While it's running, the messages an actor is able to process may change depending on what state is in, as may what it does with those messages. This is an excellent way of modeling a lot of protocols, and Akka actors have first class support for it with FSMs.

So if you really want to do it, you're free to used typed actors everywhere and it'll work, but you should really think hard about the problem you're trying to solve before doing so.