Implementing Akka AbstractActor in Groovy produces compiler errors

Question

Groovy 2.4.7 here using the Akka Java API with Gradle coordinates: com.typesafe.akka:akka-actor_2.11:2.5.4 .

I'm trying to implement an AbstractActor and running into a potential conflict between the Java/Akka API and Groovy itself:

class MyActor extends AbstractActor {
    @Override
    Receive createReceive() {
        receiveBuilder()
            .match(DoSomething, message -> {
            // Implement message handler if message is of type DoSomething
            }).build()
    }
}

Produces the following compiler error:

" Groovy:expecting EOF, found ')' @ line 18, column 5. "

I think it has something to do with the -> operator used after message. Is there a fix or workaround for this in Groovy-land?

Answer 1

You've mixed up java's lambda expressions with groovy's closures. So it should be:

class MyActor extends AbstractActor {
    @Override
    Receive createReceive() {
        receiveBuilder()
            .match(DoSomething, { message ->
            // Implement message handler if message is of type DoSomething
            }).build()
    }
}

Please have a look here as well.