using remote actors - fixed

test.scala

import akka.actor.{Props, ActorRef, Actor, ActorSystem}
import TestActors._
import com.typesafe.config.ConfigFactory


object MainServer extends App {
  start(asServer = true)
}

object MainClient extends App {
  start(asServer = false)
}

object TestActors {
  def start(asServer: Boolean) {
    val system = ActorSystem("System", ConfigFactory.parseString(config(asServer)))
    //    val server = system.actorOf(Props[ServerActor], "ServerActor")
    val server = if (asServer) {
      system.actorOf(Props[ServerActor], "ServerActor")
    } else {
      system.actorFor("akka://System@localhost:" + serverPort + "/user/ServerActor")
    }
    val client = system.actorOf(Props[ClientActor])
    server !('sub, client)
    while (true) {
      server ! 'pub
      Console.readLine()
    }
  }

  val ports = 2553 :: 2554 :: Nil
  val serverPort = ports(0)

  def config(asServer: Boolean): String = {
    """
      akka {
      remote {
      transport = "akka.remote.netty.NettyRemoteTransport"
      netty {
        hostname = "localhost"
        port = """ + (if (asServer) serverPort else ports(1)) + """
          }
       }
       actor {
           provider = "akka.remote.RemoteActorRefProvider"
       }
    }
    """
  }

  class ServerActor extends Actor {
    override def preStart() {
      println("Starting ServerActor")
    }

    var clients = List[ActorRef]()

    protected def receive = {
      case ('sub, sender: ActorRef) => clients ::= sender
      case 'pub => clients.foreach(_ ! 'hello)
    }
  }

  class ClientActor extends Actor {
    protected def receive = {
      case m => println(m)
    }
  }

}

how to have ServerActor be created only in jvm running MainServer ?

using akka 2.0
is this possible without using asServer variable and only by changing configuration?

The code looks adequate for solving the problem which I can derive from what the code does. If you are unhappy, you should state which requirements this violates, i.e. what you really want to achieve. In the end you’ll have to start different jobs for Client and Server, no matter how you configure them. Possibilities include: different config files, system properties, querying an external config source, checking the hostname, …

Thanks, Roland. My main concern is tight coupling to the way actor is created or looked up, which i'd like to resolve via configuration (akin to dependency injection). Please see my post on ml.