Implement a simple Akka app in Scala, and implement 2 processor Actors, improve the design

SimpleDesign

package foo

import akka.actor.{Actor, ActorSystem} 

/** 
 * Implement a simple application in Akka and Scala:
 * 
 * Don't worry about spending too much time on it, or
 * everything being perfect if you are not yet familiar...
 * I just want to see how you think and what you might know,
 * but if you want to show me some sweet code, go for it. 
 */
class SimpleDesign extends App {

  implicit val system = ActorSystem("example")
 
  // TODO create 2 instances of a Processor Actor - you can decide what they process


  // TODO send event message to one actor


  // TODO send event message to the other actor, and receive response back


  // TODO insure everything has been processed


  // then shutdown
  system.shutdown()
}


sealed trait EventMessage

case class Ping(msg: Any) extends EventMessage

case class Pong(msg: Any) extends EventMessage


/**
 * TODO refactor the two Processor designs for any code reuse, templating, etc:
 *
 *
 * Implement some simple processing
 */
class ProcessorA extends Actor {
  /**
   * TODO complete the actor receive cases
   */
  def receive = {
    case todo =>
    // TODO process received data
    // TODO return outcome to sender
  }
}

/**
 * TODO ProcessorB must processes input differently than ProcessorA
 */
class ProcessorB extends Actor {
  /**
   * TODO complete the actor receive cases
   */
  def receive = {
    case todo =>
      // TODO process received data
      // TODO return outcome to sender
  }
}