Akka: How to combine OneForOneStrategy and AllForOneStrategy

If I define the supervisor strategy for an actor in Scala, how can I use both the OneForOneStrategy and the AllForOneStrategy? Is there a simple way to combine them or do I have to define a custom SupervisorStrategy? Here is an example:

class MyActor extends Actor {
  override val supervisorStrategy = OneForOneStrategy() {
    case _: NullPointerException  => Restart
    case _: FileNotFoundException => Restart // here I want to restart all children
    case _: Exception             => Escalate
  }
}

If I have to write my own supervisor strategy, how can I do this? I found no example for that.