Best practice for defining multiple traits that add behavior to classes that implement a particular trait

Let's say I have a number trait

that adds some behavior to the extending classes Actor

.

Each requires a small subset of the Actor

. Is it ok for everyone to expand Actor

as follows?

trait A extends Actor {
  def doAThing = { ... }
}
trait B extends Actor {
  def doBThing = { ... }
}
trait C extends Actor {
  def doCThing = { ... }
}

class D extends Actor with A with B with C

      

        
        
        
      

    

Or does each trait define the methods it needs from Actor

as abstract methods, so that they are exposed by a final, concrete class that is the only one that then extends Actor

?