public void addSteps(final Iterator<? extends IStep> steps){
  if (steps == null)   throw new IllegalArgumentException();
  while (steps.hasNext()) {
    addStep(steps.next());
  }
}

public void addSteps ( final Iterator < ? extends IStep > steps ) { if ( steps == null ) throw new IllegalArgumentException ( ) ; while ( steps . hasNext ( ) ) { addStep ( steps . next ( ) ) ; } }
adds the steps to the program .
