public Set<UserDefinedAction> areGesturesRegistered(Collection<MouseGesture> gesture){
  Set<MouseGesture> collisions=new HashSet<>(actionMap.keySet());
  collisions.retainAll(gesture);
  Set<UserDefinedAction> output=new HashSet<>();
  for (  MouseGesture collision : collisions) {
    output.add(actionMap.get(collision));
  }
  return output;
}

public Set < UserDefinedAction > areGesturesRegistered ( Collection < MouseGesture > gesture ) { Set < MouseGesture > collisions = new HashSet < > ( actionMap . keySet ( ) ) ; collisions . retainAll ( gesture ) ; Set < UserDefinedAction > output = new HashSet < > ( ) ; for ( MouseGesture collision : collisions ) { output . add ( actionMap . get ( collision ) ) ; } return output ; }
check if any collision between the gestures set and the set of currently registered gestures
