question: 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 ; }
target:  Check if any collision between the gestures set and the set of currently registered gestures