question: private static int gap ( ConstraintWidget widget1 , Direction direction1 , ConstraintWidget widget2 , Direction direction2 ) { switch ( direction1 ) { case NORTH : case WEST : return getPos ( widget1 , direction1 ) - getPos ( widget2 , direction2 ) ; case SOUTH : case EAST : return getPos ( widget2 , direction2 ) - getPos ( widget1 , direction1 ) ; } return 0 ; }
target:  Get the gap between two specific edges of widgets