private void addPoint(Point point, Collidable collidable)
    {
        final Integer group = collidable.getGroup();
        if (!collidables.containsKey(group))
        {
            collidables.put(group, new HashMap<Point, Set<Collidable>>());
        }
        final Map<Point, Set<Collidable>> elements = collidables.get(group);
        if (!elements.containsKey(point))
        {
            elements.put(point, new HashSet<Collidable>());
        }
        elements.get(point).add(collidable);
    }
private void addPoint ( Point point , Collidable collidable ) { final Integer group = collidable . getGroup ( ) ; if ( ! collidables . containsKey ( group ) ) { collidables . put ( group , new HashMap < Point , Set < Collidable > > ( ) ) ; } final Map < Point , Set < Collidable > > elements = collidables . get ( group ) ; if ( ! elements . containsKey ( point ) ) { elements . put ( point , new HashSet < Collidable > ( ) ) ; } elements . get ( point ) . add ( collidable ) ; }
Add point. Create empty list of not existing.

@param point The point to remove.
@param collidable The associated collidable.