code: public static final Point subtract(Point p1, Point p2)
      {
          return new AbstractPoint(p1.getX() - p2.getX(), p1.getY() - p2.getY());
      }
docs: Returns a new Point(p1.x - p2.x, p1.y - p2.y)
  @param p1
  @param p2
  @return Returns a new Point(p1.x - p2.x, p1.y - p2.y)