code: public void paint(Paintable paintable, Object group, MapContext context) {
  		Circle circle = (Circle) paintable;
  		context.getVectorContext().drawCircle(group, circle.getId(), circle.getPosition(), circle.getRadius(),
  				circle.getStyle());
  	}
docs: The actual painting function. Draws the circles with the object's id.
  
  @param paintable
  A {@link Circle} object.
  @param group
  The group where the object resides in (optional).
  @param context
  A MapContext object, responsible for actual drawing.