code: public void setKnobPosition(final Pos POSITION) {
          if (null == knobPosition) {
              _knobPosition = POSITION;
              fireUpdateEvent(RESIZE_EVENT);
          } else {
              knobPosition.set(POSITION);
          }
      }
docs: Defines the position of the knob in radial gauges. This
  position also defines where the needle will be placed.
  Dependent on the SkinType you can use the following values
  GaugeSkin  : CENTER
  HSkin      : TOP_CENTER, BOTTOM_CENTER
  VSkin      : CENTER_LEFT, CENTER_RIGHT
  QuarterSkin: TOP_RIGHT, BOTTOM_RIGHT, BOTTOM_LEFT, TOP_LEFT
  
  @param POSITION