code: public void setBarBackgroundColor(final Color COLOR) {
          if (null == barBackgroundColor) {
              _barBackgroundColor = COLOR;
              fireUpdateEvent(REDRAW_EVENT);
          } else {
              barBackgroundColor.set(COLOR);
          }
      }
docs: Returns the color that will be used to colorize the bar background of
  the gauge (if it has a bar).
  
  @param COLOR