if (disabledIcon == null && activeIcon instanceof ImageIcon) disabledIcon = new ImageIcon(GrayFilter.createDisabledImage(((ImageIcon) activeIcon).getImage()));
if (disabledIcon == null && icon instanceof ImageIcon) disabledIcon = new ImageIcon(GrayFilter.createDisabledImage(((ImageIcon) icon) .getImage()));
  public Icon getDisabledIcon()  {    if (disabledIcon == null && activeIcon instanceof ImageIcon)      disabledIcon = new ImageIcon(GrayFilter.createDisabledImage(((ImageIcon) activeIcon).getImage()));    return disabledIcon;  }