private static int getSelectedIndex(ButtonGroup group) {
      final ButtonModel selection = group.getSelection();
      if (selection == null) return -1;
      final Enumeration<AbstractButton> buttons = group.getElements();
      for (int i = 0; buttons.hasMoreElements(); i++) {
        final AbstractButton button = buttons.nextElement();
        if (group.isSelected(button.getModel())) return i;
      }
      return -1;
    }
private static int getSelectedIndex(ButtonGroup group)