JColorChooserのRGB色選択JRadioButtonにMnemonicを設定する

JColorChooser cc = new JColorChooser();
cc.setColor(label.getBackground());
AbstractColorChooserPanel rgbChooser = getRgbChooser(cc);
if (rgbChooser != null) {
  AbstractColorChooserPanel[] panels = cc.getChooserPanels();
  List<AbstractColorChooserPanel> choosers = new ArrayList<>(Arrays.asList(panels));
  List<String> rgbKey = Arrays.asList("rgbRed", "rgbGreen", "rgbBlue");
  String fmt = "ColorChooser.%sText";
  List<String> rgbList = Arrays.asList(
      UIManager.getString(String.format(fmt, rgbKey.get(0)), rgbChooser.getLocale()),
      UIManager.getString(String.format(fmt, rgbKey.get(1)), rgbChooser.getLocale()),
      UIManager.getString(String.format(fmt, rgbKey.get(2)), rgbChooser.getLocale()));
  SwingUtils.descendants(rgbChooser)
      .filter(JRadioButton.class::isInstance)
      .map(JRadioButton.class::cast)
      .forEach(r -> {
        String txt = r.getText();
        int idx = rgbList.indexOf(txt);
        if (idx >= 0) {
          String key = String.format("ColorChooser.%sMnemonic", rgbKey.get(idx));
          int mnemonic = getInteger(rgbChooser, key);
          if (mnemonic > 0) {
            r.setMnemonic(Character.toChars(mnemonic)[0]);
            mnemonic = getInteger(this, key + "Index");
            if (mnemonic >= 0) {
              r.setDisplayedMnemonicIndex(mnemonic);
            }
          }
        }
      });
  cc.setChooserPanels(choosers.toArray(new AbstractColorChooserPanel[0]));
}