private boolean dataChanged(List<? extends Pair<String, Icon>> newData) {
    final JComboBox<Pair<String, Icon>> comboBox = getComponent();
    final int size = comboBox.getItemCount();
    final List<Pair<String, Icon>> oldData = new ArrayList<>(size);
    for (int i = 0; i < size; i++) {
      oldData.add(comboBox.getItemAt(i));
    }

    if (myNullable) {
      final LinkedList<Pair<String, Icon>> list = new LinkedList<>(newData);
      list.addFirst(EMPTY);
      newData = list;
    }

    return !newData.equals(oldData);
  }
private boolean dataChanged(List<? extends Pair<String, Icon>> newData)