public final boolean isModified() {
    List<T> items = getItems();
    OrderedSet<T> oldItems = helper.originalItems;
    if (items.size() != oldItems.size()) {
      return true;
    }
    else {
      for (int i = 0, size = items.size(); i < size; i++) {
        if (!items.get(i).equals(oldItems.get(i))) {
          return true;
        }
      }
    }
    return false;
  }
public final boolean isModified()