@Override
    public Attribute next() {
      if (modCount != expect) {
        throw new ConcurrentModificationException("ContentList was " +
                                                  "modified outside of this Iterator");
      }
      if (cursor >= size) {
        throw new NoSuchElementException("Iterated beyond the end of " +
                                         "the ContentList.");
      }
      canremove = true;
      return attributeData[cursor++];
    }
@Override
    public Attribute next()