@Override
  public Content remove(final int index) {
    checkIndex(index, true);

    final Content old = elementData[index];
    removeParent(old);
    System.arraycopy(elementData, index + 1, elementData, index, size - index - 1);
    elementData[--size] = null; // Let gc do its work
    incModCount();
    return old;
  }
@Override
  public Content remove(final int index)