code: public Node item(int index) {
          int handle=m_firstChild;
          while(--index>=0 && handle!=DTM.NULL) {
              handle=m_parentDTM.getNextSibling(handle);
          }
          if (handle == DTM.NULL) {
              return null;
          }
          return m_parentDTM.getNode(handle);
      }
docs: Returns the <code>index</code>th item in the collection. If
  <code>index</code> is greater than or equal to the number of nodes in
  the list, this returns <code>null</code>.
  @param index Index into the collection.
  @return The node at the <code>index</code>th position in the
  <code>NodeList</code>, or <code>null</code> if that is not a valid
  index.