code: public DTMIterator createDTMIterator(int whatToShow,
            DTMFilter filter, boolean entityReferenceExpansion)
    {
      return m_dtmManager.createDTMIterator(whatToShow, filter, entityReferenceExpansion);
    }
docs: Create a new <code>DTMIterator</code> based only on a whatToShow and
  a DTMFilter.  The traversal semantics are defined as the descendant
  access.
  
  @param whatToShow This flag specifies which node types may appear in
  the logical view of the tree presented by the iterator. See the
  description of <code>NodeFilter</code> for the set of possible
  <code>SHOW_</code> values.These flags can be combined using
  <code>OR</code>.
  @param filter The <code>NodeFilter</code> to be used with this
  <code>TreeWalker</code>, or <code>null</code> to indicate no filter.
  @param entityReferenceExpansion The value of this flag determines
  whether entity reference nodes are expanded.
  
  @return The newly created <code>NodeIterator</code>.