code: public void startDocument() throws SAXException
    {
  
      int doc = addNode(DTM.DOCUMENT_NODE,
                        DTM.DOCUMENT_NODE,
                        DTM.NULL, DTM.NULL, 0, true);
  
      m_parents.push(doc);
      m_previous = DTM.NULL;
  
      m_contextIndexes.push(m_prefixMappings.size());  // for the next element.
    }
docs: Receive notification of the beginning of the document.
  
  @throws SAXException Any SAX exception, possibly
  wrapping another exception.
  @see org.xml.sax.ContentHandler#startDocument