m_dtmRoot = root; m_xctxt = xctxt; m_dtm = xctxt.getDTM(root);
initDTM(root, xctxt);
  public XRTreeFrag(int root, XPathContext xctxt, ExpressionNode parent)  {    super(null);        // Obviously, this constructor should be avoided when possible.    exprSetParent(parent);    m_dtmRoot = root;    m_xctxt = xctxt;    m_dtm = xctxt.getDTM(root);  }