if (validating && doctype != null) endElementValidationHook();
  private void readEndElement()    throws IOException, XMLStreamException  {    //System.err.println("readEndElement");    // pop element off stack    String expected = (String) stack.removeLast();    require(expected);    skipWhitespace();    require('>');    // Make element name available    buf.setLength(0);    buf.append(expected);  }