if (!isName(localName)) throw new IllegalArgumentException("illegal Name: " + localName);
  public void writeStartElement(String localName)    throws XMLStreamException  {    try      {        endStartElement();        namespaces.pushContext();                writer.write('<');        writer.write(localName);                elements.addLast(new String[] { null, localName });        inStartElement = true;      }    catch (IOException e)      {        XMLStreamException e2 = new XMLStreamException(e);        e2.initCause(e);        throw e2;      }  }