throw new DomEx(DomEx.NAMESPACE_ERR,
throw new DomDOMException(DOMException.NAMESPACE_ERR,
  public Element createElementNS(String namespaceURI, String name)  {    if (checkingCharacters)      {        checkNCName(name, "1.1".equals(version));      }        if ("".equals(namespaceURI))      {        namespaceURI = null;      }    if (name.startsWith("xml:"))      {        if (namespaceURI != null            && !XMLConstants.XML_NS_URI.equals(namespaceURI))          {            throw new DomEx(DomEx.NAMESPACE_ERR,                            "xml namespace is always " +                            XMLConstants.XML_NS_URI, this, 0);          }        namespaceURI = XMLConstants.XML_NS_URI;      }    else if (XMLConstants.XMLNS_ATTRIBUTE.equals(name) ||             name.startsWith("xmlns:"))      {        throw new DomEx(DomEx.NAMESPACE_ERR,                        "xmlns is reserved", this, 0);      }    else if (namespaceURI == null && name.indexOf(':') != -1)      {        throw new DomEx(DomEx.NAMESPACE_ERR,                        "prefixed name '" + name + "' needs a URI", this, 0);      }        Element  element = new DomElement(this, namespaceURI, name);    defaultAttributes(element, name);    return element;  }