public Object end(final String uri,
final String localName,
final ExtensibleXmlParser parser) throws SAXException {
final Element element = parser.endElementBuilder();
final ExistsDescr existsDescr = (ExistsDescr) parser.getCurrent();
if ( (existsDescr.getDescrs().size() != 1) && (existsDescr.getDescrs().get( 0 ).getClass() != PatternDescr.class) ) {
throw new SAXParseException( "<exists> can only have a single <pattern...> as a child element",
parser.getLocator() );
}
final ConditionalElementDescr parentDescr = (ConditionalElementDescr) parser.getParent();