public Object end(final String uri,
final String localName) throws SAXException {
final Configuration config = this.xmlPackageReader.endConfiguration();
final ExistsDescr existsDescr = (ExistsDescr) this.xmlPackageReader.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",
this.xmlPackageReader.getLocator() );
}
final LinkedList parents = this.xmlPackageReader.getParents();