throws SAXException, PermissionDeniedException, EXistException,
throws SAXException, LockException, PermissionDeniedException, EXistException,
	public int xupdate(User user, String collectionName, String xupdate)			throws SAXException, PermissionDeniedException, EXistException,			XPathException {		DBBroker broker = null;		try {			broker = brokerPool.get(user);			Collection collection = broker.getCollection(collectionName);			if (collection == null)				throw new EXistException("collection " + collectionName						+ " not found");			DocumentSet docs = collection.allDocs(broker, new DocumentSet(),					true);			XUpdateProcessor processor = new XUpdateProcessor(broker, docs);			Modification modifications[] = processor.parse(new InputSource(					new StringReader(xupdate)));			long mods = 0;			for (int i = 0; i < modifications.length; i++) {				mods += modifications[i].process();				broker.flush();			}			return (int) mods;		} catch (ParserConfigurationException e) {			throw new EXistException(e.getMessage());		} catch (IOException e) {			throw new EXistException(e.getMessage());		} finally {			brokerPool.release(broker);		}	}