return ostream.toByteArray();
	public byte[] serialize() {		VariableByteOutputStream ostream = new VariableByteOutputStream();		try {			//ostream.writeUTF(fileName.substring(collection.getName().length() + 1));			ostream.writeLong(documentRootId);			((DocumentTypeImpl) docType).write(ostream);		} catch (IOException e) {			LOG.warn("io error while writing document data", e);			return null;		}		return ostream.toByteArray();	}