public Iterable<Object> startWithValidation(final Reader in, String namespace, String schemaSource) throws SAXException {
SchemaFactory factory = SchemaFactory.newInstance(XMLConstants.W3C_XML_SCHEMA_NS_URI);
try (InputStream mis = new CachedFile(schemaSource).getInputStream()) {
Schema schema = factory.newSchema(new StreamSource(mis));
ValidatorHandler validator = schema.newValidatorHandler();
validator.setContentHandler(parser);
validator.setErrorHandler(parser);
AddNamespaceFilter filter = new AddNamespaceFilter(namespace);
filter.setContentHandler(validator);