FieldPresenceValidation validation = settings.getFieldExistanceValidation();
if (validation.isRequired()) {
MappingUtils.validateMapping(fields, mapping, validation, log);
}
input = QueryBuilder.query(settings).fields(StringUtils.concatenate(fields, ",")).build(client, new ScrollReader(new JdkValueReader(), mapping));
}
return new TupleEntrySchemeIterator<Properties, ScrollQuery>(flowProcess, getScheme(), input, getIdentifier());
}