code: private static void validateRELS(PID pid, String dsId, InputStream content)
              throws ValidationException {
          logger.debug("Validating " + dsId + " datastream");
          new RelsValidator().validate(pid, dsId, content);
          logger.debug(dsId + " datastream is valid");
      }
docs: validate relationships datastream
  @param pid
  @param dsId
  @param content
  @throws ValidationException