code: @Override
      public List<String> buildRequestUrl(final String resourceUri, final Endpoint endpoint) {
          LOGGER.debug("Processing: " + resourceUri);
          Objects.requireNonNull(resourceUri);
          try {
              final Optional<String> nonRdfSourceDescUri =
                      getNonRDFSourceDescribedByUri(resourceUri);
              if ( nonRdfSourceDescUri.isPresent() ) {
                  return Collections.singletonList(nonRdfSourceDescUri.get());
              }
          } catch (final IOException ex) {
              throw new UncheckedIOException(ex);
          }
          return Collections.singletonList(resourceUri);
      }
docs: /*
  Return the describedBy URL for NonRdfSource resources. Return the resourseUri otherwise.