docs: private Optional<JsonWebKeySet> buildJsonWebKeySet() {
          try {
              LOGGER.debug("Loading default JSON web key from [{}]", this.jwksFile);
              if (this.jwksFile != null) {
                  LOGGER.debug("Retrieving default JSON web key from [{}]", this.jwksFile);
                  val jsonWebKeySet = buildJsonWebKeySet(this.jwksFile);
  
                  if (jsonWebKeySet == null || jsonWebKeySet.getJsonWebKeys().isEmpty()) {
                      LOGGER.warn("No JSON web keys could be found");
                      return Optional.empty();
                  }
                  val badKeysCount = jsonWebKeySet.getJsonWebKeys().stream().filter(k ->
                      StringUtils.isBlank(k.getAlgorithm())
                          && StringUtils.isBlank(k.getKeyId())
                          && StringUtils.isBlank(k.getKeyType())).count();
  
                  if (badKeysCount == jsonWebKeySet.getJsonWebKeys().size()) {
                      LOGGER.warn("No valid JSON web keys could be found");
                      return Optional.empty();
                  }
  
                  val webKey = getJsonSigningWebKeyFromJwks(jsonWebKeySet);
                  if (webKey.getPrivateKey() == null) {
                      LOGGER.warn("JSON web key retrieved [{}] has no associated private key", webKey.getKeyId());
                      return Optional.empty();
                  }
                  return Optional.of(jsonWebKeySet);
              }
          } catch (final Exception e) {
              LOGGER.debug(e.getMessage(), e);
          }
          return Optional.empty();
      }