code: @Override
      public List<Object> loginRequest() {
          loadTokens();
  
          // If we got here, 'GET _session' failed, so there's no valid session cookie or ID token.
          IDToken = null;
          haveSessionCookie = false;
  
          String path;
          if (refreshToken != null)
              path = String.format(Locale.ENGLISH, "_oidc_refresh?refresh_token=%s",
                      URIUtils.encode(refreshToken));
          else if (authURL != null)
              path = String.format(Locale.ENGLISH, "_oidc_callback?%s",
                      authURL.getQuery());
          else
              path = "_oidc_challenge?offline=true";
          // Note: casting to Object makes Arrays.asList() return List<Object>
          return Arrays.asList("GET", (Object) path);
      }
docs: #pragma mark - LOGIN: