code: @Override
      protected String sendRequestForData(Token accessToken, String dataUrl) throws HttpException {
          final ProxyOAuthRequest request = new ProxyOAuthRequest(Verb.GET, dataUrl, this.proxyHost, this.proxyPort);
          if (this.connectTimeout != 0) {
              request.setConnectTimeout(this.connectTimeout, TimeUnit.MILLISECONDS);
          }
          if (this.readTimeout != 0) {
              request.setReadTimeout(this.readTimeout, TimeUnit.MILLISECONDS);
          }
          this.service.signRequest(accessToken, request);
          request.addHeader("Content-Type", "application/json");
          final Response response = request.send();
          final int code = response.getCode();
          final String body = response.getBody();
          if (code != 200) {
              throw new HttpException(code, body);
          }
          return body;
      }
docs: Calls any Globus endpoint that requires already being authenticated.
  Relies on {@link #internalInit() } to setup request signing.
  
  @param accessToken the access token to use when signing the request.
  @param dataUrl the endpoint to call.
  @return the response body.
  
  @throws HttpException if an error occurred calling the endpoint.