code: protected Map<String, Object> performRequestObject(String url,
  			Map<String, String> additionalHeaders) throws IOException {
  		Response response = performRequest(url, additionalHeaders);
  		try (InputStream is = response.getInputStream()) {
  			return parseResponseObject(response);
  		}
  	}
docs: Performs a request
  @param url the URL to query
  @param additionalHeaders additional HTTP request headers (may be null)
  @return the parsed response
  @throws IOException if the request was not successful