code: Map<String, Object> callForJsonObjectMap(final String host, final int port,
        final String path, final List<Pair<String, String>> paramList) throws IOException {
      final String responseString =
          callForJsonString(host, port, path, paramList);
  
      @SuppressWarnings("unchecked") final Map<String, Object> jsonResponse =
          (Map<String, Object>) JSONUtils.parseJSONFromString(responseString);
      final String error = (String) jsonResponse.get(ConnectorParams.RESPONSE_ERROR);
      if (error != null) {
        throw new IOException(error);
      }
      return jsonResponse;
    }
docs: /*
  Call executor and return json object map.