/**
   * Get device registered status of a virtual array
   *
   * @param id the URN of a ViPR varray
   * @return the device registered status
   */
  public Boolean getDeviceRegistered(URI id) {
    String getFlag = String.format(INTERNAL_VARRAY_GET_REGISTERED, id.toString());
    WebResource rRoot = createRequest(getFlag);
    VirtualArrayInternalFlags resp = null;
    try {
      resp = addSignature(rRoot).get(VirtualArrayInternalFlags.class);
    } catch (UniformInterfaceException e) {
      _log.warn("could not get registered status of varray {}. Err:{}", id, e);
      if (e.getResponse().getStatus() == 404) {
        throw APIException.notFound.unableToFindEntityInURL(id);
      }
    }

    return resp.getDeviceRegistered();
  }