private static Result doSendViaGcm(String message, Sender sender,
      DeviceInfo deviceInfo) throws IOException {
    // Trim message if needed.
    if (message.length() > 1000) {
      message = message.substring(0, 1000) + "[...]";
    }

    // This message object is a Google Cloud Messaging object, it is NOT 
    // related to the MessageData class
    Message msg = new Message.Builder().addData("message", message).build();
    Result result = sender.send(msg, deviceInfo.getDeviceRegistrationID(),
        5);
    if (result.getMessageId() != null) {
      String canonicalRegId = result.getCanonicalRegistrationId();
      if (canonicalRegId != null) {
        endpoint.removeDeviceInfo(deviceInfo.getDeviceRegistrationID());
        deviceInfo.setDeviceRegistrationID(canonicalRegId);
        endpoint.insertDeviceInfo(deviceInfo);
      }
    } else {
      String error = result.getErrorCodeName();
      if (error.equals(Constants.ERROR_NOT_REGISTERED)) {
        endpoint.removeDeviceInfo(deviceInfo.getDeviceRegistrationID());
      }
    }

    return result;
  }