protected List<String> buildDefaultSMSReceivers(Receiver receiver) {
    List<String> smsReceivers = new ArrayList<String>();

    if (receiver != null) {
      smsReceivers.addAll(receiver.getPhones());
    }
    return smsReceivers;
  }
  protected List<String> buildDefaultWeixinReceivers(Receiver receiver) {
    List<String> weixinReceivers = new ArrayList<String>();

    if (receiver != null) {
      weixinReceivers.addAll(receiver.getWeixins());
    }
    return weixinReceivers;
  }
  protected List<String> buildDefaultMailReceivers(Receiver receiver) {
    List<String> mailReceivers = new ArrayList<String>();

    if (receiver != null) {
      mailReceivers.addAll(receiver.getEmails());
    }
    return mailReceivers;
  }