code: public void addMessageNow(String message) {
      ActionMessages messages = (ActionMessages) now.get(Flash.MESSAGES);
      if (null == messages) {
        messages = new ActionMessages();
        now.put(Flash.MESSAGES, messages);
      }
      messages.getMessages().add(message);
    }
docs: 添加消息到本次请求
  
  @param message