private static String resolveMessage(Locale locale, String key, Object[] args) {
        if (locale == null) {
            locale = new Locale("zh_CN");
        }
        try {
            return messageSource.getMessage(key, args, locale);
        } catch (Throwable t) {
            logger.error("i18n error, message not found by key :" + key, t);
            return key;
        }
    }
@author Robert HG (254963746@qq.com) on 3/9/16.
lts-admin/src/main/java/com/github/ltsopensource/admin/support/I18nManager.java