code: public static long dayDiffCurr(String before) {
          Date currDate = parseq(DF_DATE, sD(now()));
          Date beforeDate = parseq(DF_DATE, before);
          return (currDate.getTime() - beforeDate.getTime()) / 86400000;
  
      }
docs: 比较指定日期与当前日期的天差
  
  @param before
  指定的前应日期,格式yyyy-MM-dd
  @return 天差