获取日期段的时间差

         String ss = "2019-02-05";
         String s = "2019-02-10";
         Date a = null;
         Date b = null;
        SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");
        try {
           a = sdf.parse(s);
           b = sdf.parse(ss);
           
        } catch (ParseException e) {
            e.printStackTrace();
        }
        long day = Math.abs((  a.getTime() -   b.getTime()) / (24 * 60 * 60 * 1000));

结果5