计算两个时间的差值

        Date endTime = activity.getEndTime();
        Date startTime = new Date();
        Calendar startCalendar = Calendar.getInstance();
        startCalendar.setTime(startTime);
        Calendar endCalendar = Calendar.getInstance();
        endCalendar.setTime(endTime);
        Long endSecond = endCalendar.getTimeInMillis();
        Long startSecond = startCalendar.getTimeInMillis();
        Long balance = endSecond-startSecond;
        Integer s_day = 60*60*24*1000;
        Integer s_hour = 60*60*1000;
        Integer s_min = 60*1000;
        Long day = balance/s_day;//还剩多少天
        Long hour = (balance-day*s_day)/s_hour;//还剩多少小时
        Long min = (balance-day*s_day-hour*s_hour)/s_min;//还剩多少分钟
        Long sec = (balance-day*s_day-hour*s_hour-min*s_min)/1000;//还剩多少秒