日历中的星期一问题

 Calendar calendar = new GregorianCalendar() ;
        Date nowDate = new Date() ;
        calendar.setTime(nowDate);

        boolean isSunday =  calendar.getFirstDayOfWeek() == Calendar.SUNDAY ;
        //获取今天是星期的第几天
        int dayInWeek = calendar.get(Calendar.DAY_OF_WEEK) ;
        if (isSunday){
            dayInWeek = dayInWeek - 1 ;
            if (dayInWeek == 0){
                dayInWeek = 7 ;
            }
        }