java 獲取最近7天 最近今天的日期

private static  Date getDateAdd(int days){    SimpleDateFormat sf = new SimpleDateFormat("yyyy-MM-dd");    Calendar c = Calendar.getInstance();    c.add(Calendar.DAY_OF_MONTH, -days);   return c.getTime();}private static  List<String> getDaysBetwwen(int days){ //最近幾天日期    List<String> dayss = new ArrayList<>();    Calendar start = Calendar.getInstance();    start.setTime(getDateAdd(days));    Long startTIme = start.getTimeInMillis();    Calendar end = Calendar.getInstance();    end.setTime(new Date());    Long endTime = end.getTimeInMillis();    Long oneDay = 1000 * 60 * 60 * 24l;    Long time = startTIme;    while (time <= endTime) {        Date d = new Date(time);        DateFormat df = new SimpleDateFormat("yyyy-MM-dd");        System.out.println(df.format(d));        dayss.add(df.format(d));        time += oneDay;    }    return dayss;}