根据日期获取周几，根据时间段获取几到周几

时间段获取几到周几"/>

根据日期获取周几，根据时间段获取几到周几

**根据日期获取几**public static String dateToWeek(String datetime) {SimpleDateFormat f = new SimpleDateFormat("yyyy-MM-dd");String[] weekDays = { "星期日", "星期一", "星期二", "星期三", "星期四", "星期五", "星期六" };Calendar cal = Calendar.getInstance(); // 获得一个日历Date datet = null;try {datet = f.parse(datetime);cal.setTime(datet);} catch (ParseException e) {// TODO Auto-generated catch blocke.printStackTrace();}int w = cal.get(Calendar.DAY_OF_WEEK) - 1; // 指示一个星期中的某天。if (w < 0)w = 0;return weekDays[w];}**根据时间段获取几**public static int dateToWeekNum(Date datetime) {Calendar cal = Calendar.getInstance(); // 获得一个日历cal.setTime(datetime);int w =  cal.get(Calendar.DAY_OF_WEEK)-2;if (w < 0)w = 6;return w;}**根据时间段获取几到周几**public static List<Integer> calcDateInterval(Date minDate, Date maxDate) {List<Integer> rangeList =new ArrayList<>();if(DateUtil.between(minDate, maxDate, DateUnit.DAY)>=7){int[] range ={0, 1, 2, 3, 4, 5, 6};rangeList = Arrays.stream(range).boxed().collect(Collectors.toList());}else {DateRange dateRange = DateUtil.range(minDate, maxDate, DateField.DAY_OF_WEEK);for (DateTime dateTime : dateRange) {rangeList.add(dateToWeekNum(dateTime));}}return rangeList;}