java获取指定日期所在周的第一天和最后一天

java获取指定日期所在周的第一天和最后一天

第一种方法

public static String getFirstAndLastOfWeek(String dataStr) throws ParseException {
        Calendar cal = Calendar.getInstance();

        cal.setTime(new SimpleDateFormat("yyyy-MM-dd").parse(dataStr));

        int d = 0;
        if (cal.get(Calendar.DAY_OF_WEEK) == 1) {
            d = -6;
        } else {
            d = 2 - cal.get(Calendar.DAY_OF_WEEK);
        }
        cal.add(Calendar.DAY_OF_WEEK, d);
        // 所在周开始日期
        String data1 = new SimpleDateFormat("yyyy/MM/dd").format(cal.getTime());
        cal.add(Calendar.DAY_OF_WEEK, 6);
        // 所在周结束日期
        String data2 = new SimpleDateFormat("yyyy/MM/dd").format(cal.getTime());
        return data1 + "-" + data2;

    }

第二种方法

public static String getFirstAndLastOfWeek(int date) throws ParseException {
        Date InputDate = new SimpleDateFormat("yyyyMMdd").parse(String.valueOf(20140101));
        Calendar cDate = Calendar.getInstance();
        cDate.setFirstDayOfWeek(Calendar.MONDAY);
        cDate.setTime(InputDate);

        Calendar firstDate = Calendar.getInstance();

        firstDate.setFirstDayOfWeek(Calendar.MONDAY);
        firstDate.setTime(InputDate);

        Calendar lastDate = Calendar.getInstance();
        lastDate.setFirstDayOfWeek(Calendar.MONDAY);
        lastDate.setTime(InputDate);

        if (cDate.get(Calendar.WEEK_OF_YEAR) == 1 && cDate.get(Calendar.MONTH) == 11) {
            firstDate.set(Calendar.YEAR, cDate.get(Calendar.YEAR) + 1);
            lastDate.set(Calendar.YEAR, cDate.get(Calendar.YEAR) + 1);
        }

        int typeNum = cDate.get(Calendar.WEEK_OF_YEAR);
        System.out.println(typeNum);

        firstDate.set(Calendar.WEEK_OF_YEAR, typeNum);
        firstDate.set(Calendar.DAY_OF_WEEK, Calendar.MONDAY);
        // 所在周开始日期
        String beginDate = new SimpleDateFormat("yyyy/MM/dd").format(firstDate.getTime());
        System.out.println(beginDate);

        lastDate.set(Calendar.WEEK_OF_YEAR, typeNum);
        lastDate.set(Calendar.DAY_OF_WEEK, Calendar.SUNDAY);
        // 所在周结束日期
        String endDate = new SimpleDateFormat("yyyy-MM-dd").format(lastDate.getTime());
        System.out.println(endDate);
        return beginDate + "-" + endDate;
    }