我有一个使用以下Java 8 LocalDate API计算的基于ISO的周号

int weekNumOfYear = LocalDate#get(IsoFields.WEEK_OF_WEEK_BASED_YEAR)

给定年份和星期数（例如，201927），如何计算本周(201917)的开始日期和结束日期？

我正在使用Calendar类解决此问题，但不确定它是否正确（尤其是是否遵循ISO格式）

Update： The following code doesn't work correctly for 201953, there is no 53th week for 2019

@Test
    public void testGetWeekDays() {
        Integer year = 2019;
        Integer week = 27;
        SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");
        Calendar cal = Calendar.getInstance();

        //Use ISO format
        cal.setMinimalDaysInFirstWeek(4);

        cal.setFirstDayOfWeek(Calendar.MONDAY);
        cal.set(Calendar.YEAR, year);
        cal.set(Calendar.WEEK_OF_YEAR, week);
        cal.set(Calendar.DAY_OF_WEEK, cal.getFirstDayOfWeek());
        String beginDate = sdf.format(cal.getTime());
        cal.add(Calendar.DAY_OF_WEEK, 6);
        String endDate = sdf.format(cal.getTime());
        System.out.println(beginDate);
        System.out.println(endDate);
    }