java8 根據年份和周數 獲取周一和周日日期

WeekFields weekFields= WeekFields.ISO;
LocalDate now = LocalDate.now();
//輸入你想要的年份和周數
LocalDate localDate = now.withYear(2021).with(weekFields.weekOfYear(),1);

//以周一為每周的第一天

//周一（第一天）
LocalDate localDate1 = localDate.with(weekFields.dayOfWeek(), 1L);
//周日（第七天）
LocalDate localDate7 = localDate.with(weekFields.dayOfWeek(), 7L);

//以周日為每周的第一天

//周日（第一天）
LocalDate localDate1 = localDate.with(WeekFields.of(Locale.US).dayOfWeek(), 1L);

//周六（第七天）
LocalDate localDate7 = localDate.with(weekFields.dayOfWeek(), 6L);