Java 8 LocalDate-如何获取两个日期之间的所有日期？

Z时代
2024-01-10
分类：问答

在新API中是否有可能获取 java.time？

假设我有这部分代码：

@Test
public void testGenerateChartCalendarData() {
    LocalDate startDate = LocalDate.now();
    LocalDate endDate = startDate.plusMonths(1);
    endDate = endDate.withDayOfMonth(endDate.lengthOfMonth());
}

现在我需要介于startDate和之间的所有日期endDate。

我正在考虑获取daysBetween两个日期中的一个并进行迭代：

long daysBetween = ChronoUnit.DAYS.between(startDate, endDate);
for(int i = 0; i <= daysBetween; i++){
    startDate.plusDays(i); //...do the stuff with the new date...
}

有没有更好的方法来获取日期？

回答：

假设您主要想在日期范围内进行迭代，那么创建一个DateRange可迭代的类将很有意义。那可以让你写：

for (LocalDate d : DateRange.between(startDate, endDate)) ...

就像是：

public class DateRange implements Iterable<LocalDate> {
  private final LocalDate startDate;
  private final LocalDate endDate;
  public DateRange(LocalDate startDate, LocalDate endDate) {
    //check that range is valid (null, start < end)
    this.startDate = startDate;
    this.endDate = endDate;
  }
  @Override
  public Iterator<LocalDate> iterator() {
    return stream().iterator();
  }
  public Stream<LocalDate> stream() {
    return Stream.iterate(startDate, d -> d.plusDays(1))
                 .limit(ChronoUnit.DAYS.between(startDate, endDate) + 1);
  }
  public List<LocalDate> toList() { //could also be built from the stream() method
    List<LocalDate> dates = new ArrayList<> ();
    for (LocalDate d = startDate; !d.isAfter(endDate); d = d.plusDays(1)) {
      dates.add(d);
    }
    return dates;
  }
}