java - 转换后的 java.util.Date 的 ChronoUnit.between()

Question

这有效(返回 0):

ChronoUnit.SECONDS.between(
        LocalDateTime.now(),
        LocalDateTime.now());

这失败了:

ChronoUnit.SECONDS.between(
        ZonedDateTime.ofInstant(new Date().toInstant(), ZoneId.of("UTC"),
        LocalDateTime.now());

除了这个异常(exception):

Exception in thread "main" java.time.DateTimeException: Unable to obtain ZonedDateTime from TemporalAccessor: 2016-10-27T14:05:37.617 of type java.time.LocalDateTime
...
Caused by: java.time.DateTimeException: Unable to obtain ZoneId from TemporalAccessor: 2016-10-27T14:05:37.617 of type java.time.LocalDateTime
at java.time.ZoneId.from(ZoneId.java:466)
at java.time.ZonedDateTime.from(ZonedDateTime.java:553)
... 3 more

有人知道如何在 ChronoUnit.between() 中使用 java.util.Date 吗？

Answer 1

ChronoUnit.between 的文档方法说:

This calculates the amount in terms of this unit. The start and end points are supplied as temporal objects and must be of compatible types. The implementation will convert the second type to be an instance of the first type before the calculating the amount.

它正在尝试将 LocalDateTime 转换为 ZonedDateTime。 LocalDateTime 没有区域信息并导致错误。

如果您使用 ZonedDateTime 作为第二个参数，它可以正常工作:

ChronoUnit.SECONDS.between(ZonedDateTime.ofInstant(new Date().toInstant(), ZoneId.of("UTC")), ZonedDateTime.now())