instant.truncatedTo(ChronoUnit.HOURS) returns 值大于原始值

Question

根据Instant.truncatedTo的javadoc，它的作用是

Truncating the instant returns a copy of the original with fields smaller than the specified unit set to zero.

因此，如果我用 ChronoUnit.HOURS 调用它，我希望小时不会被修改。当我用 1970 年之后的日期调用它时，这也是我所看到的。但是，在此之前它实际上返回的值大于原始值。这是预期的行为还是我遗漏了什么？

    Instant.ofEpochMilli(-1);                                          //1969-12-31T23:59:59.999Z
    Instant.ofEpochMilli(-1).truncatedTo(ChronoUnit.HOURS);            //1970-01-01T00:00:00Z
    Instant.ofEpochMilli(1);                                           //1970-01-01T00:00:00.001Z
    Instant.ofEpochMilli(1).truncatedTo(ChronoUnit.HOURS);             //1970-01-01T00:00:00Z
    Instant.ofEpochMilli(2*60*60*1000).truncatedTo(ChronoUnit.HOURS);  //1970-01-01T02:00:00Z
    Instant.ofEpochMilli(2*60*60*1000-1);                              //1970-01-01T01:59:59.999Z
    Instant.ofEpochMilli(2*60*60*1000-1).truncatedTo(ChronoUnit.HOURS);//1970-01-01T01:00:00Z

Answer 1

Is this the intended behavior

不，a bug 已在 Java 9.

中修复

instant.truncatedTo(ChronoUnit.HOURS) returns 值大于原始值

instant.truncatedTo(ChronoUnit.HOURS) returns value that is greater than original for

java

java-time