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Comment by bxparks | Hacker News Reader

I find that the Java 8 java.time API [1] easier to understand than Joda Time [2] when working with timezones. In particular, the OffsetDateTime and ZonedDateTime classes in java.time seem well-designed and easy to use. The equivalents in Joda Time are harder for me.

[1] https://docs.oracle.com/javase/8/docs/api/java/time/package-...

[2] https://www.joda.org/joda-time/apidocs/index.html

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Agreed. Joda had the right abstractions (instants, durations, etc) but the class hierarchy for them was unnecessarily complex. A lot of this complexity comes from opting for the abstractions to be either mutable or immutable.

For example, `ReadableInstant` [1] in Joda implements 3 interfaces and has 7 subclasses. And really, what is the difference between `AbstractDateTime` and `BaseDateTime`? Whereas `Instant` from java.time [2] is an immutable value type and I haven't found it lacking in any respect.

On the whole java.time has struck me as extremely well designed (after coming from Python and previous date and time libraries in Java) and I think it would behoove other languages to liberally copy its design.

[1] https://www.joda.org/joda-time/apidocs/org/joda/time/Readabl...

[2] https://docs.oracle.com/javase/8/docs/api/java/time/Instant....

Considering that JodaTime was more or less the reference for java.time, I would be very disappointed if java.time was worse and didn't get rid of JodaTime's design flaws.

> Considering that JodaTime was more or less the reference for java.time

It would probably be more correct to say that java.time is Joda version 2. Colebourne, the original author of Joda, was also one of the leads on JSR-310, and very much intended that 310 learn from the mistakes on Joda.

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