Time: Use `java.time` rather than Joda-Time

[rtyley]

Representing time - moments in time, durations, calendar calculations, etc - should always be done with strongly-typed classes where possible, rather than simple integer types (which are a bad choice because they don't include units - eg. 5 could represent 5 minutes, seconds, or even milliseconds).

Joda-Time recommends moving to java.time.* - and has for a long time!

Java has had an excellent built-in time-representation library in the java.time.* package since Java 8, released in 2014. Prior to that, the best available option was Joda-Time (written by the same person who went on to advise on java.time, Stephen Colebourne) - and at the Guardian we still have active production code that still uses Joda-Time - but where we're updating code, we should aim to migrate to java.time.*.

Equivalent classes in java.time

• org.joda.time.Instant → java.time.Instant
• org.joda.time.DateTime → java.time.ZonedDateTime - assuming that you need to have localised date - if not, you may want to be using java.time.Instant instead.

See https://blog.joda.org/2014/11/converting-from-joda-time-to-javatime.html for a full list.

Examples

• https://github.com/guardian/ophan/pull/3988
• https://github.com/guardian/ophan/issues/4202
• Use strongly-typed Durations for time riff-raff#1348
• https://github.com/guardian/janus/pull/4688
• Drop Scala 2.12, drop Joda-Time - maxAuthAge becomes a java.time.Duration play-googleauth#201
• Mss 339/remove joda time pa-football-client#42