Want to be able to create custom timezones offset from a particular zone (but observing daylight savings transitions). For example would like to be able to indicate:
ZoneId.of("America/New_York+7")
The above zone would observe either EST or EDT, depending on daylight savings time + 7 hours. The application for this relates to FX markets start / end of day (which is 5pm New York time).
The above offset format is disallowed in ZoneId, as ZoneId only allows for offsets from UTC.
I had implemented a class which generates custom ZoneRules, but then the ZoneRegion constructor, a subclass of ZoneId is not public. ZoneRegion has the following, unavailable constructor:
ZoneRegion(String name, ZoneRules rules)
So the question is, short of not using the java.time library, is there any way to get the behavior of a custom zone with DST rules? Alternatively, does someone know how this would be done using the Joda date/time library?
Addendum
Note that one cannot create subclasses of ZoneId due to the following code in ZoneId (which frankly, seems like a very bad idea unless there is some security reason which I cannot fathom):
/**
* Constructor only accessible within the package.
*/
ZoneId() {
if (getClass() != ZoneOffset.class && getClass() != ZoneRegion.class) {
throw new AssertionError("Invalid subclass");
}
}
