How to create a Date object, using UTC, at a specific time in the past?

Question

Is it possible to create a java.util.Date object that is guaranteed to be UTC and at a specific time in the past, like an hour ago or a day ago, and is this a g

Answer 1

You can achieve this using the java.time package, as follows:

LocalDateTime localDateTime = LocalDateTime.now(ZoneOffset.UTC).minusHours(4);
Date date = Date.from(localDateTime.atZone(ZoneOffset.UTC).toInstant());

Gives the following output:

2018-01-31T14:58:28.908
Wed Jan 31 20:28:28 IST 2018     //20:28:28 IST is 14:58:28 UTC

Which is correctly 4+5:30 hours behind my current time - Asia/Kolkata ZoneId.