DateTime dt = new DateTime("2014-09-15T21:20:14");
System.out.println(dt);
System.out.println(dt.plusMillis(581042272).toDateTime().toLocalDateTime().toDateTime(DateTimeZone.forID("GMT")));
the time in dt is in UTC, I want to set the time in dt plus milliseconds to GMT? However, the time is still printed as UTC (1 hour behind GMT). How can I set it so it's one hour in front?
2014-09-15T21:20:14.000+01:00
2014-09-22T14:44:16.272Z
I know the time is exactly one hour behind because I made this request at 15:44:16 GMT
Your DateTime
is actually not in UTC - it's in the system default time zone. To fix it, you just need to tell it that the value you're passing in is in UTC:
DateTime dt = new DateTime("2014-09-15T21:20:14", DateTimeZone.UTC);
System.out.println(dt);
DateTime other = dt.plusMillis(581042272);
System.out.println(other);
Output:
2014-09-15T21:20:14.000Z
2014-09-22T14:44:16.272Z
Also note that you can't have made the request at 15:44:16 GMT, as that hasn't occurred yet. At the time I'm writing this, it's 16:05 British Summer Time, therefore 15:05 GMT. It's important to understand that the time zone in the UK isn't "GMT" - that's just the part of the time zone when we're not observing daylight savings.
If you want to convert to the UK time zone, you want:
DateTime other = dt.plusMillis(581042272)
.withZone(DateTimeZone.forID("Europe/London"));
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