How do I make java.sql.Timestamp UTC time? [duplicate]

Answer 1

You might need to use the specific overload of setTimestamp that takes a Calendar object if you want to represent a "TIMESTAMP WITH TIME ZONE" value.

Answer 2

You are best to get a Timestamp from a LocalDateTime, rather than from an Instant.

The first step is to take your ZonedDateTime and convert it to GMT:

ZonedDateTime gmt = zdt.withZoneSameInstant(ZoneId.of("GMT"));

Then you can convert it to a Timestamp via a LocalDateTime:

Timestamp timestamp = Timestamp.valueOf(gmt.toLocalDateTime());