Java 8 – Create Instant from LocalDateTime with TimeZone

java date java-8 localdate
La Carbonell picture La Carbonell · Jun 15, 2017 · Viewed 56.9k times · Source

I have a date stored in the DB in string format ddMMyyyy and hh:mm and the TimeZone. I want to create an Instant based on that information, but I don't know how to do it.

something like

LocalDateTime dateTime = LocalDateTime.of(2017, Month.JUNE, 1, 13, 39);
Instant instant = dateTime.toInstant(TimeZone.getTimeZone("ECT"));

Answer

Jorn Vernee picture Jorn Vernee · Jun 15, 2017

You can first create a ZonedDateTime with that time zone, and then call toInstant:

LocalDateTime dateTime = LocalDateTime.of(2017, Month.JUNE, 15, 13, 39);
Instant instant = dateTime.atZone(ZoneId.of("Europe/Paris")).toInstant();
System.out.println(instant); // 2017-06-15T11:39:00Z

I also switched to using the full time zone name (per Basil's advice), since it is less ambiguous.

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