Display DateTime with additional zoneOffset value if Zone is present

Question

While displaying the datetime in specific format is it possible to add the offset value to the hour and date

Example: Let Say Date Time is 5/12/2023 23:18 PM is stored without any timezone in DB. Is it possible to display in particular format (consider PST) as 5/12/2023 10:18 AM

tried below methods

DateTimeFormatter COMMENT_DATE_TIME_FORMATTER_ZONE = DateTimeFormatter.ofPattern("M/d/y hh:mm a zzz");
ZonedDateTime zdt = ZonedDateTime.of(date, ZoneId.of("America/Los_Angeles"));
String zonfs = zdt.format(Constants.COMMENT_DATE_TIME_FORMATTER_ZONE); //5/12/2023 06:50 PM PDT

DateTimeFormatter COMMENT_DATE_TIME_FORMATTER = DateTimeFormatter.ofPattern("M/d/y hh:mm a"); //5/12/2023 06:50 PM


SimpleDateFormat sdf = new SimpleDateFormat("M/d/y hh:mm a");
String sdfd =sdf.format(GregorianCalendar.from(zdt).getTime()); //5/13/2023 07:20 AM  here its increasing the day by 1

Answer 1

Yes, it is possible, try this way:

LocalDateTime dateTime = LocalDateTime.of(2023, 5, 12, 23, 18);

Instant instant = dateTime.toInstant(ZoneOffset.UTC);
ZoneId pstZone = ZoneId.of("America/Los_Angeles");
ZonedDateTime pstDateTime = instant.atZone(pstZone);

DateTimeFormatter formatter = DateTimeFormatter.ofPattern("M/d/y hh:mm a");
String formattedDateTime = pstDateTime.format(formatter);