Date and time conversion to some other Timezone in java

Question

i have written this code to convert the current system date and time to some other timezone. I am not getting any error but i am not getting my output as expected. Like if i

Answer 1

2020 Answer Here

If you want the new java.time.* feature but still want to mess with java.util.Date:

 public static Date convertBetweenTwoTimeZone(Date date, String fromTimeZone, String toTimeZone) {
        ZoneId fromTimeZoneId = ZoneId.of(fromTimeZone);
        ZoneId toTimeZoneId = ZoneId.of(toTimeZone);

        ZonedDateTime fromZonedDateTime =
                ZonedDateTime.ofInstant(date.toInstant(), ZoneId.systemDefault()).withZoneSameLocal(fromTimeZoneId);

        ZonedDateTime toZonedDateTime = fromZonedDateTime
                .withZoneSameInstant(toTimeZoneId)
                .withZoneSameLocal(ZoneId.systemDefault())
                ;

        return Date.from(toZonedDateTime.toInstant());
    }

for java.sql.Timestamp

    public static Timestamp convertBetweenTwoTimeZone(Timestamp timestamp, String fromTimeZone, String toTimeZone) {

        ZoneId fromTimeZoneId = ZoneId.of(fromTimeZone);
        ZoneId toTimeZoneId = ZoneId.of(toTimeZone);

        LocalDateTime localDateTimeBeforeDST = timestamp.toLocalDateTime();

        ZonedDateTime fromZonedDateTime = ZonedDateTime.of(localDateTimeBeforeDST, fromTimeZoneId);

        ZonedDateTime toZonedDateTime = fromZonedDateTime.withZoneSameInstant(toTimeZoneId);

        return Timestamp.valueOf(toZonedDateTime.toLocalDateTime());
    }