java8 utc时间转换,如何使用Java 8库将UTC日期时间转换为另一个时区？

final Timestamp rawDateTime = Timestamp.valueOf("2031-04-25 18:30:00");

final ZoneId zoneId = ZoneId.of("Asia/Calcutta");

final ZonedDateTime zonedDateTime = ZonedDateTime.ofInstant(

Instant.ofEpochMilli(rawDateTime.getTime()), zoneId);

// here we are getting output as 2031-04-25T18:30+05:30[Asia/Calcutta]

final ZonedDateTime zonedDateTime1 =

ZonedDateTime.of(rawDateTime.toLocalDateTime(), zoneId);

// here we are getting output as 2031-04-25T18:30+05:30[Asia/Calcutta]

But I want to get the converted date time as 2031-04-26 00:00:00+5:30 as my timestamp value is in the UTC Timezone.

Please help.

解决方案

First, you should not use Timestamp. You can use DateTimeFormatter to parse into a LocalDateTime.

You then zone that LocalDateTime to UTC before converting to the Calcutta zone with ZonedDateTime.withZoneSameInstant.

DateTimeFormatter formatter = new DateTimeFormatterBuilder()

.append(DateTimeFormatter.ISO_LOCAL_DATE)

.appendLiteral(' ')

.append(DateTimeFormatter.ISO_LOCAL_TIME)

.toFormatter();

LocalDateTime localDateTime = LocalDateTime.parse("2031-04-25 18:30:00", formatter);

ZoneId calcuttaZone = ZoneId.of("Asia/Calcutta");

ZonedDateTime calcuttaZonedDateTime = localDateTime.atZone(ZoneOffset.UTC)

.withZoneSameInstant(calcuttaZone);