Java Reference
In-Depth Information
// Create some zoned datetimes
ZoneId usCentralZone = ZoneId.of("America/Chicago");
ZonedDateTime zdt2 = ZonedDateTime.of(ldt, usCentralZone);
System.out.println(zdt2);
// Get zone offset and zone id
ZoneOffset offset = zdt2.getOffset();
ZoneId zone = zdt2.getZone();
System.out.println("Offset:" + offset + ", Zone:" + zone);
// Subtract 10 hours. Zone-offset changes from -05:00 to -06:00
ZonedDateTime zdt3 = zdt2.minusHours(10);
System.out.println(zdt3);
// Create a datetime in Asia/Kolkata time zone
ZoneId indiaKolkataZone = ZoneId.of("Asia/Kolkata");
ZonedDateTime zdt4 = ZonedDateTime.of(ldt, indiaKolkataZone);
System.out.println(zdt4);
// Perform some conversions on zoned date time
LocalDateTime ldt2 = zdt4.toLocalDateTime();
OffsetDateTime odt = zdt4.toOffsetDateTime();
Instant i1 = zdt4.toInstant();
System.out.println("To local datetime: " + ldt2);
System.out.println("To offset datetime: " + odt);
System.out.println("To instant: " + i1);
}
}
Current zoned datetime:2014-01-07T21:20:58.200-06:00[America/Chicago]
2012-03-11T07:30-05:00[America/Chicago]
Offset:-05:00, Zone:America/Chicago
2012-03-10T20:30-06:00[America/Chicago]
2012-03-11T07:30+05:30[Asia/Kolkata]
To local datetime: 2012-03-11T07:30
To offset datetime: 2012-03-11T07:30+05:30
To instant: 2012-03-11T02:00:00Z
Same Instant, Different Times
Sometimes you want to convert a datetime in a time zone to a datetime in another time zone. It is similar to asking
the date and time in India when it is May 14, 2012 16:30 in Chicago. You can get this in several ways. You can use
the
toInstant()
method of the
ZonedDateTime
class to get the instant from the first zoned datetime and use the
ofInstant()
method to create the second zoned datetime. You can also use the
withZoneSameInstant(ZoneId
newZoneId)
method of the
ZonedDateTime
class, as shown in Listing 12-10, to achieve the same result.
