How can I get operating system Time zone in Java?

Question

The TimeZone.getDefault() returns the System Time zone until it's changed.

Sample 1:

System.out.println(TimeZone.getDefault());

Result:

Europe/Kaliningrad

It is system time zone.

Sample 2:

TimeZone.setDefault(TimeZone.getTimeZone("Asia/Kolkata"));
System.out.println(TimeZone.getDefault());

Result:

Asia/Kolkata

It isn't system time zone, system time zone is still Europe/Kaliningrad.

So how can I get system time zone even after change default DateTimeZone.

the answer in previous post https://stackoverflow.com/questions/24806183/get-date-in-current-timezone-in-java — Ori Marko, Jun 14 '17 at 12:00
@user7294900, it returns Asia/Calcutta instead Europe/Kaliningrad — Evgenia, Jun 14 '17 at 12:07
What are you expecting? When you call `setDefault`, it changes the default timezone for the whole JVM, **that's the expected behaviour**. If you don't want to change it, then don't call `setDefault` (or save the timezone in a variable before changing the default, as already suggested in the answers below). — , Jun 14 '17 at 12:21
@Hugo, I want to get System Time Zone (which is set for the operating system) regardless of which time zone is set on JVM. — Evgenia, Jun 14 '17 at 12:29
Maybe this can help: https://docs.oracle.com/javase/8/docs/technotes/guides/troubleshoot/time-zone.html — , Jun 14 '17 at 12:32

score 3 · Answer 1 · answered Jun 14 '17 at 11:52

3

You can check system property user.timezone:

   System.getProperty("user.timezone")

answered Jun 14 '17 at 11:52

Evgeniy Dorofeev

score 0 · Answer 2 · answered Jun 14 '17 at 11:47

0

Store the value of TimeZone.getDefault() in a variable before following codes

TimeZone.setDefault(TimeZone.getTimeZone("Asia/Kolkata"));
System.out.println(TimeZone.getDefault());

and use the variable later.

answered Jun 14 '17 at 11:47

Bishwash

1

I hope that there is more beautiful solution. – Evgenia Jun 14 '17 at 11:53
@Evgenia TimeZone.setDefault overrides the system timezone so storing system timezone in a variable seems the good alternative. – Bishwash Jun 14 '17 at 12:35

2 Answers2