Re: capturing timezone when parsing java.util.Date

From:
Lew <noone@lewscanon.com>
Newsgroups:
comp.lang.java.programmer
Date:
Fri, 26 Jun 2009 20:08:07 -0400
Message-ID:
<h23nt9$74h$1@news.albasani.net>
Robert Dodier wrote:

Hello,


Once was enough to post your query.

When a string like "2009-06-26 14:13:00-0400" is parsed to
a java.util.Date via java.text.SimpleDateFormat, the timezone
in the string is lost --- the timezone of the result isn't UTC-04:00,
instead it's the default timezone (or date formatter's timezone,
if it was assigned a non-default value).

I could pull off the trailing timezone from the string and parse
it separately and adjust the timezone of the date by hand,
but I can't see a way to do that. java.util.Date doesn't have a
method to change the timezone. java.util.Calendar has
setTimeZone, but the following:

 java.util.Date d0 = <whatever>;


Don't forget the 'import' feature.

 java.util.Calendar c = java.util.Calendar.getInstance ();
 c.setTime (d0);
 c.setTimeZone (<whatever>);
 d1 = c.getTime ();

yields a date which has the default timezone.
I can't see another way to do it with Calendar.

Any advice about how to capture the timezone when parsing
a date would be appreciated. Also, if someone wants to
recommend a different time/date library, I would be interested.
Java's built-in time/date functions are a colossal disaster,
but I digress.


Date objects don't contain timezone information.

 From <http://java.sun.com/javase/6/docs/api/java/util/Date.html>:

the Date class is intended to reflect coordinated universal time (UTC)


Use a combination of java.util.Calendar and java.text.DateFormat.

--
Lew

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