Output RFC 3339 Timestamp in Java

I spent quite a lot of time looking for an answer to the same issue and I found something here : http://developer.android.com/reference/java/text/SimpleDateFormat.html

Suggested answer:

String timestamp = new SimpleDateFormat("yyyy-MM-dd'T'h:m:ssZZZZZ").format(new Date());

If you notice I am using 5 'Z' instead of one. This gives the output with a colon in the offset like this: "2008-11-13T12:23:30-08:00". Hope it helps.

Starting in Java 7, there's the X pattern string for ISO8601 time zone. For strings in the format you describe, use XXX. See the documentation.

Sample:

System.out.println(new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ssXXX")
        .format(new Date()));

Result:

2014-03-31T14:11:29+02:00

Check out the Joda Time package. They make RFC 3339 date formatting a lot easier.

Joda Example:

DateTime dt = new DateTime(2011,1,2,12,45,0,0, DateTimeZone.UTC);
DateTimeFormatter fmt = ISODateTimeFormat.dateTime();
String outRfc = fmt.print(dt);

From the "get it done dept," one solution is to use regexes to fix up the string after SimpleDateFormat has completed. Something like s/(\d{2})(\d{2})$/$1:$2/ in Perl.

If you are even remotely interested in this, I will edit this response with the working Java code.

But, yeah. I am hitting this problem too. RFC3339, I'm looking at you!

EDIT:

This works for me

// As a private class member
private SimpleDateFormat rfc3339 = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ssZ");

String toRFC3339(Date d)
{
   return rfc3339.format(d).replaceAll("(\\d\\d)(\\d\\d)$", "$1:$2");
}