How can I parse a date including timezone with Joda Time

Question

This snippet of code always parses the date into the current timezone, and not into the timezone in the string being parsed.

final DateTimeFormatter df = DateTimeFormat
        .forPattern("EEE MMM dd HH:mm:ss 'GMT'Z yyyy");
final DateTime dateTime = df
        .parseDateTime("Mon Aug 24 12:36:46 GMT+1000 2009");
System.out.println("dateTime = " + dateTime);
// outputs dateTime = 2009-08-24T04:36:46.000+02:00

It outputs:

dateTime = 2009-08-24T04:36:46.000+02:00

whereas I expect:

dateTime = 2009-08-24T04:36:46.000+10:00

Any ideas what I'm doing wrong?

score 78 · Accepted Answer · edited Nov 15 '12 at 09:20

78

OK, further Googling gave me the answer to my own question: use withOffsetParsed(), as so:

final DateTimeFormatter df = DateTimeFormat
        .forPattern("EEE MMM dd HH:mm:ss 'GMT'Z yyyy");
final DateTime dateTime = df.withOffsetParsed()
        .parseDateTime("Mon Aug 24 12:36:46 GMT+1000 2009");

This works.

edited Nov 15 '12 at 09:20

Björn Pollex

75,346
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answered Aug 25 '09 at 10:19

Steve McLeod

51,737
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8

IMO, the default behavior of `DateTimeFormatter` seems to violate "principle of least astonishment", especially in the context of an unmarshaller. Thank you Steve for unearthing `withOffsetParsed()`. – David J. Liszewski May 20 '15 at 02:46
I have to agree that the default behaviour - i.e. ignoring a properly parsed timezone - is bizarre. – Clyde Nov 22 '17 at 05:45

score 37 · Answer 2 · answered May 04 '13 at 02:25

37

also you can chose:

// parse using the Paris zone
DateTime date = formatter.withZone(DateTimeZone.forID("Europe/Paris")).parseDateTime(str);

answered May 04 '13 at 02:25

z0mb1ek

899
9
16

score 1 · Answer 3 · answered Jul 11 '21 at 09:09

java.time

Quoted below is a notice from the home page of Joda-Time:

Note that from Java SE 8 onwards, users are asked to migrate to java.time (JSR-310) - a core part of the JDK which replaces this project.

Do not use a fixed text for the timezone:

Do not use a fixed text (e.g. 'GMT') for the timezone as you have done because that approach may fail for other locales.

Solution using java.time, the modern Date-Time API:

import java.time.OffsetDateTime;
import java.time.format.DateTimeFormatter;
import java.util.Locale;

public class Main {
    public static void main(String[] args) {
        String strDateTime = "Mon Aug 24 12:36:46 GMT+1000 2009";
        DateTimeFormatter parser = DateTimeFormatter.ofPattern("E MMM d H:m:s VVZ u", Locale.ENGLISH);
        OffsetDateTime odt = OffsetDateTime.parse(strDateTime, parser);
        System.out.println(odt);

        // Custom fromat
        DateTimeFormatter formatter = DateTimeFormatter.ofPattern("uuuu-MM-dd'T'HH:mm:ss.SSSXXX", Locale.ENGLISH);
        System.out.println(formatter.format(odt));
    }
}

Output:

2009-08-24T12:36:46+10:00
2009-08-24T12:36:46.000+10:00

ONLINE DEMO

Learn more about the modern Date-Time API from Trail: Date Time.

^{* For any reason, if you have to stick to Java 6 or Java 7, you can use ThreeTen-Backport which backports most of the java.time functionality to Java 6 & 7. If you are working for an Android project and your Android API level is still not compliant with Java-8, check Java 8+ APIs available through desugaring and How to use ThreeTenABP in Android Project.}

I prefer `'GMT'Z`. `GMT+1000` are not two pieces of information, `GMT` and `+1000` (which would have contradicted each other), but one piece. When we cannot parse as one piece, I prefer only to parse the bit that holds relevant information, that is `+1000`. If one day (however unlikely) someone parsed into a `ZonedDateTime` using your formatter, they would get a result that was 10 hours off. Your `VV` will tell the reader that `GMT` is the zone ID of the date and time, which is not the case, so it will confuse rather than help. — Ole V.V., Jul 11 '21 at 09:25
@OleV.V. - "If one day (however unlikely) someone parsed into a ZonedDateTime using your formatter, they would get a result that was 10 hours off." - This is not correct. `System.out.println(ZonedDateTime.parse(strDateTime, parser))` gives `2009-08-24T02:36:46Z[GMT]` which represents the same instant/moment in time i.e. `2009-08-24T12:36:46+10:00` = `2009-08-24T02:36:46Z[GMT]`. — Arvind Kumar Avinash, Jul 11 '21 at 09:34
Your code holds even more surprises than I had thought. While you get the correct instant, you don’t get the expected time of day nor the expected zone. (And on Java 8 I got `2009-08-24T12:36:46Z[GMT]`, may be a bug in Java 8.) — Ole V.V., Jul 11 '21 at 09:43
It must be a bug in Java 8. Ideone server currently uses Java-12 and [here](https://ideone.com/CKAvgA) are the results on it. — Arvind Kumar Avinash, Jul 11 '21 at 09:53

How can I parse a date including timezone with Joda Time

3 Answers3

java.time

Do not use a fixed text for the timezone:

Linked

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