Converting ISO 8601-compliant String to java util Date

0 votes

I am trying to convert an ISO 8601 formatted String to a java.util.Date.

I found the pattern yyyy-MM-dd'T'HH:mm:ssZ to be ISO8601-compliant if used with a Locale (compare sample).

However, using the java.text.SimpleDateFormat, I cannot convert the correctly formatted String 2010-01-01T12:00:00+01:00. I have to convert it first to 2010-01-01T12:00:00+0100, without the colon.

So, the current solution is

SimpleDateFormat ISO8601DATEFORMAT = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ssZ", Locale.GERMANY);
String date = "2010-01-01T12:00:00+01:00".replaceAll("\\+0([0-9]){1}\\:00", "+0$100");
System.out.println(ISO8601DATEFORMAT.parse(date));
which obviously isn't that nice. Am I missing something or is there a better solution?
Nov 27, 2018 in Java by Sushmita
• 6,920 points

recategorized Nov 28, 2018 by Sushmita 9,766 views

1 answer to this question.

0 votes

Unfortunately, the time zone formats available to SimpleDateFormat (Java 6 and earlier) are not ISO 8601 compliant. SimpleDateFormat understands time zone strings like "GMT+01:00" or "+0100", the latter according to RFC # 822.

Even if Java 7 added support for time zone descriptors according to ISO 8601, SimpleDateFormat is still not able to properly parse a complete date string, as it has no support for optional parts.

Reformatting your input string using regexp is certainly one possibility, but the replacement rules are not as simple as in your question:

  • Some time zones are not full hours off UTC, so the string does not necessarily end with ":00".
  • ISO8601 allows only the number of hours to be included in the time zone, so "+01" is equivalent to "+01:00"
  • ISO8601 allows the usage of "Z" to indicate UTC instead of "+00:00".

The easier solution is possibly to use the data type converter in JAXB, since JAXB must be able to parse ISO8601 date string according to the XML Schema specification. javax.xml.bind.DatatypeConverter.parseDateTime("2010-01-01T12:00:00Z") will give you a Calendar object and you can simply use getTime() on it, if you need a Date object.

You could probably use Joda-Time as well, but I don't know why you should bother with that.

Hope it helps!

To know more about Java, It's recommended to join our Java Training in Chennai today.

answered Nov 27, 2018 by Daisy
• 8,140 points

edited Oct 7, 2021 by Sarfaraz

Related Questions In Java

0 votes
2 answers

How can we convert java.util.Date to java.sql.date in Java?

It's easy to convert a java.util.Date object ...READ MORE

answered Aug 27, 2019 in Java by Sirajul
• 59,230 points
1,331 views
+1 vote
1 answer

Converting a date string to a DateTime object using Joda Time library

Use DateTimeFormat: DateTimeFormatter formatter = DateTimeFormat.forPattern("dd/MM/yyyy HH:mm:ss"); DateTime dt = ...READ MORE

answered Jul 24, 2018 in Java by scarlett
• 1,290 points
4,882 views
0 votes
2 answers

Converting between java.time.LocalDateTime and java.util.Date

Try this: Date in = new Date(); LocalDateTime ldt ...READ MORE

answered Aug 27, 2019 in Java by Sirajul
• 59,230 points
2,891 views
0 votes
2 answers

Java string to date conversion

We can convert String to Date in java using parse() method ...READ MORE

answered Dec 29, 2020 in Java by Nikita
1,311 views
0 votes
2 answers

Date format conversion in Java

Calendar cal = Calendar.getInstance(); cal.add(Calendar.DATE, 1); Date date = ...READ MORE

answered Aug 13, 2018 in Java by Sushmita
• 6,920 points
1,073 views
0 votes
3 answers

Change date format in a Java string

The reason for the inaccuracy is because ...READ MORE

answered Feb 9, 2022 in Java by Soham
• 9,710 points
3,360 views
0 votes
1 answer

Unexpected result on Subtracting Times

ou've encountered a local time discontinuity: When local standard ...READ MORE

answered May 29, 2018 in Java by Rishabh
• 3,620 points
598 views
0 votes
1 answer

How can I get the current date and time in UTC or GMT in Java?

This definitely returns UTC time: as String ...READ MORE

answered Jun 7, 2018 in Java by Rishabh
• 3,620 points
27,613 views
0 votes
3 answers

String to Double conversion in java

Double temp = Double.valueOf(str); number = temp.doubleValue(); READ MORE

answered Sep 10, 2018 in Java by Sushmita
• 6,920 points
1,727 views
0 votes
3 answers

How to reverse a string in java?

public static String reverse(String s) { ...READ MORE

answered Aug 17, 2018 in Java by samarth295
• 2,220 points
1,570 views
webinar REGISTER FOR FREE WEBINAR X
REGISTER NOW
webinar_success Thank you for registering Join Edureka Meetup community for 100+ Free Webinars each month JOIN MEETUP GROUP