Catering for multiple date formats when converting date formats using Joda time

Question

Below code converts a date format from "yyyy-MM-dd'T'HH:mm:ss" to "MM/dd/yyyy" .

import org.joda.time.DateTime;
import org.joda.time.format.DateTimeFormat;
import org.joda.time.format.DateTimeFormatter;

public class TestDate {

    public static void main(String[] args) {

        DateTimeFormatter parser = DateTimeFormat.forPattern("yyyy-MM-dd'T'HH:mm:ss");
        DateTime dateTime = parser.parseDateTime("2014-05-19T23:59:59");
        DateTimeFormatter formatter = DateTimeFormat.forPattern("MM/dd/yyyy");
        System.out.println(formatter.print(dateTime)+"\n");

        dateTime = parser.parseDateTime("2014-06-09T03:00:23.67");
        formatter = DateTimeFormat.forPattern("MM/dd/yyyy");
        System.out.println(formatter.print(dateTime));

    }

An exception is thrown for "2014-06-09T03:00:23.67" :

Exception in thread "main" java.lang.IllegalArgumentException: Invalid format: "2014-06-09T03:00:23.67" is malformed at ".67"
    at org.joda.time.format.DateTimeFormatter.parseDateTime(DateTimeFormatter.java:899)
    at TestDate.main(TestDate.java:16)

I need to be able to cater for other possibilities also such as :

2014-05-27T03:00:32.613

I just require the "MM/dd/yyyy" part of the date, everything subsequent to that can be ignored. Do I need to anticipate every date format explained at Using Joda Date & Time API to parse multiple formats

Or can a wildcard be used which ignores everything after a certain pattern. Something like :

DateTimeFormatter parser = DateTimeFormat.forPattern("yyyy-MM-dd%");

Or I could parse the string and split at the 'T' section of the date time, just using the value that appears before 'T', though this seems unclean....

Or is there an alternative method ?

Update :

Since time is not required, instead of using :

String strDate = "2014-05-19T23:59:59";
DateTime dateTime = parser.parseDateTime(strDate);

will use :

String strDate = "2014-05-19T23:59:59";
DateTime dateTime = parser.parseDateTime(strDate.substring(0, 10));

Which will just parse 2014-05-19 part of String, this will cater for multiple time formats.

Have you checked out the Joda [ISODateTimeFormat](http://joda-time.sourceforge.net/apidocs/org/joda/time/format/ISODateTimeFormat.html)? — OldCurmudgeon, Nov 21 '14 at 16:50
@OldCurmudgeon ISODateTimeFormat does not accept multiple date formats or allow to format dates based on multiple formats ? — blue-sky, Nov 21 '14 at 16:56
Possible duplicate... http://stackoverflow.com/questions/4153602/how-to-force-joda-time-to-parse-only-part-of-string — jalopaba, Nov 21 '14 at 22:40
@jalopaba thanks. "@krtek: well, a substring(0, 10) would match 2009-05-15 in all of cases you mentioned ;-)" is written in one of the comments of your linked question - same as solution I'm using — blue-sky, Nov 22 '14 at 00:38

score 0 · Accepted Answer · answered Nov 25 '14 at 08:13

You can extract date from date-time (format yyyy-MM-dd%) string in next ways:

1) Using String::split

  String dateTime = "2014-05-19T23:59:59";
  String date = dateTime.split("T")[0];

2) Using regexp

  Pattern pattern = Pattern.compile("\\d{4}-\\d{2}-\\d{2}");
  Matcher matcher = pattern.matcher(dateTime);
  if (matcher.find())
  {
     System.out.println(matcher.group());
  }

Also you can change format yyyy-MM-dd% to MM/dd/yyyy with regexp:

  String dateTime = "2014-05-19T23:59:59"; 
  // pattern for 'yyyy-MM-dd%'
  Pattern pattern = Pattern.compile("(\\d{4})-(\\d{2})-(\\d{2}).+");
  Matcher matcher = pattern.matcher(dateTime);
  if (matcher.matches())
  {
     // date in format 'MM/dd/yyyy'
     String dateInNewFormat = String.format("%s/%s/%s", 
        matcher.group(2), matcher.group(3), matcher.group(1));
  }

Catering for multiple date formats when converting date formats using Joda time

1 Answers1