Codename One Date parsing

Question

Trying to parse ISO8601 using codenameone libraries for SimpleDateFormat. I'm getting the error below;

String input = "2019-08-30T00:34:34Z";
       SimpleDateFormat format = new 
       SimpleDateFormat(DateFormatPatterns.ISO8601);
       Date date = format.parse(input);

java.lang.StringIndexOutOfBoundsException: String index out of range: -18

See https://stackoverflow.com/questions/2201925/converting-iso-8601-compliant-string-to-java-util-date — Robert, Aug 29 '19 at 22:03
FYI, the terribly troublesome date-time classes such as [`java.util.Date`](https://docs.oracle.com/javase/10/docs/api/java/util/Date.html), [`java.util.Calendar`](https://docs.oracle.com/javase/10/docs/api/java/util/Calendar.html), and `java.text.SimpleDateFormat` are now [legacy](https://en.wikipedia.org/wiki/Legacy_system), supplanted by the [*java.time*](https://docs.oracle.com/javase/10/docs/api/java/time/package-summary.html) classes built into Java 8 and later. See [*Tutorial* by Oracle](https://docs.oracle.com/javase/tutorial/datetime/TOC.html). — Basil Bourque, Aug 29 '19 at 22:30
All of the other answers here and these comments aren't applicable to Codename One which unfortunately doesn't have yet JSR310 — Shai Almog, Aug 30 '19 at 02:25

score 1 · Accepted Answer · answered Aug 30 '19 at 02:24

1

This is a bug with zulu time. I'm not exactly sure how this happened as this code has been there for ages but it should work with today's update.

answered Aug 30 '19 at 02:24

Shai Almog

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score -1 · Answer 2 · answered Aug 29 '19 at 22:20

Looking at the source code of DateFormatPatterns, ISO8601 is defined as "yyyy-MM-dd'T'HH:mm:ssZ".

Putting that into a minimal plain old Java example:

import java.util.Date;
import java.text.*;

public class DateProblem {
    public static void main(String[] args) throws Exception {
        String input = "2019-08-30T00:34:34Z";
        SimpleDateFormat format = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ssZ");
            // DateFormatPatterns.ISO8601
        Date date = format.parse(input);     
        System.out.println(date);
   }
}

gets me an "unparsable date" error (but not the string index error you got).

Checking the Javadoc for SimpleDateFormat shows that Z stands for RFC 822 format, that is a+ or - and 4 digits (offset in hours and minutes from GMT). Change the Z in your input to such a time zone offset, for example like this:

String input = "2019-08-30T00:34:34-0600";

This parses fine for me.

That said, the whole SimpleDateFormat et al are deprecated. You should switch to the new java.time API

Codename One Date parsing

2 Answers2