Format XMLGregorianCalendar in java

Question

i have a date String which looks just like this.

2017-12-06T17:39:00Z

What i would like to do is to convert this String to XMLGregorianCalendar but using the same format.

What i do at the moment is:

String choosenDate = 2017-12-06T17:39:00Z;

GregorianCalendar c = new GregorianCalendar();

DateTimeFormatter timeFormatter = DateTimeFormatter.ISO_DATE_TIME;
TemporalAccessor accessor = timeFormatter.parse(dateChoisie);

Date date = Date.from(Instant.from(accessor));
c.setTime(date);
System.err.println("choosenDate: " + dateChoisie);
System.err.println("date : " + date);
XMLGregorianCalendar dateXMLGreg = null;
try
{
    dateXMLGreg = DatatypeFactory.newInstance().newXMLGregorianCalendar(c);
    System.err.println("dateXMLGreg: " + dateXMLGreg);
}
catch (DatatypeConfigurationException e)
{
    messages.addMessage(new MessageBuilder().error().code("webservice.failure").build());
}

which gives me the following output:

10:47:45,957 ERROR [stderr] (default task-47) choosenDate: 2017-12-06T17:39:03Z

10:47:45,957 ERROR [stderr] (default task-47) date : Wed Dec 06 18:39:03 CET 2017

10:47:45,958 ERROR [stderr] (default task-47) dateXMLGreg: 2017-12-06T18:39:03.000+01:00

So how can i do so i have my XMLGregorianCalendar dateXMLGreg to look like:

2017-12-06T17:39:03Z

Answer 1

This is easier than you think.

    String isoDateTime = "2017-12-06T17:39:00Z";
    XMLGregorianCalendar dateXMLGreg = DatatypeFactory.newInstance()
            .newXMLGregorianCalendar(isoDateTime);
    System.out.println(dateXMLGreg);

This prints

2017-12-06T17:39:00Z

newXMLGregorianCalendar has an overloaded version that accepts a string — your string — as argument. I trust you to add try/catch as in your question.

Edit: your XMLGregorianCalendar will have its milliseconds set to DatatypeConstants.FIELD_UNDEFINED. This needs to be so to avoid printing the milliseconds as part of the result from toString() (which gets implicitly called when you print the XMLGregorianCalendar).

One more edit: As Basil Bourque correctly said in a comment, depending on what you need your XMLGregorianCalendar for, you may use and even benefit from using a class from java.time, the modern Java date and time API, instead. For example:

    Instant dateInst = Instant.parse(isoDateTime);
    System.out.println(dateInst);

This gives the exact same output as above, 2017-12-06T17:39:00Z. The Instant class will work only if the offset is always Z, which it probably is since this was what you asked to have back. The potential advantages of java.time include (1) the API is generally much nicer to work with (2) in case you need some further date-time operations, the modern API offers a wealth of them. If the offset may vary, you may experiment with OffsetDateTime, but this is a longer story that I will leave for some other question.

Answer 2

like this.

    private XMLGregorianCalendar change(String dateStr) {
    XMLGregorianCalendar xmlDate = null;

    try {
        DateFormat format = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss'Z'");
        Date date = format.parse(dateStr);

        GregorianCalendar calendar = new GregorianCalendar();
        calendar.setTime(date);

        xmlDate = DatatypeFactory.newInstance().newXMLGregorianCalendar(calendar);
        System.out.println(xmlDate.toString());
    } catch (Exception e) {
        e.printStackTrace();
    }

    return xmlDate;
}