How to retrieve the date format for a locale

I've been using DateFormat to format dates, but now I need to pass the format for the locale to the jQuery Date widget. How can I get the format?

Update:

To clarify, I need to get the pattern in Java开发者_C百科 so I can output it elsewhere. e.g. in some JavaScript where I might want to create a string like this with the date format in it:

$('#datepicker').datepicker({'dateFormat':'dd/mm/yy'})

You can get the date pattern by using

((SimpleDateFormat) DateFormat.getDateTimeInstance(DateFormat.LONG, DateFormat.LONG, Locale.UK)).toPattern()

or if you just need the date

((SimpleDateFormat) DateFormat.getDateInstance(DateFormat.SHORT, Locale.UK)).toPattern()

API: SimpleDateFormat.toPattern(), DateFormat.getDateTimeInstance(), DateFormat.getDateInstance()

Second question is how to convert that to jQuery specific format pattern.

Java date formatting. vs jQuery DatePicker Date Formatting

• day of year in java D, in jQuery o
• short year in Java yy, in jQuery y
• long year in Java yyyy, in jQuery yy
• Month without leading zeros in Java M, in jQuery m
• Month with leading zeros in Java MM, in jQuery mm
• Month name short in Java MMM, in jQuery M
• Month name long in Java MMMM in jQuery MM -

I have been looking at this recently and haven't found an easy way to find this out using the standard library. I require this to localise the Wicket class org.apache.wicket.extensions.markup.html.form.DateTextField, which takes a SimpleDateFormat pattern rather than a DateFormat object. Here is the code I finally decided to use, it doesn't rely on the implementation details of the JVM but has to parse the output of the DateFormat.format for a particular date (11/22/3333 - in US format).

public static String simpleDateFormatForLocale(Locale locale) {
    TimeZone commonTimeZone = TimeZone.getTimeZone("UTC");
    Calendar c = Calendar.getInstance(commonTimeZone);
    c.set(3333, Calendar.NOVEMBER, 22);

    DateFormat localeDateFormat = DateFormat.getDateInstance(DateFormat.SHORT, locale);
    localeDateFormat.setTimeZone(commonTimeZone);
    String dateText = localeDateFormat.format(c.getTime());

    return dateText.replace("11", "MM").replace("22", "dd").replace("3333", "yyyy").replace("33", "yyyy");
}

In my case I want to force the use of yyyy even if the format returns a two digit year. That is why I call replace for the year twice.

Here is the output for some sample locales:

en_US  11/22/33  MM/dd/yyyy
en_CA  22/11/33  dd/MM/yyyy
zh_CN  33-11-22  yyyy-MM-dd
de     22.11.33  dd.MM.yyyy
ja_JP  33/11/22  yyyy/MM/dd

If anyone can improve on this I would love to see their solution.