Question

Is it possible to retrieve a default pattern for a given locale, without casting an object returned by DateFormat.get*Instance() to a SimpleDateFormat?

I understand, that in most cases everything will be OK, but there is a note in javadoc, here: “If you want even more control over the format or parsing, (or want to give your users more control), you can try casting the DateFormat you get from the factory methods to a SimpleDateFormat. This will work for the majority of countries; just remember to put it in a try block in case you encounter an unusual one.”

So I wonder, what should I do in case I “encounter an unusual one“?

Related theme.

Code sample:

/**
 * Returns '\n'-separated string with available patterns.
 * Optional adds appropriate language code to each pattern string.
 * 
 * @param showLanguage Defines if language info is required.
 * @return  String with available patterns, optional (if showLanguage is set
 * to "true") adds appropriate language code to each pattern.
 */
public String getPatternsForAvailableLocales(Boolean... showLanguage) {

    /* Array of available locales */
    Locale[] locales = DateFormat.getAvailableLocales();

    String result = "";

    for (Locale locale : locales) {

        /* Add language info, if necessary */
        if ((showLanguage.length > 0) && (showLanguage[0])) {
            result += locale.getLanguage() + '\t';
        }

        /* Retrieving pattern */ 
        try {
            result += ((SimpleDateFormat)
                    DateFormat.getDateTimeInstance(DateFormat.SHORT,
                            DateFormat.SHORT, locale)).toPattern();
        } catch (ClassCastException e) {
            // ******************************** //
            // What's up? Is there another way? //
            // ******************************** //
        }

        result += '\n';

    }
    return result;
}

Answer 1

You can retrieve the date format symbols for a particular language by executing the following Java code:

System.out.println(DateFormatSymbols.getInstance
        (new Locale("en_US")).getLocalPatternChars());
System.out.println(DateFormatSymbols.getInstance
        (new Locale("nl_NL")).getLocalPatternChars());

In this particular case, Dutch, the date format symbols are the same.

GyMdkHmsSEDFwWahKzZ
GyMdkHmsSEDFwWahKzZ

In the event that the symbols for the foreign language are different, you substitute the foreign language character for the English character in the simple format string.

The DateFormatSymbols class has existed since at least Java 1.4.2.