locale.java

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        this(language, "", "");
    }


    /**
     * Gets the current value of the default locale for this instance
     * of the Java Virtual Machine.
     * <p>
     * The Java Virtual Machine sets the default locale during startup
     * based on the host environment. It is used by many locale-sensitive
     * methods if no locale is explicitly specified.
     * It can be changed using the
     * {@link #setDefault(java.util.Locale) setDefault} method.
     *
     * @return the default locale for this instance of the Java Virtual Machine
     */
    public static Locale getDefault() {
        // do not synchronize this method - see 4071298
        // it's OK if more than one default locale happens to be created
        if (defaultLocale == null) {
            String language, region, country, variant;
            language = (String) AccessController.doPrivileged(
                            new GetPropertyAction("user.language", "en"));
            // for compatibility, check for old user.region property
            region = (String) AccessController.doPrivileged(
                            new GetPropertyAction("user.region"));
            if (region != null) {
                // region can be of form country, country_variant, or _variant
                int i = region.indexOf('_');
                if (i >= 0) {
                    country = region.substring(0, i);
                    variant = region.substring(i + 1);
                } else {
                    country = region;
                    variant = "";
                }
            } else {
                country = (String) AccessController.doPrivileged(
                                new GetPropertyAction("user.country", ""));
                variant = (String) AccessController.doPrivileged(
                                new GetPropertyAction("user.variant", ""));
            }
            defaultLocale = new Locale(language, country, variant);
        }
        return defaultLocale;
    }

    /**
     * Sets the default locale for this instance of the Java Virtual Machine.
     * This does not affect the host locale.
     * <p>
     * If there is a security manager, its <code>checkPermission</code>
     * method is called with a <code>PropertyPermission("user.language", "write")</code>
     * permission before the default locale is changed.
     * <p>
     * The Java Virtual Machine sets the default locale during startup
     * based on the host environment. It is used by many locale-sensitive
     * methods if no locale is explicitly specified.
     * <p>
     * Since changing the default locale may affect many different areas
     * of functionality, this method should only be used if the caller
     * is prepared to reinitialize locale-sensitive code running
     * within the same Java Virtual Machine, such as the user interface.
     *
     * @throws SecurityException
     *        if a security manager exists and its
     *        <code>checkPermission</code> method doesn't allow the operation.
     * @throws NullPointerException if <code>newLocale</code> is null
     * @param newLocale the new default locale
     * @see SecurityManager#checkPermission
     * @see java.util.PropertyPermission
     */
    public static synchronized void setDefault(Locale newLocale) {
        if (newLocale == null)
            throw new NullPointerException("Can't set default locale to NULL");

        SecurityManager sm = System.getSecurityManager();
        if (sm != null) sm.checkPermission(new PropertyPermission
                        ("user.language", "write"));
            defaultLocale = newLocale;
    }

    /**
     * Returns a list of all installed locales.
     */
    public static Locale[] getAvailableLocales() {
        return LocaleData.getAvailableLocales("LocaleString");
    }

    /**
     * Returns a list of all 2-letter country codes defined in ISO 3166.
     * Can be used to create Locales.
     */
    public static String[] getISOCountries() {
        if (isoCountries == null) {
            isoCountries = new String[compressedIsoCountries.length() / 6];
            for (int i = 0; i < isoCountries.length; i++)
                isoCountries[i] = compressedIsoCountries.substring((i * 6) + 1, (i * 6) + 3);
        }
        String[] result = new String[isoCountries.length];
        System.arraycopy(isoCountries, 0, result, 0, isoCountries.length);
        return result;
    }

    /**
     * Returns a list of all 2-letter language codes defined in ISO 639.
     * Can be used to create Locales.
     * [NOTE:  ISO 639 is not a stable standard-- some languages' codes have changed.
     * The list this function returns includes both the new and the old codes for the
     * languages whose codes have changed.]
     */
    public static String[] getISOLanguages() {
        if (isoLanguages == null) {
            isoLanguages = new String[compressedIsoLanguages.length() / 6];
            for (int i = 0; i < isoLanguages.length; i++)
                isoLanguages[i] = compressedIsoLanguages.substring((i * 6) + 1, (i * 6) + 3);
        }
        String[] result = new String[isoLanguages.length];
        System.arraycopy(isoLanguages, 0, result, 0, isoLanguages.length);
        return result;
    }

    /**
     * Returns the language code for this locale, which will either be the empty string
     * or a lowercase ISO 639 code.
     * <p>NOTE:  ISO 639 is not a stable standard-- some languages' codes have changed.
     * Locale's constructor recognizes both the new and the old codes for the languages
     * whose codes have changed, but this function always returns the old code.  If you
     * want to check for a specific language whose code has changed, don't do <pre>
     * if (locale.getLanguage().equals("he")
     *    ...
     * </pre>Instead, do<pre>
     * if (locale.getLanguage().equals(new Locale("he", "", "").getLanguage())
     *    ...</pre>
     * @see #getDisplayLanguage
     */
    public String getLanguage() {
        return language;
    }

    /**
     * Returns the country/region code for this locale, which will either be the empty string
     * or an upercase ISO 3166 2-letter code.
     * @see #getDisplayCountry
     */
    public String getCountry() {
        return country;
    }

    /**
     * Returns the variant code for this locale.
     * @see #getDisplayVariant
     */
    public String getVariant() {
        return variant;
    }

    /**
     * Getter for the programmatic name of the entire locale,
     * with the language, country and variant separated by underbars.
     * Language is always lower case, and country is always upper case.
     * If the language is missing, the string will begin with an underbar.
     * If both the language and country fields are missing, this function
     * will return the empty string, even if the variant field is filled in
     * (you can't have a locale with just a variant-- the variant must accompany
     * a valid language or country code).
     * Examples: "en", "de_DE", "_GB", "en_US_WIN", "de__POSIX", "fr__MAC"
     * @see #getDisplayName
     */
    public final String toString() {
        boolean l = language.length() != 0;
        boolean c = country.length() != 0;
        boolean v = variant.length() != 0;
        StringBuffer result = new StringBuffer(language);
        if (c||(l&&v)) {
            result.append('_').append(country); // This may just append '_'
        }
        if (v&&(l||c)) {
            result.append('_').append(variant);
        }
        return result.toString();
    }

    /**
     * Returns a three-letter abbreviation for this locale's language.  If the locale
     * doesn't specify a language, this will be the empty string.  Otherwise, this will
     * be a lowercase ISO 639-2/T language code.
     * The ISO 639-2 language codes can be found on-line at
     *   <a href="ftp://dkuug.dk/i18n/iso-639-2.txt"><code>ftp://dkuug.dk/i18n/iso-639-2.txt</code></a>
     * @exception MissingResourceException Throws MissingResourceException if the
     * three-letter language abbreviation is not available for this locale.
     */
    public String getISO3Language() throws MissingResourceException {
        int length = language.length();

        if (length == 0) {
            return "";
        }

        int index = compressedIsoLanguages.indexOf("," + language);
        if (index == -1 || length != 2) {
            throw new MissingResourceException("Couldn't find 3-letter language code for "
                    + language, "LocaleElements_" + toString(), "ShortLanguage");
        }
        return compressedIsoLanguages.substring(index + 3, index + 6);
    }

    /**
     * Returns a three-letter abbreviation for this locale's country.  If the locale
     * doesn't specify a country, this will be tbe the empty string.  Otherwise, this will
     * be an uppercase ISO 3166 3-letter country code.
     * @exception MissingResourceException Throws MissingResourceException if the
     * three-letter country abbreviation is not available for this locale.
     */
    public String getISO3Country() throws MissingResourceException {
        int length = country.length();

        if (length == 0) {
            return "";
        }

        int index = compressedIsoCountries.indexOf("," + country);
        if (index == -1 || length != 2) {
            throw new MissingResourceException("Couldn't find 3-letter country code for "
                    + country, "LocaleElements_" + toString(), "ShortCountry");
        }
        return compressedIsoCountries.substring(index + 3, index + 6);
    }

    /**
     * Returns a name for the locale's language that is appropriate for display to the
     * user.
     * If possible, the name returned will be localized for the default locale.
     * For example, if the locale is fr_FR and the default locale
     * is en_US, getDisplayLanguage() will return "French"; if the locale is en_US and
     * the default locale is fr_FR, getDisplayLanguage() will return "anglais".
     * If the name returned cannot be localized for the default locale,
     * (say, we don't have a Japanese name for Croatian),
     * this function falls back on the English name, and uses the ISO code as a last-resort
     * value.  If the locale doesn't specify a language, this function returns the empty string.
     */
    public final String getDisplayLanguage() {
        return getDisplayLanguage(getDefault());
    }

    /**
     * Returns a name for the locale's language that is appropriate for display to the
     * user.
     * If possible, the name returned will be localized according to inLocale.
     * For example, if the locale is fr_FR and inLocale
     * is en_US, getDisplayLanguage() will return "French"; if the locale is en_US and
     * inLocale is fr_FR, getDisplayLanguage() will return "anglais".
     * If the name returned cannot be localized according to inLocale,
     * (say, we don't have a Japanese name for Croatian),
     * this function falls back on the default locale, on the English name, and finally
     * on the ISO code as a last-resort value.  If the locale doesn't specify a language,
     * this function returns the empty string.
     */
    public String getDisplayLanguage(Locale inLocale) {
        String  langCode = language;
        if (langCode.length() == 0)
            return "";

        Locale  workingLocale = (Locale)inLocale.clone();
        String  result = null;
        int     phase = 0;
        boolean done = false;

        if (workingLocale.variant.length() == 0)
            phase = 1;
        if (workingLocale.country.length() == 0)
            phase = 2;

        while (!done) {
            try {
                ResourceBundle bundle = LocaleData.getLocaleElements(workingLocale);
                result = findStringMatch((String[][])bundle.getObject("Languages"),
                                    langCode, langCode);
                if (result.length() != 0)
                    done = true;
            }
            catch (Exception e) {
                // just fall through
            }

            if (!done) {
                switch (phase) {
                    case 0:
                        workingLocale.variant = "";
                        break;

                    case 1:
                        workingLocale.country = "";
                        break;