/*
 * @(#)Locale.java	1.79 04/05/10
 *
 * Copyright 2004 Sun Microsystems, Inc. All rights reserved.
 * SUN PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 */

/*
 * (C) Copyright Taligent, Inc. 1996, 1997 - All Rights Reserved
 * (C) Copyright IBM Corp. 1996 - 1998 - All Rights Reserved
 *
 * The original version of this source code and documentation
 * is copyrighted and owned by Taligent, Inc., a wholly-owned
 * subsidiary of IBM. These materials are provided under terms
 * of a License Agreement between Taligent and Sun. This technology
 * is protected by multiple US and International patents.
 *
 * This notice and attribution to Taligent may not be removed.
 * Taligent is a registered trademark of Taligent, Inc.
 *
 */

package java.util;

import java.io.*;
import java.security.AccessController;
import java.text.MessageFormat;
import sun.security.action.GetPropertyAction;
import sun.text.resources.LocaleData;

/**
 *
 * A <code>Locale</code> object represents a specific geographical, political,
 * or cultural region. An operation that requires a <code>Locale</code> to perform
 * its task is called <em>locale-sensitive</em> and uses the <code>Locale</code>
 * to tailor information for the user. For example, displaying a number
 * is a locale-sensitive operation--the number should be formatted
 * according to the customs/conventions of the user's native country,
 * region, or culture.
 *
 * <P>
 * Create a <code>Locale</code> object using the constructors in this class:
 * <blockquote>
 * <pre>
 * Locale(String language)
 * Locale(String language, String country)
 * Locale(String language, String country, String variant)
 * </pre>
 * </blockquote>
 * The language argument is a valid <STRONG>ISO Language Code.</STRONG>
 * These codes are the lower-case, two-letter codes as defined by ISO-639.
 * You can find a full list of these codes at a number of sites, such as:
 * <BR><a href ="http://www.loc.gov/standards/iso639-2/englangn.html">
 * <code>http://www.loc.gov/standards/iso639-2/englangn.html</code></a>
 *
 * <P>
 * The country argument is a valid <STRONG>ISO Country Code.</STRONG> These
 * codes are the upper-case, two-letter codes as defined by ISO-3166.
 * You can find a full list of these codes at a number of sites, such as:
 * <BR><a href="http://www.iso.ch/iso/en/prods-services/iso3166ma/02iso-3166-code-lists/list-en1.html">
 * <code>http://www.iso.ch/iso/en/prods-services/iso3166ma/02iso-3166-code-lists/list-en1.html</code></a>
 *
 * <P>
 * The variant argument is a vendor or browser-specific code.
 * For example, use WIN for Windows, MAC for Macintosh, and POSIX for POSIX.
 * Where there are two variants, separate them with an underscore, and
 * put the most important one first. For example, a Traditional Spanish collation
 * might construct a locale with parameters for language, country and variant as:
 * "es", "ES", "Traditional_WIN".
 *
 * <P>
 * Because a <code>Locale</code> object is just an identifier for a region,
 * no validity check is performed when you construct a <code>Locale</code>.
 * If you want to see whether particular resources are available for the
 * <code>Locale</code> you construct, you must query those resources. For
 * example, ask the <code>NumberFormat</code> for the locales it supports
 * using its <code>getAvailableLocales</code> method.
 * <BR><STRONG>Note:</STRONG> When you ask for a resource for a particular
 * locale, you get back the best available match, not necessarily
 * precisely what you asked for. For more information, look at
 * {@link ResourceBundle}.
 *
 * <P>
 * The <code>Locale</code> class provides a number of convenient constants
 * that you can use to create <code>Locale</code> objects for commonly used
 * locales. For example, the following creates a <code>Locale</code> object
 * for the United States:
 * <blockquote>
 * <pre>
 * Locale.US
 * </pre>
 * </blockquote>
 *
 * <P>
 * Once you've created a <code>Locale</code> you can query it for information about
 * itself. Use <code>getCountry</code> to get the ISO Country Code and
 * <code>getLanguage</code> to get the ISO Language Code. You can
 * use <code>getDisplayCountry</code> to get the
 * name of the country suitable for displaying to the user. Similarly,
 * you can use <code>getDisplayLanguage</code> to get the name of
 * the language suitable for displaying to the user. Interestingly,
 * the <code>getDisplayXXX</code> methods are themselves locale-sensitive
 * and have two versions: one that uses the default locale and one
 * that uses the locale specified as an argument.
 *
 * <P>
 * The Java 2 platform provides a number of classes that perform locale-sensitive
 * operations. For example, the <code>NumberFormat</code> class formats
 * numbers, currency, or percentages in a locale-sensitive manner. Classes
 * such as <code>NumberFormat</code> have a number of convenience methods
 * for creating a default object of that type. For example, the
 * <code>NumberFormat</code> class provides these three convenience methods
 * for creating a default <code>NumberFormat</code> object:
 * <blockquote>
 * <pre>
 * NumberFormat.getInstance()
 * NumberFormat.getCurrencyInstance()
 * NumberFormat.getPercentInstance()
 * </pre>
 * </blockquote>
 * These methods have two variants; one with an explicit locale
 * and one without; the latter using the default locale.
 * <blockquote>
 * <pre>
 * NumberFormat.getInstance(myLocale)
 * NumberFormat.getCurrencyInstance(myLocale)
 * NumberFormat.getPercentInstance(myLocale)
 * </pre>
 * </blockquote>
 * A <code>Locale</code> is the mechanism for identifying the kind of object
 * (<code>NumberFormat</code>) that you would like to get. The locale is
 * <STRONG>just</STRONG> a mechanism for identifying objects,
 * <STRONG>not</STRONG> a container for the objects themselves.
 *
 * @see         ResourceBundle
 * @see         java.text.Format
 * @see         java.text.NumberFormat
 * @see         java.text.Collator
 * @author      Mark Davis
 * @since       1.1
 */

public final class Locale implements Cloneable, Serializable {

    /** Useful constant for language.
     */
    static public final Locale ENGLISH = new Locale("en","","");

    /** Useful constant for language.
     */
    static public final Locale FRENCH = new Locale("fr","","");

    /** Useful constant for language.
     */
    static public final Locale GERMAN = new Locale("de","","");

    /** Useful constant for language.
     */
    static public final Locale ITALIAN = new Locale("it","","");

    /** Useful constant for language.
     */
    static public final Locale JAPANESE = new Locale("ja","","");

    /** Useful constant for language.
     */
    static public final Locale KOREAN = new Locale("ko","","");

    /** Useful constant for language.
     */
    static public final Locale CHINESE = new Locale("zh","","");

    /** Useful constant for language.
     */
    static public final Locale SIMPLIFIED_CHINESE = new Locale("zh","CN","");

    /** Useful constant for language.
     */
    static public final Locale TRADITIONAL_CHINESE = new Locale("zh","TW","");

    /** Useful constant for country.
     */
    static public final Locale FRANCE = new Locale("fr","FR","");

    /** Useful constant for country.
     */
    static public final Locale GERMANY = new Locale("de","DE","");

    /** Useful constant for country.
     */
    static public final Locale ITALY = new Locale("it","IT","");

    /** Useful constant for country.
     */
    static public final Locale JAPAN = new Locale("ja","JP","");

    /** Useful constant for country.
     */
    static public final Locale KOREA = new Locale("ko","KR","");

    /** Useful constant for country.
     */
    static public final Locale CHINA = new Locale("zh","CN","");

    /** Useful constant for country.
     */
    static public final Locale PRC = new Locale("zh","CN","");

    /** Useful constant for country.
     */
    static public final Locale TAIWAN = new Locale("zh","TW","");

    /** Useful constant for country.
     */
    static public final Locale UK = new Locale("en","GB","");

    /** Useful constant for country.
     */
    static public final Locale US = new Locale("en","US","");

    /** Useful constant for country.
     */
    static public final Locale CANADA = new Locale("en","CA","");

    /** Useful constant for country.
     */
    static public final Locale CANADA_FRENCH = new Locale("fr","CA","");

    /** serialization ID
     */
    static final long serialVersionUID = 9149081749638150636L;

    /**
     * Construct a locale from language, country, variant.
     * NOTE:  ISO 639 is not a stable standard; some of the language codes it defines
     * (specifically iw, ji, and in) have changed.  This constructor accepts both the
     * old codes (iw, ji, and in) and the new codes (he, yi, and id), but all other
     * API on Locale will return only the OLD codes.
     * @param language lowercase two-letter ISO-639 code.
     * @param country uppercase two-letter ISO-3166 code.
     * @param variant vendor and browser specific code. See class description.
     * @exception NullPointerException thrown if any argument is null.
     */
    public Locale(String language, String country, String variant) {
        this.language = convertOldISOCodes(language);
        this.country = toUpperCase(country).intern();
        this.variant = variant.intern();
    }

    /**
     * Construct a locale from language, country.
     * NOTE:  ISO 639 is not a stable standard; some of the language codes it defines
     * (specifically iw, ji, and in) have changed.  This constructor accepts both the
     * old codes (iw, ji, and in) and the new codes (he, yi, and id), but all other
     * API on Locale will return only the OLD codes.
     * @param language lowercase two-letter ISO-639 code.
     * @param country uppercase two-letter ISO-3166 code.
     * @exception NullPointerException thrown if either argument is null.
     */
    public Locale(String language, String country) {
        this(language, country, "");
    }

    /**
     * Construct a locale from a language code.
     * NOTE:  ISO 639 is not a stable standard; some of the language codes it defines
     * (specifically iw, ji, and in) have changed.  This constructor accepts both the
     * old codes (iw, ji, and in) and the new codes (he, yi, and id), but all other
     * API on Locale will return only the OLD codes.
     * @param language lowercase two-letter ISO-639 code.
     * @exception NullPointerException thrown if argument is null.
     * @since 1.4
     */
    public Locale(String language) {
        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 an array of all installed locales.
     * The array returned must contain at least a <code>Locale</code>
     * instance equal to {@link java.util.Locale#US Locale.US}.
     *
     * @return An array of 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 uppercase 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="http://www.loc.gov/standards/iso639-2/englangn.html"><code>http://www.loc.gov/standards/iso639-2/englangn.html</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 the empty string.  Otherwise, this will
     * be an uppercase ISO 3166 3-letter country code.
     * The ISO 3166-2 country codes can be found on-line at
     *   <a href="http://www.davros.org/misc/iso3166.txt"><code>http://www.davros.org/misc/iso3166.txt</code></a>
     * @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 = new Locale(workingLocale.language,
                                                   workingLocale.country,
                                                   "");
                        break;

                    case 1:
                        workingLocale = new Locale(workingLocale.language,
                                                   "",
                                                   workingLocale.variant);
                        break;

                    case 2:
                        workingLocale = getDefault();
                        break;

                    case 3:
                        workingLocale = new Locale("", "", "");
                        break;

                    default:
                        return langCode;
                }
                phase++;
            }
        }
        return result;
    }

    /**
     * Returns a name for the locale's country 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, getDisplayCountry() will return "France"; if the locale is en_US and
     * the default locale is fr_FR, getDisplayLanguage() will return "Etats-Unis".
     * If the name returned cannot be localized for the default locale,
     * (say, we don't have a Japanese name for Croatia),
     * 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 country, this function returns the empty string.
     */
    public final String getDisplayCountry() {
        return getDisplayCountry(getDefault());
    }

    /**
     * Returns a name for the locale's country 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, getDisplayCountry() will return "France"; if the locale is en_US and
     * inLocale is fr_FR, getDisplayLanguage() will return "Etats-Unis".
     * If the name returned cannot be localized according to inLocale.
     * (say, we don't have a Japanese name for Croatia),
     * 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 country,
     * this function returns the empty string.
     */
    public String getDisplayCountry(Locale inLocale) {
        String  ctryCode = country;
        if (ctryCode.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("Countries"),
                                    ctryCode, ctryCode);
                if (result.length() != 0)
                    done = true;
            }
            catch (Exception e) {
                // just fall through
            }

            if (!done) {
                switch (phase) {
                    case 0:
                        workingLocale = new Locale(workingLocale.language,
                                                   workingLocale.country,
                                                   "");
                        break;

                    case 1:
                        workingLocale = new Locale(workingLocale.language,
                                                   "",
                                                   workingLocale.variant);
                        break;

                    case 2:
                        workingLocale = getDefault();
                        break;

                    case 3:
                        workingLocale = new Locale("", "", "");
                        break;

                    default:
                        return ctryCode;
                }
                phase++;
            }
        }
        return result;
    }

    /**
     * Returns a name for the locale's variant code that is appropriate for display to the
     * user.  If possible, the name will be localized for the default locale.  If the locale
     * doesn't specify a variant code, this function returns the empty string.
     */
    public final String getDisplayVariant() {
        return getDisplayVariant(getDefault());
    }

    /**
     * Returns a name for the locale's variant code that is appropriate for display to the
     * user.  If possible, the name will be localized for inLocale.  If the locale
     * doesn't specify a variant code, this function returns the empty string.
     */
    public String getDisplayVariant(Locale inLocale) {
        if (variant.length() == 0)
            return "";

        ResourceBundle bundle = LocaleData.getLocaleElements(inLocale);

        String names[] = getDisplayVariantArray(bundle);

        // Get the localized patterns for formatting a list, and use
        // them to format the list.
        String[] patterns;
        try {
            patterns = (String[])bundle.getObject("LocaleNamePatterns");
        }
        catch (MissingResourceException e) {
            patterns = null;
        }
        return formatList(patterns, names);
    }

    /**
     * Returns a name for the locale that is appropriate for display to the
     * user.  This will be the values returned by getDisplayLanguage(), getDisplayCountry(),
     * and getDisplayVariant() assembled into a single string.  The display name will have
     * one of the following forms:<p><blockquote>
     * language (country, variant)<p>
     * language (country)<p>
     * language (variant)<p>
     * country (variant)<p>
     * language<p>
     * country<p>
     * variant<p></blockquote>
     * depending on which fields are specified in the locale.  If the language, country,
     * and variant fields are all empty, this function returns the empty string.
     */
    public final String getDisplayName() {
        return getDisplayName(getDefault());
    }

    /**
     * Returns a name for the locale that is appropriate for display to the
     * user.  This will be the values returned by getDisplayLanguage(), getDisplayCountry(),
     * and getDisplayVariant() assembled into a single string.  The display name will have
     * one of the following forms:<p><blockquote>
     * language (country, variant)<p>
     * language (country)<p>
     * language (variant)<p>
     * country (variant)<p>
     * language<p>
     * country<p>
     * variant<p></blockquote>
     * depending on which fields are specified in the locale.  If the language, country,
     * and variant fields are all empty, this function returns the empty string.
     */
    public String getDisplayName(Locale inLocale) {
        ResourceBundle bundle = LocaleData.getLocaleElements(inLocale);

        String languageName = getDisplayLanguage(inLocale);
        String countryName = getDisplayCountry(inLocale);
        String[] variantNames = getDisplayVariantArray(bundle);

        // Get the localized patterns for formatting a display name.
        String[] patterns;
        try {
            patterns = (String[])bundle.getObject("LocaleNamePatterns");
        }
        catch (MissingResourceException e) {
            patterns = null;
        }

        // The display name consists of a main name, followed by qualifiers.
        // Typically, the format is "MainName (Qualifier, Qualifier)" but this
        // depends on what pattern is stored in the display locale.
        String   mainName       = null;
        String[] qualifierNames = null;

        // The main name is the language, or if there is no language, the country.
        // If there is neither language nor country (an anomalous situation) then
        // the display name is simply the variant's display name.
        if (languageName.length() != 0) {
            mainName = languageName;
            if (countryName.length() != 0) {
                qualifierNames = new String[variantNames.length + 1];
                System.arraycopy(variantNames, 0, qualifierNames, 1, variantNames.length);
                qualifierNames[0] = countryName;
            }
            else qualifierNames = variantNames;
        }
        else if (countryName.length() != 0) {
            mainName = countryName;
            qualifierNames = variantNames;
        }
        else {
            return formatList(patterns, variantNames);
        }

        // Create an array whose first element is the number of remaining
        // elements.  This serves as a selector into a ChoiceFormat pattern from
        // the resource.  The second and third elements are the main name and
        // the qualifier; if there are no qualifiers, the third element is
        // unused by the format pattern.
        Object[] displayNames = {
            new Integer(qualifierNames.length != 0 ? 2 : 1),
            mainName,
            // We could also just call formatList() and have it handle the empty
            // list case, but this is more efficient, and we want it to be
            // efficient since all the language-only locales will not have any
            // qualifiers.
            qualifierNames.length != 0 ? formatList(patterns, qualifierNames) : null
        };

        if (patterns != null) {
            return new MessageFormat(patterns[0]).format(displayNames);
        }
        else {
            // If we cannot get the message format pattern, then we use a simple
            // hard-coded pattern.  This should not occur in practice unless the
            // installation is missing some core files (LocaleElements etc.).
            StringBuffer result = new StringBuffer();
            result.append((String)displayNames[1]);
            if (displayNames.length > 2) {
                result.append(" (");
                result.append((String)displayNames[2]);
                result.append(")");
            }
            return result.toString();
        }
    }

    /**
     * Overrides Cloneable
     */
    public Object clone()
    {
        try {
            Locale that = (Locale)super.clone();
            return that;
        } catch (CloneNotSupportedException e) {
            throw new InternalError();
        }
    }

    /**
     * Override hashCode.
     * Since Locales are often used in hashtables, caches the value
     * for speed.
     */
    public int hashCode() {
        int hc = hashCodeValue;
        if (hc == 0) {
            hc = (language.hashCode() << 8) ^ country.hashCode() ^ (variant.hashCode() << 4);
            hashCodeValue = hc;
        }
        return hc;
    }

    // Overrides

    /**
     * Returns true if this Locale is equal to another object.  A Locale is
     * deemed equal to another Locale with identical language, country,
     * and variant, and unequal to all other objects.
     *
     * @return true if this Locale is equal to the specified object.
     */

    public boolean equals(Object obj) {
        if (this == obj)                      // quick check
            return true;
        if (!(obj instanceof Locale))
            return false;
        Locale other = (Locale) obj;
	return language == other.language 
            && country == other.country
            && variant == other.variant;
    }

    // ================= privates =====================================

    // XXX instance and class variables. For now keep these separate, since it is
    // faster to match. Later, make into single string.

    /**
     * @serial
     * @see #getLanguage
     */
    private final String language;

    /**
     * @serial
     * @see #getCountry
     */
    private final String country;

    /**
     * @serial
     * @see #getVariant
     */
    private final String variant;

    /**
     * Placeholder for the object's hash code.  Always -1.
     * @serial
     */
    private volatile int hashcode = -1;        // lazy evaluate

    /**
     * Calculated hashcode to fix 4518797.
     */
    private transient volatile int hashCodeValue = 0;

    private static Locale defaultLocale = null;

    /**
     * Return an array of the display names of the variant.
     * @param bundle the ResourceBundle to use to get the display names
     * @return an array of display names, possible of zero length.
     */
    private String[] getDisplayVariantArray(ResourceBundle bundle) {
        // Split the variant name into tokens separated by '_'.
        StringTokenizer tokenizer = new StringTokenizer(variant, "_");
        String[] names = new String[tokenizer.countTokens()];

        // For each variant token, lookup the display name.  If
        // not found, use the variant name itself.
        for (int i=0; i<names.length; ++i) {
            String token = tokenizer.nextToken();
            try {
                names[i] = (String)bundle.getObject("%%" + token);
            }
            catch (MissingResourceException e) {
                names[i] = token;
            }
        }

        return names;
    }

    /**
     * Format a list with an array of patterns.
     * @param patterns an array of three patterns. The first pattern is not
     * used. The second pattern should create a MessageFormat taking 0-3 arguments
     * and formatting them into a list. The third pattern should take 2 arguments
     * and is used by composeList. If patterns is null, then a the list is
     * formatted by concatenation with the delimiter ','.
     * @param stringList the list of strings to be formatted.
     * @return a string representing the list.
     */
    private static String formatList(String[] patterns, String[] stringList) {
        // If we have no list patterns, compose the list in a simple,
        // non-localized way.
        if (patterns == null) {
            StringBuffer result = new StringBuffer();
            for (int i=0; i<stringList.length; ++i) {
                if (i>0) result.append(',');
                result.append(stringList[i]);
            }
            return result.toString();
        }

        // Compose the list down to three elements if necessary
        if (stringList.length > 3) {
            MessageFormat format = new MessageFormat(patterns[2]);
            stringList = composeList(format, stringList);
        }

        // Rebuild the argument list with the list length as the first element
        Object[] args = new Object[stringList.length + 1];
        System.arraycopy(stringList, 0, args, 1, stringList.length);
        args[0] = new Integer(stringList.length);

        // Format it using the pattern in the resource
        MessageFormat format = new MessageFormat(patterns[1]);
        return format.format(args);
    }

    /**
     * Given a list of strings, return a list shortened to three elements.
     * Shorten it by applying the given format to the first two elements
     * recursively.
     * @param format a format which takes two arguments
     * @param list a list of strings
     * @return if the list is three elements or shorter, the same list;
     * otherwise, a new list of three elements.
     */
    private static String[] composeList(MessageFormat format, String[] list) {
        if (list.length <= 3) return list;

        // Use the given format to compose the first two elements into one
        String[] listItems = { list[0], list[1] };
        String newItem = format.format(listItems);

        // Form a new list one element shorter
        String[] newList = new String[list.length-1];
        System.arraycopy(list, 2, newList, 1, newList.length-1);
        newList[0] = newItem;

        // Recurse
        return composeList(format, newList);
    }

    /**
     * Replace the deserialized Locale object with a newly
     * created object. Older language codes are replaced with newer ISO
     * codes. The country and variant codes are replaced with internalized
     * String copies.
     */
    private Object readResolve() throws java.io.ObjectStreamException {
        return new Locale(language, country, variant);
    }


    /**
     * List of all 2-letter language codes currently defined in ISO 639.
     * (Because the Java VM specification turns an array constant into executable code
     * that generates the array element by element, we keep the array in compressed
     * form in a single string and build the array from it at run time when requested.)
     * [We're now also using this table to store a mapping from 2-letter ISO language codes
     * to 3-letter ISO language codes.  Each group of characters consists of a comma, a
     * 2-letter code, and a 3-letter code.  We look up a 3-letter code by searching for
     * a comma followed by a 2-letter code and then getting the three letters following
     * the 2-letter code.]
     */
    private static String[] isoLanguages = null;
    private static final String compressedIsoLanguages =
        ",aaaar,ababk,aeave,afafr,akaka,amamh,anarg,arara,asasm,avava"
      + ",ayaym,azaze,babak,bebel,bgbul,bhbih,bibis,bmbam,bnben,bobod"
      + ",brbre,bsbos,cacat,ceche,chcha,cocos,crcre,csces,cuchu,cvchv"
      + ",cycym,dadan,dedeu,dvdiv,dzdzo,eeewe,elell,eneng,eoepo,esspa"
      + ",etest,eueus,fafas,ffful,fifin,fjfij,fofao,frfra,fyfry,gagle"
      + ",gdgla,glglg,gngrn,guguj,gvglv,hahau,heheb,hihin,hohmo,hrhrv"
      + ",hthat,huhun,hyhye,hzher,iaina,idind,ieile,igibo,iiiii,ikipk"
      + ",inind,ioido,isisl,itita,iuiku,iwheb,jajpn,jiyid,jvjav,kakat"
      + ",kgkon,kikik,kjkua,kkkaz,klkal,kmkhm,knkan,kokor,krkau,kskas"
      + ",kukur,kvkom,kwcor,kykir,lalat,lbltz,lglug,lilim,lnlin,lolao"
      + ",ltlit,lulub,lvlav,mgmlg,mhmah,mimri,mkmkd,mlmal,mnmon,momol"
      + ",mrmar,msmsa,mtmlt,mymya,nanau,nbnob,ndnde,nenep,ngndo,nlnld"
      + ",nnnno,nonor,nrnbl,nvnav,nynya,ococi,ojoji,omorm,orori,ososs"
      + ",papan,pipli,plpol,pspus,ptpor,quque,rmroh,rnrun,roron,rurus"
      + ",rwkin,sasan,scsrd,sdsnd,sesme,sgsag,sisin,skslk,slslv,smsmo"
      + ",snsna,sosom,sqsqi,srsrp,ssssw,stsot,susun,svswe,swswa,tatam"
      + ",tetel,tgtgk,ththa,titir,tktuk,tltgl,tntsn,toton,trtur,tstso"
      + ",tttat,twtwi,tytah,uguig,ukukr,ururd,uzuzb,veven,vivie,vovol"
      + ",wawln,wowol,xhxho,yiyid,yoyor,zazha,zhzho,zuzul";

    /**
     * List of all 2-letter country codes currently defined in ISO 3166.
     * (Because the Java VM specification turns an array constant into executable code
     * that generates the array element by element, we keep the array in compressed
     * form in a single string and build the array from it at run time when requested.)
     * [We're now also using this table to store a mapping from 2-letter ISO country codes
     * to 3-letter ISO country codes.  Each group of characters consists of a comma, a
     * 2-letter code, and a 3-letter code.  We look up a 3-letter code by searching for
     * a comma followed by a 2-letter code and then getting the three letters following
     * the 2-letter code.]
     */
    private static String[] isoCountries = null;
    private static final String compressedIsoCountries =
        ",ADAND,AEARE,AFAFG,AGATG,AIAIA,ALALB,AMARM,ANANT,AOAGO,AQATA"
      + ",ARARG,ASASM,ATAUT,AUAUS,AWABW,AXALA,AZAZE,BABIH,BBBRB,BDBGD,BEBEL"
      + ",BFBFA,BGBGR,BHBHR,BIBDI,BJBEN,BMBMU,BNBRN,BOBOL,BRBRA,BSBHS"
      + ",BTBTN,BVBVT,BWBWA,BYBLR,BZBLZ,CACAN,CCCCK,CDCOD,CFCAF,CGCOG"
      + ",CHCHE,CICIV,CKCOK,CLCHL,CMCMR,CNCHN,COCOL,CRCRI,CSSCG,CUCUB"
      + ",CVCPV,CXCXR,CYCYP,CZCZE,DEDEU,DJDJI,DKDNK,DMDMA,DODOM,DZDZA"
      + ",ECECU,EEEST,EGEGY,EHESH,ERERI,ESESP,ETETH,FIFIN,FJFJI,FKFLK"
      + ",FMFSM,FOFRO,FRFRA,GAGAB,GBGBR,GDGRD,GEGEO,GFGUF,GHGHA,GIGIB"
      + ",GLGRL,GMGMB,GNGIN,GPGLP,GQGNQ,GRGRC,GSSGS,GTGTM,GUGUM,GWGNB"
      + ",GYGUY,HKHKG,HMHMD,HNHND,HRHRV,HTHTI,HUHUN,IDIDN,IEIRL,ILISR"
      + ",ININD,IOIOT,IQIRQ,IRIRN,ISISL,ITITA,JMJAM,JOJOR,JPJPN,KEKEN"
      + ",KGKGZ,KHKHM,KIKIR,KMCOM,KNKNA,KPPRK,KRKOR,KWKWT,KYCYM,KZKAZ"
      + ",LALAO,LBLBN,LCLCA,LILIE,LKLKA,LRLBR,LSLSO,LTLTU,LULUX,LVLVA"
      + ",LYLBY,MAMAR,MCMCO,MDMDA,MGMDG,MHMHL,MKMKD,MLMLI,MMMMR,MNMNG"
      + ",MOMAC,MPMNP,MQMTQ,MRMRT,MSMSR,MTMLT,MUMUS,MVMDV,MWMWI,MXMEX"
      + ",MYMYS,MZMOZ,NANAM,NCNCL,NENER,NFNFK,NGNGA,NINIC,NLNLD,NONOR"
      + ",NPNPL,NRNRU,NUNIU,NZNZL,OMOMN,PAPAN,PEPER,PFPYF,PGPNG,PHPHL"
      + ",PKPAK,PLPOL,PMSPM,PNPCN,PRPRI,PSPSE,PTPRT,PWPLW,PYPRY,QAQAT"
      + ",REREU,ROROU,RURUS,RWRWA,SASAU,SBSLB,SCSYC,SDSDN,SESWE,SGSGP"
      + ",SHSHN,SISVN,SJSJM,SKSVK,SLSLE,SMSMR,SNSEN,SOSOM,SRSUR,STSTP"
      + ",SVSLV,SYSYR,SZSWZ,TCTCA,TDTCD,TFATF,TGTGO,THTHA,TJTJK,TKTKL"
      + ",TLTLS,TMTKM,TNTUN,TOTON,TRTUR,TTTTO,TVTUV,TWTWN,TZTZA,UAUKR"
      + ",UGUGA,UMUMI,USUSA,UYURY,UZUZB,VAVAT,VCVCT,VEVEN,VGVGB,VIVIR"
      + ",VNVNM,VUVUT,WFWLF,WSWSM,YEYEM,YTMYT,ZAZAF,ZMZMB,ZWZWE";

    /*
     * Locale needs its own, locale insensitive version of toLowerCase to
     * avoid circularity problems between Locale and String.
     * The most straightforward algorithm is used. Look at optimizations later.
     */
    private String toLowerCase(String str) {
	char[] buf = new char[str.length()];
        for (int i = 0; i < buf.length; i++) {
	    buf[i] = Character.toLowerCase(str.charAt(i));
        }
        return new String( buf );
    }

    /*
     * Locale needs its own, locale insensitive version of toUpperCase to
     * avoid circularity problems between Locale and String.
     * The most straightforward algorithm is used. Look at optimizations later.
     */
    private String toUpperCase(String str) {
	char[] buf = new char[str.length()];
        for (int i = 0; i < buf.length; i++) {
	    buf[i] = Character.toUpperCase(str.charAt(i));
        }
        return new String( buf );
    }

    private String findStringMatch(String[][] languages,
                                   String desiredLanguage, String fallbackLanguage)
    {
        for (int i = 0; i < languages.length; ++i)
            if (desiredLanguage.equals(languages[i][0]))
                return languages[i][1];
        if (!fallbackLanguage.equals(desiredLanguage))
            for (int i = 0; i < languages.length; ++i)
                if (fallbackLanguage.equals(languages[i][0]))
                    return languages[i][1];
        if (!"EN".equals(desiredLanguage) && "EN".equals(fallbackLanguage))
            for (int i = 0; i < languages.length; ++i)
                if ("EN".equals(languages[i][0]))
                    return languages[i][1];
        return "";
    }

    private String convertOldISOCodes(String language) {
        // we accept both the old and the new ISO codes for the languages whose ISO
        // codes have changed, but we always store the OLD code, for backward compatibility
        language = toLowerCase(language).intern();
        if (language == "he") {
            return "iw";
        } else if (language == "yi") {
            return "ji";
        } else if (language == "id") {
            return "in";
        } else {
            return language;
        }
    }
}
