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 * Copyright (c) 1999, 2017, Oracle and/or its affiliates. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.  Oracle designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Oracle in the LICENSE file that accompanied this code.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

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package sun.util.locale.provider;

import java.text.DateFormat;

import java.text.SimpleDateFormat;

import java.text.spi.DateFormatProvider;

import java.util.Calendar;

import java.util.Locale;

import java.util.MissingResourceException;

import java.util.Set;

import java.util.TimeZone;

/**

 * Concrete implementation of the  {@link java.text.spi.DateFormatProvider

 * DateFormatProvider} class for the JRE LocaleProviderAdapter.

 *

 * @author Naoto Sato

 * @author Masayoshi Okutsu

 */

public class DateFormatProviderImpl extends DateFormatProvider implements AvailableLanguageTags {

    private final LocaleProviderAdapter.Type type;

    private final Set<String> langtags;

    public DateFormatProviderImpl(LocaleProviderAdapter.Type type, Set<String> langtags) {

        this.type = type;

        this.langtags = langtags;

    }

    /**

     * Returns an array of all locales for which this locale service provider

     * can provide localized objects or names.

     *

     * @return An array of all locales for which this locale service provider

     * can provide localized objects or names.

     */

    @Override

    public Locale[] getAvailableLocales() {

        return LocaleProviderAdapter.toLocaleArray(langtags);

    }

    @Override

    public boolean isSupportedLocale(Locale locale) {

        return LocaleProviderAdapter.forType(type).isSupportedProviderLocale(locale, langtags);

    }

    /**

     * Returns a new <code>DateFormat</code> instance which formats time

     * with the given formatting style for the specified locale.

     * @param style the given formatting style.  Either one of

     *     {@link java.text.DateFormat#SHORT DateFormat.SHORT},

     *     {@link java.text.DateFormat#MEDIUM DateFormat.MEDIUM},

     *     {@link java.text.DateFormat#LONG DateFormat.LONG}, or

     *     {@link java.text.DateFormat#FULL DateFormat.FULL}.

     * @param locale the desired locale.

     * @exception IllegalArgumentException if <code>style</code> is invalid,

     *     or if <code>locale</code> isn't

     *     one of the locales returned from

     *     {@link java.util.spi.LocaleServiceProvider#getAvailableLocales()

     *     getAvailableLocales()}.

     * @exception NullPointerException if <code>locale</code> is null

     * @return a time formatter.

     * @see java.text.DateFormat#getTimeInstance(int, java.util.Locale)

     */

    @Override

    public DateFormat getTimeInstance(int style, Locale locale) {

        return getInstance(-1, style, locale);

    }

    /**

     * Returns a new <code>DateFormat</code> instance which formats date

     * with the given formatting style for the specified locale.

     * @param style the given formatting style.  Either one of

     *     {@link java.text.DateFormat#SHORT DateFormat.SHORT},

     *     {@link java.text.DateFormat#MEDIUM DateFormat.MEDIUM},

     *     {@link java.text.DateFormat#LONG DateFormat.LONG}, or

     *     {@link java.text.DateFormat#FULL DateFormat.FULL}.

     * @param locale the desired locale.

     * @exception IllegalArgumentException if <code>style</code> is invalid,

     *     or if <code>locale</code> isn't

     *     one of the locales returned from

     *     {@link java.util.spi.LocaleServiceProvider#getAvailableLocales()

     *     getAvailableLocales()}.

     * @exception NullPointerException if <code>locale</code> is null

     * @return a date formatter.

     * @see java.text.DateFormat#getDateInstance(int, java.util.Locale)

     */

    @Override

    public DateFormat getDateInstance(int style, Locale locale) {

        return getInstance(style, -1, locale);

    }

    /**

     * Returns a new <code>DateFormat</code> instance which formats date and time

     * with the given formatting style for the specified locale.

     * @param dateStyle the given date formatting style.  Either one of

     *     {@link java.text.DateFormat#SHORT DateFormat.SHORT},

     *     {@link java.text.DateFormat#MEDIUM DateFormat.MEDIUM},

     *     {@link java.text.DateFormat#LONG DateFormat.LONG}, or

     *     {@link java.text.DateFormat#FULL DateFormat.FULL}.

     * @param timeStyle the given time formatting style.  Either one of

     *     {@link java.text.DateFormat#SHORT DateFormat.SHORT},

     *     {@link java.text.DateFormat#MEDIUM DateFormat.MEDIUM},

     *     {@link java.text.DateFormat#LONG DateFormat.LONG}, or

     *     {@link java.text.DateFormat#FULL DateFormat.FULL}.

     * @param locale the desired locale.

     * @exception IllegalArgumentException if <code>dateStyle</code> or

     *     <code>timeStyle</code> is invalid,

     *     or if <code>locale</code> isn't

     *     one of the locales returned from

     *     {@link java.util.spi.LocaleServiceProvider#getAvailableLocales()

     *     getAvailableLocales()}.

     * @exception NullPointerException if <code>locale</code> is null

     * @return a date/time formatter.

     * @see java.text.DateFormat#getDateTimeInstance(int, int, java.util.Locale)

     */

    @Override

    public DateFormat getDateTimeInstance(int dateStyle, int timeStyle,

                                          Locale locale) {

        return getInstance(dateStyle, timeStyle, locale);

    }

    private DateFormat getInstance(int dateStyle, int timeStyle, Locale locale) {

        if (locale == null) {

            throw new NullPointerException();

        }

        // Check for region override

        Locale rg = CalendarDataUtility.findRegionOverride(locale);

        SimpleDateFormat sdf = new SimpleDateFormat("", rg);

        Calendar cal = sdf.getCalendar();

        try {

            String pattern = LocaleProviderAdapter.forType(type)

                .getLocaleResources(rg).getDateTimePattern(timeStyle, dateStyle,

                                                               cal);

            sdf.applyPattern(pattern);

        } catch (MissingResourceException mre) {

            // Specify the fallback pattern

            sdf.applyPattern("M/d/yy h:mm a");

        }

        // Check for timezone override

        String tz = locale.getUnicodeLocaleType("tz");

        if (tz != null) {

            sdf.setTimeZone(

                TimeZoneNameUtility.convertLDMLShortID(tz)

                    .map(TimeZone::getTimeZone)

                    .orElseGet(sdf::getTimeZone));

        }

        return sdf;

    }

    @Override

    public Set<String> getAvailableLanguageTags() {

        return langtags;

    }

}