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 * Copyright (c) 1999, 2016, 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.io.IOException;
import java.text.BreakIterator;
import java.text.spi.BreakIteratorProvider;
import java.util.Locale;
import java.util.MissingResourceException;
import java.util.Objects;
import java.util.Set;
import sun.text.DictionaryBasedBreakIterator;
import sun.text.RuleBasedBreakIterator;

/**
 * Concrete implementation of the  {@link java.text.spi.BreakIteratorProvider
 * BreakIteratorProvider} class for the JRE LocaleProviderAdapter.
 *
 * @author Naoto Sato
 * @author Masayoshi Okutsu
 */
public class BreakIteratorProviderImpl extends BreakIteratorProvider
                                       implements AvailableLanguageTags {

    private static final int CHARACTER_INDEX = 0;
    private static final int WORD_INDEX = 1;
    private static final int LINE_INDEX = 2;
    private static final int SENTENCE_INDEX = 3;

    private final LocaleProviderAdapter.Type type;
    private final Set<String> langtags;

    public BreakIteratorProviderImpl(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);
    }

    /**
     * Returns a new <code>BreakIterator</code> instance
     * for <a href="../BreakIterator.html#word">word breaks</a>
     * for the given locale.
     * @param locale the desired locale
     * @return A break iterator for word breaks
     * @exception NullPointerException if <code>locale</code> is null
     * @exception IllegalArgumentException if <code>locale</code> isn't
     *     one of the locales returned from
     *     {@link java.util.spi.LocaleServiceProvider#getAvailableLocales()
     *     getAvailableLocales()}.
     * @see java.text.BreakIterator#getWordInstance(java.util.Locale)
     */
    @Override
    public BreakIterator getWordInstance(Locale locale) {
        return getBreakInstance(locale,
                                WORD_INDEX,
                                "WordData",
                                "WordDictionary");
    }

    /**
     * Returns a new <code>BreakIterator</code> instance
     * for <a href="../BreakIterator.html#line">line breaks</a>
     * for the given locale.
     * @param locale the desired locale
     * @return A break iterator for line breaks
     * @exception NullPointerException if <code>locale</code> is null
     * @exception IllegalArgumentException if <code>locale</code> isn't
     *     one of the locales returned from
     *     {@link java.util.spi.LocaleServiceProvider#getAvailableLocales()
     *     getAvailableLocales()}.
     * @see java.text.BreakIterator#getLineInstance(java.util.Locale)
     */
    @Override
    public BreakIterator getLineInstance(Locale locale) {
        return getBreakInstance(locale,
                                LINE_INDEX,
                                "LineData",
                                "LineDictionary");
    }

    /**
     * Returns a new <code>BreakIterator</code> instance
     * for <a href="../BreakIterator.html#character">character breaks</a>
     * for the given locale.
     * @param locale the desired locale
     * @return A break iterator for character breaks
     * @exception NullPointerException if <code>locale</code> is null
     * @exception IllegalArgumentException if <code>locale</code> isn't
     *     one of the locales returned from
     *     {@link java.util.spi.LocaleServiceProvider#getAvailableLocales()
     *     getAvailableLocales()}.
     * @see java.text.BreakIterator#getCharacterInstance(java.util.Locale)
     */
    @Override
    public BreakIterator getCharacterInstance(Locale locale) {
        return getBreakInstance(locale,
                                CHARACTER_INDEX,
                                "CharacterData",
                                "CharacterDictionary");
    }

    /**
     * Returns a new <code>BreakIterator</code> instance
     * for <a href="../BreakIterator.html#sentence">sentence breaks</a>
     * for the given locale.
     * @param locale the desired locale
     * @return A break iterator for sentence breaks
     * @exception NullPointerException if <code>locale</code> is null
     * @exception IllegalArgumentException if <code>locale</code> isn't
     *     one of the locales returned from
     *     {@link java.util.spi.LocaleServiceProvider#getAvailableLocales()
     *     getAvailableLocales()}.
     * @see java.text.BreakIterator#getSentenceInstance(java.util.Locale)
     */
    @Override
    public BreakIterator getSentenceInstance(Locale locale) {
        return getBreakInstance(locale,
                                SENTENCE_INDEX,
                                "SentenceData",
                                "SentenceDictionary");
    }

    private BreakIterator getBreakInstance(Locale locale,
                                           int type,
                                           String ruleName,
                                           String dictionaryName) {
        Objects.requireNonNull(locale);

        LocaleResources lr = LocaleProviderAdapter.forJRE().getLocaleResources(locale);
        String[] classNames = (String[]) lr.getBreakIteratorInfo("BreakIteratorClasses");
        String ruleFile = (String) lr.getBreakIteratorInfo(ruleName);
        byte[] ruleData = lr.getBreakIteratorResources(ruleName);

        try {
            switch (classNames[type]) {
            case "RuleBasedBreakIterator":
                return new RuleBasedBreakIterator(ruleFile, ruleData);

            case "DictionaryBasedBreakIterator":
                String dictionaryFile = (String) lr.getBreakIteratorInfo(dictionaryName);
                byte[] dictionaryData = lr.getBreakIteratorResources(dictionaryName);
                return new DictionaryBasedBreakIterator(ruleFile, ruleData,
                                                        dictionaryFile, dictionaryData);
            default:
                throw new IllegalArgumentException("Invalid break iterator class \"" +
                                classNames[type] + "\"");
            }
        } catch (MissingResourceException | IllegalArgumentException e) {
            throw new InternalError(e.toString(), e);
        }
    }

    @Override
    public Set<String> getAvailableLanguageTags() {
        return langtags;
    }

    @Override
    public boolean isSupportedLocale(Locale locale) {
        return LocaleProviderAdapter.forType(type).isSupportedProviderLocale(locale, langtags);
    }
}