CurrencyNameProviderImpl.java

/*
 * Copyright (c) 2012, 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.util.Locale;
import java.util.ResourceBundle;
import java.util.Set;
import java.util.spi.CurrencyNameProvider;

/**
 * Concrete implementation of the
 * {@link java.util.spi.CurrencyNameProvider CurrencyNameProvider} class
 * for the JRE LocaleProviderAdapter.
 *
 * @author Naoto Sato
 * @author Masayoshi Okutsu
 */
public class CurrencyNameProviderImpl extends CurrencyNameProvider
                                      implements AvailableLanguageTags {
    private final LocaleProviderAdapter.Type type;
    private final Set<String> langtags;

    public CurrencyNameProviderImpl(LocaleProviderAdapter.Type type, Set<String> langtags) {
        this.type = type;
        this.langtags = langtags;
    }

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

    /**
     * Gets the symbol of the given currency code for the specified locale.
     * For example, for "USD" (US Dollar), the symbol is "$" if the specified
     * locale is the US, while for other locales it may be "US$". If no
     * symbol can be determined, null should be returned.
     *
     * @param currencyCode the ISO 4217 currency code, which
     *     consists of three upper-case letters between 'A' (U+0041) and
     *     'Z' (U+005A)
     * @param locale the desired locale
     * @return the symbol of the given currency code for the specified locale, or null if
     *     the symbol is not available for the locale
     * @exception NullPointerException if <code>currencyCode</code> or
     *     <code>locale</code> is null
     * @exception IllegalArgumentException if <code>currencyCode</code> is not in
     *     the form of three upper-case letters, or <code>locale</code> isn't
     *     one of the locales returned from
     *     {@link java.util.spi.LocaleServiceProvider#getAvailableLocales()
     *     getAvailableLocales()}.
     * @see java.util.Currency#getSymbol(java.util.Locale)
     */
    @Override
    public String getSymbol(String currencyCode, Locale locale) {
        return getString(currencyCode.toUpperCase(Locale.ROOT), locale);
    }

    /**
     * Returns a name for the currency that is appropriate for display to the
     * user.  The default implementation returns null.
     *
     * @param currencyCode the ISO 4217 currency code, which
     *     consists of three upper-case letters between 'A' (U+0041) and
     *     'Z' (U+005A)
     * @param locale the desired locale
     * @return the name for the currency that is appropriate for display to the
     *     user, or null if the name is not available for the locale
     * @exception IllegalArgumentException if <code>currencyCode</code> is not in
     *     the form of three upper-case letters, or <code>locale</code> isn't
     *     one of the locales returned from
     *     {@link java.util.spi.LocaleServiceProvider#getAvailableLocales()
     *     getAvailableLocales()}.
     * @exception NullPointerException if <code>currencyCode</code> or
     *     <code>locale</code> is <code>null</code>
     * @since 1.7
     */
    @Override
    public String getDisplayName(String currencyCode, Locale locale) {
        return getString(currencyCode.toLowerCase(Locale.ROOT), locale);
    }

    private String getString(String key, Locale locale) {
        if (locale == null) {
            throw new NullPointerException();
        }

        ResourceBundle bundle = LocaleProviderAdapter.forType(type).getLocaleData().getCurrencyNames(locale);
        if (bundle.containsKey(key)) {
                return bundle.getString(key);
            }

        return null;
    }
}