001    /* CurrencyNameProvider.java -- Providers of localized currency symbols
002       Copyright (C) 2007 Free Software Foundation, Inc.
003    
004    This file is part of GNU Classpath.
005    
006    GNU Classpath is free software; you can redistribute it and/or modify
007    it under the terms of the GNU General Public License as published by
008    the Free Software Foundation; either version 2, or (at your option)
009    any later version.
010    
011    GNU Classpath is distributed in the hope that it will be useful, but
012    WITHOUT ANY WARRANTY; without even the implied warranty of
013    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
014    General Public License for more details.
015    
016    You should have received a copy of the GNU General Public License
017    along with GNU Classpath; see the file COPYING.  If not, write to the
018    Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
019    02110-1301 USA.
020    
021    Linking this library statically or dynamically with other modules is
022    making a combined work based on this library.  Thus, the terms and
023    conditions of the GNU General Public License cover the whole
024    combination.
025    
026    As a special exception, the copyright holders of this library give you
027    permission to link this library with independent modules to produce an
028    executable, regardless of the license terms of these independent
029    modules, and to copy and distribute the resulting executable under
030    terms of your choice, provided that you also meet, for each linked
031    independent module, the terms and conditions of the license of that
032    module.  An independent module is a module which is not derived from
033    or based on this library.  If you modify this library, you may extend
034    this exception to your version of the library, but you are not
035    obligated to do so.  If you do not wish to do so, delete this
036    exception statement from your version. */
037    
038    package java.util.spi;
039    
040    import java.util.Locale;
041    
042    /**
043     * A {@link CurrencyNameProvider} provides localized
044     * versions of the symbols that represent a particular
045     * currency.  Note that currency symbols are regarded
046     * as names, and thus a <code>null</code> value may
047     * be returned, which should be treated as a lack of
048     * support for the specified {@link Locale}.
049     *
050     * @author Andrew John Hughes (gnu_andrew@member.fsf.org)
051     * @since 1.6
052     */
053    public abstract class CurrencyNameProvider
054      extends LocaleServiceProvider
055    {
056    
057      /**
058       * Constructs a new {@link CurrencyNameProvider}.
059       * Provided for implicit invocation by subclasses.
060       */
061      protected CurrencyNameProvider()
062      {
063      }
064    
065      /**
066       * <p>
067       * This method returns the symbol which precedes or follows a
068       * value in this particular currency.  The returned value is
069       * the symbol used to denote the currency in the specified locale.
070       * </p>
071       * <p>
072       * For example, a supplied locale may specify a different symbol
073       * for the currency, due to conflicts with its own currency.
074       * This would be the case with the American currency, the dollar.
075       * Locales that also use a dollar-based currency (e.g. Canada, Australia)
076       * need to differentiate the American dollar using 'US$' rather than '$'.
077       * So, supplying one of these locales to <code>getSymbol()</code> would
078       * return this value, rather than the standard '$'.
079       * </p>
080       * <p>
081       * In cases where there is no such symbol for a particular currency,
082       * <code>null</code> should be returned.
083       * </p>
084       *
085       * @param currencyCode the ISO 4217 currency code, consisting
086       *                     of three uppercase letters from 'A' to 'Z'
087       * @param locale the locale to express the symbol in.
088       * @return the currency symbol, or <code>null</code> if one is
089       *         unavailable.
090       * @throws NullPointerException if the locale is null.
091       * @throws IllegalArgumentException if the currency code is
092       *                                  not in the correct format
093       *                                  or the locale is not one
094       *                                  returned by
095       *                                  {@link getAvailableLocales()}
096       * @see java.util.Currency#getSymbol(java.util.Locale)
097       */
098      public abstract String getSymbol(String currencyCode, Locale locale);
099    
100    }