/*
* $Header: /home/projects/jaxen/scm/jaxen/src/java/main/org/jaxen/function/ext/LocaleFunctionSupport.java,v 1.10 2006/02/05 21:47:42 elharo Exp $
* $Revision: 1.10 $
* $Date: 2006/02/05 21:47:42 $
*
* ====================================================================
*
* Copyright 2000-2002 bob mcwhirter & James Strachan.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are
* met:
*
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* * Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* * Neither the name of the Jaxen Project nor the names of its
* contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
* IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
* TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
* PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER
* OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
* ====================================================================
* This software consists of voluntary contributions made by many
* individuals on behalf of the Jaxen Project and was originally
* created by bob mcwhirter <bob@werken.com> and
* James Strachan <jstrachan@apache.org>. For more information on the
* Jaxen Project, please see <http://www.jaxen.org/>.
*
* $Id: LocaleFunctionSupport.java,v 1.10 2006/02/05 21:47:42 elharo Exp $
*/
package org.orbeon.jaxen.function.ext;
import org.orbeon.jaxen.Function;
import org.orbeon.jaxen.Navigator;
import org.orbeon.jaxen.function.StringFunction;
import java.util.List;
import java.util.Locale;
import java.util.StringTokenizer;
/**
* <p>An abstract base class for Locale-specific extension
* functions. This class provides convenience methods that
* can be inherited, specifically to find a Locale from
* an XPath function argument value.
* </p>
*
* @author <a href="mailto:jstrachan@apache.org">James Strachan</a>
*/
public abstract class LocaleFunctionSupport implements Function
{
/**
* Attempts to convert the given function argument value
* into a Locale either via casting, extracting it from a List
* or looking up the named Locale using reflection.
*
* @param value is either a Locale, a List containing a Locale
* or a String containing the name of a Locale
* as defined by the Locale static members.
*
* @return the Locale for the value or null if one could
* not be deduced
*/
protected Locale getLocale(Object value, Navigator navigator)
{
if (value instanceof Locale)
{
return (Locale) value;
}
else if(value instanceof List)
{
List list = (List) value;
if ( ! list.isEmpty() )
{
return getLocale( list.get(0), navigator );
}
}
else {
String text = StringFunction.evaluate( value, navigator );
if (text != null && text.length() > 0)
{
return findLocale( text );
}
}
return null;
}
/**
* Tries to find a Locale instance by name using
* <a href="http://www.ietf.org/rfc/rfc3066.txt" target="_top">RFC 3066</a>
* language tags such as 'en', 'en-US', 'en-US-Brooklyn'.
*
* @param localeText the RFC 3066 language tag
* @return the locale for the given text or null if one could not
* be found
*/
protected Locale findLocale(String localeText) {
StringTokenizer tokens = new StringTokenizer( localeText, "-" );
if (tokens.hasMoreTokens())
{
String language = tokens.nextToken();
if (! tokens.hasMoreTokens())
{
return findLocaleForLanguage(language);
}
else
{
String country = tokens.nextToken();
if (! tokens.hasMoreTokens())
{
return new Locale(language, country);
}
else
{
String variant = tokens.nextToken();
return new Locale(language, country, variant);
}
}
}
return null;
}
/**
* Finds the locale with the given language name with no country
* or variant, such as Locale.ENGLISH or Locale.FRENCH
*
* @param language the language code to look for
* @return the locale for the given language or null if one could not
* be found
*/
protected Locale findLocaleForLanguage(String language) {
Locale[] locales = Locale.getAvailableLocales();
for ( int i = 0, size = locales.length; i < size; i++ )
{
Locale locale = locales[i];
if ( language.equals( locale.getLanguage() ) )
{
String country = locale.getCountry();
if ( country == null || country.length() == 0 )
{
String variant = locale.getVariant();
if ( variant == null || variant.length() == 0 )
{
return locale;
}
}
}
}
return null;
}
}