/**
* Licensed under the Artistic License; you may not use this file
* except in compliance with the License.
* You may obtain a copy of the License at
*
* http://displaytag.sourceforge.net/license.html
*
* THIS PACKAGE IS PROVIDED "AS IS" AND WITHOUT ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
* WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
*/
package org.displaytag.localization;
import java.util.Locale;
import java.util.MissingResourceException;
import java.util.ResourceBundle;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.jsp.PageContext;
import javax.servlet.jsp.jstl.core.Config;
import javax.servlet.jsp.jstl.fmt.LocalizationContext;
import javax.servlet.jsp.tagext.Tag;
import javax.servlet.jsp.tagext.TagSupport;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.taglibs.standard.tag.common.fmt.BundleSupport;
import org.displaytag.Messages;
/**
* JSTL implementation of a resource provider and locale resolver. It will make the <code>titleKey</code> attribute of
* column tag works the same as fmt:message's <code>key property</code>. This tag must be the descendant of a
* <code>fmt:bundle</code> tag in order to use the titleKey. This is just a shortcut, which makes
*
* <pre>
* <display:column titleKey="bar"/>
* </pre>
*
* behave the same as
*
* <pre>
* <c:set var="foo">
* <fmt:message key="bar"/>
* </c:set>
* <display:column title="${foo}"/>
* </pre>
*
* If you don't define either <code>titleKey</code> or <code>titleKey</code> property on your column, first the tag
* will attempt to look up the <code>property</code> property in your ResourceBundle. Failing that, it will fall back
* to the parent class's behavior of just using the property name.
* @author Fabrizio Giustina
* @version $Revision: 1081 $ ($Author: fgiust $)
*/
public class I18nJstlAdapter implements I18nResourceProvider, LocaleResolver
{
/**
* prefix/suffix for missing entries.
*/
public static final String UNDEFINED_KEY = "???"; //$NON-NLS-1$
/**
* logger.
*/
private static Log log = LogFactory.getLog(I18nJstlAdapter.class);
/**
* Instantiates a new I18nJstlAdapter. Throw a NoClassDefFound error if BundleSupport is not available.
*/
public I18nJstlAdapter()
{
// this will check if BundleSupport is available
// if a NoClassDefFound error is thrown, the I18nJstlAdapter will not be used
BundleSupport.class.hashCode();
}
/**
* @see LocaleResolver#resolveLocale(HttpServletRequest)
*/
public Locale resolveLocale(HttpServletRequest request)
{
Locale locale = (Locale) Config.get(request.getSession(), Config.FMT_LOCALE);
if (locale == null)
{
locale = request.getLocale();
}
return locale;
}
/**
* @see I18nResourceProvider#getResource(String, String, Tag, PageContext)
*/
public String getResource(String resourceKey, String defaultValue, Tag tag, PageContext pageContext)
{
// if titleKey isn't defined either, use property
String key = (resourceKey != null) ? resourceKey : defaultValue;
String title = null;
ResourceBundle bundle = null;
// jakarta jstl implementation, there is no other way to get the bundle from the parent fmt:bundle tag
Tag bundleTag = TagSupport.findAncestorWithClass(tag, BundleSupport.class);
if (bundleTag != null)
{
BundleSupport parent = (BundleSupport) bundleTag;
if (key != null)
{
String prefix = parent.getPrefix();
if (prefix != null)
{
key = prefix + key;
}
}
bundle = parent.getLocalizationContext().getResourceBundle();
}
// resin jstl implementation, more versatile (we don't need to look up resin classes)
if (bundle == null)
{
Object cauchoBundle = pageContext.getAttribute("caucho.bundle"); //$NON-NLS-1$
if (cauchoBundle != null && cauchoBundle instanceof LocalizationContext)
{
bundle = ((LocalizationContext) cauchoBundle).getResourceBundle();
// handle prefix just like resin does
String prefix = (String) pageContext.getAttribute("caucho.bundle.prefix"); //$NON-NLS-1$
if (prefix != null)
{
key = prefix + key;
}
}
}
// standard jstl localizationContest
if (bundle == null)
{
// check for the localizationContext in applicationScope, set in web.xml
LocalizationContext localization = BundleSupport.getLocalizationContext(pageContext);
if (localization != null)
{
bundle = localization.getResourceBundle();
}
}
if (bundle != null)
{
try
{
title = bundle.getString(key);
}
catch (MissingResourceException e)
{
log.debug(Messages.getString("Localization.missingkey", key)); //$NON-NLS-1$
// if user explicitely added a titleKey we guess this is an error
if (resourceKey != null)
{
title = UNDEFINED_KEY + resourceKey + UNDEFINED_KEY;
}
}
}
return title;
}
}