de.jakop.lotus.domingo.i18n.ResourceManager Maven / Gradle / Ivy
/*
* This file is part of Domingo
* an Open Source Java-API to Lotus Notes/Domino
* originally hosted at http://domingo.sourceforge.net, now available
* at https://github.com/fjakop/domingo
*
* Copyright (c) 2003-2007 Beck et al. projects GmbH Munich, Germany (http://www.bea.de)
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
package de.jakop.lotus.domingo.i18n;
import java.lang.ref.WeakReference;
import java.util.HashMap;
import java.util.Map;
/**
* Manager for internatialized resources.
*
* @author Kurt Riede
*/
public final class ResourceManager {
/** Permission needed to clear complete cache. */
private static final RuntimePermission CLEAR_CACHE_PERMISSION = new RuntimePermission("i18n.clearCompleteCache");
/** Static cache for resources. */
private static final Map RESOURCES = new HashMap();
/**
* Private Constructor to block instantiation.
*/
private ResourceManager() {
}
/**
* Retrieve resource with specified base name.
*
* @param baseName the base name
* @return the Resources
*/
public static Resources getBaseResources(final String baseName) {
return getBaseResources(baseName, null);
}
/**
* Retrieve resource with specified base name.
*
* @param baseName the base name
* @param classLoader the classLoader to load resources from
* @return the Resources
*/
public static synchronized Resources getBaseResources(final String baseName, final ClassLoader classLoader) {
Resources theResources = getCachedResource(baseName);
if (null == theResources) {
theResources = new Resources(baseName, classLoader);
putCachedResource(baseName, theResources);
}
return theResources;
}
/**
* Clear the cache of all resources currently loaded into the
* system. This method is useful if you need to dump the complete
* cache and because part of the application is reloading and
* thus the resources may need to be reloaded.
*
* Note that the caller must have been granted the
* "i18n.clearCompleteCache" {@link RuntimePermission} or
* else a security exception will be thrown.
*
* @throws SecurityException if the caller does not have
* permission to clear cache
*/
public static synchronized void clearResourceCache() throws SecurityException {
final SecurityManager sm = System.getSecurityManager();
if (null != sm) {
sm.checkPermission(CLEAR_CACHE_PERMISSION);
}
RESOURCES.clear();
}
/**
* Cache specified resource in weak reference.
*
* @param baseName the resource key
* @param theResources the resources object
*/
private static synchronized void putCachedResource(final String baseName, final Resources theResources) {
RESOURCES.put(baseName, new WeakReference(theResources));
}
/**
* Retrieve cached resource.
*
* @param baseName the resource key
* @return resources the resources object
*/
private static synchronized Resources getCachedResource(final String baseName) {
final WeakReference weakReference = (WeakReference) RESOURCES.get(baseName);
if (null != weakReference) {
return (Resources) weakReference.get();
}
return null;
}
/**
* Retrieve resource for specified name.
* The base name is determined by name postfixed with ".Resources".
*
* @param name the name to use when looking up resources
* @return the Resources
*/
public static Resources getResources(final String name) {
return getBaseResources(name + ".Resources");
}
/**
* Retrieve resource for specified Classes package.
* The base name is determined by name of classes package
* postfixed with ".Resources".
*
* @param clazz the Class
* @return the Resources
*/
public static Resources getPackageResources(final Class clazz) {
return getBaseResources(getPackageResourcesBaseName(clazz), clazz.getClassLoader());
}
/**
* Retrieve resource for specified Class.
* The base name is determined by name of Class
* postfixed with "Resources".
*
* @param clazz the Class
* @return the Resources
*/
public static Resources getClassResources(final Class clazz) {
return getBaseResources(getClassResourcesBaseName(clazz), clazz.getClassLoader());
}
/**
* Retrieve resource base name for specified Classes package.
* The base name is determined by name of classes package
* postfixed with ".Resources".
*
* @param clazz the Class
* @return the resource base name
*/
public static String getPackageResourcesBaseName(final Class clazz) {
final Package pkg = clazz.getPackage();
String baseName;
if (null == pkg) {
final String name = clazz.getName();
if (-1 == name.lastIndexOf(".")) {
baseName = "Resources";
} else {
baseName = name.substring(0, name.lastIndexOf(".")) + ".Resources";
}
} else {
baseName = pkg.getName() + ".Resources";
}
return baseName;
}
/**
* Retrieve resource base name for specified Class.
* The base name is determined by name of Class
* postfixed with "Resources".
*
* @param clazz the Class
* @return the resource base name
*/
public static String getClassResourcesBaseName(final Class clazz) {
return clazz.getName() + "Resources";
}
}