jfreechart example source code file (ResourceBundleWrapper.java)

This example jfreechart source code file (ResourceBundleWrapper.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Java - jfreechart tags/keywords

arraylist, classloader, list, locale, locale, net, network, resourcebundle, resourcebundle, resourcebundlewrapper, resourcebundlewrapper, url, url, urlclassloader, util

The jfreechart ResourceBundleWrapper.java source code

/* ===========================================================
 * JFreeChart : a free chart library for the Java(tm) platform
 * ===========================================================
 *
 * (C) Copyright 2000-2008, by Object Refinery Limited and Contributors.
 *
 * Project Info:  http://www.jfree.org/jfreechart/index.html
 *
 * 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., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301,
 * USA.
 *
 * [Java is a trademark or registered trademark of Sun Microsystems, Inc.
 * in the United States and other countries.]
 *
 * --------------------------
 * ResourceBundleWrapper.java
 * --------------------------
 * (C)opyright 2008, by Jess Thrysoee and Contributors.
 *
 * Original Author:  Jess Thrysoee;
 * Contributor(s):   David Gilbert (for Object Refinery Limited);
 *
 * Changes
 * -------
 * 18-Dec-2008 : Version 1 (JT);
 *
 */

package org.jfree.chart.util;

import java.net.URL;
import java.net.URLClassLoader;
import java.util.ArrayList;
import java.util.List;
import java.util.Locale;
import java.util.ResourceBundle;

/**
 * Wrapper of ResourceBundle.getBundle() methods. This wrapper is introduced to
 * avoid a dramatic performance penalty by superfluous resource (and classes
 * loaded by Class.forName) lookups on web server in applets.
 *
 * <pre>
 * public class AppletC extends javax.swing.JApplet {
 *    public void init() {
 *       ResourceBundleWrapper.removeCodeBase(getCodeBase(),
 *               (URLClassLoader) getClass().getClassLoader());
 *    ...
 * </pre>
 *
 * @see <a href="http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=4243379">
 *               Bug ID: 4243379</a>
 * @see <a href="http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=4668479">
 *               Bug ID: 4668479</a>
 *
 * @since 1.0.12
 */
public class ResourceBundleWrapper {

    /**
     * A special class loader with no code base lookup.  This field may be
     * <code>null (the field is only initialised if removeCodeBase() is
     * called from an applet.
     */
    private static URLClassLoader noCodeBaseClassLoader;

    /**
     * Private constructor.
     */
    private ResourceBundleWrapper() {
        // all methods are static, no need to instantiate
    }

    /**
     * Instantiate a {@link URLClassLoader} for resource lookups where the
     * codeBase URL is removed.  This method is typically called from an
     * applet's init() method.  If this method is never called, the
     * <code>getBundle() methods map to the standard
     * {@link ResourceBundle} lookup methods.
     *
     * @param codeBase  the codeBase URL.
     * @param urlClassLoader  the class loader.
     */
    public static void removeCodeBase(URL codeBase,
            URLClassLoader urlClassLoader) {
        List urlsNoBase = new ArrayList();

        URL[] urls = urlClassLoader.getURLs();
        for (int i = 0; i < urls.length; i++) {
            if (! urls[i].sameFile(codeBase)) {
                urlsNoBase.add(urls[i]);
            }
        }
        // substitute the filtered URL list
        URL[] urlsNoBaseArray = (URL[]) urlsNoBase.toArray(new URL[0]);
        noCodeBaseClassLoader = URLClassLoader.newInstance(urlsNoBaseArray);
    }

    /**
     * Finds and returns the specified resource bundle.
     *
     * @param baseName  the base name.
     *
     * @return The resource bundle.
     */
    public static final ResourceBundle getBundle(String baseName) {
        // the noCodeBaseClassLoader is configured by a call to the
        // removeCodeBase() method, typically in the init() method of an
        // applet...
        if (noCodeBaseClassLoader != null) {
            return ResourceBundle.getBundle(baseName, Locale.getDefault(),
                    noCodeBaseClassLoader);
        }
        else {
            // standard ResourceBundle behaviour
            return ResourceBundle.getBundle(baseName);
        }
    }

    /**
     * Finds and returns the specified resource bundle.
     *
     * @param baseName  the base name.
     * @param locale  the locale.
     *
     * @return The resource bundle.
     */
    public static final ResourceBundle getBundle(String baseName,
            Locale locale) {

        // the noCodeBaseClassLoader is configured by a call to the
        // removeCodeBase() method, typically in the init() method of an
        // applet...
        if (noCodeBaseClassLoader != null) {
            return ResourceBundle.getBundle(baseName, locale,
                    noCodeBaseClassLoader);
        }
        else {
            // standard ResourceBundle behaviour
            return ResourceBundle.getBundle(baseName, locale);
        }
    }

    /**
     * Maps directly to <code>ResourceBundle.getBundle(baseName, locale,
     * loader)</code>.
     *
     * @param baseName  the base name.
     * @param locale  the locale.
     * @param loader  the class loader.
     *
     * @return The resource bundle.
     */
    public static ResourceBundle getBundle(String baseName, Locale locale,
            ClassLoader loader) {
        return ResourceBundle.getBundle(baseName, locale, loader);
    }

}