    001    /* ========================================================================
    002     * JCommon : a free general purpose class library for the Java(tm) platform
    003     * ========================================================================
    004     *
    005     * (C) Copyright 2000-2008, by Object Refinery Limited and Contributors.
    006     *
    007     * Project Info:  http://www.jfree.org/jcommon/index.html
    008     *
    009     * This library is free software; you can redistribute it and/or modify it
    010     * under the terms of the GNU Lesser General Public License as published by
    011     * the Free Software Foundation; either version 2.1 of the License, or
    012     * (at your option) any later version.
    013     *
    014     * This library is distributed in the hope that it will be useful, but
    015     * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
    016     * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
    017     * License for more details.
    018     *
    019     * You should have received a copy of the GNU Lesser General Public
    020     * License along with this library; if not, write to the Free Software
    021     * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301,
    022     * USA.
    023     *
    024     * [Java is a trademark or registered trademark of Sun Microsystems, Inc.
    025     * in the United States and other countries.]
    026     *
    027     * --------------------------
    028     * ResourceBundleWrapper.java
    029     * --------------------------
    030     * (C)opyright 2008, by Jess Thrysoee and Contributors.
    031     *
    032     * Original Author:  Jess Thrysoee;
    033     * Contributor(s):   David Gilbert (for Object Refinery Limited);
    034     *
    035     * Changes
    036     * -------
    037     * 18-Dec-2008 : Version 1 (JT);
    038     *
    039     */
    040
    041    package org.jfree.util;
    042
    043    import java.net.URL;
    044    import java.net.URLClassLoader;
    045    import java.util.ArrayList;
    046    import java.util.List;
    047    import java.util.Locale;
    048    import java.util.ResourceBundle;
    049
    050    /**
    051     * Wrapper of ResourceBundle.getBundle() methods. This wrapper is introduced to
    052     * avoid a dramatic performance penalty by superfluous resource (and classes
    053     * loaded by Class.forName) lookups on web server in applets.
    054     *
    055     * <pre>
    056     * public class AppletC extends javax.swing.JApplet {
    057     *    public void init() {
    058     *       ResourceBundleWrapper.removeCodeBase(getCodeBase(),
    059     *               (URLClassLoader) getClass().getClassLoader());
    060     *    ...
    061     * </pre>
    062     *
    063     * @see <a href="http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=4243379">
    064     *               Bug ID: 4243379</a>
    065     * @see <a href="http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=4668479">
    066     *               Bug ID: 4668479</a>
    067     *
    068     * @since 1.0.15
    069     */
    070    public class ResourceBundleWrapper {
    071
    072        /**
    073         * A special class loader with no code base lookup.  This field may be
    074         * <code>null</code> (the field is only initialised if removeCodeBase() is
    075         * called from an applet.
    076         */
    077        private static URLClassLoader noCodeBaseClassLoader;
    078
    079        /**
    080         * Private constructor.
    081         */
    082        private ResourceBundleWrapper() {
    083            // all methods are static, no need to instantiate
    084        }
    085
    086        /**
    087         * Instantiate a {@link URLClassLoader} for resource lookups where the
    088         * codeBase URL is removed.  This method is typically called from an
    089         * applet's init() method.  If this method is never called, the
    090         * <code>getBundle()</code> methods map to the standard
    091         * {@link ResourceBundle} lookup methods.
    092         *
    093         * @param codeBase  the codeBase URL.
    094         * @param urlClassLoader  the class loader.
    095         */
    096        public static void removeCodeBase(URL codeBase,
    097                URLClassLoader urlClassLoader) {
    098            List urlsNoBase = new ArrayList();
    099
    100            URL[] urls = urlClassLoader.getURLs();
    101            for (int i = 0; i < urls.length; i++) {
    102                if (! urls[i].sameFile(codeBase)) {
    103                    urlsNoBase.add(urls[i]);
    104                }
    105            }
    106            // substitute the filtered URL list
    107            URL[] urlsNoBaseArray = (URL[]) urlsNoBase.toArray(new URL[0]);
    108            noCodeBaseClassLoader = URLClassLoader.newInstance(urlsNoBaseArray);
    109        }
    110
    111        /**
    112         * Finds and returns the specified resource bundle.
    113         *
    114         * @param baseName  the base name.
    115         *
    116         * @return The resource bundle.
    117         */
    118        public static final ResourceBundle getBundle(String baseName) {
    119            // the noCodeBaseClassLoader is configured by a call to the
    120            // removeCodeBase() method, typically in the init() method of an
    121            // applet...
    122            if (noCodeBaseClassLoader != null) {
    123                return ResourceBundle.getBundle(baseName, Locale.getDefault(),
    124                        noCodeBaseClassLoader);
    125            }
    126            else {
    127                // standard ResourceBundle behaviour
    128                return ResourceBundle.getBundle(baseName);
    129            }
    130        }
    131
    132        /**
    133         * Finds and returns the specified resource bundle.
    134         *
    135         * @param baseName  the base name.
    136         * @param locale  the locale.
    137         *
    138         * @return The resource bundle.
    139         */
    140        public static final ResourceBundle getBundle(String baseName,
    141                Locale locale) {
    142
    143            // the noCodeBaseClassLoader is configured by a call to the
    144            // removeCodeBase() method, typically in the init() method of an
    145            // applet...
    146            if (noCodeBaseClassLoader != null) {
    147                return ResourceBundle.getBundle(baseName, locale,
    148                        noCodeBaseClassLoader);
    149            }
    150            else {
    151                // standard ResourceBundle behaviour
    152                return ResourceBundle.getBundle(baseName, locale);
    153            }
    154        }
    155
    156        /**
    157         * Maps directly to <code>ResourceBundle.getBundle(baseName, locale,
    158         * loader)</code>.
    159         *
    160         * @param baseName  the base name.
    161         * @param locale  the locale.
    162         * @param loader  the class loader.
    163         *
    164         * @return The resource bundle.
    165         */
    166        public static ResourceBundle getBundle(String baseName, Locale locale,
    167                ClassLoader loader) {
    168            return ResourceBundle.getBundle(baseName, locale, loader);
    169        }
    170
    171    }