jurt/com/sun/star/comp/loader/RegistrationClassFinder.java

   1 /* -*- Mode: Java; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
   2 /*
   3  * This file is part of the LibreOffice project.
   4  *
   5  * This Source Code Form is subject to the terms of the Mozilla Public
   6  * License, v. 2.0. If a copy of the MPL was not distributed with this
   7  * file, You can obtain one at http://mozilla.org/MPL/2.0/.
   8  *
   9  * This file incorporates work covered by the following license notice:
  10  *
  11  *   Licensed to the Apache Software Foundation (ASF) under one or more
  12  *   contributor license agreements. See the NOTICE file distributed
  13  *   with this work for additional information regarding copyright
  14  *   ownership. The ASF licenses this file to you under the Apache
  15  *   License, Version 2.0 (the "License"); you may not use this file
  16  *   except in compliance with the License. You may obtain a copy of
  17  *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
  18  */
  19
  20 package com.sun.star.comp.loader;
  21
  22 import com.sun.star.lib.unoloader.UnoClassLoader;
  23 import com.sun.star.lib.util.WeakMap;
  24 import java.io.IOException;
  25 import java.net.URL;
  26 import java.net.URLClassLoader;
  27 import java.util.jar.Attributes;
  28
  29 final class RegistrationClassFinder {
  30     public static Class<?> find(String locationUrl)
  31         throws ClassNotFoundException, IOException
  32     {
  33         synchronized (map) {
  34             Class<?> c = (Class<?>) WeakMap.getValue(map.get(locationUrl));
  35             if (c != null) {
  36                 return c;
  37             }
  38         }
  39         URL url = new URL(locationUrl);
  40         Attributes attr = UnoClassLoader.getJarMainAttributes(url);
  41         String name = attr == null
  42             ? null : attr.getValue("RegistrationClassName");
  43         if (name == null) {
  44             return null;
  45         }
  46         ClassLoader cl1 = RegistrationClassFinder.class.getClassLoader();
  47         ClassLoader cl2;
  48         if (cl1 instanceof UnoClassLoader) {
  49             cl2 = ((UnoClassLoader) cl1).getClassLoader(url, attr);
  50         } else {
  51             cl2 = URLClassLoader.newInstance(new URL[] { url }, cl1);
  52         }
  53         Class<?> c = cl2.loadClass(name);
  54         synchronized (map) {
  55             Class<?> c2 = (Class<?>) WeakMap.getValue(map.get(locationUrl));
  56             if (c2 != null) {
  57                 return c2;
  58             }
  59             map.put(locationUrl, c);
  60         }
  61         return c;
  62     }
  63
  64     private RegistrationClassFinder() {} // do not instantiate
  65
  66     private static final WeakMap map = new WeakMap();
  67 }
  68
  69 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */