001/*
002 * (C) Copyright 2006-2011 Nuxeo SA (http://nuxeo.com/) and others.
003 *
004 * Licensed under the Apache License, Version 2.0 (the "License");
005 * you may not use this file except in compliance with the License.
006 * You may obtain a copy of the License at
007 *
008 *     http://www.apache.org/licenses/LICENSE-2.0
009 *
010 * Unless required by applicable law or agreed to in writing, software
011 * distributed under the License is distributed on an "AS IS" BASIS,
012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
013 * See the License for the specific language governing permissions and
014 * limitations under the License.
015 *
016 * Contributors:
017 *     Nuxeo - initial API and implementation
018 *
019 * $Id$
020 */
021
022package org.nuxeo.osgi.application;
023
024import java.io.File;
025import java.io.IOException;
026import java.lang.reflect.InvocationTargetException;
027import java.lang.reflect.Method;
028import java.net.MalformedURLException;
029import java.net.URL;
030import java.net.URLClassLoader;
031import java.util.ArrayList;
032import java.util.List;
033
034/**
035 * @author <a href="mailto:bs@nuxeo.com">Bogdan Stefanescu</a>
036 */
037public class Main {
038
039    public static void main(String[] args) throws Exception {
040        if (args.length == 0) {
041            System.err.println("No classpath specified");
042            System.exit(10);
043        }
044        ClassLoader cl = Thread.currentThread().getContextClassLoader();
045        if (!(cl instanceof URLClassLoader)) {
046            System.err.println("Not a valid class loader: " + cl);
047            System.exit(10);
048        }
049        ClassLoader parent = cl.getParent();
050        if (parent == null) {
051            parent = ClassLoader.getSystemClassLoader();
052        }
053        RootClassLoader rootLoader = new RootClassLoader(parent, SharedClassLoader.class);
054        SharedClassLoaderImpl classLoader = new SharedClassLoaderImpl(((URLClassLoader) cl).getURLs(), rootLoader);
055        Thread.currentThread().setContextClassLoader(classLoader.getLoader());
056        URL systemBundle = classLoader.getURLs()[0];
057        // build the class path now
058        List<File> cp = buildClassPath(classLoader, args[0]);
059        // make new arguments by removing the first one to pass further
060        String[] tmp = new String[args.length - 1];
061        System.arraycopy(args, 1, tmp, 0, tmp.length);
062        args = tmp;
063        // reload classes from this JAR using a SharedClassLoader
064        Class<?> me = classLoader.loadClass(StandaloneApplication.class.getName());
065        Method main = me.getMethod("main", URL.class, List.class, String[].class);
066        main.invoke(null, systemBundle, cp, args);
067    }
068
069    public static List<File> buildClassPath(SharedClassLoader classLoader, String rawcp) throws IOException {
070        List<File> result = new ArrayList<File>();
071        String[] cp = rawcp.split(":");
072        for (String entry : cp) {
073            File entryFile;
074            if (entry.endsWith("/.")) {
075                entryFile = new File(entry.substring(0, entry.length() - 2));
076                File[] files = entryFile.listFiles();
077                if (files != null) {
078                    for (File file : files) {
079                        result.add(file);
080                        classLoader.addURL(file.toURI().toURL());
081                    }
082                }
083            } else {
084                entryFile = new File(entry);
085                result.add(entryFile);
086                classLoader.addURL(entryFile.toURI().toURL());
087            }
088        }
089        return result;
090    }
091
092    private static class RootClassLoader extends ClassLoader {
093
094        private final Class<?> loaderClass;
095
096        private final String loaderName;
097
098        RootClassLoader(ClassLoader parent, Class<?> loaderClass) {
099            super(parent);
100            this.loaderClass = loaderClass;
101            loaderName = loaderClass.getName();
102        }
103
104        @Override
105        protected Class<?> findClass(String name) throws ClassNotFoundException {
106            if (loaderName.equals(name)) {
107                return loaderClass;
108            }
109            throw new ClassNotFoundException(name);
110        }
111
112    }
113
114}