Glassfish example source code file (ModuleExtractor.java)

This example Glassfish source code file (ModuleExtractor.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 - Glassfish tags/keywords

enumeration, io, ioexception, ioexception, iterator, jarentry, jarentry, jarentry_prefix, jarfile, jaroutputstream, log, logging, nio, osgimodule, osgimodule, pipedoutputstream, string, string, util, zip

The Glassfish ModuleExtractor.java source code

/*
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
 *
 * Copyright (c) 2010 Oracle and/or its affiliates. All rights reserved.
 *
 * The contents of this file are subject to the terms of either the GNU
 * General Public License Version 2 only ("GPL") or the Common Development
 * and Distribution License("CDDL") (collectively, the "License").  You
 * may not use this file except in compliance with the License.  You can
 * obtain a copy of the License at
 * https://glassfish.dev.java.net/public/CDDL+GPL_1_1.html
 * or packager/legal/LICENSE.txt.  See the License for the specific
 * language governing permissions and limitations under the License.
 *
 * When distributing the software, include this License Header Notice in each
 * file and include the License file at packager/legal/LICENSE.txt.
 *
 * GPL Classpath Exception:
 * Oracle designates this particular file as subject to the "Classpath"
 * exception as provided by Oracle in the GPL Version 2 section of the License
 * file that accompanied this code.
 *
 * Modifications:
 * If applicable, add the following below the License Header, with the fields
 * enclosed by brackets [] replaced by your own identifying information:
 * "Portions Copyright [year] [name of copyright owner]"
 *
 * Contributor(s):
 * If you wish your version of this file to be governed by only the CDDL or
 * only the GPL Version 2, indicate your decision by adding "[Contributor]
 * elects to include this software in this distribution under the [CDDL or GPL
 * Version 2] license."  If you don't indicate a single choice of license, a
 * recipient has the option to distribute your version of this file under
 * either the CDDL, the GPL Version 2 or to extend the choice of license to
 * its licensees as provided above.  However, if you add GPL Version 2 code
 * and therefore, elected the GPL Version 2 license, then the option applies
 * only if the new code is made subject to such option by the copyright
 * holder.
 */

package org.glassfish.uberjar.osgimain;

import java.io.*;
import java.nio.ByteBuffer;
import java.nio.channels.Channels;
import java.nio.channels.ReadableByteChannel;
import java.nio.channels.WritableByteChannel;
import java.util.Enumeration;
import java.util.Iterator;
import java.util.jar.*;
import java.util.logging.Level;
import java.util.logging.Logger;
import java.util.zip.Deflater;
import java.util.zip.ZipEntry;

/**
 * @author bhavanishankar@dev.java.net
 */

public class ModuleExtractor {

    private static final Logger logger = Logger.getLogger("embedded-glassfish");

    private static String MODULES_DIR_PREFIX = "modules";
    private static String MODULES_DIR_SUFFIX = "_jar/";
    private static final char SLASH = '/';
    private static final String JARFILE_URL_PREFIX = "jar:file:";
    private static final String JARENTRY_PREFIX = "!/";
    private static final int BYTEBUFFER_SIZE = 10240;

    /**
     * Extracts the OSGI Modules from the Jar file.
     *
     * @param modulesJarFile Jar file containing the modules.
     * @return Iterable list of OSGIModule
     */
    public static Iterable<OSGIModule> extractModules(File modulesJarFile) {

        final JarFile modulesJar;
        final Enumeration<JarEntry> entries;
        try {
            modulesJar = new JarFile(modulesJarFile);
            entries = modulesJar.entries();
        } catch (Exception ex) {
            logger.log(Level.WARNING, ex.getMessage(), ex);
            return null;
        }

        return new Iterable<OSGIModule>() {

            public Iterator<OSGIModule> iterator() {

                return new Iterator<OSGIModule>() {

                    JarEntry nextEntry = getNextEntry();

                    public boolean hasNext() {
                        return nextEntry != null;
                    }

                    public OSGIModule next() {
                        OSGIModule b = null;

                        try {
                            b = getModule(nextEntry.getName(), modulesJar);
                        } catch (IOException ex) {

                        }
                        nextEntry = getNextEntry();
                        return b;
                    }

                    public void remove() {
                        throw new UnsupportedOperationException(
                                "Removal via iterator is not supported");
                    }

                    private JarEntry getNextEntry() {
                        JarEntry nextEntry = null;

                        while (entries.hasMoreElements()) {
                            JarEntry entry = entries.nextElement();

                            if (!entry.isDirectory()) {
                                continue;
                            }

//                            if (entry.getName().split("/").length != 2) {
//                                continue;
//                            }

                            if (!entry.getName().startsWith(MODULES_DIR_PREFIX) ||
                                    !entry.getName().endsWith(MODULES_DIR_SUFFIX)) {
                                continue;
                            }
                            nextEntry = entry;
                            break;
                        }
                        return nextEntry;
                    }
                };
            }
        };
    }

    /**
     * Extracts a specified module from the modulesJar
     *
     * @param modulePath Path of the module to be extracted eg., modules/module_1/
     * @param modulesJar Jar file containing the modules.
     * @return Extracted OSGIModule.
     * @throws IOException if an I/O error has occurred
     */
    public static OSGIModule getModule(final String modulePath,
                                       final JarFile modulesJar) throws IOException {

        final PipedOutputStream pos = new PipedOutputStream();
        final PipedInputStream pis = new PipedInputStream(pos);

        final OSGIModule b = new OSGIModule();
        b.setContentStream(pis);
        b.setLocation(JARFILE_URL_PREFIX + modulesJar.getName() +
                JARENTRY_PREFIX + modulePath);

        new Thread() {

            @Override
            public void run() {

                try {
                    ZipEntry manifestEntry = modulesJar.getEntry(
                            modulePath + JarFile.MANIFEST_NAME);
                    Manifest m;
                    InputStream in = modulesJar.getInputStream(manifestEntry);


                    try {
                        m = new Manifest(in);
                        if(m != null) {
                            Attributes attrs = m.getMainAttributes();
                            if(attrs != null) {
                                b.setBundleSymbolicName(attrs.getValue("Bundle-SymbolicName"));
                            }
                        }
                    } finally {
                        in.close();
                    }

                    final JarOutputStream jos = new JarOutputStream(pos, m);
                    jos.setLevel(Deflater.NO_COMPRESSION);
                    final ByteBuffer buf = ByteBuffer.allocate(BYTEBUFFER_SIZE);

                    Enumeration<JarEntry> entries = modulesJar.entries();

                    while (entries.hasMoreElements()) {
                        JarEntry entry = entries.nextElement();

/*
                        if (entry.isDirectory()) {
                            continue;
                        }
*/
                        if (!entry.getName().startsWith(modulePath)) {
                            continue;
                        }
                        if (entry.getName().indexOf(JarFile.MANIFEST_NAME) != -1) {
                            continue;
                        }

                        String entryName = entry.getName();
                        entryName = entryName.substring(modulePath.length());
                        jos.putNextEntry(new JarEntry(entryName));

                        in = modulesJar.getInputStream(entry);
                        try {
                            copy(in, jos, buf);
                        } finally {
                            in.close();
                        }
                        jos.closeEntry();
                    }

                    jos.close();
                    pos.close();

                } catch (IOException ex) {
                    b.getExceptionHandler().handle(ex);
                }
            }
        }.start();

        return b;
    }

    /**
     * Copies input to output. To avoid unnecessary allocation of byte buffers,
     * this method takes a byte buffer as argument. It clears the byte buffer
     * at the end of the operation.
     *
     * @param in
     * @param out
     * @param byteBuffer
     */
    private static void copy(InputStream in, OutputStream out, ByteBuffer byteBuffer)
            throws IOException {
        try {
            ReadableByteChannel inChannel = Channels.newChannel(in);
            WritableByteChannel outChannel = Channels.newChannel(out);

            int read;
            do {
                read = inChannel.read(byteBuffer);
                if (read > 0) {
                    byteBuffer.limit(byteBuffer.position());
                    byteBuffer.rewind();
                    int written = 0;
                    while ((written += outChannel.write(byteBuffer)) < read) {
                        // sometimes channel.write may write partial data,
                        // so ensure that the data is written fully.
                    }
                    if (logger.isLoggable(Level.FINER)) {
                        if (logger.isLoggable(Level.FINER)) {
                            logger.logp(Level.FINE, "JarHelper", "write",
                                    "Copied {0} bytes", new Object[]{read});
                        }
                    }
                    byteBuffer.clear();
                }
            } while (read != -1);
        } finally {
            byteBuffer.clear();
        }
    }

    // Utility method to test the JarHelper.

    public static void main(String[] args) throws Exception {

        int bundleCount = 0;
        for (OSGIModule b : ModuleExtractor.extractModules(new File(args[0]))) {

            ByteArrayOutputStream out = new ByteArrayOutputStream();
            byte[] array = new byte[BYTEBUFFER_SIZE];
            int count;

            while ((count = b.getContentStream().read(array)) != -1) {
                out.write(array, 0, count);
            }

            ++bundleCount;
            logger.info("b.name = " + b.getLocation() + ", b.streamSize = " + out.size());
        }

        logger.info("Total number of bundles = " + bundleCount);
    }


}