    001/*
    002 * Licensed to the Apache Software Foundation (ASF) under one
    003 * or more contributor license agreements.  See the NOTICE file
    004 * distributed with this work for additional information
    005 * regarding copyright ownership.  The ASF licenses this file
    006 * to you under the Apache License, Version 2.0 (the
    007 * "License"); you may not use this file except in compliance
    008 * with the License.  You may obtain a copy of the License at
    009 *
    010 * http://www.apache.org/licenses/LICENSE-2.0
    011 *
    012 * Unless required by applicable law or agreed to in writing,
    013 * software distributed under the License is distributed on an
    014 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
    015 * KIND, either express or implied.  See the License for the
    016 * specific language governing permissions and limitations
    017 * under the License.
    018 */
    019
    020package org.apache.commons.compress.compressors.pack200;
    021
    022import java.io.File;
    023import java.io.FileOutputStream;
    024import java.io.IOException;
    025import java.io.OutputStream;
    026import java.util.HashMap;
    027import java.util.Map;
    028import java.util.jar.JarFile;
    029import java.util.jar.JarOutputStream;
    030import java.util.jar.Pack200;
    031
    032/**
    033 * Utility methods for Pack200.
    034 *
    035 * @ThreadSafe
    036 * @since 1.3
    037 */
    038public class Pack200Utils {
    039    private Pack200Utils() { }
    040
    041    /**
    042     * Normalizes a JAR archive in-place so it can be safely signed
    043     * and packed.
    044     *
    045     * <p>As stated in <a
    046     * href="http://download.oracle.com/javase/1.5.0/docs/api/java/util/jar/Pack200.Packer.html">Pack200.Packer's</a>
    047     * javadocs applying a Pack200 compression to a JAR archive will
    048     * in general make its sigantures invalid.  In order to prepare a
    049     * JAR for signing it should be "normalized" by packing and
    050     * unpacking it.  This is what this method does.</p>
    051     *
    052     * <p>Note this methods implicitly sets the segment length to
    053     * -1.</p>
    054     *
    055     * @param jar the JAR archive to normalize
    056     * @throws IOException if reading or writing fails
    057     */
    058    public static void normalize(final File jar)
    059        throws IOException {
    060        normalize(jar, jar, null);
    061    }
    062
    063    /**
    064     * Normalizes a JAR archive in-place so it can be safely signed
    065     * and packed.
    066     *
    067     * <p>As stated in <a
    068     * href="http://download.oracle.com/javase/1.5.0/docs/api/java/util/jar/Pack200.Packer.html">Pack200.Packer's</a>
    069     * javadocs applying a Pack200 compression to a JAR archive will
    070     * in general make its sigantures invalid.  In order to prepare a
    071     * JAR for signing it should be "normalized" by packing and
    072     * unpacking it.  This is what this method does.</p>
    073     *
    074     * @param jar the JAR archive to normalize
    075     * @param props properties to set for the pack operation.  This
    076     * method will implicitly set the segment limit to -1.
    077     * @throws IOException if reading or writing fails
    078     */
    079    public static void normalize(final File jar, final Map<String, String> props)
    080        throws IOException {
    081        normalize(jar, jar, props);
    082    }
    083
    084    /**
    085     * Normalizes a JAR archive so it can be safely signed and packed.
    086     *
    087     * <p>As stated in <a
    088     * href="http://download.oracle.com/javase/1.5.0/docs/api/java/util/jar/Pack200.Packer.html">Pack200.Packer's</a>
    089     * javadocs applying a Pack200 compression to a JAR archive will
    090     * in general make its sigantures invalid.  In order to prepare a
    091     * JAR for signing it should be "normalized" by packing and
    092     * unpacking it.  This is what this method does.</p>
    093     *
    094     * <p>This method does not replace the existing archive but creates
    095     * a new one.</p>
    096     *
    097     * <p>Note this methods implicitly sets the segment length to
    098     * -1.</p>
    099     *
    100     * @param from the JAR archive to normalize
    101     * @param to the normalized archive
    102     * @throws IOException if reading or writing fails
    103     */
    104    public static void normalize(final File from, final File to)
    105        throws IOException {
    106        normalize(from, to, null);
    107    }
    108
    109    /**
    110     * Normalizes a JAR archive so it can be safely signed and packed.
    111     *
    112     * <p>As stated in <a
    113     * href="http://download.oracle.com/javase/1.5.0/docs/api/java/util/jar/Pack200.Packer.html">Pack200.Packer's</a>
    114     * javadocs applying a Pack200 compression to a JAR archive will
    115     * in general make its sigantures invalid.  In order to prepare a
    116     * JAR for signing it should be "normalized" by packing and
    117     * unpacking it.  This is what this method does.</p>
    118     *
    119     * <p>This method does not replace the existing archive but creates
    120     * a new one.</p>
    121     *
    122     * @param from the JAR archive to normalize
    123     * @param to the normalized archive
    124     * @param props properties to set for the pack operation.  This
    125     * method will implicitly set the segment limit to -1.
    126     * @throws IOException if reading or writing fails
    127     */
    128    public static void normalize(final File from, final File to, Map<String, String> props)
    129        throws IOException {
    130        if (props == null) {
    131            props = new HashMap<String, String>();
    132        }
    133        props.put(Pack200.Packer.SEGMENT_LIMIT, "-1");
    134        final File f = File.createTempFile("commons-compress", "pack200normalize");
    135        f.deleteOnExit();
    136        try {
    137            OutputStream os = new FileOutputStream(f);
    138            JarFile j = null;
    139            try {
    140                final Pack200.Packer p = Pack200.newPacker();
    141                p.properties().putAll(props);
    142                p.pack(j = new JarFile(from), os);
    143                j = null;
    144                os.close();
    145                os = null;
    146
    147                final Pack200.Unpacker u = Pack200.newUnpacker();
    148                os = new JarOutputStream(new FileOutputStream(to));
    149                u.unpack(f, (JarOutputStream) os);
    150            } finally {
    151                if (j != null) {
    152                    j.close();
    153                }
    154                if (os != null) {
    155                    os.close();
    156                }
    157            }
    158        } finally {
    159            f.delete();
    160        }
    161    }
    162}