    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.IOException;
    024import java.io.OutputStream;
    025import java.nio.file.Files;
    026import java.nio.file.Path;
    027import java.util.HashMap;
    028import java.util.Map;
    029import java.util.jar.JarFile;
    030import java.util.jar.JarOutputStream;
    031
    032import org.apache.commons.compress.java.util.jar.Pack200;
    033
    034/**
    035 * Utility methods for Pack200.
    036 *
    037 * @ThreadSafe
    038 * @since 1.3
    039 */
    040public class Pack200Utils {
    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="https://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 signatures 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, so it can be safely signed and packed.
    065     *
    066     * <p>As stated in <a
    067     * href="https://download.oracle.com/javase/1.5.0/docs/api/java/util/jar/Pack200.Packer.html">Pack200.Packer's</a>
    068     * javadocs applying a Pack200 compression to a JAR archive will
    069     * in general make its signatures invalid.  In order to prepare a
    070     * JAR for signing it should be "normalized" by packing and
    071     * unpacking it.  This is what this method does.</p>
    072     *
    073     * <p>This method does not replace the existing archive but creates
    074     * a new one.</p>
    075     *
    076     * <p>Note this methods implicitly sets the segment length to
    077     * -1.</p>
    078     *
    079     * @param from the JAR archive to normalize
    080     * @param to the normalized archive
    081     * @throws IOException if reading or writing fails
    082     */
    083    public static void normalize(final File from, final File to)
    084        throws IOException {
    085        normalize(from, to, null);
    086    }
    087
    088    /**
    089     * Normalizes a JAR archive, so it can be safely signed and packed.
    090     *
    091     * <p>As stated in <a
    092     * href="https://download.oracle.com/javase/1.5.0/docs/api/java/util/jar/Pack200.Packer.html">Pack200.Packer's</a>
    093     * javadocs applying a Pack200 compression to a JAR archive will
    094     * in general make its signatures invalid.  In order to prepare a
    095     * JAR for signing it should be "normalized" by packing and
    096     * unpacking it.  This is what this method does.</p>
    097     *
    098     * <p>This method does not replace the existing archive but creates
    099     * a new one.</p>
    100     *
    101     * @param from the JAR archive to normalize
    102     * @param to the normalized archive
    103     * @param props properties to set for the pack operation.  This
    104     * method will implicitly set the segment limit to -1.
    105     * @throws IOException if reading or writing fails
    106     */
    107    public static void normalize(final File from, final File to, Map<String, String> props)
    108            throws IOException {
    109        if (props == null) {
    110            props = new HashMap<>();
    111        }
    112        props.put(Pack200.Packer.SEGMENT_LIMIT, "-1");
    113        final Path tempFile = Files.createTempFile("commons-compress", "pack200normalize");
    114        try {
    115            try (OutputStream fos = Files.newOutputStream(tempFile);
    116                 JarFile jarFile = new JarFile(from)) {
    117                final Pack200.Packer packer = Pack200.newPacker();
    118                packer.properties().putAll(props);
    119                packer.pack(jarFile, fos);
    120            }
    121            final Pack200.Unpacker unpacker = Pack200.newUnpacker();
    122            try (JarOutputStream jos = new JarOutputStream(Files.newOutputStream(to.toPath()))) {
    123                unpacker.unpack(tempFile.toFile(), jos);
    124            }
    125        } finally {
    126            Files.delete(tempFile);
    127        }
    128    }
    129
    130    /**
    131     * Normalizes a JAR archive in-place, so it can be safely signed
    132     * and packed.
    133     *
    134     * <p>As stated in <a
    135     * href="https://download.oracle.com/javase/1.5.0/docs/api/java/util/jar/Pack200.Packer.html">Pack200.Packer's</a>
    136     * javadocs applying a Pack200 compression to a JAR archive will
    137     * in general make its signatures invalid.  In order to prepare a
    138     * JAR for signing it should be "normalized" by packing and
    139     * unpacking it.  This is what this method does.</p>
    140     *
    141     * @param jar the JAR archive to normalize
    142     * @param props properties to set for the pack operation.  This
    143     * method will implicitly set the segment limit to -1.
    144     * @throws IOException if reading or writing fails
    145     */
    146    public static void normalize(final File jar, final Map<String, String> props)
    147        throws IOException {
    148        normalize(jar, jar, props);
    149    }
    150
    151    private Pack200Utils() { }
    152}