    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 *   https://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 and packed.
    043     *
    044     * <p>
    045     * As stated in <a href="https://download.oracle.com/javase/1.5.0/docs/api/java/util/jar/Pack200.Packer.html">Pack200.Packer's</a> javadocs applying a
    046     * Pack200 compression to a JAR archive will in general make its signatures invalid. In order to prepare a JAR for signing it should be "normalized" by
    047     * packing and unpacking it. This is what this method does.
    048     * </p>
    049     *
    050     * <p>
    051     * Note this methods implicitly sets the segment length to -1.
    052     * </p>
    053     *
    054     * @param jar the JAR archive to normalize
    055     * @throws IOException if reading or writing fails
    056     */
    057    public static void normalize(final File jar) throws IOException {
    058        normalize(jar, jar, null);
    059    }
    060
    061    /**
    062     * Normalizes a JAR archive, so it can be safely signed and packed.
    063     *
    064     * <p>
    065     * As stated in <a href="https://download.oracle.com/javase/1.5.0/docs/api/java/util/jar/Pack200.Packer.html">Pack200.Packer's</a> javadocs applying a
    066     * Pack200 compression to a JAR archive will in general make its signatures invalid. In order to prepare a JAR for signing it should be "normalized" by
    067     * packing and unpacking it. This is what this method does.
    068     * </p>
    069     *
    070     * <p>
    071     * This method does not replace the existing archive but creates a new one.
    072     * </p>
    073     *
    074     * <p>
    075     * Note this methods implicitly sets the segment length to -1.
    076     * </p>
    077     *
    078     * @param from the JAR archive to normalize
    079     * @param to   the normalized archive
    080     * @throws IOException if reading or writing fails
    081     */
    082    public static void normalize(final File from, final File to) throws IOException {
    083        normalize(from, to, null);
    084    }
    085
    086    /**
    087     * Normalizes a JAR archive, so it can be safely signed and packed.
    088     *
    089     * <p>
    090     * As stated in <a href="https://download.oracle.com/javase/1.5.0/docs/api/java/util/jar/Pack200.Packer.html">Pack200.Packer's</a> javadocs applying a
    091     * Pack200 compression to a JAR archive will in general make its signatures invalid. In order to prepare a JAR for signing it should be "normalized" by
    092     * packing and unpacking it. This is what this method does.
    093     * </p>
    094     *
    095     * <p>
    096     * This method does not replace the existing archive but creates a new one.
    097     * </p>
    098     *
    099     * @param from  the JAR archive to normalize
    100     * @param to    the normalized archive
    101     * @param props properties to set for the pack operation. This method will implicitly set the segment limit to -1.
    102     * @throws IOException if reading or writing fails
    103     */
    104    public static void normalize(final File from, final File to, Map<String, String> props) throws IOException {
    105        if (props == null) {
    106            props = new HashMap<>();
    107        }
    108        props.put(Pack200.Packer.SEGMENT_LIMIT, "-1");
    109        final Path tempFile = Files.createTempFile("commons-compress", "pack200normalize");
    110        try {
    111            try (OutputStream fos = Files.newOutputStream(tempFile);
    112                    JarFile jarFile = new JarFile(from)) {
    113                final Pack200.Packer packer = Pack200.newPacker();
    114                packer.properties().putAll(props);
    115                packer.pack(jarFile, fos);
    116            }
    117            final Pack200.Unpacker unpacker = Pack200.newUnpacker();
    118            try (JarOutputStream jos = new JarOutputStream(Files.newOutputStream(to.toPath()))) {
    119                unpacker.unpack(tempFile.toFile(), jos);
    120            }
    121        } finally {
    122            Files.delete(tempFile);
    123        }
    124    }
    125
    126    /**
    127     * Normalizes a JAR archive in-place, so it can be safely signed and packed.
    128     *
    129     * <p>
    130     * As stated in <a href="https://download.oracle.com/javase/1.5.0/docs/api/java/util/jar/Pack200.Packer.html">Pack200.Packer's</a> javadocs applying a
    131     * Pack200 compression to a JAR archive will in general make its signatures invalid. In order to prepare a JAR for signing it should be "normalized" by
    132     * packing and unpacking it. This is what this method does.
    133     * </p>
    134     *
    135     * @param jar   the JAR archive to normalize
    136     * @param props properties to set for the pack operation. This method will implicitly set the segment limit to -1.
    137     * @throws IOException if reading or writing fails
    138     */
    139    public static void normalize(final File jar, final Map<String, String> props) throws IOException {
    140        normalize(jar, jar, props);
    141    }
    142
    143    private Pack200Utils() {
    144    }
    145}