org.apache.commons.compress.archivers.Lister Maven / Gradle / Ivy

/*
 *  Licensed to the Apache Software Foundation (ASF) under one or more
 *  contributor license agreements.  See the NOTICE file distributed with
 *  this work for additional information regarding copyright ownership.
 *  The ASF licenses this file to You under the Apache License, Version 2.0
 *  (the "License"); you may not use this file except in compliance with
 *  the License.  You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 *  Unless required by applicable law or agreed to in writing, software
 *  distributed under the License is distributed on an "AS IS" BASIS,
 *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *  See the License for the specific language governing permissions and
 *  limitations under the License.
 *
 */

package org.apache.commons.compress.archivers;

import java.io.BufferedInputStream;
import java.io.File;
import java.io.InputStream;
import java.nio.file.Files;

/**
 * Simple command line application that lists the contents of an archive.
 *
 * The name of the archive must be given as a command line argument.
 * The optional second argument defines the archive type, in case the format is not recognized.
 *
 * @since 1.1
 */
public final class Lister {
    private static final ArchiveStreamFactory factory = new ArchiveStreamFactory();

    public static void main(final String[] args) throws Exception {
        if (args.length == 0) {
            usage();
            return;
        }
        System.out.println("Analysing " + args[0]);
        final File f = new File(args[0]);
        if (!f.isFile()) {
            System.err.println(f + " doesn't exist or is a directory");
        }
        try (final InputStream fis = new BufferedInputStream(Files.newInputStream(f.toPath()));
                final ArchiveInputStream ais = createArchiveInputStream(args, fis)) {
            System.out.println("Created " + ais.toString());
            ArchiveEntry ae;
            while ((ae = ais.getNextEntry()) != null) {
                System.out.println(ae.getName());
            }
        }
    }

    private static ArchiveInputStream createArchiveInputStream(final String[] args, final InputStream fis)
            throws ArchiveException {
        if (args.length > 1) {
            return factory.createArchiveInputStream(args[1], fis);
        }
        return factory.createArchiveInputStream(fis);
    }

    private static void usage() {
        System.out.println("Parameters: archive-name [archive-type]");
    }

}