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 */
019package org.apache.commons.compress.archivers.jar;
020
021import java.io.IOException;
022import java.io.OutputStream;
023
024import org.apache.commons.compress.archivers.zip.JarMarker;
025import org.apache.commons.compress.archivers.zip.ZipArchiveEntry;
026import org.apache.commons.compress.archivers.zip.ZipArchiveOutputStream;
027
028/**
029 * Subclass that adds a special extra field to the very first entry which allows the created archive to be used as an executable jar on Solaris.
030 *
031 * @NotThreadSafe
032 */
033public class JarArchiveOutputStream extends ZipArchiveOutputStream {
034
035    private boolean jarMarkerAdded;
036
037    public JarArchiveOutputStream(final OutputStream out) {
038        super(out);
039    }
040
041    /**
042     * Constructs a new instance that wraps the output stream using the provided encoding.
043     *
044     * @param out      the output stream to wrap
045     * @param encoding the encoding to use. Use null for the platform default.
046     * @since 1.10
047     */
048    public JarArchiveOutputStream(final OutputStream out, final String encoding) {
049        super(out);
050        setEncoding(encoding);
051    }
052
053    // @throws ClassCastException if entry is not an instance of ZipArchiveEntry
054    @Override
055    public void putArchiveEntry(final ZipArchiveEntry entry) throws IOException {
056        if (!jarMarkerAdded) {
057            entry.addAsFirstExtraField(JarMarker.getInstance());
058            jarMarkerAdded = true;
059        }
060        super.putArchiveEntry(entry);
061    }
062}