    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.InputStream;
    023
    024import org.apache.commons.compress.archivers.zip.ZipArchiveEntry;
    025import org.apache.commons.compress.archivers.zip.ZipArchiveInputStream;
    026
    027/**
    028 * Implements an input stream that can read entries from jar files.
    029 *
    030 * @NotThreadSafe
    031 */
    032public class JarArchiveInputStream extends ZipArchiveInputStream {
    033
    034    /**
    035     * Checks if the signature matches what is expected for a jar file (in this case it is the same as for a ZIP file).
    036     *
    037     * @param signature the bytes to check
    038     * @param length    the number of bytes to check
    039     * @return true, if this stream is a jar archive stream, false otherwise
    040     */
    041    public static boolean matches(final byte[] signature, final int length) {
    042        return ZipArchiveInputStream.matches(signature, length);
    043    }
    044
    045    /**
    046     * Creates an instance from the input stream using the default encoding.
    047     *
    048     * @param inputStream the input stream to wrap
    049     */
    050    public JarArchiveInputStream(final InputStream inputStream) {
    051        super(inputStream);
    052    }
    053
    054    /**
    055     * Creates an instance from the input stream using the specified encoding.
    056     *
    057     * @param inputStream the input stream to wrap
    058     * @param encoding    the encoding to use
    059     * @since 1.10
    060     */
    061    public JarArchiveInputStream(final InputStream inputStream, final String encoding) {
    062        super(inputStream, encoding);
    063    }
    064
    065    @Override
    066    public JarArchiveEntry getNextEntry() throws IOException {
    067        return getNextJarEntry();
    068    }
    069
    070    /**
    071     * Gets the next entry.
    072     *
    073     * @return the next entry.
    074     * @throws IOException if an I/O error occurs.
    075     * @deprecated Use {@link #getNextEntry()}.
    076     */
    077    @Deprecated
    078    public JarArchiveEntry getNextJarEntry() throws IOException {
    079        final ZipArchiveEntry entry = getNextZipEntry();
    080        return entry == null ? null : new JarArchiveEntry(entry);
    081    }
    082}