/*

 * Copyright (c) 2015, 2016, Oracle and/or its affiliates. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.  Oracle designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Oracle in the LICENSE file that accompanied this code.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

 * or visit www.oracle.com if you need additional information or have any

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 */

package jdk.internal.jimage.decompressor;

import java.io.ByteArrayOutputStream;

import java.util.zip.Inflater;

/**

 *

 * ZIP Decompressor

 *

 * @implNote This class needs to maintain JDK 8 source compatibility.

 *

 * It is used internally in the JDK to implement jimage/jrtfs access,

 * but also compiled and delivered as part of the jrtfs.jar to support access

 * to the jimage file provided by the shipped JDK by tools running on JDK 8.

 */

final class ZipDecompressor implements ResourceDecompressor {

    @Override

    public String getName() {

        return ZipDecompressorFactory.NAME;

    }

    static byte[] decompress(byte[] bytesIn, int offset) throws Exception {

        Inflater inflater = new Inflater();

        inflater.setInput(bytesIn, offset, bytesIn.length - offset);

        ByteArrayOutputStream stream = new ByteArrayOutputStream(bytesIn.length - offset);

        byte[] buffer = new byte[1024];

        while (!inflater.finished()) {

            int count = inflater.inflate(buffer);

            stream.write(buffer, 0, count);

        }

        stream.close();

        byte[] bytesOut = stream.toByteArray();

        inflater.end();

        return bytesOut;

    }

    @Override

    public byte[] decompress(StringsProvider reader, byte[] content, int offset,

            long originalSize) throws Exception {

        byte[] decompressed = decompress(content, offset);

        return decompressed;

    }

}