1 /*

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

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

     4  *

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

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

     7  * published by the Free Software Foundation.  Oracle designates this

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

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

    10  *

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

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

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

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

    15  * accompanied this code).

    16  *

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

    18  * 2 along with this work; if not, write to the Free Software Foundation,

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

    20  *

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

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

    23  * questions.

    24  */

    25 package jdk.internal.jimage.decompressor;

    26 

    27 import java.io.ByteArrayOutputStream;

    28 import java.io.IOException;

    29 import java.util.zip.DataFormatException;

    30 import java.util.zip.Inflater;

    31 

    32 /**

    33  *

    34  * ZIP Decompressor

    35  */

    36 final class ZipDecompressor implements ResourceDecompressor {

    37 

    38     @Override

    39     public String getName() {

    40         return ZipDecompressorFactory.NAME;

    41     }

    42 

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

    44         Inflater inflater = new Inflater();

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

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

    47         byte[] buffer = new byte[1024];

    48 

    49         while (!inflater.finished()) {

    50             int count;

    51 

    52             try {

    53                 count = inflater.inflate(buffer);

    54             } catch (DataFormatException ex) {

    55                 return null;

    56             }

    57 

    58             stream.write(buffer, 0, count);

    59         }

    60 

    61         try {

    62             stream.close();

    63         } catch (IOException ex) {

    64             return null;

    65         }

    66 

    67         byte[] bytesOut = stream.toByteArray();

    68         inflater.end();

    69 

    70         return bytesOut;

    71     }

    72 

    73     @Override

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

    75             int originalSize) throws Exception {

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

    77         return decompressed;

    78     }

    79 }