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1 | /*
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2 | * CRC32Hash
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3 | *
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4 | * Authors: Lasse Collin <lasse.collin@tukaani.org>
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5 | * Igor Pavlov <http://7-zip.org/>
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6 | *
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7 | * This file has been put into the public domain.
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8 | * You can do whatever you want with this file.
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9 | */
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10 |
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11 | package org.tukaani.xz.lz;
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12 |
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13 | /**
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14 | * Provides a CRC32 table using the polynomial from IEEE 802.3.
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15 | */
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16 | class CRC32Hash {
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17 | private static final int CRC32_POLY = 0xEDB88320;
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18 |
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19 | static final int[] crcTable = new int[256];
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20 |
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21 | static {
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22 | for (int i = 0; i < 256; ++i) {
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23 | int r = i;
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24 |
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25 | for (int j = 0; j < 8; ++j) {
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26 | if ((r & 1) != 0)
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27 | r = (r >>> 1) ^ CRC32_POLY;
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28 | else
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29 | r >>>= 1;
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30 | }
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31 |
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32 | crcTable[i] = r;
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33 | }
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34 | }
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35 | }
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