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This artifact provides a single jar that contains all classes required to use remote Jakarta Enterprise Beans and Jakarta Messaging, including all dependencies. It is intended for use by those not using maven, maven users should just import the Jakarta Enterprise Beans and Jakarta Messaging BOM's instead (shaded JAR's cause lots of problems with maven, as it is very easy to inadvertently end up with different versions on classes on the class path).

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/*
 * Copyright (C) 2011 The Guava Authors
 *
 * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except
 * in compliance with the License. You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software distributed under the License
 * is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express
 * or implied. See the License for the specific language governing permissions and limitations under
 * the License.
 */

package com.google.common.hash;

import com.google.errorprone.annotations.Immutable;

/**
 * This class generates a CRC32C checksum, defined by RFC 3720, Section 12.1. The generator
 * polynomial for this checksum is {@code 0x11EDC6F41}.
 *
 * @author Kurt Alfred Kluever
 */
@Immutable
final class Crc32cHashFunction extends AbstractHashFunction {
  static final HashFunction CRC_32_C = new Crc32cHashFunction();

  @Override
  public int bits() {
    return 32;
  }

  @Override
  public Hasher newHasher() {
    return new Crc32cHasher();
  }

  @Override
  public String toString() {
    return "Hashing.crc32c()";
  }

  static final class Crc32cHasher extends AbstractByteHasher {

    // The CRC table, generated from the polynomial 0x11EDC6F41.
    static final int[] CRC_TABLE = {
      0x00000000, 0xf26b8303, 0xe13b70f7, 0x1350f3f4,
      0xc79a971f, 0x35f1141c, 0x26a1e7e8, 0xd4ca64eb,
      0x8ad958cf, 0x78b2dbcc, 0x6be22838, 0x9989ab3b,
      0x4d43cfd0, 0xbf284cd3, 0xac78bf27, 0x5e133c24,
      0x105ec76f, 0xe235446c, 0xf165b798, 0x030e349b,
      0xd7c45070, 0x25afd373, 0x36ff2087, 0xc494a384,
      0x9a879fa0, 0x68ec1ca3, 0x7bbcef57, 0x89d76c54,
      0x5d1d08bf, 0xaf768bbc, 0xbc267848, 0x4e4dfb4b,
      0x20bd8ede, 0xd2d60ddd, 0xc186fe29, 0x33ed7d2a,
      0xe72719c1, 0x154c9ac2, 0x061c6936, 0xf477ea35,
      0xaa64d611, 0x580f5512, 0x4b5fa6e6, 0xb93425e5,
      0x6dfe410e, 0x9f95c20d, 0x8cc531f9, 0x7eaeb2fa,
      0x30e349b1, 0xc288cab2, 0xd1d83946, 0x23b3ba45,
      0xf779deae, 0x05125dad, 0x1642ae59, 0xe4292d5a,
      0xba3a117e, 0x4851927d, 0x5b016189, 0xa96ae28a,
      0x7da08661, 0x8fcb0562, 0x9c9bf696, 0x6ef07595,
      0x417b1dbc, 0xb3109ebf, 0xa0406d4b, 0x522bee48,
      0x86e18aa3, 0x748a09a0, 0x67dafa54, 0x95b17957,
      0xcba24573, 0x39c9c670, 0x2a993584, 0xd8f2b687,
      0x0c38d26c, 0xfe53516f, 0xed03a29b, 0x1f682198,
      0x5125dad3, 0xa34e59d0, 0xb01eaa24, 0x42752927,
      0x96bf4dcc, 0x64d4cecf, 0x77843d3b, 0x85efbe38,
      0xdbfc821c, 0x2997011f, 0x3ac7f2eb, 0xc8ac71e8,
      0x1c661503, 0xee0d9600, 0xfd5d65f4, 0x0f36e6f7,
      0x61c69362, 0x93ad1061, 0x80fde395, 0x72966096,
      0xa65c047d, 0x5437877e, 0x4767748a, 0xb50cf789,
      0xeb1fcbad, 0x197448ae, 0x0a24bb5a, 0xf84f3859,
      0x2c855cb2, 0xdeeedfb1, 0xcdbe2c45, 0x3fd5af46,
      0x7198540d, 0x83f3d70e, 0x90a324fa, 0x62c8a7f9,
      0xb602c312, 0x44694011, 0x5739b3e5, 0xa55230e6,
      0xfb410cc2, 0x092a8fc1, 0x1a7a7c35, 0xe811ff36,
      0x3cdb9bdd, 0xceb018de, 0xdde0eb2a, 0x2f8b6829,
      0x82f63b78, 0x709db87b, 0x63cd4b8f, 0x91a6c88c,
      0x456cac67, 0xb7072f64, 0xa457dc90, 0x563c5f93,
      0x082f63b7, 0xfa44e0b4, 0xe9141340, 0x1b7f9043,
      0xcfb5f4a8, 0x3dde77ab, 0x2e8e845f, 0xdce5075c,
      0x92a8fc17, 0x60c37f14, 0x73938ce0, 0x81f80fe3,
      0x55326b08, 0xa759e80b, 0xb4091bff, 0x466298fc,
      0x1871a4d8, 0xea1a27db, 0xf94ad42f, 0x0b21572c,
      0xdfeb33c7, 0x2d80b0c4, 0x3ed04330, 0xccbbc033,
      0xa24bb5a6, 0x502036a5, 0x4370c551, 0xb11b4652,
      0x65d122b9, 0x97baa1ba, 0x84ea524e, 0x7681d14d,
      0x2892ed69, 0xdaf96e6a, 0xc9a99d9e, 0x3bc21e9d,
      0xef087a76, 0x1d63f975, 0x0e330a81, 0xfc588982,
      0xb21572c9, 0x407ef1ca, 0x532e023e, 0xa145813d,
      0x758fe5d6, 0x87e466d5, 0x94b49521, 0x66df1622,
      0x38cc2a06, 0xcaa7a905, 0xd9f75af1, 0x2b9cd9f2,
      0xff56bd19, 0x0d3d3e1a, 0x1e6dcdee, 0xec064eed,
      0xc38d26c4, 0x31e6a5c7, 0x22b65633, 0xd0ddd530,
      0x0417b1db, 0xf67c32d8, 0xe52cc12c, 0x1747422f,
      0x49547e0b, 0xbb3ffd08, 0xa86f0efc, 0x5a048dff,
      0x8ecee914, 0x7ca56a17, 0x6ff599e3, 0x9d9e1ae0,
      0xd3d3e1ab, 0x21b862a8, 0x32e8915c, 0xc083125f,
      0x144976b4, 0xe622f5b7, 0xf5720643, 0x07198540,
      0x590ab964, 0xab613a67, 0xb831c993, 0x4a5a4a90,
      0x9e902e7b, 0x6cfbad78, 0x7fab5e8c, 0x8dc0dd8f,
      0xe330a81a, 0x115b2b19, 0x020bd8ed, 0xf0605bee,
      0x24aa3f05, 0xd6c1bc06, 0xc5914ff2, 0x37faccf1,
      0x69e9f0d5, 0x9b8273d6, 0x88d28022, 0x7ab90321,
      0xae7367ca, 0x5c18e4c9, 0x4f48173d, 0xbd23943e,
      0xf36e6f75, 0x0105ec76, 0x12551f82, 0xe03e9c81,
      0x34f4f86a, 0xc69f7b69, 0xd5cf889d, 0x27a40b9e,
      0x79b737ba, 0x8bdcb4b9, 0x988c474d, 0x6ae7c44e,
      0xbe2da0a5, 0x4c4623a6, 0x5f16d052, 0xad7d5351
    };

    private int crc = 0;

    @Override
    public void update(byte b) {
      crc ^= 0xFFFFFFFF;
      // See Hacker's Delight 2nd Edition, Figure 14-7.
      crc = ~((crc >>> 8) ^ CRC_TABLE[(crc ^ b) & 0xFF]);
    }

    @Override
    public HashCode hash() {
      return HashCode.fromInt(crc);
    }
  }
}