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This artifact provides a single jar that contains all classes required to use remote EJB and JMS, including all dependencies. It is intended for use by those not using maven, maven users should just import the EJB and JMS 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 2014 The Netty Project
 *
 * The Netty Project licenses this file to you 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:
 *
 *   https://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 io.netty.handler.codec.compression;

/**
 * A CRC32 calculator.
 */
final class Crc32 {
    /**
     * A static CRC lookup table.
     */
    private static final int[] crc32Table = {
            0x00000000, 0x04c11db7, 0x09823b6e, 0x0d4326d9,
            0x130476dc, 0x17c56b6b, 0x1a864db2, 0x1e475005,
            0x2608edb8, 0x22c9f00f, 0x2f8ad6d6, 0x2b4bcb61,
            0x350c9b64, 0x31cd86d3, 0x3c8ea00a, 0x384fbdbd,
            0x4c11db70, 0x48d0c6c7, 0x4593e01e, 0x4152fda9,
            0x5f15adac, 0x5bd4b01b, 0x569796c2, 0x52568b75,
            0x6a1936c8, 0x6ed82b7f, 0x639b0da6, 0x675a1011,
            0x791d4014, 0x7ddc5da3, 0x709f7b7a, 0x745e66cd,
            0x9823b6e0, 0x9ce2ab57, 0x91a18d8e, 0x95609039,
            0x8b27c03c, 0x8fe6dd8b, 0x82a5fb52, 0x8664e6e5,
            0xbe2b5b58, 0xbaea46ef, 0xb7a96036, 0xb3687d81,
            0xad2f2d84, 0xa9ee3033, 0xa4ad16ea, 0xa06c0b5d,
            0xd4326d90, 0xd0f37027, 0xddb056fe, 0xd9714b49,
            0xc7361b4c, 0xc3f706fb, 0xceb42022, 0xca753d95,
            0xf23a8028, 0xf6fb9d9f, 0xfbb8bb46, 0xff79a6f1,
            0xe13ef6f4, 0xe5ffeb43, 0xe8bccd9a, 0xec7dd02d,
            0x34867077, 0x30476dc0, 0x3d044b19, 0x39c556ae,
            0x278206ab, 0x23431b1c, 0x2e003dc5, 0x2ac12072,
            0x128e9dcf, 0x164f8078, 0x1b0ca6a1, 0x1fcdbb16,
            0x018aeb13, 0x054bf6a4, 0x0808d07d, 0x0cc9cdca,
            0x7897ab07, 0x7c56b6b0, 0x71159069, 0x75d48dde,
            0x6b93dddb, 0x6f52c06c, 0x6211e6b5, 0x66d0fb02,
            0x5e9f46bf, 0x5a5e5b08, 0x571d7dd1, 0x53dc6066,
            0x4d9b3063, 0x495a2dd4, 0x44190b0d, 0x40d816ba,
            0xaca5c697, 0xa864db20, 0xa527fdf9, 0xa1e6e04e,
            0xbfa1b04b, 0xbb60adfc, 0xb6238b25, 0xb2e29692,
            0x8aad2b2f, 0x8e6c3698, 0x832f1041, 0x87ee0df6,
            0x99a95df3, 0x9d684044, 0x902b669d, 0x94ea7b2a,
            0xe0b41de7, 0xe4750050, 0xe9362689, 0xedf73b3e,
            0xf3b06b3b, 0xf771768c, 0xfa325055, 0xfef34de2,
            0xc6bcf05f, 0xc27dede8, 0xcf3ecb31, 0xcbffd686,
            0xd5b88683, 0xd1799b34, 0xdc3abded, 0xd8fba05a,
            0x690ce0ee, 0x6dcdfd59, 0x608edb80, 0x644fc637,
            0x7a089632, 0x7ec98b85, 0x738aad5c, 0x774bb0eb,
            0x4f040d56, 0x4bc510e1, 0x46863638, 0x42472b8f,
            0x5c007b8a, 0x58c1663d, 0x558240e4, 0x51435d53,
            0x251d3b9e, 0x21dc2629, 0x2c9f00f0, 0x285e1d47,
            0x36194d42, 0x32d850f5, 0x3f9b762c, 0x3b5a6b9b,
            0x0315d626, 0x07d4cb91, 0x0a97ed48, 0x0e56f0ff,
            0x1011a0fa, 0x14d0bd4d, 0x19939b94, 0x1d528623,
            0xf12f560e, 0xf5ee4bb9, 0xf8ad6d60, 0xfc6c70d7,
            0xe22b20d2, 0xe6ea3d65, 0xeba91bbc, 0xef68060b,
            0xd727bbb6, 0xd3e6a601, 0xdea580d8, 0xda649d6f,
            0xc423cd6a, 0xc0e2d0dd, 0xcda1f604, 0xc960ebb3,
            0xbd3e8d7e, 0xb9ff90c9, 0xb4bcb610, 0xb07daba7,
            0xae3afba2, 0xaafbe615, 0xa7b8c0cc, 0xa379dd7b,
            0x9b3660c6, 0x9ff77d71, 0x92b45ba8, 0x9675461f,
            0x8832161a, 0x8cf30bad, 0x81b02d74, 0x857130c3,
            0x5d8a9099, 0x594b8d2e, 0x5408abf7, 0x50c9b640,
            0x4e8ee645, 0x4a4ffbf2, 0x470cdd2b, 0x43cdc09c,
            0x7b827d21, 0x7f436096, 0x7200464f, 0x76c15bf8,
            0x68860bfd, 0x6c47164a, 0x61043093, 0x65c52d24,
            0x119b4be9, 0x155a565e, 0x18197087, 0x1cd86d30,
            0x029f3d35, 0x065e2082, 0x0b1d065b, 0x0fdc1bec,
            0x3793a651, 0x3352bbe6, 0x3e119d3f, 0x3ad08088,
            0x2497d08d, 0x2056cd3a, 0x2d15ebe3, 0x29d4f654,
            0xc5a92679, 0xc1683bce, 0xcc2b1d17, 0xc8ea00a0,
            0xd6ad50a5, 0xd26c4d12, 0xdf2f6bcb, 0xdbee767c,
            0xe3a1cbc1, 0xe760d676, 0xea23f0af, 0xeee2ed18,
            0xf0a5bd1d, 0xf464a0aa, 0xf9278673, 0xfde69bc4,
            0x89b8fd09, 0x8d79e0be, 0x803ac667, 0x84fbdbd0,
            0x9abc8bd5, 0x9e7d9662, 0x933eb0bb, 0x97ffad0c,
            0xafb010b1, 0xab710d06, 0xa6322bdf, 0xa2f33668,
            0xbcb4666d, 0xb8757bda, 0xb5365d03, 0xb1f740b4
    };

    /**
     * The current CRC.
     */
    private int crc = 0xffffffff;

    /**
     * @return The current CRC.
     */
    public int getCRC() {
        return ~crc;
    }

    /**
     * Update the CRC with a single byte.
     * @param value The value to update the CRC with
     */
    public void updateCRC(final int value) {
        final int crc = this.crc;
        this.crc = crc << 8 ^ crc32Table[(crc >> 24 ^ value) & 0xff];
    }

    /**
     * Update the CRC with a sequence of identical bytes.
     * @param value The value to update the CRC with
     * @param count The number of bytes
     */
    public void updateCRC(final int value, int count) {
        while (count-- > 0) {
            updateCRC(value);
        }
    }
}