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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;

final class Lz4Constants {
    /**
     * Magic number of LZ4 block.
     */
    static final long MAGIC_NUMBER = (long) 'L' << 56 |
                                     (long) 'Z' << 48 |
                                     (long) '4' << 40 |
                                     (long) 'B' << 32 |
                                            'l' << 24 |
                                            'o' << 16 |
                                            'c' << 8  |
                                            'k';

    /**
     * Full length of LZ4 block header.
     */
    static final int HEADER_LENGTH = 8 +  // magic number
                                     1 +  // token
                                     4 +  // compressed length
                                     4 +  // decompressed length
                                     4;   // checksum

    /**
     * Offsets of header's parts.
     */
    static final int TOKEN_OFFSET = 8;

    static final int COMPRESSED_LENGTH_OFFSET = TOKEN_OFFSET + 1;
    static final int DECOMPRESSED_LENGTH_OFFSET = COMPRESSED_LENGTH_OFFSET + 4;
    static final int CHECKSUM_OFFSET = DECOMPRESSED_LENGTH_OFFSET + 4;

    /**
     * Base value for compression level.
     */
    static final int COMPRESSION_LEVEL_BASE = 10;

    /**
     * LZ4 block sizes.
     */
    static final int MIN_BLOCK_SIZE = 64;
    static final int MAX_BLOCK_SIZE = 1 << COMPRESSION_LEVEL_BASE + 0x0F;   //  32 M
    static final int DEFAULT_BLOCK_SIZE = 1 << 16;  // 64 KB

    /**
     * LZ4 block types.
     */
    static final int BLOCK_TYPE_NON_COMPRESSED = 0x10;
    static final int BLOCK_TYPE_COMPRESSED = 0x20;

    /**
     * Default seed value for xxhash.
     */
    static final int DEFAULT_SEED = 0x9747b28c;

    private Lz4Constants() { }
}