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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;

/**
 * Constants for both the {@link Bzip2Encoder} and the {@link Bzip2Decoder}.
 */
final class Bzip2Constants {

    /**
     * Magic number of Bzip2 stream.
     */
    static final int MAGIC_NUMBER = 'B' << 16 | 'Z' << 8 | 'h';

    /**
     * Block header magic number. Equals to BCD (pi).
     */
    static final int BLOCK_HEADER_MAGIC_1 = 0x314159;
    static final int BLOCK_HEADER_MAGIC_2 = 0x265359;

    /**
     * End of stream magic number. Equals to BCD sqrt(pi).
     */
    static final int END_OF_STREAM_MAGIC_1 = 0x177245;
    static final int END_OF_STREAM_MAGIC_2 = 0x385090;

    /**
     * Base block size.
     */
    static final int BASE_BLOCK_SIZE = 100000;

    /**
     * Minimum and maximum size of one block.
     * Must be multiplied by {@link Bzip2Constants#BASE_BLOCK_SIZE}.
     */
    static final int MIN_BLOCK_SIZE = 1;
    static final int MAX_BLOCK_SIZE = 9;

    static final int MAX_BLOCK_LENGTH = MAX_BLOCK_SIZE * BASE_BLOCK_SIZE;

    /**
     * Maximum possible Huffman alphabet size.
     */
    static final int HUFFMAN_MAX_ALPHABET_SIZE = 258;

    /**
     * The longest Huffman code length created by the encoder.
     */
    static final int HUFFMAN_ENCODE_MAX_CODE_LENGTH = 20;

    /**
     * The longest Huffman code length accepted by the decoder.
     */
    static final int HUFFMAN_DECODE_MAX_CODE_LENGTH = 23;

    /**
     * Huffman symbols used for run-length encoding.
     */
    static final int HUFFMAN_SYMBOL_RUNA = 0;
    static final int HUFFMAN_SYMBOL_RUNB = 1;

    /**
     * Huffman symbols range size for Huffman used map.
     */
    static final int HUFFMAN_SYMBOL_RANGE_SIZE = 16;

    /**
     * Maximum length of zero-terminated bit runs of MTF'ed Huffman table.
     */
    static final int HUFFMAN_SELECTOR_LIST_MAX_LENGTH = 6;

    /**
     * Number of symbols decoded after which a new Huffman table is selected.
     */
    static final int HUFFMAN_GROUP_RUN_LENGTH = 50;

    /**
     * Maximum possible number of Huffman table selectors.
     */
    static final int MAX_SELECTORS = 2 + 900000 / HUFFMAN_GROUP_RUN_LENGTH; // 18002

    /**
     * Minimum number of alternative Huffman tables.
     */
    static final int HUFFMAN_MINIMUM_TABLES = 2;

    /**
     * Maximum number of alternative Huffman tables.
     */
    static final int HUFFMAN_MAXIMUM_TABLES = 6;

    private Bzip2Constants() { }
}