Implemented a Bzip2Encoder
Motivation: Bzip2Encoder provides sending data compressed in bzip2 format. Modifications: Added classes: - Bzip2Encoder - Bzip2BitWriter - Bzip2BlockCompressor - Bzip2DivSufSort - Bzip2HuffmanAllocator - Bzip2HuffmanStageEncoder - Bzip2MTFAndRLE2StageEncoder - Bzip2EncoderTest Modified classes: - Bzip2Constants (splited BLOCK_HEADER_MAGIC and END_OF_STREAM_MAGIC) - Bzip2Decoder (use splited magic numbers) Added integration tests for Bzip2Encoder/Decoder Result: Implemented new encoder which can compress outgoing data in bzip2 format.
This commit is contained in:
Idel Pivnitskiy
Norman Maurer
parent
3c6017a9b1
commit
ed7240b597
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@ -89,6 +89,15 @@ and decompression library written by Matthew J. Francis. It can be obtained at:
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* HOMEPAGE:
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* https://code.google.com/p/jbzip2/
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This product contains a modified portion of 'libdivsufsort', a C API library to construct
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the suffix array and the Burrows-Wheeler transformed string for any input string of
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a constant-size alphabet written by Yuta Mori. It can be obtained at:
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* LICENSE:
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* license/LICENSE.libdivsufsort.txt (MIT License)
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* HOMEPAGE:
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* https://code.google.com/p/libdivsufsort/
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This product optionally depends on 'JZlib', a re-implementation of zlib in
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pure Java, which can be obtained at:
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@ -0,0 +1,109 @@
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/*
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* Copyright 2014 The Netty Project
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*
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* The Netty Project licenses this file to you under the Apache License,
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* version 2.0 (the "License"); you may not use this file except in compliance
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* with the License. You may obtain a copy of the License at:
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
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* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
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* License for the specific language governing permissions and limitations
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* under the License.
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*/
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package io.netty.handler.codec.compression;
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import io.netty.buffer.ByteBuf;
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/**
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* A bit writer that allows the writing of single bit booleans, unary numbers, bit strings
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* of arbitrary length (up to 24 bits), and bit aligned 32-bit integers. A single byte at a
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* time is written to the {@link ByteBuf} when sufficient bits have been accumulated.
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*/
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final class Bzip2BitWriter {
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/**
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* A buffer of bits waiting to be written to the output stream.
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*/
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private int bitBuffer;
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/**
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* The number of bits currently buffered in {@link #bitBuffer}.
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*/
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private int bitCount;
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/**
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* Writes up to 24 bits to the output {@link ByteBuf}.
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* @param count The number of bits to write (maximum {@code 24}, because the {@link #bitBuffer}
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* is {@code int} and it can store up to {@code 8} bits before calling)
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* @param value The bits to write
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*/
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void writeBits(ByteBuf out, final int count, final int value) {
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if (count < 0 || count > 24) {
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throw new IllegalArgumentException("count: " + count + " (expected: 0-24)");
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}
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int bitCount = this.bitCount;
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int bitBuffer = this.bitBuffer | (value << (32 - count)) >>> bitCount;
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bitCount += count;
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while (bitCount >= 8) {
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out.writeByte(bitBuffer >>> 24);
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bitBuffer <<= 8;
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bitCount -= 8;
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}
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this.bitBuffer = bitBuffer;
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this.bitCount = bitCount;
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}
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/**
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* Writes a single bit to the output {@link ByteBuf}.
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* @param value The bit to write
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*/
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void writeBoolean(ByteBuf out, final boolean value) {
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int bitCount = this.bitCount + 1;
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int bitBuffer = this.bitBuffer | (value ? 1 : 0) << (32 - bitCount);
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if (bitCount == 8) {
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out.writeByte(bitBuffer >>> 24);
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bitBuffer = 0;
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bitCount = 0;
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}
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this.bitBuffer = bitBuffer;
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this.bitCount = bitCount;
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}
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/**
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* Writes a zero-terminated unary number to the output {@link ByteBuf}.
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* Example of the output for value = 6: {@code 1111110}
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* @param value The number of {@code 1} to write
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*/
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void writeUnary(ByteBuf out, int value) {
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if (value < 0) {
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throw new IllegalArgumentException("value: " + value + " (expected 0 or more)");
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}
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while (value-- > 0) {
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writeBoolean(out, true);
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}
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writeBoolean(out, false);
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}
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/**
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* Writes an integer as 32 bits to the output {@link ByteBuf}.
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* @param value The integer to write
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*/
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void writeInt(ByteBuf out, final int value) {
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writeBits(out, 16, (value >>> 16) & 0xffff);
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writeBits(out, 16, value & 0xffff);
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}
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/**
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* Writes any remaining bits to the output {@link ByteBuf},
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* zero padding to a whole byte as required.
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*/
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void flush(ByteBuf out) {
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if (bitCount > 0) {
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writeBits(out, 8 - bitCount, 0);
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}
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}
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}
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@ -0,0 +1,294 @@
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/*
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* Copyright 2014 The Netty Project
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*
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* The Netty Project licenses this file to you under the Apache License,
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* version 2.0 (the "License"); you may not use this file except in compliance
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* with the License. You may obtain a copy of the License at:
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
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* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
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* License for the specific language governing permissions and limitations
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* under the License.
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*/
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package io.netty.handler.codec.compression;
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import io.netty.buffer.ByteBuf;
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import static io.netty.handler.codec.compression.Bzip2Constants.*;
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/**
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* Compresses and writes a single Bzip2 block.<br><br>
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*
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* Block encoding consists of the following stages:<br>
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* 1. Run-Length Encoding[1] - {@link #write(int)}<br>
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* 2. Burrows Wheeler Transform - {@link #close(ByteBuf)} (through {@link Bzip2DivSufSort})<br>
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* 3. Write block header - {@link #close(ByteBuf)}<br>
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* 4. Move To Front Transform - {@link #close(ByteBuf)} (through {@link Bzip2HuffmanStageEncoder})<br>
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* 5. Run-Length Encoding[2] - {@link #close(ByteBuf)} (through {@link Bzip2HuffmanStageEncoder})<br>
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* 6. Create and write Huffman tables - {@link #close(ByteBuf)} (through {@link Bzip2HuffmanStageEncoder})<br>
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* 7. Huffman encode and write data - {@link #close(ByteBuf)} (through {@link Bzip2HuffmanStageEncoder})
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*/
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final class Bzip2BlockCompressor {
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/**
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* A writer that provides bit-level writes.
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*/
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private final Bzip2BitWriter writer;
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/**
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* CRC builder for the block.
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*/
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private final Crc32 crc = new Crc32();
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/**
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* The RLE'd block data.
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*/
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private final byte[] block;
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/**
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* Current length of the data within the {@link #block} array.
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*/
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private int blockLength;
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/**
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* A limit beyond which new data will not be accepted into the block.
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*/
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private final int blockLengthLimit;
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/**
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* The values that are present within the RLE'd block data. For each index, {@code true} if that
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* value is present within the data, otherwise {@code false}.
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*/
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private final boolean[] blockValuesPresent = new boolean[256];
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/**
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* The Burrows Wheeler Transformed block data.
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*/
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private final int[] bwtBlock;
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/**
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* The current RLE value being accumulated (undefined when {@link #rleLength} is 0).
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*/
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private int rleCurrentValue = -1;
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/**
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* The repeat count of the current RLE value.
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*/
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private int rleLength;
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/**
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* @param writer The {@link Bzip2BitWriter} which provides bit-level writes
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* @param blockSize The declared block size in bytes. Up to this many bytes will be accepted
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* into the block after Run-Length Encoding is applied
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*/
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Bzip2BlockCompressor(final Bzip2BitWriter writer, final int blockSize) {
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this.writer = writer;
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// One extra byte is added to allow for the block wrap applied in close()
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block = new byte[blockSize + 1];
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bwtBlock = new int[blockSize + 1];
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blockLengthLimit = blockSize - 6; // 5 bytes for one RLE run plus one byte - see {@link #write(int)}
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}
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/**
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* Write the Huffman symbol to output byte map.
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*/
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private void writeSymbolMap(ByteBuf out) {
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Bzip2BitWriter writer = this.writer;
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final boolean[] blockValuesPresent = this.blockValuesPresent;
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final boolean[] condensedInUse = new boolean[16];
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for (int i = 0; i < condensedInUse.length; i++) {
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for (int j = 0, k = i << 4; j < 16; j++, k++) {
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if (blockValuesPresent[k]) {
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condensedInUse[i] = true;
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}
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}
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}
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for (int i = 0; i < condensedInUse.length; i++) {
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writer.writeBoolean(out, condensedInUse[i]);
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}
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for (int i = 0; i < condensedInUse.length; i++) {
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if (condensedInUse[i]) {
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for (int j = 0, k = i << 4; j < 16; j++, k++) {
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writer.writeBoolean(out, blockValuesPresent[k]);
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}
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}
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}
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}
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/**
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* Writes an RLE run to the block array, updating the block CRC and present values array as required.
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* @param value The value to write
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* @param runLength The run length of the value to write
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*/
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private void writeRun(final int value, int runLength) {
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final int blockLength = this.blockLength;
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final byte[] block = this.block;
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blockValuesPresent[value] = true;
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crc.updateCRC(value, runLength);
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final byte byteValue = (byte) value;
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switch (runLength) {
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case 1:
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block[blockLength] = byteValue;
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this.blockLength = blockLength + 1;
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break;
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case 2:
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block[blockLength] = byteValue;
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block[blockLength + 1] = byteValue;
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this.blockLength = blockLength + 2;
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break;
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case 3:
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block[blockLength] = byteValue;
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block[blockLength + 1] = byteValue;
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block[blockLength + 2] = byteValue;
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this.blockLength = blockLength + 3;
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break;
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default:
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runLength -= 4;
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blockValuesPresent[runLength] = true;
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block[blockLength] = byteValue;
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block[blockLength + 1] = byteValue;
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block[blockLength + 2] = byteValue;
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block[blockLength + 3] = byteValue;
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block[blockLength + 4] = (byte) runLength;
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this.blockLength = blockLength + 5;
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break;
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}
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}
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/**
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* Writes a byte to the block, accumulating to an RLE run where possible.
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* @param value The byte to write
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* @return {@code true} if the byte was written, or {@code false} if the block is already full
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*/
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boolean write(final int value) {
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if (blockLength > blockLengthLimit) {
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return false;
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}
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final int rleCurrentValue = this.rleCurrentValue;
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final int rleLength = this.rleLength;
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if (rleLength == 0) {
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this.rleCurrentValue = value;
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this.rleLength = 1;
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} else if (rleCurrentValue != value) {
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// This path commits us to write 6 bytes - one RLE run (5 bytes) plus one extra
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writeRun(rleCurrentValue & 0xff, rleLength);
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this.rleCurrentValue = value;
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this.rleLength = 1;
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} else {
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if (rleLength == 254) {
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writeRun(rleCurrentValue & 0xff, 255);
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this.rleLength = 0;
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} else {
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this.rleLength = rleLength + 1;
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}
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}
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return true;
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}
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/**
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* Writes an array to the block.
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* @param data The array to write
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* @param offset The offset within the input data to write from
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* @param length The number of bytes of input data to write
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* @return The actual number of input bytes written. May be less than the number requested, or
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* zero if the block is already full
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*/
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int write(final byte[] data, int offset, int length) {
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int written = 0;
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while (length-- > 0) {
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if (!write(data[offset++])) {
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break;
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}
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written++;
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}
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return written;
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}
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/**
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* Compresses and writes out the block.
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*/
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void close(ByteBuf out) {
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// If an RLE run is in progress, write it out
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if (rleLength > 0) {
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writeRun(rleCurrentValue & 0xff, rleLength);
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}
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// Apply a one byte block wrap required by the BWT implementation
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block[blockLength] = block[0];
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// Perform the Burrows Wheeler Transform
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Bzip2DivSufSort divSufSort = new Bzip2DivSufSort(block, bwtBlock, blockLength);
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int bwtStartPointer = divSufSort.bwt();
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Bzip2BitWriter writer = this.writer;
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// Write out the block header
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writer.writeBits(out, 24, BLOCK_HEADER_MAGIC_1);
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writer.writeBits(out, 24, BLOCK_HEADER_MAGIC_2);
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writer.writeInt(out, crc.getCRC());
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writer.writeBoolean(out, false); // Randomised block flag. We never create randomised blocks
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writer.writeBits(out, 24, bwtStartPointer);
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// Write out the symbol map
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writeSymbolMap(out);
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// Perform the Move To Front Transform and Run-Length Encoding[2] stages
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Bzip2MTFAndRLE2StageEncoder mtfEncoder = new Bzip2MTFAndRLE2StageEncoder(bwtBlock, blockLength,
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blockValuesPresent);
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mtfEncoder.encode();
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// Perform the Huffman Encoding stage and write out the encoded data
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Bzip2HuffmanStageEncoder huffmanEncoder = new Bzip2HuffmanStageEncoder(writer,
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mtfEncoder.mtfBlock(),
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mtfEncoder.mtfLength(),
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mtfEncoder.mtfAlphabetSize(),
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mtfEncoder.mtfSymbolFrequencies());
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huffmanEncoder.encode(out);
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}
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/**
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* Gets available size of the current block.
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* @return Number of available bytes which can be written
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*/
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int availableSize() {
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if (blockLength == 0) {
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return blockLengthLimit + 2;
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}
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return blockLengthLimit - blockLength + 1;
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}
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/**
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* Determines if the block is full and ready for compression.
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* @return {@code true} if the block is full, otherwise {@code false}
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*/
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boolean isFull() {
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return blockLength > blockLengthLimit;
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}
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/**
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* Determines if any bytes have been written to the block.
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* @return {@code true} if one or more bytes has been written to the block, otherwise {@code false}
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*/
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boolean isEmpty() {
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return blockLength == 0 && rleLength == 0;
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}
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/**
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* Gets the CRC of the completed block. Only valid after calling {@link #close(ByteBuf)}.
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* @return The block's CRC
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*/
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int crc() {
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return crc.getCRC();
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}
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}
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@ -16,7 +16,7 @@
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package io.netty.handler.codec.compression;
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/**
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* Constants for {@link Bzip2Decoder}.
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* Constants for both the {@link Bzip2Encoder} and the {@link Bzip2Decoder}.
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*/
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final class Bzip2Constants {
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@ -28,12 +28,14 @@ final class Bzip2Constants {
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/**
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* Block header magic number. Equals to BCD (pi).
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*/
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static final long COMPRESSED_MAGIC = 0x314159265359L;
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static final int BLOCK_HEADER_MAGIC_1 = 0x314159;
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static final int BLOCK_HEADER_MAGIC_2 = 0x265359;
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/**
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* End of stream magic number. Equals to BCD sqrt(pi).
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*/
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static final long END_OF_STREAM_MAGIC = 0x177245385090L;
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static final int END_OF_STREAM_MAGIC_1 = 0x177245;
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static final int END_OF_STREAM_MAGIC_2 = 0x385090;
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/**
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* Base block size.
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|
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@ -108,8 +108,9 @@ public class Bzip2Decoder extends ByteToMessageDecoder {
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}
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Bzip2BitReader reader = this.reader;
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// Get the block magic bytes.
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final long magic = (long) reader.readBits(in, 24) << 24 | reader.readBits(in, 24);
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if (magic == END_OF_STREAM_MAGIC) {
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final int magic1 = reader.readBits(in, 24);
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final int magic2 = reader.readBits(in, 24);
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if (magic1 == END_OF_STREAM_MAGIC_1 && magic2 == END_OF_STREAM_MAGIC_2) {
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// End of stream was reached. Check the combined CRC.
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final int storedCombinedCRC = reader.readInt(in);
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if (storedCombinedCRC != streamCRC) {
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@ -118,7 +119,7 @@ public class Bzip2Decoder extends ByteToMessageDecoder {
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currentState = State.EOF;
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break;
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}
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if (magic != COMPRESSED_MAGIC) {
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if (magic1 != BLOCK_HEADER_MAGIC_1 || magic2 != BLOCK_HEADER_MAGIC_2) {
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throw new DecompressionException("bad block header");
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}
|
||||
blockCRC = reader.readInt(in);
|
||||
|
|
|
|||
File diff suppressed because it is too large
Load Diff
|
|
@ -0,0 +1,263 @@
|
|||
/*
|
||||
* 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:
|
||||
*
|
||||
* 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 io.netty.handler.codec.compression;
|
||||
|
||||
import io.netty.buffer.ByteBuf;
|
||||
import io.netty.channel.ChannelFuture;
|
||||
import io.netty.channel.ChannelFutureListener;
|
||||
import io.netty.channel.ChannelHandlerContext;
|
||||
import io.netty.channel.ChannelPipeline;
|
||||
import io.netty.channel.ChannelPromise;
|
||||
import io.netty.channel.ChannelPromiseNotifier;
|
||||
import io.netty.handler.codec.MessageToByteEncoder;
|
||||
import io.netty.util.concurrent.EventExecutor;
|
||||
|
||||
import java.util.concurrent.TimeUnit;
|
||||
|
||||
import static io.netty.handler.codec.compression.Bzip2Constants.*;
|
||||
|
||||
/**
|
||||
* Compresses a {@link ByteBuf} using the Bzip2 algorithm.
|
||||
*
|
||||
* See <a href="http://en.wikipedia.org/wiki/Bzip2">Bzip2</a>.
|
||||
*/
|
||||
public class Bzip2Encoder extends MessageToByteEncoder<ByteBuf> {
|
||||
/**
|
||||
* Current state of stream.
|
||||
*/
|
||||
private enum State {
|
||||
INIT,
|
||||
INIT_BLOCK,
|
||||
WRITE_DATA,
|
||||
CLOSE_BLOCK,
|
||||
EOF
|
||||
}
|
||||
|
||||
private State currentState = State.INIT;
|
||||
|
||||
/**
|
||||
* A writer that provides bit-level writes.
|
||||
*/
|
||||
private final Bzip2BitWriter writer = new Bzip2BitWriter();
|
||||
|
||||
/**
|
||||
* The declared maximum block size of the stream (before final run-length decoding).
|
||||
*/
|
||||
private final int streamBlockSize;
|
||||
|
||||
/**
|
||||
* The merged CRC of all blocks compressed so far.
|
||||
*/
|
||||
private int streamCRC;
|
||||
|
||||
/**
|
||||
* The compressor for the current block.
|
||||
*/
|
||||
private Bzip2BlockCompressor blockCompressor;
|
||||
|
||||
/**
|
||||
* (@code true} if the compressed stream has been finished, otherwise {@code false}.
|
||||
*/
|
||||
private volatile boolean finished;
|
||||
|
||||
/**
|
||||
* Used to interact with its {@link ChannelPipeline} and other handlers.
|
||||
*/
|
||||
private volatile ChannelHandlerContext ctx;
|
||||
|
||||
/**
|
||||
* Creates a new bzip2 encoder with the maximum (900,000 byte) block size.
|
||||
*/
|
||||
public Bzip2Encoder() {
|
||||
this(MAX_BLOCK_SIZE);
|
||||
}
|
||||
|
||||
/**
|
||||
* Creates a new bzip2 encoder with the specified {@code blockSizeMultiplier}.
|
||||
* @param blockSizeMultiplier
|
||||
* The Bzip2 block size as a multiple of 100,000 bytes (minimum {@code 1}, maximum {@code 9}).
|
||||
* Larger block sizes require more memory for both compression and decompression,
|
||||
* but give better compression ratios. {@code 9} will usually be the best value to use.
|
||||
*/
|
||||
public Bzip2Encoder(final int blockSizeMultiplier) {
|
||||
if (blockSizeMultiplier < MIN_BLOCK_SIZE || blockSizeMultiplier > MAX_BLOCK_SIZE) {
|
||||
throw new IllegalArgumentException(
|
||||
"blockSizeMultiplier: " + blockSizeMultiplier + " (expected: 1-9)");
|
||||
}
|
||||
streamBlockSize = blockSizeMultiplier * BASE_BLOCK_SIZE;
|
||||
}
|
||||
|
||||
@Override
|
||||
protected void encode(ChannelHandlerContext ctx, ByteBuf in, ByteBuf out) throws Exception {
|
||||
if (finished) {
|
||||
out.writeBytes(in);
|
||||
return;
|
||||
}
|
||||
|
||||
for (;;) {
|
||||
switch (currentState) {
|
||||
case INIT:
|
||||
out.ensureWritable(4);
|
||||
out.writeMedium(MAGIC_NUMBER);
|
||||
out.writeByte('0' + streamBlockSize / BASE_BLOCK_SIZE);
|
||||
currentState = State.INIT_BLOCK;
|
||||
case INIT_BLOCK:
|
||||
blockCompressor = new Bzip2BlockCompressor(writer, streamBlockSize);
|
||||
currentState = State.WRITE_DATA;
|
||||
case WRITE_DATA:
|
||||
if (!in.isReadable()) {
|
||||
return;
|
||||
}
|
||||
Bzip2BlockCompressor blockCompressor = this.blockCompressor;
|
||||
final int length = in.readableBytes() < blockCompressor.availableSize() ?
|
||||
in.readableBytes() : blockCompressor.availableSize();
|
||||
final int offset;
|
||||
final byte[] array;
|
||||
if (in.hasArray()) {
|
||||
array = in.array();
|
||||
offset = in.arrayOffset() + in.readerIndex();
|
||||
} else {
|
||||
array = new byte[length];
|
||||
in.getBytes(in.readerIndex(), array);
|
||||
offset = 0;
|
||||
}
|
||||
final int bytesWritten = blockCompressor.write(array, offset, length);
|
||||
in.skipBytes(bytesWritten);
|
||||
if (!blockCompressor.isFull()) {
|
||||
if (in.isReadable()) {
|
||||
break;
|
||||
} else {
|
||||
return;
|
||||
}
|
||||
}
|
||||
currentState = State.CLOSE_BLOCK;
|
||||
case CLOSE_BLOCK:
|
||||
closeBlock(out);
|
||||
currentState = State.INIT_BLOCK;
|
||||
break;
|
||||
default:
|
||||
throw new IllegalStateException();
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
/**
|
||||
* Close current block and update {@link #streamCRC}.
|
||||
*/
|
||||
private void closeBlock(ByteBuf out) {
|
||||
final Bzip2BlockCompressor blockCompressor = this.blockCompressor;
|
||||
if (!blockCompressor.isEmpty()) {
|
||||
blockCompressor.close(out);
|
||||
final int blockCRC = blockCompressor.crc();
|
||||
streamCRC = (streamCRC << 1 | streamCRC >>> 31) ^ blockCRC;
|
||||
}
|
||||
}
|
||||
|
||||
/**
|
||||
* Returns {@code true} if and only if the end of the compressed stream has been reached.
|
||||
*/
|
||||
public boolean isClosed() {
|
||||
return finished;
|
||||
}
|
||||
|
||||
/**
|
||||
* Close this {@link Bzip2Encoder} and so finish the encoding.
|
||||
*
|
||||
* The returned {@link ChannelFuture} will be notified once the operation completes.
|
||||
*/
|
||||
public ChannelFuture close() {
|
||||
return close(ctx().newPromise());
|
||||
}
|
||||
|
||||
/**
|
||||
* Close this {@link Bzip2Encoder} and so finish the encoding.
|
||||
* The given {@link ChannelFuture} will be notified once the operation
|
||||
* completes and will also be returned.
|
||||
*/
|
||||
public ChannelFuture close(final ChannelPromise promise) {
|
||||
ChannelHandlerContext ctx = ctx();
|
||||
EventExecutor executor = ctx.executor();
|
||||
if (executor.inEventLoop()) {
|
||||
return finishEncode(ctx, promise);
|
||||
} else {
|
||||
executor.execute(new Runnable() {
|
||||
@Override
|
||||
public void run() {
|
||||
ChannelFuture f = finishEncode(ctx(), promise);
|
||||
f.addListener(new ChannelPromiseNotifier(promise));
|
||||
}
|
||||
});
|
||||
return promise;
|
||||
}
|
||||
}
|
||||
|
||||
@Override
|
||||
public void close(final ChannelHandlerContext ctx, final ChannelPromise promise) throws Exception {
|
||||
ChannelFuture f = finishEncode(ctx, ctx.newPromise());
|
||||
f.addListener(new ChannelFutureListener() {
|
||||
@Override
|
||||
public void operationComplete(ChannelFuture f) throws Exception {
|
||||
ctx.close(promise);
|
||||
}
|
||||
});
|
||||
|
||||
if (!f.isDone()) {
|
||||
// Ensure the channel is closed even if the write operation completes in time.
|
||||
ctx.executor().schedule(new Runnable() {
|
||||
@Override
|
||||
public void run() {
|
||||
ctx.close(promise);
|
||||
}
|
||||
}, 10, TimeUnit.SECONDS); // FIXME: Magic number
|
||||
}
|
||||
}
|
||||
|
||||
private ChannelFuture finishEncode(final ChannelHandlerContext ctx, ChannelPromise promise) {
|
||||
if (finished) {
|
||||
promise.setSuccess();
|
||||
return promise;
|
||||
}
|
||||
finished = true;
|
||||
|
||||
final ByteBuf footer = ctx.alloc().buffer();
|
||||
closeBlock(footer);
|
||||
|
||||
final int streamCRC = this.streamCRC;
|
||||
final Bzip2BitWriter writer = this.writer;
|
||||
try {
|
||||
writer.writeBits(footer, 24, END_OF_STREAM_MAGIC_1);
|
||||
writer.writeBits(footer, 24, END_OF_STREAM_MAGIC_2);
|
||||
writer.writeInt(footer, streamCRC);
|
||||
writer.flush(footer);
|
||||
} finally {
|
||||
blockCompressor = null;
|
||||
}
|
||||
return ctx.writeAndFlush(footer, promise);
|
||||
}
|
||||
|
||||
private ChannelHandlerContext ctx() {
|
||||
ChannelHandlerContext ctx = this.ctx;
|
||||
if (ctx == null) {
|
||||
throw new IllegalStateException("not added to a pipeline");
|
||||
}
|
||||
return ctx;
|
||||
}
|
||||
|
||||
@Override
|
||||
public void handlerAdded(ChannelHandlerContext ctx) throws Exception {
|
||||
this.ctx = ctx;
|
||||
}
|
||||
}
|
||||
|
|
@ -0,0 +1,183 @@
|
|||
/*
|
||||
* 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:
|
||||
*
|
||||
* 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 io.netty.handler.codec.compression;
|
||||
|
||||
/**
|
||||
* An in-place, length restricted Canonical Huffman code length allocator.<br>
|
||||
* Based on the algorithm proposed by R. L. Milidi'u, A. A. Pessoa and E. S. Laber in
|
||||
* <a href="http://www-di.inf.puc-rio.br/~laber/public/spire98.ps">In-place Length-Restricted Prefix Coding</a>
|
||||
* and incorporating additional ideas from the implementation of
|
||||
* <a href="http://entropyware.info/shcodec/index.html">shcodec</a> by Simakov Alexander.
|
||||
*/
|
||||
final class Bzip2HuffmanAllocator {
|
||||
/**
|
||||
* @param array The code length array
|
||||
* @param i The input position
|
||||
* @param nodesToMove The number of internal nodes to be relocated
|
||||
* @return The smallest {@code k} such that {@code nodesToMove <= k <= i} and
|
||||
* {@code i <= (array[k] % array.length)}
|
||||
*/
|
||||
private static int first(final int[] array, int i, final int nodesToMove) {
|
||||
final int length = array.length;
|
||||
final int limit = i;
|
||||
int k = array.length - 2;
|
||||
|
||||
while (i >= nodesToMove && array[i] % length > limit) {
|
||||
k = i;
|
||||
i -= limit - i + 1;
|
||||
}
|
||||
i = Math.max(nodesToMove - 1, i);
|
||||
|
||||
while (k > i + 1) {
|
||||
int temp = i + k >> 1;
|
||||
if (array[temp] % length > limit) {
|
||||
k = temp;
|
||||
} else {
|
||||
i = temp;
|
||||
}
|
||||
}
|
||||
return k;
|
||||
}
|
||||
|
||||
/**
|
||||
* Fills the code array with extended parent pointers.
|
||||
* @param array The code length array
|
||||
*/
|
||||
private static void setExtendedParentPointers(final int[] array) {
|
||||
final int length = array.length;
|
||||
array[0] += array[1];
|
||||
|
||||
for (int headNode = 0, tailNode = 1, topNode = 2; tailNode < length - 1; tailNode++) {
|
||||
int temp;
|
||||
if (topNode >= length || array[headNode] < array[topNode]) {
|
||||
temp = array[headNode];
|
||||
array[headNode++] = tailNode;
|
||||
} else {
|
||||
temp = array[topNode++];
|
||||
}
|
||||
|
||||
if (topNode >= length || (headNode < tailNode && array[headNode] < array[topNode])) {
|
||||
temp += array[headNode];
|
||||
array[headNode++] = tailNode + length;
|
||||
} else {
|
||||
temp += array[topNode++];
|
||||
}
|
||||
array[tailNode] = temp;
|
||||
}
|
||||
}
|
||||
|
||||
/**
|
||||
* Finds the number of nodes to relocate in order to achieve a given code length limit.
|
||||
* @param array The code length array
|
||||
* @param maximumLength The maximum bit length for the generated codes
|
||||
* @return The number of nodes to relocate
|
||||
*/
|
||||
private static int findNodesToRelocate(final int[] array, final int maximumLength) {
|
||||
int currentNode = array.length - 2;
|
||||
for (int currentDepth = 1; currentDepth < maximumLength - 1 && currentNode > 1; currentDepth++) {
|
||||
currentNode = first(array, currentNode - 1, 0);
|
||||
}
|
||||
return currentNode;
|
||||
}
|
||||
|
||||
/**
|
||||
* A final allocation pass with no code length limit.
|
||||
* @param array The code length array
|
||||
*/
|
||||
private static void allocateNodeLengths(final int[] array) {
|
||||
int firstNode = array.length - 2;
|
||||
int nextNode = array.length - 1;
|
||||
|
||||
for (int currentDepth = 1, availableNodes = 2; availableNodes > 0; currentDepth++) {
|
||||
final int lastNode = firstNode;
|
||||
firstNode = first(array, lastNode - 1, 0);
|
||||
|
||||
for (int i = availableNodes - (lastNode - firstNode); i > 0; i--) {
|
||||
array[nextNode--] = currentDepth;
|
||||
}
|
||||
|
||||
availableNodes = (lastNode - firstNode) << 1;
|
||||
}
|
||||
}
|
||||
|
||||
/**
|
||||
* A final allocation pass that relocates nodes in order to achieve a maximum code length limit.
|
||||
* @param array The code length array
|
||||
* @param nodesToMove The number of internal nodes to be relocated
|
||||
* @param insertDepth The depth at which to insert relocated nodes
|
||||
*/
|
||||
private static void allocateNodeLengthsWithRelocation(final int[] array,
|
||||
final int nodesToMove, final int insertDepth) {
|
||||
int firstNode = array.length - 2;
|
||||
int nextNode = array.length - 1;
|
||||
int currentDepth = insertDepth == 1 ? 2 : 1;
|
||||
int nodesLeftToMove = insertDepth == 1 ? nodesToMove - 2 : nodesToMove;
|
||||
|
||||
for (int availableNodes = currentDepth << 1; availableNodes > 0; currentDepth++) {
|
||||
final int lastNode = firstNode;
|
||||
firstNode = firstNode <= nodesToMove ? firstNode : first(array, lastNode - 1, nodesToMove);
|
||||
|
||||
int offset = 0;
|
||||
if (currentDepth >= insertDepth) {
|
||||
offset = Math.min(nodesLeftToMove, 1 << (currentDepth - insertDepth));
|
||||
} else if (currentDepth == insertDepth - 1) {
|
||||
offset = 1;
|
||||
if (array[firstNode] == lastNode) {
|
||||
firstNode++;
|
||||
}
|
||||
}
|
||||
|
||||
for (int i = availableNodes - (lastNode - firstNode + offset); i > 0; i--) {
|
||||
array[nextNode--] = currentDepth;
|
||||
}
|
||||
|
||||
nodesLeftToMove -= offset;
|
||||
availableNodes = (lastNode - firstNode + offset) << 1;
|
||||
}
|
||||
}
|
||||
|
||||
/**
|
||||
* Allocates Canonical Huffman code lengths in place based on a sorted frequency array.
|
||||
* @param array On input, a sorted array of symbol frequencies; On output, an array of Canonical
|
||||
* Huffman code lengths
|
||||
* @param maximumLength The maximum code length. Must be at least {@code ceil(log2(array.length))}
|
||||
*/
|
||||
static void allocateHuffmanCodeLengths(final int[] array, final int maximumLength) {
|
||||
switch (array.length) {
|
||||
case 2:
|
||||
array[1] = 1;
|
||||
case 1:
|
||||
array[0] = 1;
|
||||
return;
|
||||
}
|
||||
|
||||
/* Pass 1 : Set extended parent pointers */
|
||||
setExtendedParentPointers(array);
|
||||
|
||||
/* Pass 2 : Find number of nodes to relocate in order to achieve maximum code length */
|
||||
int nodesToRelocate = findNodesToRelocate(array, maximumLength);
|
||||
|
||||
/* Pass 3 : Generate code lengths */
|
||||
if (array[0] % array.length >= nodesToRelocate) {
|
||||
allocateNodeLengths(array);
|
||||
} else {
|
||||
int insertDepth = maximumLength - (32 - Integer.numberOfLeadingZeros(nodesToRelocate - 1));
|
||||
allocateNodeLengthsWithRelocation(array, nodesToRelocate, insertDepth);
|
||||
}
|
||||
}
|
||||
|
||||
private Bzip2HuffmanAllocator() { }
|
||||
}
|
||||
|
|
@ -0,0 +1,374 @@
|
|||
/*
|
||||
* 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:
|
||||
*
|
||||
* 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 io.netty.handler.codec.compression;
|
||||
|
||||
import io.netty.buffer.ByteBuf;
|
||||
|
||||
import java.util.Arrays;
|
||||
|
||||
import static io.netty.handler.codec.compression.Bzip2Constants.*;
|
||||
|
||||
/**
|
||||
* An encoder for the Bzip2 Huffman encoding stage.
|
||||
*/
|
||||
final class Bzip2HuffmanStageEncoder {
|
||||
/**
|
||||
* Used in initial Huffman table generation.
|
||||
*/
|
||||
private static final int HUFFMAN_HIGH_SYMBOL_COST = 15;
|
||||
|
||||
/**
|
||||
* The {@link Bzip2BitWriter} to which the Huffman tables and data is written.
|
||||
*/
|
||||
private final Bzip2BitWriter writer;
|
||||
|
||||
/**
|
||||
* The output of the Move To Front Transform and Run Length Encoding[2] stages.
|
||||
*/
|
||||
private final char[] mtfBlock;
|
||||
|
||||
/**
|
||||
* The actual number of values contained in the {@link #mtfBlock} array.
|
||||
*/
|
||||
private final int mtfLength;
|
||||
|
||||
/**
|
||||
* The number of unique values in the {@link #mtfBlock} array.
|
||||
*/
|
||||
private final int mtfAlphabetSize;
|
||||
|
||||
/**
|
||||
* The global frequencies of values within the {@link #mtfBlock} array.
|
||||
*/
|
||||
private final int[] mtfSymbolFrequencies;
|
||||
|
||||
/**
|
||||
* The Canonical Huffman code lengths for each table.
|
||||
*/
|
||||
private final int[][] huffmanCodeLengths;
|
||||
|
||||
/**
|
||||
* Merged code symbols for each table. The value at each position is ((code length << 24) | code).
|
||||
*/
|
||||
private final int[][] huffmanMergedCodeSymbols;
|
||||
|
||||
/**
|
||||
* The selectors for each segment.
|
||||
*/
|
||||
private final byte[] selectors;
|
||||
|
||||
/**
|
||||
* @param writer The {@link Bzip2BitWriter} which provides bit-level writes
|
||||
* @param mtfBlock The MTF block data
|
||||
* @param mtfLength The actual length of the MTF block
|
||||
* @param mtfAlphabetSize The size of the MTF block's alphabet
|
||||
* @param mtfSymbolFrequencies The frequencies the MTF block's symbols
|
||||
*/
|
||||
Bzip2HuffmanStageEncoder(final Bzip2BitWriter writer, final char[] mtfBlock,
|
||||
final int mtfLength, final int mtfAlphabetSize, final int[] mtfSymbolFrequencies) {
|
||||
this.writer = writer;
|
||||
this.mtfBlock = mtfBlock;
|
||||
this.mtfLength = mtfLength;
|
||||
this.mtfAlphabetSize = mtfAlphabetSize;
|
||||
this.mtfSymbolFrequencies = mtfSymbolFrequencies;
|
||||
|
||||
final int totalTables = selectTableCount(mtfLength);
|
||||
|
||||
huffmanCodeLengths = new int[totalTables][mtfAlphabetSize];
|
||||
huffmanMergedCodeSymbols = new int[totalTables][mtfAlphabetSize];
|
||||
selectors = new byte[(mtfLength + HUFFMAN_GROUP_RUN_LENGTH - 1) / HUFFMAN_GROUP_RUN_LENGTH];
|
||||
}
|
||||
|
||||
/**
|
||||
* Selects an appropriate table count for a given MTF length.
|
||||
* @param mtfLength The length to select a table count for
|
||||
* @return The selected table count
|
||||
*/
|
||||
private static int selectTableCount(final int mtfLength) {
|
||||
if (mtfLength >= 2400) {
|
||||
return 6;
|
||||
}
|
||||
if (mtfLength >= 1200) {
|
||||
return 5;
|
||||
}
|
||||
if (mtfLength >= 600) {
|
||||
return 4;
|
||||
}
|
||||
if (mtfLength >= 200) {
|
||||
return 3;
|
||||
}
|
||||
return 2;
|
||||
}
|
||||
|
||||
/**
|
||||
* Generate a Huffman code length table for a given list of symbol frequencies.
|
||||
* @param alphabetSize The total number of symbols
|
||||
* @param symbolFrequencies The frequencies of the symbols
|
||||
* @param codeLengths The array to which the generated code lengths should be written
|
||||
*/
|
||||
private static void generateHuffmanCodeLengths(final int alphabetSize,
|
||||
final int[] symbolFrequencies, final int[] codeLengths) {
|
||||
|
||||
final int[] mergedFrequenciesAndIndices = new int[alphabetSize];
|
||||
final int[] sortedFrequencies = new int[alphabetSize];
|
||||
|
||||
// The Huffman allocator needs its input symbol frequencies to be sorted, but we need to
|
||||
// return code lengths in the same order as the corresponding frequencies are passed in.
|
||||
|
||||
// The symbol frequency and index are merged into a single array of
|
||||
// integers - frequency in the high 23 bits, index in the low 9 bits.
|
||||
// 2^23 = 8,388,608 which is higher than the maximum possible frequency for one symbol in a block
|
||||
// 2^9 = 512 which is higher than the maximum possible alphabet size (== 258)
|
||||
// Sorting this array simultaneously sorts the frequencies and
|
||||
// leaves a lookup that can be used to cheaply invert the sort.
|
||||
for (int i = 0; i < alphabetSize; i++) {
|
||||
mergedFrequenciesAndIndices[i] = (symbolFrequencies[i] << 9) | i;
|
||||
}
|
||||
Arrays.sort(mergedFrequenciesAndIndices);
|
||||
for (int i = 0; i < alphabetSize; i++) {
|
||||
sortedFrequencies[i] = mergedFrequenciesAndIndices[i] >>> 9;
|
||||
}
|
||||
|
||||
// Allocate code lengths - the allocation is in place,
|
||||
// so the code lengths will be in the sortedFrequencies array afterwards
|
||||
Bzip2HuffmanAllocator.allocateHuffmanCodeLengths(sortedFrequencies, HUFFMAN_ENCODE_MAX_CODE_LENGTH);
|
||||
|
||||
// Reverse the sort to place the code lengths in the same order as the symbols whose frequencies were passed in
|
||||
for (int i = 0; i < alphabetSize; i++) {
|
||||
codeLengths[mergedFrequenciesAndIndices[i] & 0x1ff] = sortedFrequencies[i];
|
||||
}
|
||||
}
|
||||
|
||||
/**
|
||||
* Generate initial Huffman code length tables, giving each table a different low cost section
|
||||
* of the alphabet that is roughly equal in overall cumulative frequency. Note that the initial
|
||||
* tables are invalid for actual Huffman code generation, and only serve as the seed for later
|
||||
* iterative optimisation in {@link #optimiseSelectorsAndHuffmanTables(boolean)}.
|
||||
*/
|
||||
private void generateHuffmanOptimisationSeeds() {
|
||||
final int[][] huffmanCodeLengths = this.huffmanCodeLengths;
|
||||
final int[] mtfSymbolFrequencies = this.mtfSymbolFrequencies;
|
||||
final int mtfAlphabetSize = this.mtfAlphabetSize;
|
||||
|
||||
final int totalTables = huffmanCodeLengths.length;
|
||||
|
||||
int remainingLength = mtfLength;
|
||||
int lowCostEnd = -1;
|
||||
|
||||
for (int i = 0; i < totalTables; i++) {
|
||||
|
||||
final int targetCumulativeFrequency = remainingLength / (totalTables - i);
|
||||
final int lowCostStart = lowCostEnd + 1;
|
||||
int actualCumulativeFrequency = 0;
|
||||
|
||||
while (actualCumulativeFrequency < targetCumulativeFrequency && lowCostEnd < mtfAlphabetSize - 1) {
|
||||
actualCumulativeFrequency += mtfSymbolFrequencies[++lowCostEnd];
|
||||
}
|
||||
|
||||
if (lowCostEnd > lowCostStart && i != 0 && i != totalTables - 1 && (totalTables - i & 1) == 0) {
|
||||
actualCumulativeFrequency -= mtfSymbolFrequencies[lowCostEnd--];
|
||||
}
|
||||
|
||||
final int[] tableCodeLengths = huffmanCodeLengths[i];
|
||||
for (int j = 0; j < mtfAlphabetSize; j++) {
|
||||
if (j < lowCostStart || j > lowCostEnd) {
|
||||
tableCodeLengths[j] = HUFFMAN_HIGH_SYMBOL_COST;
|
||||
}
|
||||
}
|
||||
|
||||
remainingLength -= actualCumulativeFrequency;
|
||||
}
|
||||
}
|
||||
|
||||
/**
|
||||
* Co-optimise the selector list and the alternative Huffman table code lengths. This method is
|
||||
* called repeatedly in the hope that the total encoded size of the selectors, the Huffman code
|
||||
* lengths and the block data encoded with them will converge towards a minimum.<br>
|
||||
* If the data is highly incompressible, it is possible that the total encoded size will
|
||||
* instead diverge (increase) slightly.<br>
|
||||
* @param storeSelectors If {@code true}, write out the (final) chosen selectors
|
||||
*/
|
||||
private void optimiseSelectorsAndHuffmanTables(final boolean storeSelectors) {
|
||||
final char[] mtfBlock = this.mtfBlock;
|
||||
final byte[] selectors = this.selectors;
|
||||
final int[][] huffmanCodeLengths = this.huffmanCodeLengths;
|
||||
final int mtfLength = this.mtfLength;
|
||||
final int mtfAlphabetSize = this.mtfAlphabetSize;
|
||||
|
||||
final int totalTables = huffmanCodeLengths.length;
|
||||
final int[][] tableFrequencies = new int[totalTables][mtfAlphabetSize];
|
||||
|
||||
int selectorIndex = 0;
|
||||
|
||||
// Find the best table for each group of 50 block bytes based on the current Huffman code lengths
|
||||
for (int groupStart = 0; groupStart < mtfLength;) {
|
||||
|
||||
final int groupEnd = Math.min(groupStart + HUFFMAN_GROUP_RUN_LENGTH, mtfLength) - 1;
|
||||
|
||||
// Calculate the cost of this group when encoded by each table
|
||||
short[] cost = new short[totalTables];
|
||||
for (int i = groupStart; i <= groupEnd; i++) {
|
||||
final int value = mtfBlock[i];
|
||||
for (int j = 0; j < totalTables; j++) {
|
||||
cost[j] += huffmanCodeLengths[j][value];
|
||||
}
|
||||
}
|
||||
|
||||
// Find the table with the least cost for this group
|
||||
byte bestTable = 0;
|
||||
int bestCost = cost[0];
|
||||
for (byte i = 1 ; i < totalTables; i++) {
|
||||
final int tableCost = cost[i];
|
||||
if (tableCost < bestCost) {
|
||||
bestCost = tableCost;
|
||||
bestTable = i;
|
||||
}
|
||||
}
|
||||
|
||||
// Accumulate symbol frequencies for the table chosen for this block
|
||||
final int[] bestGroupFrequencies = tableFrequencies[bestTable];
|
||||
for (int i = groupStart; i <= groupEnd; i++) {
|
||||
bestGroupFrequencies[mtfBlock[i]]++;
|
||||
}
|
||||
|
||||
// Store a selector indicating the table chosen for this block
|
||||
if (storeSelectors) {
|
||||
selectors[selectorIndex++] = bestTable;
|
||||
}
|
||||
groupStart = groupEnd + 1;
|
||||
}
|
||||
|
||||
// Generate new Huffman code lengths based on the frequencies for each table accumulated in this iteration
|
||||
for (int i = 0; i < totalTables; i++) {
|
||||
generateHuffmanCodeLengths(mtfAlphabetSize, tableFrequencies[i], huffmanCodeLengths[i]);
|
||||
}
|
||||
}
|
||||
|
||||
/**
|
||||
* Assigns Canonical Huffman codes based on the calculated lengths.
|
||||
*/
|
||||
private void assignHuffmanCodeSymbols() {
|
||||
final int[][] huffmanMergedCodeSymbols = this.huffmanMergedCodeSymbols;
|
||||
final int[][] huffmanCodeLengths = this.huffmanCodeLengths;
|
||||
final int mtfAlphabetSize = this.mtfAlphabetSize;
|
||||
|
||||
final int totalTables = huffmanCodeLengths.length;
|
||||
|
||||
for (int i = 0; i < totalTables; i++) {
|
||||
final int[] tableLengths = huffmanCodeLengths[i];
|
||||
|
||||
int minimumLength = 32;
|
||||
int maximumLength = 0;
|
||||
for (int j = 0; j < mtfAlphabetSize; j++) {
|
||||
final int length = tableLengths[j];
|
||||
if (length > maximumLength) {
|
||||
maximumLength = length;
|
||||
}
|
||||
if (length < minimumLength) {
|
||||
minimumLength = length;
|
||||
}
|
||||
}
|
||||
|
||||
int code = 0;
|
||||
for (int j = minimumLength; j <= maximumLength; j++) {
|
||||
for (int k = 0; k < mtfAlphabetSize; k++) {
|
||||
if ((huffmanCodeLengths[i][k] & 0xff) == j) {
|
||||
huffmanMergedCodeSymbols[i][k] = (j << 24) | code;
|
||||
code++;
|
||||
}
|
||||
}
|
||||
code <<= 1;
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
/**
|
||||
* Write out the selector list and Huffman tables.
|
||||
*/
|
||||
private void writeSelectorsAndHuffmanTables(ByteBuf out) {
|
||||
final Bzip2BitWriter writer = this.writer;
|
||||
final byte[] selectors = this.selectors;
|
||||
final int totalSelectors = selectors.length;
|
||||
final int[][] huffmanCodeLengths = this.huffmanCodeLengths;
|
||||
final int totalTables = huffmanCodeLengths.length;
|
||||
final int mtfAlphabetSize = this.mtfAlphabetSize;
|
||||
|
||||
writer.writeBits(out, 3, totalTables);
|
||||
writer.writeBits(out, 15, totalSelectors);
|
||||
|
||||
// Write the selectors
|
||||
Bzip2MoveToFrontTable selectorMTF = new Bzip2MoveToFrontTable();
|
||||
for (byte selector : selectors) {
|
||||
writer.writeUnary(out, selectorMTF.valueToFront(selector));
|
||||
}
|
||||
|
||||
// Write the Huffman tables
|
||||
for (final int[] tableLengths : huffmanCodeLengths) {
|
||||
int currentLength = tableLengths[0];
|
||||
|
||||
writer.writeBits(out, 5, currentLength);
|
||||
|
||||
for (int j = 0; j < mtfAlphabetSize; j++) {
|
||||
final int codeLength = tableLengths[j];
|
||||
final int value = currentLength < codeLength ? 2 : 3;
|
||||
int delta = Math.abs(codeLength - currentLength);
|
||||
while (delta-- > 0) {
|
||||
writer.writeBits(out, 2, value);
|
||||
}
|
||||
writer.writeBoolean(out, false);
|
||||
currentLength = codeLength;
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
/**
|
||||
* Writes out the encoded block data.
|
||||
*/
|
||||
private void writeBlockData(ByteBuf out) {
|
||||
final Bzip2BitWriter writer = this.writer;
|
||||
final int[][] huffmanMergedCodeSymbols = this.huffmanMergedCodeSymbols;
|
||||
final byte[] selectors = this.selectors;
|
||||
final char[] mtf = mtfBlock;
|
||||
final int mtfLength = this.mtfLength;
|
||||
|
||||
int selectorIndex = 0;
|
||||
for (int mtfIndex = 0; mtfIndex < mtfLength;) {
|
||||
final int groupEnd = Math.min(mtfIndex + HUFFMAN_GROUP_RUN_LENGTH, mtfLength) - 1;
|
||||
final int[] tableMergedCodeSymbols = huffmanMergedCodeSymbols[selectors[selectorIndex++]];
|
||||
|
||||
while (mtfIndex <= groupEnd) {
|
||||
final int mergedCodeSymbol = tableMergedCodeSymbols[mtf[mtfIndex++]];
|
||||
writer.writeBits(out, mergedCodeSymbol >>> 24, mergedCodeSymbol);
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
/**
|
||||
* Encodes and writes the block data.
|
||||
*/
|
||||
void encode(ByteBuf out) {
|
||||
// Create optimised selector list and Huffman tables
|
||||
generateHuffmanOptimisationSeeds();
|
||||
for (int i = 3; i >= 0; i--) {
|
||||
optimiseSelectorsAndHuffmanTables(i == 0);
|
||||
}
|
||||
assignHuffmanCodeSymbols();
|
||||
|
||||
// Write out the tables and the block data encoded with them
|
||||
writeSelectorsAndHuffmanTables(out);
|
||||
writeBlockData(out);
|
||||
}
|
||||
}
|
||||
|
|
@ -0,0 +1,183 @@
|
|||
/*
|
||||
* 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:
|
||||
*
|
||||
* 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 io.netty.handler.codec.compression;
|
||||
|
||||
import static io.netty.handler.codec.compression.Bzip2Constants.*;
|
||||
|
||||
/**
|
||||
* An encoder for the Bzip2 Move To Front Transform and Run-Length Encoding[2] stages.<br>
|
||||
* Although conceptually these two stages are separate, it is computationally efficient to perform
|
||||
* them in one pass.
|
||||
*/
|
||||
final class Bzip2MTFAndRLE2StageEncoder {
|
||||
/**
|
||||
* The Burrows-Wheeler transformed block.
|
||||
*/
|
||||
private final int[] bwtBlock;
|
||||
|
||||
/**
|
||||
* Actual length of the data in the {@link #bwtBlock} array.
|
||||
*/
|
||||
private final int bwtLength;
|
||||
|
||||
/**
|
||||
* At each position, {@code true} if the byte value with that index is present within the block,
|
||||
* otherwise {@code false}.
|
||||
*/
|
||||
private final boolean[] bwtValuesPresent;
|
||||
|
||||
/**
|
||||
* The output of the Move To Front Transform and Run-Length Encoding[2] stages.
|
||||
*/
|
||||
private final char[] mtfBlock;
|
||||
|
||||
/**
|
||||
* The actual number of values contained in the {@link #mtfBlock} array.
|
||||
*/
|
||||
private int mtfLength;
|
||||
|
||||
/**
|
||||
* The global frequencies of values within the {@link #mtfBlock} array.
|
||||
*/
|
||||
private final int[] mtfSymbolFrequencies = new int[HUFFMAN_MAX_ALPHABET_SIZE];
|
||||
|
||||
/**
|
||||
* The encoded alphabet size.
|
||||
*/
|
||||
private int alphabetSize;
|
||||
|
||||
/**
|
||||
* @param bwtBlock The Burrows Wheeler Transformed block data
|
||||
* @param bwtLength The actual length of the BWT data
|
||||
* @param bwtValuesPresent The values that are present within the BWT data. For each index,
|
||||
* {@code true} if that value is present within the data, otherwise {@code false}
|
||||
*/
|
||||
Bzip2MTFAndRLE2StageEncoder(final int[] bwtBlock, final int bwtLength, final boolean[] bwtValuesPresent) {
|
||||
this.bwtBlock = bwtBlock;
|
||||
this.bwtLength = bwtLength;
|
||||
this.bwtValuesPresent = bwtValuesPresent;
|
||||
mtfBlock = new char[bwtLength + 1];
|
||||
}
|
||||
|
||||
/**
|
||||
* Performs the Move To Front transform and Run Length Encoding[1] stages.
|
||||
*/
|
||||
void encode() {
|
||||
final int bwtLength = this.bwtLength;
|
||||
final boolean[] bwtValuesPresent = this.bwtValuesPresent;
|
||||
final int[] bwtBlock = this.bwtBlock;
|
||||
final char[] mtfBlock = this.mtfBlock;
|
||||
final int[] mtfSymbolFrequencies = this.mtfSymbolFrequencies;
|
||||
final byte[] huffmanSymbolMap = new byte[256];
|
||||
final Bzip2MoveToFrontTable symbolMTF = new Bzip2MoveToFrontTable();
|
||||
|
||||
int totalUniqueValues = 0;
|
||||
for (int i = 0; i < huffmanSymbolMap.length; i++) {
|
||||
if (bwtValuesPresent[i]) {
|
||||
huffmanSymbolMap[i] = (byte) totalUniqueValues++;
|
||||
}
|
||||
}
|
||||
final int endOfBlockSymbol = totalUniqueValues + 1;
|
||||
|
||||
int mtfIndex = 0;
|
||||
int repeatCount = 0;
|
||||
int totalRunAs = 0;
|
||||
int totalRunBs = 0;
|
||||
for (int i = 0; i < bwtLength; i++) {
|
||||
// Move To Front
|
||||
final int mtfPosition = symbolMTF.valueToFront(huffmanSymbolMap[bwtBlock[i] & 0xff]);
|
||||
// Run Length Encode
|
||||
if (mtfPosition == 0) {
|
||||
repeatCount++;
|
||||
} else {
|
||||
if (repeatCount > 0) {
|
||||
repeatCount--;
|
||||
while (true) {
|
||||
if ((repeatCount & 1) == 0) {
|
||||
mtfBlock[mtfIndex++] = HUFFMAN_SYMBOL_RUNA;
|
||||
totalRunAs++;
|
||||
} else {
|
||||
mtfBlock[mtfIndex++] = HUFFMAN_SYMBOL_RUNB;
|
||||
totalRunBs++;
|
||||
}
|
||||
|
||||
if (repeatCount <= 1) {
|
||||
break;
|
||||
}
|
||||
repeatCount = (repeatCount - 2) >>> 1;
|
||||
}
|
||||
repeatCount = 0;
|
||||
}
|
||||
mtfBlock[mtfIndex++] = (char) (mtfPosition + 1);
|
||||
mtfSymbolFrequencies[mtfPosition + 1]++;
|
||||
}
|
||||
}
|
||||
|
||||
if (repeatCount > 0) {
|
||||
repeatCount--;
|
||||
while (true) {
|
||||
if ((repeatCount & 1) == 0) {
|
||||
mtfBlock[mtfIndex++] = HUFFMAN_SYMBOL_RUNA;
|
||||
totalRunAs++;
|
||||
} else {
|
||||
mtfBlock[mtfIndex++] = HUFFMAN_SYMBOL_RUNB;
|
||||
totalRunBs++;
|
||||
}
|
||||
|
||||
if (repeatCount <= 1) {
|
||||
break;
|
||||
}
|
||||
repeatCount = (repeatCount - 2) >>> 1;
|
||||
}
|
||||
}
|
||||
|
||||
mtfBlock[mtfIndex] = (char) endOfBlockSymbol;
|
||||
mtfSymbolFrequencies[endOfBlockSymbol]++;
|
||||
mtfSymbolFrequencies[HUFFMAN_SYMBOL_RUNA] += totalRunAs;
|
||||
mtfSymbolFrequencies[HUFFMAN_SYMBOL_RUNB] += totalRunBs;
|
||||
|
||||
mtfLength = mtfIndex + 1;
|
||||
alphabetSize = endOfBlockSymbol + 1;
|
||||
}
|
||||
|
||||
/**
|
||||
* @return The encoded MTF block
|
||||
*/
|
||||
char[] mtfBlock() {
|
||||
return mtfBlock;
|
||||
}
|
||||
|
||||
/**
|
||||
* @return The actual length of the MTF block
|
||||
*/
|
||||
int mtfLength() {
|
||||
return mtfLength;
|
||||
}
|
||||
|
||||
/**
|
||||
* @return The size of the MTF block's alphabet
|
||||
*/
|
||||
int mtfAlphabetSize() {
|
||||
return alphabetSize;
|
||||
}
|
||||
|
||||
/**
|
||||
* @return The frequencies of the MTF block's symbols
|
||||
*/
|
||||
int[] mtfSymbolFrequencies() {
|
||||
return mtfSymbolFrequencies;
|
||||
}
|
||||
}
|
||||
|
|
@ -18,7 +18,7 @@ package io.netty.handler.codec.compression;
|
|||
/**
|
||||
* A 256 entry Move To Front transform.
|
||||
*/
|
||||
class Bzip2MoveToFrontTable {
|
||||
final class Bzip2MoveToFrontTable {
|
||||
/**
|
||||
* The Move To Front list.
|
||||
*/
|
||||
|
|
|
|||
|
|
@ -21,4 +21,4 @@
|
|||
* <a href="http://code.google.com/p/snappy/">Snappy</a>.
|
||||
*/
|
||||
package io.netty.handler.codec.compression;
|
||||
// TODO Implement bzip2 and lzma handlers
|
||||
// TODO Implement lzma handler
|
||||
|
|
|
|||
|
|
@ -16,6 +16,7 @@
|
|||
package io.netty.handler.codec.compression;
|
||||
|
||||
import io.netty.buffer.ByteBuf;
|
||||
import io.netty.buffer.CompositeByteBuf;
|
||||
import io.netty.buffer.Unpooled;
|
||||
import io.netty.channel.embedded.EmbeddedChannel;
|
||||
import io.netty.util.internal.ThreadLocalRandom;
|
||||
|
|
@ -84,9 +85,9 @@ public class Bzip2DecoderTest {
|
|||
ByteBuf in = Unpooled.buffer();
|
||||
in.writeMedium(MAGIC_NUMBER);
|
||||
in.writeByte('1'); //block size
|
||||
in.writeInt(11111); //random value
|
||||
in.writeShort(111); //random value
|
||||
in.writeInt(111); //block CRC
|
||||
in.writeMedium(11); //incorrect block header
|
||||
in.writeMedium(11); //incorrect block header
|
||||
in.writeInt(11111); //block CRC
|
||||
|
||||
channel.writeInbound(in);
|
||||
}
|
||||
|
|
@ -99,8 +100,8 @@ public class Bzip2DecoderTest {
|
|||
ByteBuf in = Unpooled.buffer();
|
||||
in.writeMedium(MAGIC_NUMBER);
|
||||
in.writeByte('1'); //block size
|
||||
in.writeInt((int) (END_OF_STREAM_MAGIC >> 16));
|
||||
in.writeShort((int) END_OF_STREAM_MAGIC);
|
||||
in.writeMedium(END_OF_STREAM_MAGIC_1);
|
||||
in.writeMedium(END_OF_STREAM_MAGIC_2);
|
||||
in.writeInt(1); //wrong storedCombinedCRC
|
||||
|
||||
channel.writeInbound(in);
|
||||
|
|
@ -181,6 +182,22 @@ public class Bzip2DecoderTest {
|
|||
channel.writeInbound(in);
|
||||
}
|
||||
|
||||
@Test
|
||||
public void testStartPointerInvalid() throws Exception {
|
||||
expected.expect(DecompressionException.class);
|
||||
expected.expectMessage("start pointer invalid");
|
||||
|
||||
final byte[] data = { 0x42, 0x5A, 0x68, 0x37, 0x31, 0x41, 0x59, 0x26, 0x53,
|
||||
0x59, 0x77, 0x7B, (byte) 0xCA, (byte) 0xC0, (byte) 0xFF, 0x00,
|
||||
0x00, 0x05, (byte) 0x80, 0x00, 0x01, 0x02, 0x00, 0x04,
|
||||
0x20, 0x20, 0x00, 0x30, (byte) 0xCD, 0x34, 0x19, (byte) 0xA6,
|
||||
(byte) 0x89, (byte) 0x99, (byte) 0xC5, (byte) 0xDC, (byte) 0x91,
|
||||
0x4E, 0x14, 0x24, 0x1D, (byte) 0xDE, (byte) 0xF2, (byte) 0xB0, 0x00 };
|
||||
|
||||
ByteBuf in = Unpooled.wrappedBuffer(data);
|
||||
channel.writeInbound(in);
|
||||
}
|
||||
|
||||
private static void testDecompression(final byte[] data) throws Exception {
|
||||
for (int blockSize = MIN_BLOCK_SIZE; blockSize <= MAX_BLOCK_SIZE; blockSize++) {
|
||||
final EmbeddedChannel channel = new EmbeddedChannel(new Bzip2Decoder());
|
||||
|
|
@ -193,17 +210,13 @@ public class Bzip2DecoderTest {
|
|||
ByteBuf compressed = Unpooled.wrappedBuffer(os.toByteArray());
|
||||
channel.writeInbound(compressed);
|
||||
|
||||
ByteBuf uncompressed = Unpooled.buffer();
|
||||
ByteBuf msg;
|
||||
while ((msg = channel.readInbound()) != null) {
|
||||
uncompressed.writeBytes(msg);
|
||||
msg.release();
|
||||
}
|
||||
final byte[] result = new byte[uncompressed.readableBytes()];
|
||||
uncompressed.readBytes(result);
|
||||
uncompressed.release();
|
||||
ByteBuf uncompressed = readUncompressed(channel);
|
||||
ByteBuf dataBuf = Unpooled.wrappedBuffer(data);
|
||||
|
||||
assertArrayEquals(data, result);
|
||||
assertEquals(dataBuf, uncompressed);
|
||||
|
||||
uncompressed.release();
|
||||
dataBuf.release();
|
||||
}
|
||||
}
|
||||
|
||||
|
|
@ -219,10 +232,12 @@ public class Bzip2DecoderTest {
|
|||
|
||||
@Test
|
||||
public void testDecompressionOfBatchedFlowOfData() throws Exception {
|
||||
final byte[] data = BYTES_LARGE;
|
||||
|
||||
ByteArrayOutputStream os = new ByteArrayOutputStream();
|
||||
BZip2CompressorOutputStream bZip2Os = new BZip2CompressorOutputStream(os,
|
||||
rand.nextInt(MIN_BLOCK_SIZE, MAX_BLOCK_SIZE + 1));
|
||||
bZip2Os.write(BYTES_LARGE);
|
||||
bZip2Os.write(data);
|
||||
bZip2Os.close();
|
||||
|
||||
final byte[] compressedArray = os.toByteArray();
|
||||
|
|
@ -236,16 +251,23 @@ public class Bzip2DecoderTest {
|
|||
ByteBuf compressed = Unpooled.wrappedBuffer(compressedArray, written, compressedArray.length - written);
|
||||
channel.writeInbound(compressed);
|
||||
|
||||
ByteBuf uncompressed = Unpooled.buffer();
|
||||
ByteBuf uncompressed = readUncompressed(channel);
|
||||
ByteBuf dataBuf = Unpooled.wrappedBuffer(data);
|
||||
|
||||
assertEquals(dataBuf, uncompressed);
|
||||
|
||||
uncompressed.release();
|
||||
dataBuf.release();
|
||||
}
|
||||
|
||||
private static ByteBuf readUncompressed(EmbeddedChannel channel) throws Exception {
|
||||
CompositeByteBuf uncompressed = Unpooled.compositeBuffer();
|
||||
ByteBuf msg;
|
||||
while ((msg = channel.readInbound()) != null) {
|
||||
uncompressed.writeBytes(msg);
|
||||
msg.release();
|
||||
uncompressed.addComponent(msg);
|
||||
uncompressed.writerIndex(uncompressed.writerIndex() + msg.readableBytes());
|
||||
}
|
||||
final byte[] result = new byte[uncompressed.readableBytes()];
|
||||
uncompressed.readBytes(result);
|
||||
uncompressed.release();
|
||||
|
||||
assertArrayEquals(BYTES_LARGE, result);
|
||||
return uncompressed;
|
||||
}
|
||||
}
|
||||
|
|
|
|||
|
|
@ -0,0 +1,134 @@
|
|||
/*
|
||||
* 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:
|
||||
*
|
||||
* 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 io.netty.handler.codec.compression;
|
||||
|
||||
import io.netty.buffer.ByteBuf;
|
||||
import io.netty.buffer.CompositeByteBuf;
|
||||
import io.netty.buffer.Unpooled;
|
||||
import io.netty.channel.embedded.EmbeddedChannel;
|
||||
import io.netty.util.internal.ThreadLocalRandom;
|
||||
import org.apache.commons.compress.compressors.bzip2.BZip2CompressorInputStream;
|
||||
import org.junit.Test;
|
||||
|
||||
import java.io.ByteArrayInputStream;
|
||||
|
||||
import static io.netty.handler.codec.compression.Bzip2Constants.*;
|
||||
import static org.junit.Assert.*;
|
||||
|
||||
public class Bzip2EncoderTest {
|
||||
|
||||
private static final ThreadLocalRandom rand;
|
||||
|
||||
private static final byte[] BYTES_SMALL = new byte[256];
|
||||
private static final byte[] BYTES_LARGE = new byte[MAX_BLOCK_SIZE * BASE_BLOCK_SIZE * 2];
|
||||
|
||||
static {
|
||||
rand = ThreadLocalRandom.current();
|
||||
rand.nextBytes(BYTES_SMALL);
|
||||
rand.nextBytes(BYTES_LARGE);
|
||||
}
|
||||
|
||||
@Test
|
||||
public void testStreamInitialization() throws Exception {
|
||||
final EmbeddedChannel channel = new EmbeddedChannel(new Bzip2Encoder());
|
||||
|
||||
ByteBuf in = Unpooled.wrappedBuffer("test".getBytes());
|
||||
channel.writeOutbound(in);
|
||||
|
||||
ByteBuf out = channel.readOutbound();
|
||||
|
||||
assertEquals(MAGIC_NUMBER, out.readMedium());
|
||||
assertEquals(9 + '0', out.readByte());
|
||||
|
||||
out.release();
|
||||
channel.finish();
|
||||
}
|
||||
|
||||
private static void testCompression(final byte[] data) throws Exception {
|
||||
for (int blockSize = MIN_BLOCK_SIZE; blockSize <= MAX_BLOCK_SIZE; blockSize++) {
|
||||
final EmbeddedChannel channel = new EmbeddedChannel(new Bzip2Encoder(blockSize));
|
||||
|
||||
ByteBuf in = Unpooled.wrappedBuffer(data);
|
||||
channel.writeOutbound(in);
|
||||
channel.finish();
|
||||
|
||||
byte[] uncompressed = uncompress(channel, data.length);
|
||||
|
||||
assertArrayEquals(data, uncompressed);
|
||||
}
|
||||
}
|
||||
|
||||
@Test
|
||||
public void testCompressionOfSmallChunkOfData() throws Exception {
|
||||
testCompression(BYTES_SMALL);
|
||||
}
|
||||
|
||||
@Test
|
||||
public void testCompressionOfLargeChunkOfData() throws Exception {
|
||||
testCompression(BYTES_LARGE);
|
||||
}
|
||||
|
||||
@Test
|
||||
public void testCompressionOfBatchedFlowOfData() throws Exception {
|
||||
final EmbeddedChannel channel = new EmbeddedChannel(new Bzip2Encoder(
|
||||
rand.nextInt(MIN_BLOCK_SIZE, MAX_BLOCK_SIZE + 1)));
|
||||
|
||||
int written = 0, length = rand.nextInt(100);
|
||||
while (written + length < BYTES_LARGE.length) {
|
||||
ByteBuf in = Unpooled.wrappedBuffer(BYTES_LARGE, written, length);
|
||||
channel.writeOutbound(in);
|
||||
written += length;
|
||||
length = rand.nextInt(100);
|
||||
}
|
||||
ByteBuf in = Unpooled.wrappedBuffer(BYTES_LARGE, written, BYTES_LARGE.length - written);
|
||||
channel.writeOutbound(in);
|
||||
channel.finish();
|
||||
|
||||
byte[] uncompressed = uncompress(channel, BYTES_LARGE.length);
|
||||
|
||||
assertArrayEquals(BYTES_LARGE, uncompressed);
|
||||
}
|
||||
|
||||
private static byte[] uncompress(EmbeddedChannel channel, int length) throws Exception {
|
||||
CompositeByteBuf out = Unpooled.compositeBuffer();
|
||||
ByteBuf msg;
|
||||
while ((msg = channel.readOutbound()) != null) {
|
||||
out.addComponent(msg);
|
||||
out.writerIndex(out.writerIndex() + msg.readableBytes());
|
||||
}
|
||||
|
||||
byte[] compressed = new byte[out.readableBytes()];
|
||||
out.readBytes(compressed);
|
||||
out.release();
|
||||
|
||||
ByteArrayInputStream is = new ByteArrayInputStream(compressed);
|
||||
BZip2CompressorInputStream bZip2Is = new BZip2CompressorInputStream(is);
|
||||
byte[] uncompressed = new byte[length];
|
||||
int remaining = length;
|
||||
while (remaining > 0) {
|
||||
int read = bZip2Is.read(uncompressed, length - remaining, remaining);
|
||||
if (read > 0) {
|
||||
remaining -= read;
|
||||
} else {
|
||||
break;
|
||||
}
|
||||
}
|
||||
|
||||
assertEquals(-1, bZip2Is.read());
|
||||
|
||||
return uncompressed;
|
||||
}
|
||||
}
|
||||
|
|
@ -0,0 +1,178 @@
|
|||
/*
|
||||
* 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:
|
||||
*
|
||||
* 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 io.netty.handler.codec.compression;
|
||||
|
||||
import io.netty.buffer.ByteBuf;
|
||||
import io.netty.buffer.CompositeByteBuf;
|
||||
import io.netty.buffer.Unpooled;
|
||||
import io.netty.channel.embedded.EmbeddedChannel;
|
||||
import io.netty.util.ReferenceCountUtil;
|
||||
import io.netty.util.internal.ThreadLocalRandom;
|
||||
import org.junit.Test;
|
||||
|
||||
import java.util.Arrays;
|
||||
|
||||
import static org.hamcrest.Matchers.*;
|
||||
import static org.junit.Assert.*;
|
||||
|
||||
public class Bzip2IntegrationTest {
|
||||
|
||||
private static final ThreadLocalRandom rand = ThreadLocalRandom.current();
|
||||
|
||||
public static final byte[] EMPTY = new byte[0];
|
||||
|
||||
@Test
|
||||
public void testEmpty() throws Exception {
|
||||
testIdentity(EMPTY);
|
||||
}
|
||||
|
||||
@Test
|
||||
public void testOneByte() throws Exception {
|
||||
testIdentity(new byte[] { 'A' });
|
||||
}
|
||||
|
||||
@Test
|
||||
public void testTwoBytes() throws Exception {
|
||||
testIdentity(new byte[] { 'B', 'A' });
|
||||
}
|
||||
|
||||
@Test
|
||||
public void testRegular() throws Exception {
|
||||
byte[] data = ("Netty is a NIO client server framework which enables quick and easy development " +
|
||||
"of network applications such as protocol servers and clients.").getBytes();
|
||||
testIdentity(data);
|
||||
}
|
||||
|
||||
@Test
|
||||
public void test3Tables() throws Exception {
|
||||
byte[] data = new byte[500];
|
||||
rand.nextBytes(data);
|
||||
testIdentity(data);
|
||||
}
|
||||
|
||||
@Test
|
||||
public void test4Tables() throws Exception {
|
||||
byte[] data = new byte[1100];
|
||||
rand.nextBytes(data);
|
||||
testIdentity(data);
|
||||
}
|
||||
|
||||
@Test
|
||||
public void test5Tables() throws Exception {
|
||||
byte[] data = new byte[2300];
|
||||
rand.nextBytes(data);
|
||||
testIdentity(data);
|
||||
}
|
||||
|
||||
@Test
|
||||
public void testLargeRandom() throws Exception {
|
||||
byte[] data = new byte[1048576];
|
||||
rand.nextBytes(data);
|
||||
testIdentity(data);
|
||||
}
|
||||
|
||||
@Test
|
||||
public void testPartRandom() throws Exception {
|
||||
byte[] data = new byte[12345];
|
||||
rand.nextBytes(data);
|
||||
for (int i = 0; i < 1024; i++) {
|
||||
data[i] = 123;
|
||||
}
|
||||
testIdentity(data);
|
||||
}
|
||||
|
||||
@Test
|
||||
public void testCompressible() throws Exception {
|
||||
byte[] data = new byte[10000];
|
||||
for (int i = 0; i < data.length; i++) {
|
||||
data[i] = i % 4 != 0 ? 0 : (byte) rand.nextInt();
|
||||
}
|
||||
testIdentity(data);
|
||||
}
|
||||
|
||||
@Test
|
||||
public void testLongBlank() throws Exception {
|
||||
byte[] data = new byte[100000];
|
||||
testIdentity(data);
|
||||
}
|
||||
|
||||
@Test
|
||||
public void testLongSame() throws Exception {
|
||||
byte[] data = new byte[100000];
|
||||
Arrays.fill(data, (byte) 123);
|
||||
testIdentity(data);
|
||||
}
|
||||
|
||||
@Test
|
||||
public void testSequential() throws Exception {
|
||||
byte[] data = new byte[49];
|
||||
for (int i = 0; i < data.length; i++) {
|
||||
data[i] = (byte) i;
|
||||
}
|
||||
testIdentity(data);
|
||||
}
|
||||
|
||||
private static void testIdentity(byte[] data) {
|
||||
ByteBuf in = Unpooled.wrappedBuffer(data);
|
||||
EmbeddedChannel encoder = new EmbeddedChannel(new Bzip2Encoder());
|
||||
EmbeddedChannel decoder = new EmbeddedChannel(new Bzip2Decoder());
|
||||
try {
|
||||
ByteBuf msg;
|
||||
|
||||
encoder.writeOutbound(in.copy());
|
||||
encoder.finish();
|
||||
CompositeByteBuf compressed = Unpooled.compositeBuffer();
|
||||
while ((msg = encoder.readOutbound()) != null) {
|
||||
compressed.addComponent(msg);
|
||||
compressed.writerIndex(compressed.writerIndex() + msg.readableBytes());
|
||||
}
|
||||
assertThat(compressed, is(notNullValue()));
|
||||
assertThat(compressed, is(not(in)));
|
||||
|
||||
decoder.writeInbound(compressed.retain());
|
||||
assertFalse(compressed.isReadable());
|
||||
CompositeByteBuf decompressed = Unpooled.compositeBuffer();
|
||||
while ((msg = decoder.readInbound()) != null) {
|
||||
decompressed.addComponent(msg);
|
||||
decompressed.writerIndex(decompressed.writerIndex() + msg.readableBytes());
|
||||
}
|
||||
assertEquals(in, decompressed);
|
||||
|
||||
compressed.release();
|
||||
decompressed.release();
|
||||
in.release();
|
||||
} finally {
|
||||
encoder.close();
|
||||
decoder.close();
|
||||
|
||||
for (;;) {
|
||||
Object msg = encoder.readOutbound();
|
||||
if (msg == null) {
|
||||
break;
|
||||
}
|
||||
ReferenceCountUtil.release(msg);
|
||||
}
|
||||
|
||||
for (;;) {
|
||||
Object msg = decoder.readInbound();
|
||||
if (msg == null) {
|
||||
break;
|
||||
}
|
||||
ReferenceCountUtil.release(msg);
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
||||
|
|
@ -0,0 +1,22 @@
|
|||
Copyright (c) 2003-2008 Yuta Mori All Rights Reserved.
|
||||
|
||||
Permission is hereby granted, free of charge, to any person
|
||||
obtaining a copy of this software and associated documentation
|
||||
files (the "Software"), to deal in the Software without
|
||||
restriction, including without limitation the rights to use,
|
||||
copy, modify, merge, publish, distribute, sublicense, and/or sell
|
||||
copies of the Software, and to permit persons to whom the
|
||||
Software is furnished to do so, subject to the following
|
||||
conditions:
|
||||
|
||||
The above copyright notice and this permission notice shall be
|
||||
included in all copies or substantial portions of the Software.
|
||||
|
||||
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
|
||||
EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
|
||||
OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
|
||||
NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
|
||||
HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
|
||||
WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
|
||||
FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
|
||||
OTHER DEALINGS IN THE SOFTWARE.
|
||||
Loading…
Reference in New Issue