emkornfield commented on a change in pull request #8949: URL: https://github.com/apache/arrow/pull/8949#discussion_r595777904
########## File path: java/compression/src/main/java/org/apache/arrow/compression/Lz4CompressionCodec.java ########## @@ -0,0 +1,158 @@ +/* + * Licensed to the Apache Software Foundation (ASF) under one or more + * contributor license agreements. See the NOTICE file distributed with + * this work for additional information regarding copyright ownership. + * The ASF 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 org.apache.arrow.compression; + +import java.io.ByteArrayInputStream; +import java.io.ByteArrayOutputStream; +import java.io.IOException; +import java.io.InputStream; +import java.io.OutputStream; + +import org.apache.arrow.flatbuf.CompressionType; +import org.apache.arrow.memory.ArrowBuf; +import org.apache.arrow.memory.BufferAllocator; +import org.apache.arrow.memory.util.MemoryUtil; +import org.apache.arrow.util.Preconditions; +import org.apache.arrow.vector.compression.CompressionCodec; +import org.apache.arrow.vector.compression.CompressionUtil; +import org.apache.commons.compress.compressors.lz4.FramedLZ4CompressorInputStream; +import org.apache.commons.compress.compressors.lz4.FramedLZ4CompressorOutputStream; +import org.apache.commons.compress.utils.IOUtils; + +import io.netty.util.internal.PlatformDependent; Review comment: ahh this is where netty is used. we don't have an arrow wrapper for it? ########## File path: java/compression/pom.xml ########## @@ -0,0 +1,56 @@ +<?xml version="1.0"?> +<!-- Licensed to the Apache Software Foundation (ASF) under one or more contributor + license agreements. See the NOTICE file distributed with this work for additional + information regarding copyright ownership. The ASF 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. --> +<project xmlns="http://maven.apache.org/POM/4.0.0"; xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"; xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd";> + <modelVersion>4.0.0</modelVersion> + <parent> + <groupId>org.apache.arrow</groupId> + <artifactId>arrow-java-root</artifactId> + <version>4.0.0-SNAPSHOT</version> + </parent> + <artifactId>arrow-compression</artifactId> + <name>Arrow Compression</name> + <description>(Experimental/Contrib) A library for working with the compression/decompression of Arrow data.</description> + + <dependencies> + <dependency> + <groupId>org.apache.arrow</groupId> + <artifactId>arrow-format</artifactId> + <version>${project.version}</version> + </dependency> + <dependency> + <groupId>org.apache.arrow</groupId> + <artifactId>arrow-vector</artifactId> + <version>${project.version}</version> + <classifier>${arrow.vector.classifier}</classifier> + </dependency> + <dependency> + <groupId>org.apache.arrow</groupId> + <artifactId>arrow-memory-core</artifactId> + <version>${project.version}</version> + </dependency> + <dependency> + <groupId>org.apache.arrow</groupId> + <artifactId>arrow-memory-unsafe</artifactId> + <version>${project.version}</version> + <scope>test</scope> + </dependency> + <dependency> + <groupId>org.apache.commons</groupId> + <artifactId>commons-compress</artifactId> + <version>1.20</version> + </dependency> + <dependency> + <groupId>io.netty</groupId> Review comment: hmm, wonder why netty is required here though, I'll take a closer look. ########## File path: java/vector/src/main/java/org/apache/arrow/vector/compression/CompressionUtil.java ########## @@ -47,14 +57,21 @@ public static ArrowBodyCompression createBodyCompression(CompressionCodec codec) } /** - * Creates the {@link CompressionCodec} given the compression type. + * Process compression by compressing the buffer as is. */ - public static CompressionCodec createCodec(byte compressionType) { - switch (compressionType) { - case NoCompressionCodec.COMPRESSION_TYPE: - return NoCompressionCodec.INSTANCE; - default: - throw new IllegalArgumentException("Compression type not supported: " + compressionType); - } + public static ArrowBuf compressRawBuffer(BufferAllocator allocator, ArrowBuf inputBuffer) { + ArrowBuf compressedBuffer = allocator.buffer(SIZE_OF_UNCOMPRESSED_LENGTH + inputBuffer.writerIndex()); + compressedBuffer.setLong(0, NO_COMPRESSION_LENGTH); + compressedBuffer.setBytes(SIZE_OF_UNCOMPRESSED_LENGTH, inputBuffer, 0, inputBuffer.writerIndex()); + compressedBuffer.writerIndex(SIZE_OF_UNCOMPRESSED_LENGTH + inputBuffer.writerIndex()); + return compressedBuffer; + } + + /** + * Process decompression by decompressing the buffer as is. Review comment: please update the docs to match, something like. "Slice the buffer to contain the uncompressed bytes" ########## File path: java/compression/src/main/java/org/apache/arrow/compression/Lz4CompressionCodec.java ########## @@ -0,0 +1,159 @@ +/* + * Licensed to the Apache Software Foundation (ASF) under one or more + * contributor license agreements. See the NOTICE file distributed with + * this work for additional information regarding copyright ownership. + * The ASF 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 org.apache.arrow.compression; + +import java.io.ByteArrayInputStream; +import java.io.ByteArrayOutputStream; +import java.io.IOException; +import java.io.InputStream; +import java.io.OutputStream; + +import org.apache.arrow.flatbuf.CompressionType; +import org.apache.arrow.memory.ArrowBuf; +import org.apache.arrow.memory.BufferAllocator; +import org.apache.arrow.memory.util.MemoryUtil; +import org.apache.arrow.util.Preconditions; +import org.apache.arrow.vector.compression.CompressionCodec; +import org.apache.arrow.vector.compression.CompressionUtil; +import org.apache.commons.compress.compressors.lz4.FramedLZ4CompressorInputStream; +import org.apache.commons.compress.compressors.lz4.FramedLZ4CompressorOutputStream; +import org.apache.commons.compress.utils.IOUtils; + +import io.netty.util.internal.PlatformDependent; + +/** + * Compression codec for the LZ4 algorithm. + */ +public class Lz4CompressionCodec implements CompressionCodec { + + @Override + public ArrowBuf compress(BufferAllocator allocator, ArrowBuf uncompressedBuffer) { + Preconditions.checkArgument(uncompressedBuffer.writerIndex() <= Integer.MAX_VALUE, + "The uncompressed buffer size exceeds the integer limit"); + + if (uncompressedBuffer.writerIndex() == 0L) { + // shortcut for empty buffer + ArrowBuf compressedBuffer = allocator.buffer(CompressionUtil.SIZE_OF_UNCOMPRESSED_LENGTH); + compressedBuffer.setLong(0, 0); + compressedBuffer.writerIndex(CompressionUtil.SIZE_OF_UNCOMPRESSED_LENGTH); + uncompressedBuffer.close(); + return compressedBuffer; + } + + try { + ArrowBuf compressedBuffer = doCompress(allocator, uncompressedBuffer); + long compressedLength = compressedBuffer.writerIndex() - CompressionUtil.SIZE_OF_UNCOMPRESSED_LENGTH; + if (compressedLength > uncompressedBuffer.writerIndex()) { + // compressed buffer is larger, send the raw buffer + compressedBuffer.close(); + compressedBuffer = CompressionUtil.compressRawBuffer(allocator, uncompressedBuffer); + } + + uncompressedBuffer.close(); + return compressedBuffer; + } catch (IOException e) { + throw new RuntimeException(e); + } + } + + private ArrowBuf doCompress(BufferAllocator allocator, ArrowBuf uncompressedBuffer) throws IOException { + byte[] inBytes = new byte[(int) uncompressedBuffer.writerIndex()]; + PlatformDependent.copyMemory(uncompressedBuffer.memoryAddress(), inBytes, 0, uncompressedBuffer.writerIndex()); + ByteArrayOutputStream baos = new ByteArrayOutputStream(); + try (InputStream in = new ByteArrayInputStream(inBytes); + OutputStream out = new FramedLZ4CompressorOutputStream(baos)) { + IOUtils.copy(in, out); + } + + byte[] outBytes = baos.toByteArray(); + + ArrowBuf compressedBuffer = allocator.buffer(CompressionUtil.SIZE_OF_UNCOMPRESSED_LENGTH + outBytes.length); + + long uncompressedLength = uncompressedBuffer.writerIndex(); + if (!MemoryUtil.LITTLE_ENDIAN) { + uncompressedLength = Long.reverseBytes(uncompressedLength); + } + // first 8 bytes reserved for uncompressed length, to be consistent with the + // C++ implementation. + compressedBuffer.setLong(0, uncompressedLength); + + PlatformDependent.copyMemory( + outBytes, 0, compressedBuffer.memoryAddress() + CompressionUtil.SIZE_OF_UNCOMPRESSED_LENGTH, outBytes.length); + compressedBuffer.writerIndex(CompressionUtil.SIZE_OF_UNCOMPRESSED_LENGTH + outBytes.length); + return compressedBuffer; + } + + @Override + public ArrowBuf decompress(BufferAllocator allocator, ArrowBuf compressedBuffer) { + Preconditions.checkArgument(compressedBuffer.writerIndex() <= Integer.MAX_VALUE, + "The compressed buffer size exceeds the integer limit"); + + Preconditions.checkArgument(compressedBuffer.writerIndex() >= CompressionUtil.SIZE_OF_UNCOMPRESSED_LENGTH, + "Not enough data to decompress."); + + long decompressedLength = compressedBuffer.getLong(0); + if (!MemoryUtil.LITTLE_ENDIAN) { + decompressedLength = Long.reverseBytes(decompressedLength); + } + + if (decompressedLength == 0L) { + // shortcut for empty buffer + compressedBuffer.close(); + return allocator.getEmpty(); + } + + if (decompressedLength == CompressionUtil.NO_COMPRESSION_LENGTH) { + // no compression + return CompressionUtil.decompressRawBuffer(compressedBuffer); + } + + try { + ArrowBuf decompressedBuffer = doDecompress(allocator, compressedBuffer); + compressedBuffer.close(); + return decompressedBuffer; + } catch (IOException e) { + throw new RuntimeException(e); + } + } + + private ArrowBuf doDecompress(BufferAllocator allocator, ArrowBuf compressedBuffer) throws IOException { + long decompressedLength = compressedBuffer.getLong(0); + if (!MemoryUtil.LITTLE_ENDIAN) { + decompressedLength = Long.reverseBytes(decompressedLength); + } + + byte[] inBytes = new byte[(int) (compressedBuffer.writerIndex() - CompressionUtil.SIZE_OF_UNCOMPRESSED_LENGTH)]; + PlatformDependent.copyMemory( + compressedBuffer.memoryAddress() + CompressionUtil.SIZE_OF_UNCOMPRESSED_LENGTH, inBytes, 0, inBytes.length); + ByteArrayOutputStream out = new ByteArrayOutputStream((int) decompressedLength); + try (InputStream in = new FramedLZ4CompressorInputStream(new ByteArrayInputStream(inBytes))) { + IOUtils.copy(in, out); + } + + byte[] outBytes = out.toByteArray(); + ArrowBuf decompressedBuffer = allocator.buffer(outBytes.length); + PlatformDependent.copyMemory(outBytes, 0, decompressedBuffer.memoryAddress(), outBytes.length); + decompressedBuffer.writerIndex(decompressedLength); + return decompressedBuffer; + } + + @Override + public String getCodecName() { + return CompressionType.name(CompressionType.LZ4_FRAME); Review comment: With the new enum, maybe we can make this an accessor that returns and enum instead? and then the byte can be extracted from there where necesssary? ---------------------------------------------------------------- This is an automated message from the Apache Git Service. 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