vvysotskyi commented on a change in pull request #2321: URL: https://github.com/apache/drill/pull/2321#discussion_r717798313
########## File path: exec/java-exec/src/main/java/org/apache/drill/exec/store/parquet/compression/DrillCompressionCodecFactory.java ########## @@ -0,0 +1,117 @@ +/* + * 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.drill.exec.store.parquet.compression; + +import java.util.Arrays; +import java.util.HashMap; +import java.util.HashSet; +import java.util.Map; +import java.util.Set; + +import org.apache.hadoop.conf.Configuration; +import org.apache.parquet.bytes.ByteBufferAllocator; +import org.apache.parquet.compression.CompressionCodecFactory; +import org.apache.parquet.hadoop.CodecFactory; +import org.apache.parquet.hadoop.metadata.CompressionCodecName; +import org.slf4j.Logger; +import org.slf4j.LoggerFactory; + +/** + * A delegating compression codec factory that returns (de)compressors based on + * https://github.com/airlift/aircompressor when possible and falls back to + * parquet-mr otherwise. The aircompressor lib was introduced into Drill + * because of difficulties encountered with the JNI-based implementations of + * lzo, lz4 and zstd in parquet-mr. + * + * By modifying the constant AIRCOMPRESSOR_CODECS it is possible to choose + * which codecs should be routed to which lib. In addition, this class + * implements parquet-mr's CompressionCodecFactory interface meaning that + * swapping this factory for e.g. one in parquet-mr will have minimal impact + * on code in Drill relying on a CompressCodecFactory. + * + */ +public class DrillCompressionCodecFactory implements CompressionCodecFactory { + private static final Logger logger = LoggerFactory.getLogger(DrillCompressionCodecFactory.class); + + // The set of codecs to be handled by aircompressor + private static final Set<CompressionCodecName> AIRCOMPRESSOR_CODECS = new HashSet<>( + Arrays.asList(CompressionCodecName.LZ4, CompressionCodecName.LZO, + CompressionCodecName.SNAPPY, CompressionCodecName.ZSTD)); + + // pool of reused aircompressor compressors (parquet-mr's factory has its own) + private final Map airCompressors = new HashMap(); Review comment: If `AirliftBytesInputCompressor` is specified, no cast is required. -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected]
