zhijiangW commented on a change in pull request #13595: URL: https://github.com/apache/flink/pull/13595#discussion_r510816451
########## File path: flink-runtime/src/main/java/org/apache/flink/runtime/io/network/partition/PartitionedFile.java ########## @@ -0,0 +1,139 @@ +/* + * 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.flink.runtime.io.network.partition; + +import org.apache.flink.util.IOUtils; + +import java.io.IOException; +import java.nio.ByteBuffer; +import java.nio.ByteOrder; +import java.nio.channels.FileChannel; +import java.nio.file.Path; + +import static org.apache.flink.util.Preconditions.checkArgument; +import static org.apache.flink.util.Preconditions.checkNotNull; + +/** + * {@link PartitionedFile} is the persistent file type of sort-merge blocking shuffle. Each {@link PartitionedFile} + * contains two files: one is data file and the other is index file. Both the data file and index file have multiple + * regions. Each data region store the shuffle data in subpartition index order and the corresponding index region + * contains index entries of all subpartitions. Each index entry is a (long, integer) tuple of which the long value + * is the file offset of the corresponding subpartition and the integer value is the number of buffers. + */ +public class PartitionedFile { + + public static final String DATA_FILE_SUFFIX = ".shuffle.data"; + + public static final String INDEX_FILE_SUFFIX = ".shuffle.index"; + + public static final ByteOrder DEFAULT_BYTE_ORDER = ByteOrder.BIG_ENDIAN; + + /** Size of each index entry in the index file. 8 bytes for offset and 4 bytes for number of buffers. */ + public static final int INDEX_ENTRY_SIZE = 8 + 4; + + /** Number of data regions in this {@link PartitionedFile}. */ + private final int numRegions; + + /** Number of subpartitions of this {@link PartitionedFile}. */ + private final int numSubpartitions; + + /** Path of the data file which stores all data in this {@link PartitionedFile}. */ + private final Path dataFilePath; + + /** Path of the index file which stores indexes of all regions in this {@link PartitionedFile}. */ + private final Path indexFilePath; + + /** Used to accelerate index data access. */ + private final ByteBuffer indexDataCache; Review comment: nit: better to add annotation `@Nullable`, also for the respective constructor argument. ---------------------------------------------------------------- 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. For queries about this service, please contact Infrastructure at: [email protected]
