| /* |
| * 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.iotdb.tsfile.write.writer.tsmiterator; |
| |
| import org.apache.iotdb.tsfile.file.metadata.ChunkGroupMetadata; |
| import org.apache.iotdb.tsfile.file.metadata.ChunkMetadata; |
| import org.apache.iotdb.tsfile.file.metadata.IChunkMetadata; |
| import org.apache.iotdb.tsfile.file.metadata.TimeseriesMetadata; |
| import org.apache.iotdb.tsfile.file.metadata.enums.TSDataType; |
| import org.apache.iotdb.tsfile.read.common.Path; |
| import org.apache.iotdb.tsfile.read.reader.LocalTsFileInput; |
| import org.apache.iotdb.tsfile.utils.Pair; |
| import org.apache.iotdb.tsfile.utils.ReadWriteIOUtils; |
| |
| import org.slf4j.Logger; |
| import org.slf4j.LoggerFactory; |
| |
| import java.io.File; |
| import java.io.IOException; |
| import java.nio.ByteBuffer; |
| import java.util.ArrayList; |
| import java.util.LinkedList; |
| import java.util.List; |
| |
| /** |
| * This class read ChunkMetadata iteratively from disk(.cmt file) and memory(list of |
| * ChunkGroupMetadata), and construct them as TimeseriesMetadata. It will read ChunkMetadata in disk |
| * first, and after all ChunkMetadata in disk is read, it will read ChunkMetadata in memory. |
| */ |
| public class DiskTSMIterator extends TSMIterator { |
| |
| private static final Logger LOG = LoggerFactory.getLogger(DiskTSMIterator.class); |
| |
| private LinkedList<Long> endPosForEachDevice; |
| private File cmtFile; |
| private LocalTsFileInput input; |
| private long fileLength = 0; |
| private long currentPos = 0; |
| private long nextEndPosForDevice = 0; |
| private String currentDevice; |
| private boolean remainsInFile = true; |
| |
| protected DiskTSMIterator( |
| File cmtFile, |
| List<ChunkGroupMetadata> chunkGroupMetadataList, |
| LinkedList<Long> endPosForEachDevice) |
| throws IOException { |
| super(chunkGroupMetadataList); |
| this.cmtFile = cmtFile; |
| this.endPosForEachDevice = endPosForEachDevice; |
| this.input = new LocalTsFileInput(cmtFile.toPath()); |
| this.fileLength = cmtFile.length(); |
| this.nextEndPosForDevice = endPosForEachDevice.removeFirst(); |
| } |
| |
| @Override |
| public boolean hasNext() { |
| return remainsInFile || iterator.hasNext(); |
| } |
| |
| @Override |
| public Pair<Path, TimeseriesMetadata> next() { |
| try { |
| if (remainsInFile) { |
| // deserialize from file |
| return getTimeSerisMetadataFromFile(); |
| } else { |
| // get from memory iterator |
| return super.next(); |
| } |
| } catch (IOException e) { |
| LOG.error("Meets IOException when reading timeseries metadata from disk", e); |
| return null; |
| } |
| } |
| |
| private Pair<Path, TimeseriesMetadata> getTimeSerisMetadataFromFile() throws IOException { |
| if (currentPos == nextEndPosForDevice) { |
| // deserialize the current device name |
| currentDevice = ReadWriteIOUtils.readString(input.wrapAsInputStream()); |
| nextEndPosForDevice = |
| endPosForEachDevice.size() > 0 ? endPosForEachDevice.removeFirst() : fileLength; |
| } |
| // deserialize public info for measurement |
| String measurementUid = ReadWriteIOUtils.readVarIntString(input.wrapAsInputStream()); |
| byte dataTypeInByte = ReadWriteIOUtils.readByte(input.wrapAsInputStream()); |
| TSDataType dataType = TSDataType.getTsDataType(dataTypeInByte); |
| int chunkBufferSize = ReadWriteIOUtils.readInt(input.wrapAsInputStream()); |
| ByteBuffer chunkBuffer = ByteBuffer.allocate(chunkBufferSize); |
| int readSize = ReadWriteIOUtils.readAsPossible(input, chunkBuffer); |
| if (readSize < chunkBufferSize) { |
| throw new IOException( |
| String.format( |
| "Expected to read %s bytes, but actually read %s bytes", chunkBufferSize, readSize)); |
| } |
| chunkBuffer.flip(); |
| |
| // deserialize chunk metadata from chunk buffer |
| List<IChunkMetadata> chunkMetadataList = new ArrayList<>(); |
| while (chunkBuffer.hasRemaining()) { |
| chunkMetadataList.add(ChunkMetadata.deserializeFrom(chunkBuffer, dataType)); |
| } |
| updateCurrentPos(); |
| return new Pair<>( |
| new Path(currentDevice, measurementUid, false), |
| constructOneTimeseriesMetadata(measurementUid, chunkMetadataList)); |
| } |
| |
| private void updateCurrentPos() throws IOException { |
| currentPos = input.position(); |
| if (currentPos >= fileLength) { |
| remainsInFile = false; |
| input.close(); |
| } |
| } |
| } |