| /* |
| * 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.jackrabbit.oak.segment.remote; |
| |
| import static org.apache.jackrabbit.oak.segment.remote.RemoteUtilities.getSegmentFileName; |
| import static org.apache.jackrabbit.oak.segment.remote.RemoteUtilities.OFF_HEAP; |
| |
| import com.google.common.base.Stopwatch; |
| |
| import org.apache.jackrabbit.oak.commons.Buffer; |
| import org.apache.jackrabbit.oak.segment.spi.monitor.IOMonitor; |
| import org.apache.jackrabbit.oak.segment.spi.persistence.SegmentArchiveEntry; |
| import org.apache.jackrabbit.oak.segment.spi.persistence.SegmentArchiveReader; |
| |
| import java.io.File; |
| import java.io.IOException; |
| import java.util.ArrayList; |
| import java.util.LinkedHashMap; |
| import java.util.List; |
| import java.util.Map; |
| import java.util.UUID; |
| import java.util.concurrent.TimeUnit; |
| |
| public abstract class AbstractRemoteSegmentArchiveReader implements SegmentArchiveReader { |
| protected final IOMonitor ioMonitor; |
| |
| protected final Map<UUID, RemoteSegmentArchiveEntry> index = new LinkedHashMap<>(); |
| |
| protected Boolean hasGraph; |
| |
| public AbstractRemoteSegmentArchiveReader(IOMonitor ioMonitor) throws IOException { |
| this.ioMonitor = ioMonitor; |
| } |
| |
| @Override |
| public Buffer readSegment(long msb, long lsb) throws IOException { |
| RemoteSegmentArchiveEntry indexEntry = index.get(new UUID(msb, lsb)); |
| if (indexEntry == null) { |
| return null; |
| } |
| |
| Buffer buffer; |
| if (OFF_HEAP) { |
| buffer = Buffer.allocateDirect(indexEntry.getLength()); |
| } else { |
| buffer = Buffer.allocate(indexEntry.getLength()); |
| } |
| ioMonitor.beforeSegmentRead(archivePathAsFile(), msb, lsb, indexEntry.getLength()); |
| Stopwatch stopwatch = Stopwatch.createStarted(); |
| String segmentFileName = getSegmentFileName(indexEntry); |
| doReadSegmentToBuffer(segmentFileName, buffer); |
| long elapsed = stopwatch.elapsed(TimeUnit.NANOSECONDS); |
| ioMonitor.afterSegmentRead(archivePathAsFile(), msb, lsb, indexEntry.getLength(), elapsed); |
| return buffer; |
| } |
| |
| @Override |
| public boolean containsSegment(long msb, long lsb) { |
| return index.containsKey(new UUID(msb, lsb)); |
| } |
| |
| @Override |
| public List<SegmentArchiveEntry> listSegments() { |
| return new ArrayList<>(index.values()); |
| } |
| |
| @Override |
| public Buffer getGraph() throws IOException { |
| Buffer graph = doReadDataFile(".gph"); |
| hasGraph = graph != null; |
| return graph; |
| } |
| |
| @Override |
| public boolean hasGraph() { |
| if (hasGraph == null) { |
| try { |
| getGraph(); |
| } catch (IOException ignore) { } |
| } |
| return hasGraph != null ? hasGraph : false; |
| } |
| |
| @Override |
| public Buffer getBinaryReferences() throws IOException { |
| return doReadDataFile(".brf"); |
| } |
| |
| @Override |
| public void close() { |
| // do nothing |
| } |
| |
| @Override |
| public int getEntrySize(int size) { |
| return size; |
| } |
| |
| /** |
| * Populates the archive index, summing up each entry's length. |
| * @return length, the total length of the archive |
| */ |
| protected abstract long computeArchiveIndexAndLength() throws IOException; |
| |
| /** |
| * Reads the segment from the remote storage. |
| * @param segmentFileName, the name of the segment (msb + lsb) prefixed by its position in the archive |
| * @param buffer, the buffer to which to read |
| */ |
| protected abstract void doReadSegmentToBuffer(String segmentFileName, Buffer buffer) throws IOException; |
| |
| /** |
| * Reads a data file inside the archive. This entry is not a segment. Its full name is given by archive name + extension. |
| * @param extension, extension of the file |
| * @return the buffer containing the data file bytes |
| */ |
| protected abstract Buffer doReadDataFile(String extension) throws IOException; |
| |
| /** |
| * Returns the decoded file component of this archive. |
| * @return the decoded file component of this archive. |
| */ |
| protected abstract File archivePathAsFile(); |
| } |