001/**
002 * Licensed to the Apache Software Foundation (ASF) under one
003 * or more contributor license agreements.  See the NOTICE file
004 * distributed with this work for additional information
005 * regarding copyright ownership.  The ASF licenses this file
006 * to you under the Apache License, Version 2.0 (the
007 * "License"); you may not use this file except in compliance
008 * with the License.  You may obtain a copy of the License at
009 *
010 *     http://www.apache.org/licenses/LICENSE-2.0
011 *
012 * Unless required by applicable law or agreed to in writing, software
013 * distributed under the License is distributed on an "AS IS" BASIS,
014 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
015 * See the License for the specific language governing permissions and
016 * limitations under the License.
017 */
018package org.apache.hadoop.hdfs.server.datanode.fsdataset;
019
020import java.io.Closeable;
021import java.io.FileOutputStream;
022import java.io.OutputStream;
023import java.io.IOException;
024
025import org.apache.hadoop.io.IOUtils;
026import org.apache.hadoop.util.DataChecksum;
027
028/**
029 * Contains the output streams for the data and checksum of a replica.
030 */
031public class ReplicaOutputStreams implements Closeable {
032  private final OutputStream dataOut;
033  private final OutputStream checksumOut;
034  private final DataChecksum checksum;
035
036  /**
037   * Create an object with a data output stream, a checksum output stream
038   * and a checksum.
039   */
040  public ReplicaOutputStreams(OutputStream dataOut, OutputStream checksumOut,
041      DataChecksum checksum) {
042    this.dataOut = dataOut;
043    this.checksumOut = checksumOut;
044    this.checksum = checksum;
045  }
046
047  /** @return the data output stream. */
048  public OutputStream getDataOut() {
049    return dataOut;
050  }
051
052  /** @return the checksum output stream. */
053  public OutputStream getChecksumOut() {
054    return checksumOut;
055  }
056
057  /** @return the checksum. */
058  public DataChecksum getChecksum() {
059    return checksum;
060  }
061
062  @Override
063  public void close() {
064    IOUtils.closeStream(dataOut);
065    IOUtils.closeStream(checksumOut);
066  }
067
068  /**
069   * Sync the data stream if it supports it.
070   */
071  public void syncDataOut() throws IOException {
072    if (dataOut instanceof FileOutputStream) {
073      ((FileOutputStream)dataOut).getChannel().force(true);
074    }
075  }
076  
077  /**
078   * Sync the checksum stream if it supports it.
079   */
080  public void syncChecksumOut() throws IOException {
081    if (checksumOut instanceof FileOutputStream) {
082      ((FileOutputStream)checksumOut).getChannel().force(true);
083    }
084  }
085
086}