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.hbase.io.asyncfs;
019
020import java.io.Closeable;
021import java.io.IOException;
022import java.nio.ByteBuffer;
023import java.util.concurrent.CompletableFuture;
024
025import org.apache.yetus.audience.InterfaceAudience;
026import org.apache.hadoop.hbase.util.CancelableProgressable;
027import org.apache.hadoop.hdfs.protocol.DatanodeInfo;
028
029/**
030 * Interface for asynchronous filesystem output stream.
031 * <p>
032 * The implementation is not required to be thread safe.
033 */
034@InterfaceAudience.Private
035public interface AsyncFSOutput extends Closeable {
036
037  /**
038   * Just call write(b, 0, b.length).
039   * @see #write(byte[], int, int)
040   */
041  void write(byte[] b);
042
043  /**
044   * Copy the data into the buffer. Note that you need to call {@link #flush(boolean)} to flush the
045   * buffer manually.
046   */
047  void write(byte[] b, int off, int len);
048
049  /**
050   * Write an int to the buffer.
051   */
052  void writeInt(int i);
053
054  /**
055   * Copy the data in the given {@code bb} into the buffer.
056   */
057  void write(ByteBuffer bb);
058
059  /**
060   * Return the current size of buffered data.
061   */
062  int buffered();
063
064  /**
065   * Whether the stream is broken.
066   */
067  boolean isBroken();
068
069  /**
070   * Return current pipeline. Empty array if no pipeline.
071   */
072  DatanodeInfo[] getPipeline();
073
074  /**
075   * Flush the buffer out.
076   * @param sync persistent the data to device
077   * @return A CompletableFuture that hold the acked length after flushing.
078   */
079  CompletableFuture<Long> flush(boolean sync);
080
081  /**
082   * The close method when error occurred.
083   */
084  void recoverAndClose(CancelableProgressable reporter) throws IOException;
085
086  /**
087   * Close the file. You should call {@link #recoverAndClose(CancelableProgressable)} if this method
088   * throws an exception.
089   */
090  @Override
091  void close() throws IOException;
092}