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 */
018
019package org.apache.hadoop.fs;
020
021import java.io.IOException;
022
023import org.apache.hadoop.classification.InterfaceAudience;
024import org.apache.hadoop.classification.InterfaceStability;
025
026/** This interface for flush/sync operation. */
027@InterfaceAudience.Public
028@InterfaceStability.Evolving
029public interface Syncable {
030  /**
031   * @deprecated As of HADOOP 0.21.0, replaced by hflush
032   * @see #hflush()
033   */
034  @Deprecated  public void sync() throws IOException;
035  
036  /** Flush out the data in client's user buffer. After the return of
037   * this call, new readers will see the data.
038   * @throws IOException if any error occurs
039   */
040  public void hflush() throws IOException;
041  
042  /** Similar to posix fsync, flush out the data in client's user buffer 
043   * all the way to the disk device (but the disk may have it in its cache).
044   * @throws IOException if error occurs
045   */
046  public void hsync() throws IOException;
047}