001package org.cache2k.storage;
002
003/*
004 * #%L
005 * cache2k core package
006 * %%
007 * Copyright (C) 2000 - 2015 headissue GmbH, Munich
008 * %%
009 * This program is free software: you can redistribute it and/or modify
010 * it under the terms of the GNU General Public License as
011 * published by the Free Software Foundation, either version 3 of the 
012 * License, or (at your option) any later version.
013 * 
014 * This program is distributed in the hope that it will be useful,
015 * but WITHOUT ANY WARRANTY; without even the implied warranty of
016 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
017 * GNU General Public License for more details.
018 * 
019 * You should have received a copy of the GNU General Public 
020 * License along with this program.  If not, see
021 * <http://www.gnu.org/licenses/gpl-3.0.html>.
022 * #L%
023 */
024
025/**
026 * Optional interface for a {@link CacheStorage} if the storage needs to flush any
027 * unwritten data to make it persistent.
028 *
029 * @author Jens Wilke; created: 2014-06-09
030 */
031public interface FlushableStorage extends CacheStorage {
032
033  /**
034   * Flush any unwritten information to disk. The method returns when the flush
035   * is finished and everything is written. The cache is not protecting the
036   * storage from concurrent read/write operation while the flush is performed.
037   *
038   * <p/>A flush is initiated by client request or on regular intervals after a
039   * modification has happened.
040   */
041  public void flush(FlushableStorage.FlushContext ctx, long now) throws Exception;
042
043  interface FlushContext extends CacheStorage.MultiThreadedContext {
044
045  }
046
047}