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 * @author Jens Wilke; created: 2014-03-27
027 */
028public interface StorageEntry {
029
030  /** Key of the stored entry */
031  Object getKey();
032
033  /** Value of the stored entry */
034  Object getValueOrException();
035
036  /** Time the entry was last fetched or created from the original source */
037  long getCreatedOrUpdated();
038
039  /**
040   * Time when the value is expired and is not allowed to be returned any more.
041   * The storage needs to store this value. The storage may purge entries with
042   * the time exceeded. Returns 0 if not used, no expiry is requested.
043   */
044  long getValueExpiryTime();
045
046  /**
047   * Expiry time of the storage entry. After reaching this time, the entry should
048   * be purged by the storage. The entry expiry time will get updated by
049   * the the cache when the value is not expired and the entry is still
050   * accessed. Returns 0 if not used.
051   */
052  long getEntryExpiryTime();
053
054}