001    /**
002     * JDBM LICENSE v1.00
003     *
004     * Redistribution and use of this software and associated documentation
005     * ("Software"), with or without modification, are permitted provided
006     * that the following conditions are met:
007     *
008     * 1. Redistributions of source code must retain copyright
009     *    statements and notices.  Redistributions must also contain a
010     *    copy of this document.
011     *
012     * 2. Redistributions in binary form must reproduce the
013     *    above copyright notice, this list of conditions and the
014     *    following disclaimer in the documentation and/or other
015     *    materials provided with the distribution.
016     *
017     * 3. The name "JDBM" must not be used to endorse or promote
018     *    products derived from this Software without prior written
019     *    permission of Cees de Groot.  For written permission,
020     *    please contact cg@cdegroot.com.
021     *
022     * 4. Products derived from this Software may not be called "JDBM"
023     *    nor may "JDBM" appear in their names without prior written
024     *    permission of Cees de Groot.
025     *
026     * 5. Due credit should be given to the JDBM Project
027     *    (http://jdbm.sourceforge.net/).
028     *
029     * THIS SOFTWARE IS PROVIDED BY THE JDBM PROJECT AND CONTRIBUTORS
030     * ``AS IS'' AND ANY EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT
031     * NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
032     * FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL
033     * CEES DE GROOT OR ANY CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
034     * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
035     * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
036     * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
037     * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
038     * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
039     * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
040     * OF THE POSSIBILITY OF SUCH DAMAGE.
041     *
042     * Copyright 2000 (C) Cees de Groot. All Rights Reserved.
043     * Contributions are Copyright (C) 2000 by their associated contributors.
044     *
045     * $Id: CachePolicyListener.java,v 1.3 2003/11/01 13:25:41 dranatunga Exp $
046     */
047    
048    package jdbm.helper;
049    
050    /**
051     * Callback interface between {@link CachePolicy} and a Cache implementation
052     * to notify about cached object eviction.
053     * <p>
054     * Note that <code>CachePolicy</code> implementations typically use
055     * <em>object equality</em> when removing listeners, so concrete
056     * implementations of this interface should also pay attention to
057     * their {@link Object#equals(Object)} and {@link Object#hashCode()}
058     * methods.
059     *
060     * @author <a href="mailto:boisvert@intalio.com">Alex Boisvert</a>
061     * @version $Id: CachePolicyListener.java,v 1.3 2003/11/01 13:25:41 dranatunga Exp $
062     */
063    public interface CachePolicyListener {
064    
065        /**
066         * Notification that the cache this listener is attached to is evicting
067         * the object indicated.
068         *
069         * @param obj object being evited from cache
070         * @throws CacheEvictionException if this listener encountered problems
071         *     while preparing for the specified object's eviction. For example,
072         *     a listener may try to persist the object to disk, and encounter
073         *     an <code>IOException</code>.
074         */
075        public void cacheObjectEvicted(Object obj) throws CacheEvictionException;
076    
077    }