trimmingcache.java

Java的面向对象数据库系统的源代码

// You can redistribute this software and/or modify it under the terms of
// the Ozone Core License version 1 published by ozone-db.org.
//
// Copyright (C) 2003-@year@, Leo Mekenkamp. All rights reserved.
//
// $Id: TrimmingCache.java,v 1.1.2.1 2004/03/28 16:40:04 per_nyfelt Exp $

package org.ozoneDB.core.storage;


/**
 * A trimming cache is a cache that calls a TrimHandler when it 'knows' that
 * it has thrown an element out of the cache.
 * 
 * @author <a href="mailto:leoATmekenkampD0Tcom">Leo Mekenkamp (mind the anti sp@m)</a>
 * @version $Id: TrimmingCache.java,v 1.1.2.1 2004/03/28 16:40:04 per_nyfelt Exp $
 */
public interface TrimmingCache extends Cache {
    
    /**
     * Used by a <code>Cache</code> to provide for a meganism to handle elements
     * that are going to be thrown out of that cache.
     */
    public interface TrimHandler {
        
        /**
         * Called by a <code>TrimmingCache</code> just before an element will be
         * removed from that cache.
         * This method may be called asynchronously (by different threads)
         * depending on the implementation.
         */
        public void trimming(Object key, Object value);
        
    }
    
    public void setTrimHandler(TrimHandler trimHandler);
    
    public TrimHandler getTrimHandler();
 
    public void setSynchronizer(Object synchronizer);

    public Object getSynchronizer();
}