001    /*
002     * JBoss DNA (http://www.jboss.org/dna)
003     * See the COPYRIGHT.txt file distributed with this work for information
004     * regarding copyright ownership.  Some portions may be licensed
005     * to Red Hat, Inc. under one or more contributor license agreements.
006     * See the AUTHORS.txt file in the distribution for a full listing of 
007     * individual contributors. 
008     *
009     * JBoss DNA is free software. Unless otherwise indicated, all code in JBoss DNA
010     * is licensed to you under the terms of the GNU Lesser General Public License as
011     * published by the Free Software Foundation; either version 2.1 of
012     * the License, or (at your option) any later version.
013     *
014     * JBoss DNA 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 GNU
017     * Lesser General Public License for more details.
018     *
019     * You should have received a copy of the GNU Lesser General Public
020     * License along with this software; if not, write to the Free
021     * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
022     * 02110-1301 USA, or see the FSF site: http://www.fsf.org.
023     */
024    package org.jboss.dna.graph.cache;
025    
026    import java.io.Serializable;
027    import org.jboss.dna.graph.property.DateTime;
028    
029    /**
030     * Interface defining an object that can be cached according to a {@link CachePolicy}.
031     * 
032     * @author Randall Hauch
033     */
034    public interface Cacheable extends Serializable {
035    
036        /**
037         * Get the time that this node data was originally loaded.
038         * 
039         * @return the system time (in milliseconds) that the node data was loaded
040         */
041        DateTime getTimeLoaded();
042    
043        /**
044         * Get the caching policy to be used for this object.
045         * <p>
046         * Note that the values of the policy are relative to the {@link #getTimeLoaded() time the node was loaded}, so the same
047         * instance can be used for many nodes.
048         * </p>
049         * 
050         * @return cachePolicy the caching policy, which may not be null
051         */
052        public CachePolicy getCachePolicy();
053    
054        /**
055         * Set the caching policy for this object.
056         * 
057         * @param cachePolicy the caching policy to use for this object
058         * @throws IllegalArgumentException if the cachePolicy is null
059         */
060        public void setCachePolicy( CachePolicy cachePolicy );
061    
062    }