001    /*
002     * Licensed to the Apache Software Foundation (ASF) under one or more
003     * contributor license agreements.  See the NOTICE file distributed with
004     * this work for additional information regarding copyright ownership.
005     * The ASF licenses this file to You under the Apache License, Version 2.0
006     * (the "License"); you may not use this file except in compliance with
007     * the License.  You may obtain a copy of the License at
008     *
009     *      http://www.apache.org/licenses/LICENSE-2.0
010     *
011     * Unless required by applicable law or agreed to in writing, software
012     * distributed under the License is distributed on an "AS IS" BASIS,
013     * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014     * See the License for the specific language governing permissions and
015     * limitations under the License.
016     */
017    
018    package org.apache.commons.pool;
019    
020    /**
021     * A base implementation of <code>KeyedPoolableObjectFactory</code>.
022     * <p>
023     * All operations defined here are essentially no-op's.
024     * </p>
025     *
026     * @param <K> the type of keys in this pool
027     * @param <V> the type of objects held in this pool
028     * 
029     * @see KeyedPoolableObjectFactory
030     *
031     * @author Rodney Waldhoff
032     * @version $Revision: 1222388 $ $Date: 2011-12-22 13:28:27 -0500 (Thu, 22 Dec 2011) $
033     * @since Pool 1.0
034     */
035    public abstract class BaseKeyedPoolableObjectFactory<K, V> implements KeyedPoolableObjectFactory<K, V> {
036        /**
037         * Create an instance that can be served by the pool.
038         *
039         * @param key the key used when constructing the object
040         * @return an instance that can be served by the pool
041         */
042        public abstract V makeObject(K key)
043            throws Exception;
044    
045        /**
046         * Destroy an instance no longer needed by the pool.
047         * <p>
048         * The default implementation is a no-op.
049         * </p>
050         *
051         * @param key the key used when selecting the instance
052         * @param obj the instance to be destroyed
053         */
054        public void destroyObject(K key, V obj)
055            throws Exception {
056        }
057    
058        /**
059         * Ensures that the instance is safe to be returned by the pool.
060         * <p>
061         * The default implementation always returns <tt>true</tt>.
062         * </p>
063         *
064         * @param key the key used when selecting the object
065         * @param obj the instance to be validated
066         * @return always <code>true</code> in the default implementation
067         */ 
068        public boolean validateObject(K key, V obj) {
069            return true;
070        }
071    
072        /**
073         * Reinitialize an instance to be returned by the pool.
074         * <p>
075         * The default implementation is a no-op.
076         * </p>
077         *
078         * @param key the key used when selecting the object
079         * @param obj the instance to be activated
080         */
081        public void activateObject(K key, V obj)
082            throws Exception {
083        }
084    
085        /**
086         * Uninitialize an instance to be returned to the idle object pool.
087         * <p>
088         * The default implementation is a no-op.
089         * </p>
090         *
091         * @param key the key used when selecting the object
092         * @param obj the instance to be passivated
093         */
094        public void passivateObject(K key, V obj)
095            throws Exception {
096        }
097    }