    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 */
    017package org.apache.commons.pool2;
    018
    019/**
    020 * A base implementation of {@code PoolableObjectFactory}.
    021 * <p>
    022 * All operations defined here are essentially no-op's.
    023 * <p>
    024 * This class is immutable, and therefore thread-safe
    025 *
    026 * @param <T> Type of element managed in this factory.
    027 *
    028 * @see PooledObjectFactory
    029 * @see BaseKeyedPooledObjectFactory
    030 *
    031 * @since 2.0
    032 */
    033public abstract class BasePooledObjectFactory<T> extends BaseObject implements PooledObjectFactory<T> {
    034    /**
    035     * Creates an object instance, to be wrapped in a {@link PooledObject}.
    036     * <p>This method <strong>must</strong> support concurrent, multi-threaded
    037     * activation.</p>
    038     *
    039     * @return an instance to be served by the pool
    040     *
    041     * @throws Exception if there is a problem creating a new instance,
    042     *    this will be propagated to the code requesting an object.
    043     */
    044    public abstract T create() throws Exception;
    045
    046    /**
    047     * Wrap the provided instance with an implementation of
    048     * {@link PooledObject}.
    049     *
    050     * @param obj the instance to wrap
    051     *
    052     * @return The provided instance, wrapped by a {@link PooledObject}
    053     */
    054    public abstract PooledObject<T> wrap(T obj);
    055
    056    @Override
    057    public PooledObject<T> makeObject() throws Exception {
    058        return wrap(create());
    059    }
    060
    061    /**
    062     *  No-op.
    063     *
    064     *  @param p ignored
    065     */
    066    @Override
    067    public void destroyObject(final PooledObject<T> p)
    068        throws Exception  {
    069        // The default implementation is a no-op.
    070    }
    071
    072    /**
    073     * This implementation always returns {@code true}.
    074     *
    075     * @param p ignored
    076     *
    077     * @return {@code true}
    078     */
    079    @Override
    080    public boolean validateObject(final PooledObject<T> p) {
    081        return true;
    082    }
    083
    084    /**
    085     *  No-op.
    086     *
    087     *  @param p ignored
    088     */
    089    @Override
    090    public void activateObject(final PooledObject<T> p) throws Exception {
    091        // The default implementation is a no-op.
    092    }
    093
    094    /**
    095     *  No-op.
    096     *
    097     * @param p ignored
    098     */
    099    @Override
    100    public void passivateObject(final PooledObject<T> p)
    101        throws Exception {
    102        // The default implementation is a no-op.
    103    }
    104}