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.proxy;
018
019import org.apache.commons.pool2.ObjectPool;
020import org.apache.commons.pool2.UsageTracking;
021
022/**
023 * Create a new object pool where the pooled objects are wrapped in proxies
024 * allowing better control of pooled objects and in particular the prevention
025 * of the continued use of an object by a client after that client returns the
026 * object to the pool.
027 *
028 * @param <T> type of the pooled object
029 * @since 2.0
030 */
031public class ProxiedObjectPool<T> implements ObjectPool<T> {
032
033    private final ObjectPool<T> pool;
034    private final ProxySource<T> proxySource;
035
036    /**
037     * Constructs a new proxied object pool.
038     *
039     * @param pool  The object pool to wrap
040     * @param proxySource The source of the proxy objects
041     */
042    public ProxiedObjectPool(final ObjectPool<T> pool, final ProxySource<T> proxySource) {
043        this.pool = pool;
044        this.proxySource = proxySource;
045    }
046
047    @Override
048    public void addObject() throws Exception {
049        pool.addObject();
050    }
051
052    @SuppressWarnings("unchecked")
053    @Override
054    public T borrowObject() throws Exception {
055        UsageTracking<T> usageTracking = null;
056        if (pool instanceof UsageTracking) {
057            usageTracking = (UsageTracking<T>) pool;
058        }
059        return proxySource.createProxy(pool.borrowObject(), usageTracking);
060    }
061
062    @Override
063    public void clear() throws Exception {
064        pool.clear();
065    }
066
067    @Override
068    public void close() {
069        pool.close();
070    }
071
072    @Override
073    public int getNumActive() {
074        return pool.getNumActive();
075    }
076
077    @Override
078    public int getNumIdle() {
079        return pool.getNumIdle();
080    }
081
082    @Override
083    public void invalidateObject(final T proxy) throws Exception {
084        pool.invalidateObject(proxySource.resolveProxy(proxy));
085    }
086
087    @Override
088    public void returnObject(final T proxy) throws Exception {
089        pool.returnObject(proxySource.resolveProxy(proxy));
090    }
091
092    /**
093     * @since 2.4.3
094     */
095    @Override
096    public String toString() {
097        final StringBuilder builder = new StringBuilder();
098        builder.append("ProxiedObjectPool [pool=");
099        builder.append(pool);
100        builder.append(", proxySource=");
101        builder.append(proxySource);
102        builder.append("]");
103        return builder.toString();
104    }
105}