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 java.lang.reflect.Proxy;
020import java.util.Arrays;
021
022import org.apache.commons.pool2.UsageTracking;
023
024/**
025 * Provides proxy objects using Java reflection.
026 *
027 * @param <T> type of the pooled object to be proxied
028 *
029 * @since 2.0
030 */
031public class JdkProxySource<T> implements ProxySource<T> {
032
033    private final ClassLoader classLoader;
034    private final Class<?>[] interfaces;
035
036
037    /**
038     * Create a new proxy source for the given interfaces.
039     *
040     * @param classLoader The class loader with which to create the proxy
041     * @param interfaces  The interfaces to proxy
042     */
043    public JdkProxySource(final ClassLoader classLoader, final Class<?>[] interfaces) {
044        this.classLoader = classLoader;
045        // Defensive copy
046        this.interfaces = new Class<?>[interfaces.length];
047        System.arraycopy(interfaces, 0, this.interfaces, 0, interfaces.length);
048    }
049
050
051    @Override
052    public T createProxy(final T pooledObject, final UsageTracking<T> usageTracking) {
053        @SuppressWarnings("unchecked")
054        final
055        T proxy = (T) Proxy.newProxyInstance(classLoader, interfaces,
056                new JdkProxyHandler<>(pooledObject, usageTracking));
057        return proxy;
058    }
059
060
061    @Override
062    public T resolveProxy(final T proxy) {
063        @SuppressWarnings("unchecked")
064        final
065        JdkProxyHandler<T> jdkProxyHandler =
066                (JdkProxyHandler<T>) Proxy.getInvocationHandler(proxy);
067        final T pooledObject = jdkProxyHandler.disableProxy();
068        return pooledObject;
069    }
070
071
072    /**
073     * @since 2.4.3
074     */
075    @Override
076    public String toString() {
077        final StringBuilder builder = new StringBuilder();
078        builder.append("JdkProxySource [classLoader=");
079        builder.append(classLoader);
080        builder.append(", interfaces=");
081        builder.append(Arrays.toString(interfaces));
082        builder.append("]");
083        return builder.toString();
084    }
085}