View Javadoc
1   /*
2    * Licensed to the Apache Software Foundation (ASF) under one or more
3    * contributor license agreements.  See the NOTICE file distributed with
4    * this work for additional information regarding copyright ownership.
5    * The ASF licenses this file to You under the Apache License, Version 2.0
6    * (the "License"); you may not use this file except in compliance with
7    * the License.  You may obtain a copy of the License at
8    *
9    *      http://www.apache.org/licenses/LICENSE-2.0
10   *
11   * Unless required by applicable law or agreed to in writing, software
12   * distributed under the License is distributed on an "AS IS" BASIS,
13   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14   * See the License for the specific language governing permissions and
15   * limitations under the License.
16   */
17  package org.apache.commons.pool2.proxy;
18  
19  import java.lang.reflect.Proxy;
20  import java.util.Arrays;
21  
22  import org.apache.commons.pool2.UsageTracking;
23  
24  /**
25   * Provides proxy objects using Java reflection.
26   *
27   * @param <T> type of the pooled object to be proxied
28   * @since 2.0
29   */
30  public class JdkProxySource<T> implements ProxySource<T> {
31  
32      private final ClassLoader classLoader;
33      private final Class<?>[] interfaces;
34  
35      /**
36       * Constructs a new proxy source for the given interfaces.
37       *
38       * @param classLoader The class loader with which to create the proxy
39       * @param interfaces  The interfaces to proxy
40       */
41      public JdkProxySource(final ClassLoader classLoader, final Class<?>[] interfaces) {
42          this.classLoader = classLoader;
43          // Defensive copy
44          this.interfaces = Arrays.copyOf(interfaces, interfaces.length);
45      }
46  
47      @SuppressWarnings("unchecked") // Cast to T on return.
48      @Override
49      public T createProxy(final T pooledObject, final UsageTracking<T> usageTracking) {
50          return (T) Proxy.newProxyInstance(classLoader, interfaces,
51                  new JdkProxyHandler<>(pooledObject, usageTracking));
52      }
53  
54      @SuppressWarnings("unchecked")
55      @Override
56      public T resolveProxy(final T proxy) {
57          return ((JdkProxyHandler<T>) Proxy.getInvocationHandler(proxy)).disableProxy();
58      }
59  
60      /**
61       * @since 2.4.3
62       */
63      @Override
64      public String toString() {
65          final StringBuilder builder = new StringBuilder();
66          builder.append("JdkProxySource [classLoader=");
67          builder.append(classLoader);
68          builder.append(", interfaces=");
69          builder.append(Arrays.toString(interfaces));
70          builder.append("]");
71          return builder.toString();
72      }
73  }