1 /*
2 * ====================================================================
3 * Licensed to the Apache Software Foundation (ASF) under one
4 * or more contributor license agreements. See the NOTICE file
5 * distributed with this work for additional information
6 * regarding copyright ownership. The ASF licenses this file
7 * to you under the Apache License, Version 2.0 (the
8 * "License"); you may not use this file except in compliance
9 * with the License. You may obtain a copy of the License at
10 *
11 * http://www.apache.org/licenses/LICENSE-2.0
12 *
13 * Unless required by applicable law or agreed to in writing,
14 * software distributed under the License is distributed on an
15 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
16 * KIND, either express or implied. See the License for the
17 * specific language governing permissions and limitations
18 * under the License.
19 * ====================================================================
20 *
21 * This software consists of voluntary contributions made by many
22 * individuals on behalf of the Apache Software Foundation. For more
23 * information on the Apache Software Foundation, please see
24 * <http://www.apache.org/>.
25 *
26 */
27
28 package org.apache.http.impl.client.cache;
29
30 import java.io.Closeable;
31 import java.io.IOException;
32 import java.lang.reflect.InvocationHandler;
33 import java.lang.reflect.InvocationTargetException;
34 import java.lang.reflect.Method;
35
36 import org.apache.http.HttpResponse;
37
38 /**
39 * A proxy class that can enhance an arbitrary {@link HttpResponse} with
40 * {@link Closeable#close()} method.
41 *
42 * @since 4.3
43 */
44 class ResponseProxyHandler implements InvocationHandler {
45
46 private static final Method CLOSE_METHOD;
47
48 static {
49 try {
50 CLOSE_METHOD = Closeable.class.getMethod("close");
51 } catch (final NoSuchMethodException ex) {
52 throw new Error(ex);
53 }
54 }
55
56 private final HttpResponse original;
57
58 ResponseProxyHandler(final HttpResponse original) {
59 super();
60 this.original = original;
61 }
62
63 public void close() throws IOException {
64 IOUtils.consume(original.getEntity());
65 }
66
67 @Override
68 public Object invoke(
69 final Object proxy, final Method method, final Object[] args) throws Throwable {
70 if (method.equals(CLOSE_METHOD)) {
71 close();
72 return null;
73 } else {
74 try {
75 return method.invoke(this.original, args);
76 } catch (final InvocationTargetException ex) {
77 final Throwable cause = ex.getCause();
78 if (cause != null) {
79 throw cause;
80 } else {
81 throw ex;
82 }
83 }
84 }
85 }
86
87 }