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 package org.apache.http.client.utils;
28
29 import java.lang.reflect.InvocationTargetException;
30 import java.lang.reflect.Method;
31
32 import org.apache.http.annotation.Immutable;
33
34 /**
35 * A collection of utilities to workaround limitations of Java clone framework.
36 *
37 * @since 4.0
38 */
39 @Immutable
40 public class CloneUtils {
41
42 /**
43 * @since 4.3
44 */
45 @SuppressWarnings("unchecked")
46 public static <T> T cloneObject(final T obj) throws CloneNotSupportedException {
47 if (obj == null) {
48 return null;
49 }
50 if (obj instanceof Cloneable) {
51 final Class<?> clazz = obj.getClass ();
52 Method m;
53 try {
54 m = clazz.getMethod("clone", (Class[]) null);
55 } catch (final NoSuchMethodException ex) {
56 throw new NoSuchMethodError(ex.getMessage());
57 }
58 try {
59 return (T) m.invoke(obj, (Object []) null);
60 } catch (final InvocationTargetException ex) {
61 final Throwable cause = ex.getCause();
62 if (cause instanceof CloneNotSupportedException) {
63 throw ((CloneNotSupportedException) cause);
64 } else {
65 throw new Error("Unexpected exception", cause);
66 }
67 } catch (final IllegalAccessException ex) {
68 throw new IllegalAccessError(ex.getMessage());
69 }
70 } else {
71 throw new CloneNotSupportedException();
72 }
73 }
74
75 public static Object clone(final Object obj) throws CloneNotSupportedException {
76 return cloneObject(obj);
77 }
78
79 /**
80 * This class should not be instantiated.
81 */
82 private CloneUtils() {
83 }
84
85 }