01: /*
02: * Copyright 2001-2004 The Apache Software Foundation
03: *
04: * Licensed under the Apache License, Version 2.0 (the "License");
05: * you may not use this file except in compliance with the License.
06: * You may obtain a copy of the License at
07: *
08: * http://www.apache.org/licenses/LICENSE-2.0
09: *
10: * Unless required by applicable law or agreed to in writing, software
11: * distributed under the License is distributed on an "AS IS" BASIS,
12: * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13: * See the License for the specific language governing permissions and
14: * limitations under the License.
15: */
16: package org.apache.commons.collections.functors;
17:
18: import java.io.Serializable;
19:
20: import org.apache.commons.collections.Transformer;
21:
22: /**
23: * Transformer implementation that returns a clone of the input object.
24: * <p>
25: * Clone is performed using <code>PrototypeFactory.getInstance(input).create()</code>.
26: *
27: * @since Commons Collections 3.0
28: * @version $Revision: 348444 $ $Date: 2005-11-23 14:06:56 +0000 (Wed, 23 Nov 2005) $
29: *
30: * @author Stephen Colebourne
31: */
32: public class CloneTransformer implements Transformer, Serializable {
33:
34: /** Serial version UID */
35: private static final long serialVersionUID = -8188742709499652567L;
36:
37: /** Singleton predicate instance */
38: public static final Transformer INSTANCE = new CloneTransformer();
39:
40: /**
41: * Factory returning the singleton instance.
42: *
43: * @return the singleton instance
44: * @since Commons Collections 3.1
45: */
46: public static Transformer getInstance() {
47: return INSTANCE;
48: }
49:
50: /**
51: * Constructor
52: */
53: private CloneTransformer() {
54: super ();
55: }
56:
57: /**
58: * Transforms the input to result by cloning it.
59: *
60: * @param input the input object to transform
61: * @return the transformed result
62: */
63: public Object transform(Object input) {
64: if (input == null) {
65: return null;
66: }
67: return PrototypeFactory.getInstance(input).create();
68: }
69:
70: }
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