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 * https://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.collections4.set;
18
19 import java.util.Set;
20
21 import org.apache.commons.collections4.collection.AbstractCollectionDecorator;
22
23 /**
24 * Decorates another {@code Set} to provide additional behavior.
25 * <p>
26 * Methods are forwarded directly to the decorated set.
27 * </p>
28 *
29 * @param <E> The type of the elements in this set
30 * @since 3.0
31 */
32 public abstract class AbstractSetDecorator<E> extends AbstractCollectionDecorator<E> implements
33 Set<E> {
34
35 /** Serialization version */
36 private static final long serialVersionUID = -4678668309576958546L;
37
38 /**
39 * Constructor only used in deserialization, do not use otherwise.
40 *
41 * @since 3.1
42 */
43 protected AbstractSetDecorator() {
44 }
45
46 /**
47 * Constructor that wraps (not copies).
48 *
49 * @param set The set to decorate, must not be null
50 * @throws NullPointerException if set is null
51 */
52 protected AbstractSetDecorator(final Set<E> set) {
53 super(set);
54 }
55
56 /**
57 * Gets the set being decorated.
58 *
59 * @return The decorated set
60 */
61 @Override
62 protected Set<E> decorated() {
63 return (Set<E>) super.decorated();
64 }
65
66 @Override
67 public boolean equals(final Object object) {
68 return object == this || decorated().equals(object);
69 }
70
71 @Override
72 public int hashCode() {
73 return decorated().hashCode();
74 }
75
76 }