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.collections4.keyvalue;
18
19 import java.util.Map;
20 import java.util.Objects;
21
22 import org.apache.commons.collections4.KeyValue;
23
24 /**
25 * Provides a base decorator that allows additional functionality to be
26 * added to a {@link java.util.Map.Entry Map.Entry}.
27 *
28 * @param <K> the type of keys
29 * @param <V> the type of mapped values
30 * @since 3.0
31 */
32 public abstract class AbstractMapEntryDecorator<K, V> implements Map.Entry<K, V>, KeyValue<K, V> {
33
34 /** The {@code Map.Entry} to decorate */
35 private final Map.Entry<K, V> entry;
36
37 /**
38 * Constructor that wraps (not copies).
39 *
40 * @param entry the {@code Map.Entry} to decorate, must not be null
41 * @throws NullPointerException if the collection is null
42 */
43 public AbstractMapEntryDecorator(final Map.Entry<K, V> entry) {
44 this.entry = Objects.requireNonNull(entry, "entry");
45 }
46
47 @Override
48 public boolean equals(final Object object) {
49 if (object == this) {
50 return true;
51 }
52 return entry.equals(object);
53 }
54
55 @Override
56 public K getKey() {
57 return entry.getKey();
58 }
59
60 /**
61 * Gets the map being decorated.
62 *
63 * @return the decorated map
64 */
65 protected Map.Entry<K, V> getMapEntry() {
66 return entry;
67 }
68
69 @Override
70 public V getValue() {
71 return entry.getValue();
72 }
73
74 @Override
75 public int hashCode() {
76 return entry.hashCode();
77 }
78
79 @Override
80 public V setValue(final V object) {
81 return entry.setValue(object);
82 }
83
84 @Override
85 public String toString() {
86 return entry.toString();
87 }
88
89 }