1
14
15 package com.liferay.portal.kernel.util;
16
17 import java.io.IOException;
18 import java.io.ObjectInputStream;
19 import java.io.Serializable;
20
21 import java.util.AbstractSet;
22 import java.util.Collection;
23 import java.util.Iterator;
24 import java.util.Map;
25 import java.util.Set;
26
27
32 public class MapBackedSet<E> extends AbstractSet<E> implements Serializable {
33
34 public MapBackedSet(Map<E, Boolean> backedMap) {
35 if (!backedMap.isEmpty()) {
36 throw new IllegalArgumentException("Map is not empty");
37 }
38
39 _backedMap = backedMap;
40 _backedMapKeySet = backedMap.keySet();
41 }
42
43 public boolean add(E element) {
44 if (_backedMap.put(element, Boolean.TRUE) == null) {
45 return true;
46 }
47 else {
48 return false;
49 }
50 }
51
52 public void clear() {
53 _backedMap.clear();
54 }
55
56 public boolean contains(Object obj) {
57 return _backedMap.containsKey(obj);
58 }
59
60 public boolean containsAll(Collection<?> collection) {
61 return _backedMapKeySet.containsAll(collection);
62 }
63
64 public boolean equals(Object obj) {
65 if ((obj == this) || _backedMapKeySet.equals(obj)) {
66 return true;
67 }
68 else {
69 return false;
70 }
71 }
72
73 public int hashCode() {
74 return _backedMapKeySet.hashCode();
75 }
76
77 public boolean isEmpty() {
78 return _backedMap.isEmpty();
79 }
80
81 public Iterator<E> iterator() {
82 return _backedMapKeySet.iterator();
83 }
84
85 public boolean remove(Object obj) {
86 if (_backedMap.remove(obj) != null) {
87 return true;
88 }
89 else {
90 return false;
91 }
92 }
93
94 public boolean removeAll(Collection<?> collection) {
95 return _backedMapKeySet.removeAll(collection);
96 }
97
98 public boolean retainAll(Collection<?> collection) {
99 return _backedMapKeySet.retainAll(collection);
100 }
101
102 public int size() {
103 return _backedMap.size();
104 }
105
106 public Object[] toArray() {
107 return _backedMapKeySet.toArray();
108 }
109
110 public <T> T[] toArray(T[] array) {
111 return _backedMapKeySet.toArray(array);
112 }
113
114 public String toString() {
115 return _backedMapKeySet.toString();
116 }
117
118 private void readObject(ObjectInputStream objectInputStream)
119 throws ClassNotFoundException, IOException {
120
121 objectInputStream.defaultReadObject();
122
123 _backedMapKeySet = _backedMap.keySet();
124 }
125
126 private final Map<E, Boolean> _backedMap;
127 private transient Set<E> _backedMapKeySet;
128
129 }