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1
28
29 package org.jruby.util;
30
31 import java.util.AbstractCollection  ;
32 import java.util.AbstractSet ;
33 import java.util.Collection ;
34 import java.util.Iterator ;
35 import java.util.Map ;
36 import java.util.Set ;
37
38
45
46 abstract class GenericMap implements Map {
47 protected int size;
48
49 public int size() {
50 return size;
51 }
52
53 public boolean isEmpty() {
54 return size() == 0;
55 }
56
57 protected int keyHash(Object key) {
58 if (key == null)
59 return 0;
60 else
61 return key.hashCode();
62 }
63
64 protected boolean keyEquals(Object containedKey, Object givenKey) {
65 if (containedKey == null)
66 return givenKey == null;
67 else
68 return containedKey.equals(givenKey);
69 }
70
71 protected int valueHash(Object value) {
72 if (value == null)
73 return 0;
74 else
75 return value.hashCode();
76 }
77
78 protected boolean valueEquals(Object value1, Object value2) {
79 if (value1 == null)
80 return value2 == null;
81 else
82 return value1.equals(value2);
83 }
84
85 abstract class Entry implements Map.Entry {
86 public int hashCode() {
87 return keyHash(getKey()) ^ valueHash(getValue());
88 }
89
90 public boolean equals(Object other) {
91 if (other instanceof Map.Entry ) {
92 Map.Entry ent = (Map.Entry ) other;
93 return keyEquals(getKey(), ent.getKey())
94 && valueEquals(getValue(), ent.getValue());
95 } else {
96 return false;
97 }
98 }
99
100 }
101
102 public void putAll(Map other) {
103 if (other == this)
104 return;
105
106 Iterator it = other.entrySet().iterator();
107 while (it.hasNext()) {
108 Map.Entry entry = (Map.Entry ) it.next();
109 put(entry.getKey(), entry.getValue());
110 }
111 }
112
113 protected abstract Iterator entryIterator();
114
115 protected Iterator keyIterator() {
116 return new KeyIterator();
117 }
118
119 protected Iterator valueIterator() {
120 return new ValueIterator();
121 }
122
123 abstract class KeyOrValueIterator implements Iterator {
124 Iterator iter = entryIterator();
125
126 public boolean hasNext() {
127 return iter.hasNext();
128 }
129
130 protected Map.Entry nextEntry() {
131 return (Map.Entry ) iter.next();
132 }
133
134 public void remove() {
135 throw new UnsupportedOperationException ();
136 }
137
138 }
139
140 class KeyIterator extends KeyOrValueIterator {
141 public Object next() {
142 return nextEntry().getKey();
143 }
144 }
145
146 class ValueIterator extends KeyOrValueIterator {
147 public Object next() {
148 return nextEntry().getValue();
149 }
150 }
151
152
157
158 private static Object [] toArray(Object [] arr, int size, Iterator it) {
159 Object [] out;
160
161 if (arr != null && arr.length >= size) {
162 out = arr;
163 } else if (arr == null) {
164 out = new Object [size];
165 } else {
166 out = (Object []) java.lang.reflect.Array.newInstance(arr.getClass()
167 .getComponentType(), size);
168 }
169
170 for (int i = 0; i < size; i++) {
171 out[i] = it.next();
172 }
173
174 if (out.length > size)
175 out[size] = null;
176
177 return out;
178 }
179
180 public Collection values() {
181 return new AbstractCollection () {
182 public Iterator iterator() {
183 return valueIterator();
184 }
185
186 public int size() {
187 return GenericMap.this.size();
188 }
189
190 public Object [] toArray(Object [] arr) {
191 return GenericMap.toArray(arr, size(), iterator());
192 }
193 };
194 }
195
196 public Set keySet() {
197 return new AbstractSet () {
198 public Iterator iterator() {
199 return keyIterator();
200 }
201
202 public int size() {
203 return GenericMap.this.size();
204 }
205
206 public Object [] toArray(Object [] arr) {
207 return GenericMap.toArray(arr, size(), iterator());
208 }
209 };
210 }
211
212 public int hashCode() {
213 int code = 0;
214 Iterator it = entryIterator();
215 while (it.hasNext()) {
216 code += it.next().hashCode();
217 }
218 return code;
219 }
220
221 public boolean equals(Object other) {
222 if (other instanceof Map ) {
223 Map map = (Map ) other;
224
225 if (map.size() != size())
226 return false;
227
228 Iterator it = entryIterator();
229 while (it.hasNext()) {
230 Entry ent = (Entry) it.next();
231 Object key = ent.getKey();
232 Object val = ent.getValue();
233
234 if (map.containsKey(key)) {
235 Object otherVal = map.get(key);
236 if (!valueEquals(val, otherVal))
237 return false;
238 }
239 }
240 return true;
241 }
242 return false;
243 }
244
245 public Set entrySet() {
246 return new AbstractSet () {
247 public Iterator iterator() {
248 return entryIterator();
249 }
250
251 public int size() {
252 return size;
253 }
254
255 public Object [] toArray(Object [] arr) {
256 return GenericMap.toArray(arr, size(), iterator());
257 }
258 };
259 }
260
261
262 public boolean containsValue(Object value) {
263 Iterator it = valueIterator();
264 while (it.hasNext()) {
265 if (valueEquals(value, it.next()))
266 return true;
267 }
268 return false;
269 }
270
271 public boolean containsKey(Object key) {
272 return get(key) != null;
273 }
274 }
275 |
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