| 33 |
|
* implementation in detail. Each of these methods may be overridden if the |
| 34 |
|
* map being implemented admits a more efficient implementation.<p> |
| 35 |
|
* |
| 36 |
< |
* This class is a member of the |
| 36 |
> |
* This class is a member of the |
| 37 |
|
* <a href="{@docRoot}/../guide/collections/index.html"> |
| 38 |
|
* Java Collections Framework</a>. |
| 39 |
|
* |
| 40 |
+ |
* @param <K> the type of keys maintained by this map |
| 41 |
+ |
* @param <V> the type of mapped values |
| 42 |
+ |
* |
| 43 |
|
* @author Josh Bloch |
| 44 |
|
* @author Neal Gafter |
| 45 |
|
* @version %I%, %G% |
| 87 |
|
* More formally, returns <tt>true</tt> if and only if this map contains |
| 88 |
|
* at least one mapping to a value <tt>v</tt> such that <tt>(value==null ? |
| 89 |
|
* v==null : value.equals(v))</tt>. This operation will probably require |
| 90 |
< |
* time linear in the map size for most implementations of map.<p> |
| 90 |
> |
* time linear in the map size for most implementations of <tt>Map</tt>.<p> |
| 91 |
|
* |
| 92 |
< |
* This implementation iterates over entrySet() searching for an entry |
| 92 |
> |
* This implementation iterates over <tt>entrySet()</tt> searching for an entry |
| 93 |
|
* with the specified value. If such an entry is found, <tt>true</tt> is |
| 94 |
|
* returned. If the iteration terminates without finding such an entry, |
| 95 |
|
* <tt>false</tt> is returned. Note that this implementation requires |
| 96 |
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* linear time in the size of the map. |
| 97 |
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* |
| 98 |
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* @param value value whose presence in this map is to be tested. |
| 99 |
< |
* |
| 99 |
> |
* |
| 100 |
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* @return <tt>true</tt> if this map maps one or more keys to this value. |
| 101 |
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*/ |
| 102 |
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public boolean containsValue(Object value) { |
| 130 |
|
* |
| 131 |
|
* @param key key whose presence in this map is to be tested. |
| 132 |
|
* @return <tt>true</tt> if this map contains a mapping for the specified |
| 133 |
< |
* key. |
| 134 |
< |
* |
| 135 |
< |
* @throws NullPointerException if the key is <tt>null</tt> and this map |
| 133 |
< |
* does not permit <tt>null</tt> keys. |
| 133 |
> |
* key. |
| 134 |
> |
* @throws NullPointerException if <tt>key</tt> is <tt>null</tt> |
| 135 |
> |
* and this map does not permit <tt>null</tt> keys. |
| 136 |
|
*/ |
| 137 |
|
public boolean containsKey(Object key) { |
| 138 |
|
Iterator<Map.Entry<K,V>> i = entrySet().iterator(); |
| 169 |
|
* |
| 170 |
|
* @param key key whose associated value is to be returned. |
| 171 |
|
* @return the value to which this map maps the specified key. |
| 172 |
< |
* |
| 173 |
< |
* @throws NullPointerException if the key is <tt>null</tt> and this map |
| 174 |
< |
* does not permit <tt>null</tt> keys. |
| 175 |
< |
* |
| 172 |
> |
* |
| 173 |
> |
* @throws NullPointerException if <tt>key</tt> is <tt>null</tt> |
| 174 |
> |
* and this map does not permit <tt>null</tt> keys. |
| 175 |
> |
* |
| 176 |
|
* @see #containsKey(Object) |
| 177 |
|
*/ |
| 178 |
|
public V get(Object key) { |
| 206 |
|
* |
| 207 |
|
* @param key key with which the specified value is to be associated. |
| 208 |
|
* @param value value to be associated with the specified key. |
| 209 |
< |
* |
| 209 |
> |
* |
| 210 |
|
* @return the previous value associated with specified key, or <tt>null</tt> |
| 211 |
|
* if there was no mapping for key. (A <tt>null</tt> return can |
| 212 |
|
* also indicate that the map previously associated <tt>null</tt> |
| 213 |
|
* with the specified key, if the implementation supports |
| 214 |
|
* <tt>null</tt> values.) |
| 215 |
< |
* |
| 216 |
< |
* @throws UnsupportedOperationException if the <tt>put</tt> operation is |
| 217 |
< |
* not supported by this map. |
| 216 |
< |
* |
| 215 |
> |
* |
| 216 |
> |
* @throws UnsupportedOperationException if the <tt>put</tt> operation |
| 217 |
> |
* is not supported by this map. |
| 218 |
|
* @throws ClassCastException if the class of the specified key or value |
| 219 |
< |
* prevents it from being stored in this map. |
| 220 |
< |
* |
| 221 |
< |
* @throws IllegalArgumentException if some aspect of this key or value * |
| 221 |
< |
* prevents it from being stored in this map. |
| 222 |
< |
* |
| 219 |
> |
* prevents it from being stored in this map. |
| 220 |
> |
* @throws IllegalArgumentException if some aspect of this key or value |
| 221 |
> |
* prevents it from being stored in this map. |
| 222 |
|
* @throws NullPointerException if this map does not permit <tt>null</tt> |
| 223 |
< |
* keys or values, and the specified key or value is |
| 225 |
< |
* <tt>null</tt>. |
| 223 |
> |
* keys or values, and the specified key or value is <tt>null</tt>. |
| 224 |
|
*/ |
| 225 |
|
public V put(K key, V value) { |
| 226 |
|
throw new UnsupportedOperationException(); |
| 233 |
|
* This implementation iterates over <tt>entrySet()</tt> searching for an |
| 234 |
|
* entry with the specified key. If such an entry is found, its value is |
| 235 |
|
* obtained with its <tt>getValue</tt> operation, the entry is removed |
| 236 |
< |
* from the Collection (and the backing map) with the iterator's |
| 236 |
> |
* from the collection (and the backing map) with the iterator's |
| 237 |
|
* <tt>remove</tt> operation, and the saved value is returned. If the |
| 238 |
|
* iteration terminates without finding such an entry, <tt>null</tt> is |
| 239 |
|
* returned. Note that this implementation requires linear time in the |
| 251 |
|
* with the specified key, if the implementation supports |
| 252 |
|
* <tt>null</tt> values.) |
| 253 |
|
* @throws UnsupportedOperationException if the <tt>remove</tt> operation |
| 254 |
< |
* is not supported by this map. |
| 254 |
> |
* is not supported by this map. |
| 255 |
|
*/ |
| 256 |
|
public V remove(Object key) { |
| 257 |
|
Iterator<Entry<K,V>> i = entrySet().iterator(); |
| 295 |
|
* the <tt>put</tt> operation and the specified map is nonempty. |
| 296 |
|
* |
| 297 |
|
* @param t mappings to be stored in this map. |
| 298 |
< |
* |
| 298 |
> |
* |
| 299 |
|
* @throws UnsupportedOperationException if the <tt>putAll</tt> operation |
| 300 |
< |
* is not supported by this map. |
| 303 |
< |
* |
| 300 |
> |
* is not supported by this map. |
| 301 |
|
* @throws ClassCastException if the class of a key or value in the |
| 302 |
< |
* specified map prevents it from being stored in this map. |
| 306 |
< |
* |
| 302 |
> |
* specified map prevents it from being stored in this map. |
| 303 |
|
* @throws IllegalArgumentException if some aspect of a key or value in |
| 304 |
< |
* the specified map prevents it from being stored in this map. |
| 304 |
> |
* the specified map prevents it from being stored in this map. |
| 305 |
|
* @throws NullPointerException if the specified map is <tt>null</tt>, or if |
| 306 |
|
* this map does not permit <tt>null</tt> keys or values, and the |
| 307 |
|
* specified map contains <tt>null</tt> keys or values. |
| 323 |
|
* <tt>UnsupportedOperationException</tt> if the <tt>entrySet</tt> |
| 324 |
|
* does not support the <tt>clear</tt> operation. |
| 325 |
|
* |
| 326 |
< |
* @throws UnsupportedOperationException clear is not supported |
| 327 |
< |
* by this map. |
| 326 |
> |
* @throws UnsupportedOperationException if the <tt>clear</tt> operation |
| 327 |
> |
* is not supported by this map. |
| 328 |
|
*/ |
| 329 |
|
public void clear() { |
| 330 |
|
entrySet().clear(); |
| 342 |
|
transient volatile Collection<V> values = null; |
| 343 |
|
|
| 344 |
|
/** |
| 345 |
< |
* Returns a Set view of the keys contained in this map. The Set is |
| 346 |
< |
* backed by the map, so changes to the map are reflected in the Set, |
| 347 |
< |
* and vice-versa. (If the map is modified while an iteration over |
| 348 |
< |
* the Set is in progress, the results of the iteration are undefined.) |
| 349 |
< |
* The Set supports element removal, which removes the corresponding entry |
| 350 |
< |
* from the map, via the Iterator.remove, Set.remove, removeAll |
| 351 |
< |
* retainAll, and clear operations. It does not support the add or |
| 352 |
< |
* addAll operations.<p> |
| 353 |
< |
* |
| 354 |
< |
* This implementation returns a Set that subclasses |
| 355 |
< |
* AbstractSet. The subclass's iterator method returns a "wrapper |
| 356 |
< |
* object" over this map's entrySet() iterator. The size method delegates |
| 357 |
< |
* to this map's size method and the contains method delegates to this |
| 358 |
< |
* map's containsKey method.<p> |
| 345 |
> |
* Returns a {@link Set} view of the keys contained in this map. |
| 346 |
> |
* The set is backed by the map, so changes to the map are |
| 347 |
> |
* reflected in the set, and vice-versa. If the map is modified |
| 348 |
> |
* while an iteration over the set is in progress (except through |
| 349 |
> |
* the iterator's own <tt>remove</tt> operation), the results of |
| 350 |
> |
* the iteration are undefined. The set supports element removal, |
| 351 |
> |
* which removes the corresponding mapping from the map, via the |
| 352 |
> |
* <tt>Iterator.remove</tt>, <tt>Set.remove</tt>, |
| 353 |
> |
* <tt>removeAll</tt> <tt>retainAll</tt>, and <tt>clear</tt> |
| 354 |
> |
* operations. It does not support the add or <tt>addAll</tt> |
| 355 |
> |
* operations. |
| 356 |
> |
* |
| 357 |
> |
* <p>This implementation returns a set that subclasses {@link AbstractSet}. |
| 358 |
> |
* The subclass's iterator method returns a "wrapper object" over this |
| 359 |
> |
* map's <tt>entrySet()</tt> iterator. The <tt>size</tt> method |
| 360 |
> |
* delegates to this map's <tt>size</tt> method and the |
| 361 |
> |
* <tt>contains</tt> method delegates to this map's |
| 362 |
> |
* <tt>containsKey</tt> method. |
| 363 |
|
* |
| 364 |
< |
* The Set is created the first time this method is called, |
| 364 |
> |
* <p>The set is created the first time this method is called, |
| 365 |
|
* and returned in response to all subsequent calls. No synchronization |
| 366 |
|
* is performed, so there is a slight chance that multiple calls to this |
| 367 |
< |
* method will not all return the same Set. |
| 368 |
< |
* |
| 369 |
< |
* @return a Set view of the keys contained in this map. |
| 367 |
> |
* method will not all return the same set. |
| 368 |
|
*/ |
| 369 |
|
public Set<K> keySet() { |
| 370 |
|
if (keySet == null) { |
| 400 |
|
} |
| 401 |
|
|
| 402 |
|
/** |
| 403 |
< |
* Returns a collection view of the values contained in this map. The |
| 404 |
< |
* collection is backed by the map, so changes to the map are reflected in |
| 405 |
< |
* the collection, and vice-versa. (If the map is modified while an |
| 406 |
< |
* iteration over the collection is in progress, the results of the |
| 407 |
< |
* iteration are undefined.) The collection supports element removal, |
| 408 |
< |
* which removes the corresponding entry from the map, via the |
| 409 |
< |
* <tt>Iterator.remove</tt>, <tt>Collection.remove</tt>, |
| 410 |
< |
* <tt>removeAll</tt>, <tt>retainAll</tt> and <tt>clear</tt> operations. |
| 411 |
< |
* It does not support the <tt>add</tt> or <tt>addAll</tt> operations.<p> |
| 412 |
< |
* |
| 413 |
< |
* This implementation returns a collection that subclasses abstract |
| 414 |
< |
* collection. The subclass's iterator method returns a "wrapper object" |
| 415 |
< |
* over this map's <tt>entrySet()</tt> iterator. The size method |
| 416 |
< |
* delegates to this map's size method and the contains method delegates |
| 417 |
< |
* to this map's containsValue method.<p> |
| 403 |
> |
* Returns a {@link Collection} view of the values contained in this map. |
| 404 |
> |
* The collection is backed by the map, so changes to the map are |
| 405 |
> |
* reflected in the collection, and vice-versa. If the map is |
| 406 |
> |
* modified while an iteration over the collection is in progress |
| 407 |
> |
* (except through the iterator's own <tt>remove</tt> operation), |
| 408 |
> |
* the results of the iteration are undefined. The collection |
| 409 |
> |
* supports element removal, which removes the corresponding |
| 410 |
> |
* mapping from the map, via the <tt>Iterator.remove</tt>, |
| 411 |
> |
* <tt>Collection.remove</tt>, <tt>removeAll</tt>, |
| 412 |
> |
* <tt>retainAll</tt> and <tt>clear</tt> operations. It does not |
| 413 |
> |
* support the add or <tt>addAll</tt> operations. |
| 414 |
> |
* |
| 415 |
> |
* <p>This implementation returns a collection that subclasses {@link |
| 416 |
> |
* AbstractCollection}. The subclass's iterator method returns a |
| 417 |
> |
* "wrapper object" over this map's <tt>entrySet()</tt> iterator. |
| 418 |
> |
* The <tt>size</tt> method delegates to this map's <tt>size</tt> |
| 419 |
> |
* method and the <tt>contains</tt> method delegates to this map's |
| 420 |
> |
* <tt>containsValue</tt> method. |
| 421 |
|
* |
| 422 |
< |
* The collection is created the first time this method is called, and |
| 422 |
> |
* <p>The collection is created the first time this method is called, and |
| 423 |
|
* returned in response to all subsequent calls. No synchronization is |
| 424 |
|
* performed, so there is a slight chance that multiple calls to this |
| 425 |
< |
* method will not all return the same Collection. |
| 425 |
> |
* method will not all return the same collection. |
| 426 |
|
* |
| 427 |
|
* @return a collection view of the values contained in this map. |
| 428 |
|
*/ |
| 459 |
|
return values; |
| 460 |
|
} |
| 461 |
|
|
| 461 |
– |
/** |
| 462 |
– |
* Returns a set view of the mappings contained in this map. Each element |
| 463 |
– |
* in this set is a Map.Entry. The set is backed by the map, so changes |
| 464 |
– |
* to the map are reflected in the set, and vice-versa. (If the map is |
| 465 |
– |
* modified while an iteration over the set is in progress, the results of |
| 466 |
– |
* the iteration are undefined.) The set supports element removal, which |
| 467 |
– |
* removes the corresponding entry from the map, via the |
| 468 |
– |
* <tt>Iterator.remove</tt>, <tt>Set.remove</tt>, <tt>removeAll</tt>, |
| 469 |
– |
* <tt>retainAll</tt> and <tt>clear</tt> operations. It does not support |
| 470 |
– |
* the <tt>add</tt> or <tt>addAll</tt> operations. |
| 471 |
– |
* |
| 472 |
– |
* @return a set view of the mappings contained in this map. |
| 473 |
– |
*/ |
| 462 |
|
public abstract Set<Entry<K,V>> entrySet(); |
| 463 |
|
|
| 464 |
|
|
| 511 |
|
return false; |
| 512 |
|
} |
| 513 |
|
} |
| 514 |
< |
} catch(ClassCastException unused) { |
| 514 |
> |
} catch (ClassCastException unused) { |
| 515 |
|
return false; |
| 516 |
< |
} catch(NullPointerException unused) { |
| 516 |
> |
} catch (NullPointerException unused) { |
| 517 |
|
return false; |
| 518 |
|
} |
| 519 |
|
|
| 592 |
|
buf.append("}"); |
| 593 |
|
return buf.toString(); |
| 594 |
|
} |
| 595 |
< |
|
| 595 |
> |
|
| 596 |
|
/** |
| 597 |
|
* Returns a shallow copy of this <tt>AbstractMap</tt> instance: the keys |
| 598 |
|
* and values themselves are not cloned. |
