| 18 |
|
* used. |
| 19 |
|
* |
| 20 |
|
* <p>This implementation provides expected average <i>log(n)</i> time |
| 21 |
< |
* cost for the <tt>contains</tt>, <tt>add</tt>, and <tt>remove</tt> |
| 21 |
> |
* cost for the {@code contains}, {@code add}, and {@code remove} |
| 22 |
|
* operations and their variants. Insertion, removal, and access |
| 23 |
|
* operations safely execute concurrently by multiple |
| 24 |
|
* threads. Iterators are <i>weakly consistent</i>, returning elements |
| 27 |
|
* ConcurrentModificationException}, and may proceed concurrently with |
| 28 |
|
* other operations. |
| 29 |
|
* |
| 30 |
< |
* <p>Beware that, unlike in most collections, the <tt>size</tt> |
| 30 |
> |
* <p>Beware that, unlike in most collections, the {@code size} |
| 31 |
|
* method is <em>not</em> a constant-time operation. Because of the |
| 32 |
|
* asynchronous nature of these sets, determining the current number |
| 33 |
|
* of elements requires a traversal of the elements. Additionally, the |
| 34 |
< |
* bulk operations <tt>addAll</tt>, <tt>removeAll</tt>, |
| 35 |
< |
* <<tt>retainAll</tt>, and tt>containsAll</tt> are <em>not</em> |
| 34 |
> |
* bulk operations {@code addAll}, {@code removeAll}, |
| 35 |
> |
* <{@code retainAll}, and tt>containsAll</tt> are <em>not</em> |
| 36 |
|
* guaranteed to be performed atomically. For example, an iterator |
| 37 |
< |
* operating concurrently with an <tt>addAll</tt> operation might view |
| 37 |
> |
* operating concurrently with an {@code addAll} operation might view |
| 38 |
|
* only some of the added elements. |
| 39 |
|
* |
| 40 |
|
* <p>This class and its iterators implement all of the |
| 41 |
|
* <em>optional</em> methods of the {@link Set} and {@link Iterator} |
| 42 |
|
* interfaces. Like most other concurrent collection implementations, |
| 43 |
< |
* this class does not permit the use of <tt>null</tt> elements. |
| 44 |
< |
* because <tt>null</tt> arguments and return values cannot be reliably |
| 43 |
> |
* this class does not permit the use of {@code null} elements. |
| 44 |
> |
* because {@code null} arguments and return values cannot be reliably |
| 45 |
|
* distinguished from the absence of elements. |
| 46 |
|
* |
| 47 |
|
* @author Doug Lea |
| 75 |
|
* comparator. |
| 76 |
|
* |
| 77 |
|
* @param c the comparator that will be used to sort this set. A |
| 78 |
< |
* <tt>null</tt> value indicates that the elements' <i>natural |
| 78 |
> |
* {@code null} value indicates that the elements' <i>natural |
| 79 |
|
* ordering</i> should be used. |
| 80 |
|
*/ |
| 81 |
|
public ConcurrentSkipListSet(Comparator<? super E> c) { |
| 91 |
|
* @throws ClassCastException if the elements in the specified |
| 92 |
|
* collection are not comparable, or are not mutually comparable |
| 93 |
|
* @throws NullPointerException if the specified collection is |
| 94 |
< |
* <tt>null</tt> |
| 94 |
> |
* {@code null} |
| 95 |
|
*/ |
| 96 |
|
public ConcurrentSkipListSet(Collection<? extends E> c) { |
| 97 |
|
m = new ConcurrentSkipListMap<E,Object>(); |
| 104 |
|
* |
| 105 |
|
* @param s sorted set whose elements will comprise the new set |
| 106 |
|
* @throws NullPointerException if the specified sorted set is |
| 107 |
< |
* <tt>null</tt> |
| 107 |
> |
* {@code null} |
| 108 |
|
*/ |
| 109 |
|
public ConcurrentSkipListSet(SortedSet<E> s) { |
| 110 |
|
m = new ConcurrentSkipListMap<E,Object>(s.comparator()); |
| 134 |
|
|
| 135 |
|
/** |
| 136 |
|
* Returns the number of elements in this set. If this set |
| 137 |
< |
* contains more than <tt>Integer.MAX_VALUE</tt> elements, it |
| 138 |
< |
* returns <tt>Integer.MAX_VALUE</tt>. |
| 137 |
> |
* contains more than {@code Integer.MAX_VALUE} elements, it |
| 138 |
> |
* returns {@code Integer.MAX_VALUE}. |
| 139 |
|
* |
| 140 |
|
* <p>Beware that, unlike in most collections, this method is |
| 141 |
|
* <em>NOT</em> a constant-time operation. Because of the |
| 153 |
|
} |
| 154 |
|
|
| 155 |
|
/** |
| 156 |
< |
* Returns <tt>true</tt> if this set contains no elements. |
| 157 |
< |
* @return <tt>true</tt> if this set contains no elements |
| 156 |
> |
* Returns {@code true} if this set contains no elements. |
| 157 |
> |
* @return {@code true} if this set contains no elements |
| 158 |
|
*/ |
| 159 |
|
public boolean isEmpty() { |
| 160 |
|
return m.isEmpty(); |
| 161 |
|
} |
| 162 |
|
|
| 163 |
|
/** |
| 164 |
< |
* Returns <tt>true</tt> if this set contains the specified element. |
| 164 |
> |
* Returns {@code true} if this set contains the specified element. |
| 165 |
|
* |
| 166 |
|
* @param o the object to be checked for containment in this set |
| 167 |
< |
* @return <tt>true</tt> if this set contains the specified element |
| 167 |
> |
* @return {@code true} if this set contains the specified element |
| 168 |
|
* |
| 169 |
|
* @throws ClassCastException if the specified object cannot be compared |
| 170 |
|
* with the elements currently in the set |
| 171 |
< |
* @throws NullPointerException if o is <tt>null</tt> |
| 171 |
> |
* @throws NullPointerException if o is {@code null} |
| 172 |
|
*/ |
| 173 |
|
public boolean contains(Object o) { |
| 174 |
|
return m.containsKey(o); |
| 178 |
|
* Adds the specified element to this set if it is not already present. |
| 179 |
|
* |
| 180 |
|
* @param o element to be added to this set |
| 181 |
< |
* @return <tt>true</tt> if the set did not already contain the specified |
| 181 |
> |
* @return {@code true} if the set did not already contain the specified |
| 182 |
|
* element |
| 183 |
|
* |
| 184 |
|
* @throws ClassCastException if the specified object cannot be compared |
| 185 |
|
* with the elements currently in the set |
| 186 |
< |
* @throws NullPointerException if o is <tt>null</tt> |
| 186 |
> |
* @throws NullPointerException if o is {@code null} |
| 187 |
|
*/ |
| 188 |
|
public boolean add(E o) { |
| 189 |
|
return m.putIfAbsent(o, Boolean.TRUE) == null; |
| 193 |
|
* Removes the specified element from this set if it is present. |
| 194 |
|
* |
| 195 |
|
* @param o object to be removed from this set, if present |
| 196 |
< |
* @return <tt>true</tt> if the set contained the specified element |
| 196 |
> |
* @return {@code true} if the set contained the specified element |
| 197 |
|
* |
| 198 |
|
* @throws ClassCastException if the specified object cannot be compared |
| 199 |
|
* with the elements currently in the set |
| 200 |
< |
* @throws NullPointerException if o is <tt>null</tt> |
| 200 |
> |
* @throws NullPointerException if o is {@code null} |
| 201 |
|
*/ |
| 202 |
|
public boolean remove(Object o) { |
| 203 |
|
return m.removep(o); |
| 234 |
|
|
| 235 |
|
/** |
| 236 |
|
* Compares the specified object with this set for equality. Returns |
| 237 |
< |
* <tt>true</tt> if the specified object is also a set, the two sets |
| 237 |
> |
* {@code true} if the specified object is also a set, the two sets |
| 238 |
|
* have the same size, and every member of the specified set is |
| 239 |
|
* contained in this set (or equivalently, every member of this set is |
| 240 |
|
* contained in the specified set). This definition ensures that the |
| 242 |
|
* set interface. |
| 243 |
|
* |
| 244 |
|
* @param o Object to be compared for equality with this set |
| 245 |
< |
* @return <tt>true</tt> if the specified Object is equal to this set |
| 245 |
> |
* @return {@code true} if the specified Object is equal to this set |
| 246 |
|
*/ |
| 247 |
|
public boolean equals(Object o) { |
| 248 |
|
// Override AbstractSet version to avoid calling size() |
| 268 |
|
* |
| 269 |
|
* @param c collection that defines which elements will be removed from |
| 270 |
|
* this set |
| 271 |
< |
* @return <tt>true</tt> if this set changed as a result of the call |
| 271 |
> |
* @return {@code true} if this set changed as a result of the call |
| 272 |
|
* |
| 273 |
|
* @throws ClassCastException if the types of one or more elements in this |
| 274 |
|
* set are incompatible with the specified collection |
| 275 |
|
* @throws NullPointerException if the specified collection, or any |
| 276 |
< |
* of its elements are <tt>null</tt> |
| 276 |
> |
* of its elements are {@code null} |
| 277 |
|
*/ |
| 278 |
|
public boolean removeAll(Collection<?> c) { |
| 279 |
|
// Override AbstractSet version to avoid unnecessary call to size() |
| 288 |
|
|
| 289 |
|
/** |
| 290 |
|
* Returns an element greater than or equal to the given element, or |
| 291 |
< |
* <tt>null</tt> if there is no such element. |
| 291 |
> |
* {@code null} if there is no such element. |
| 292 |
|
* |
| 293 |
|
* @param o the value to match |
| 294 |
|
* @return an element greater than or equal to given element, or |
| 295 |
< |
* <tt>null</tt> if there is no such element |
| 295 |
> |
* {@code null} if there is no such element |
| 296 |
|
* @throws ClassCastException if o cannot be compared with the elements |
| 297 |
|
* currently in the set |
| 298 |
< |
* @throws NullPointerException if o is <tt>null</tt> |
| 298 |
> |
* @throws NullPointerException if o is {@code null} |
| 299 |
|
*/ |
| 300 |
|
public E ceiling(E o) { |
| 301 |
|
return m.ceilingKey(o); |
| 303 |
|
|
| 304 |
|
/** |
| 305 |
|
* Returns an element strictly less than the given element, or |
| 306 |
< |
* <tt>null</tt> if there is no such element. |
| 306 |
> |
* {@code null} if there is no such element. |
| 307 |
|
* |
| 308 |
|
* @param o the value to match |
| 309 |
|
* @return the greatest element less than the given element, or |
| 310 |
< |
* <tt>null</tt> if there is no such element |
| 310 |
> |
* {@code null} if there is no such element |
| 311 |
|
* @throws ClassCastException if o cannot be compared with the elements |
| 312 |
|
* currently in the set |
| 313 |
< |
* @throws NullPointerException if o is <tt>null</tt> |
| 313 |
> |
* @throws NullPointerException if o is {@code null} |
| 314 |
|
*/ |
| 315 |
|
public E lower(E o) { |
| 316 |
|
return m.lowerKey(o); |
| 318 |
|
|
| 319 |
|
/** |
| 320 |
|
* Returns an element less than or equal to the given element, or |
| 321 |
< |
* <tt>null</tt> if there is no such element. |
| 321 |
> |
* {@code null} if there is no such element. |
| 322 |
|
* |
| 323 |
|
* @param o the value to match |
| 324 |
|
* @return the greatest element less than or equal to given |
| 325 |
< |
* element, or <tt>null</tt> if there is no such element |
| 325 |
> |
* element, or {@code null} if there is no such element |
| 326 |
|
* @throws ClassCastException if o cannot be compared with the elements |
| 327 |
|
* currently in the set |
| 328 |
< |
* @throws NullPointerException if o is <tt>null</tt> |
| 328 |
> |
* @throws NullPointerException if o is {@code null} |
| 329 |
|
*/ |
| 330 |
|
public E floor(E o) { |
| 331 |
|
return m.floorKey(o); |
| 333 |
|
|
| 334 |
|
/** |
| 335 |
|
* Returns an element strictly greater than the given element, or |
| 336 |
< |
* <tt>null</tt> if there is no such element. |
| 336 |
> |
* {@code null} if there is no such element. |
| 337 |
|
* |
| 338 |
|
* @param o the value to match |
| 339 |
|
* @return the least element greater than the given element, or |
| 340 |
< |
* <tt>null</tt> if there is no such element |
| 340 |
> |
* {@code null} if there is no such element |
| 341 |
|
* @throws ClassCastException if o cannot be compared with the elements |
| 342 |
|
* currently in the set |
| 343 |
< |
* @throws NullPointerException if o is <tt>null</tt> |
| 343 |
> |
* @throws NullPointerException if o is {@code null} |
| 344 |
|
*/ |
| 345 |
|
public E higher(E o) { |
| 346 |
|
return m.higherKey(o); |
| 349 |
|
/** |
| 350 |
|
* Retrieves and removes the first (lowest) element. |
| 351 |
|
* |
| 352 |
< |
* @return the least element, or <tt>null</tt> if empty |
| 352 |
> |
* @return the least element, or {@code null} if empty |
| 353 |
|
*/ |
| 354 |
|
public E pollFirst() { |
| 355 |
|
return m.pollFirstKey(); |
| 358 |
|
/** |
| 359 |
|
* Retrieves and removes the last (highest) element. |
| 360 |
|
* |
| 361 |
< |
* @return the last element, or <tt>null</tt> if empty |
| 361 |
> |
* @return the last element, or {@code null} if empty |
| 362 |
|
*/ |
| 363 |
|
public E pollLast() { |
| 364 |
|
return m.pollLastKey(); |
| 369 |
|
|
| 370 |
|
|
| 371 |
|
/** |
| 372 |
< |
* Returns the comparator used to order this set, or <tt>null</tt> |
| 372 |
> |
* Returns the comparator used to order this set, or {@code null} |
| 373 |
|
* if this set uses its elements natural ordering. |
| 374 |
|
* |
| 375 |
< |
* @return the comparator used to order this set, or <tt>null</tt> |
| 375 |
> |
* @return the comparator used to order this set, or {@code null} |
| 376 |
|
* if this set uses its elements natural ordering |
| 377 |
|
*/ |
| 378 |
|
public Comparator<? super E> comparator() { |
| 403 |
|
|
| 404 |
|
/** |
| 405 |
|
* Returns a view of the portion of this set whose elements range from |
| 406 |
< |
* <tt>fromElement</tt>, inclusive, to <tt>toElement</tt>, exclusive. (If |
| 407 |
< |
* <tt>fromElement</tt> and <tt>toElement</tt> are equal, the returned |
| 406 |
> |
* {@code fromElement}, inclusive, to {@code toElement}, exclusive. (If |
| 407 |
> |
* {@code fromElement} and {@code toElement} are equal, the returned |
| 408 |
|
* sorted set is empty.) The returned sorted set is backed by this set, |
| 409 |
|
* so changes in the returned sorted set are reflected in this set, and |
| 410 |
|
* vice-versa. |
| 411 |
|
* @param fromElement low endpoint (inclusive) of the subSet |
| 412 |
|
* @param toElement high endpoint (exclusive) of the subSet |
| 413 |
|
* @return a view of the portion of this set whose elements range from |
| 414 |
< |
* <tt>fromElement</tt>, inclusive, to <tt>toElement</tt>, |
| 414 |
> |
* {@code fromElement}, inclusive, to {@code toElement}, |
| 415 |
|
* exclusive |
| 416 |
< |
* @throws ClassCastException if <tt>fromElement</tt> and |
| 417 |
< |
* <tt>toElement</tt> cannot be compared to one another using |
| 416 |
> |
* @throws ClassCastException if {@code fromElement} and |
| 417 |
> |
* {@code toElement} cannot be compared to one another using |
| 418 |
|
* this set's comparator (or, if the set has no comparator, |
| 419 |
|
* using natural ordering) |
| 420 |
< |
* @throws IllegalArgumentException if <tt>fromElement</tt> is |
| 421 |
< |
* greater than <tt>toElement</tt> |
| 422 |
< |
* @throws NullPointerException if <tt>fromElement</tt> or |
| 423 |
< |
* <tt>toElement</tt> is <tt>null</tt> |
| 420 |
> |
* @throws IllegalArgumentException if {@code fromElement} is |
| 421 |
> |
* greater than {@code toElement} |
| 422 |
> |
* @throws NullPointerException if {@code fromElement} or |
| 423 |
> |
* {@code toElement} is {@code null} |
| 424 |
|
*/ |
| 425 |
|
public NavigableSet<E> subSet(E fromElement, E toElement) { |
| 426 |
|
return new ConcurrentSkipListSubSet<E>(m, fromElement, toElement); |
| 428 |
|
|
| 429 |
|
/** |
| 430 |
|
* Returns a view of the portion of this set whose elements are strictly |
| 431 |
< |
* less than <tt>toElement</tt>. The returned sorted set is backed by |
| 431 |
> |
* less than {@code toElement}. The returned sorted set is backed by |
| 432 |
|
* this set, so changes in the returned sorted set are reflected in this |
| 433 |
|
* set, and vice-versa. |
| 434 |
|
* @param toElement high endpoint (exclusive) of the headSet |
| 435 |
|
* @return a view of the portion of this set whose elements are strictly |
| 436 |
|
* less than toElement |
| 437 |
< |
* @throws ClassCastException if <tt>toElement</tt> is not compatible |
| 437 |
> |
* @throws ClassCastException if {@code toElement} is not compatible |
| 438 |
|
* with this set's comparator (or, if the set has no comparator, |
| 439 |
< |
* if <tt>toElement</tt> does not implement <tt>Comparable</tt>) |
| 440 |
< |
* @throws NullPointerException if <tt>toElement</tt> is <tt>null</tt> |
| 439 |
> |
* if {@code toElement} does not implement {@code Comparable}) |
| 440 |
> |
* @throws NullPointerException if {@code toElement} is {@code null} |
| 441 |
|
*/ |
| 442 |
|
public NavigableSet<E> headSet(E toElement) { |
| 443 |
|
return new ConcurrentSkipListSubSet<E>(m, null, toElement); |
| 446 |
|
|
| 447 |
|
/** |
| 448 |
|
* Returns a view of the portion of this set whose elements are |
| 449 |
< |
* greater than or equal to <tt>fromElement</tt>. The returned |
| 449 |
> |
* greater than or equal to {@code fromElement}. The returned |
| 450 |
|
* sorted set is backed by this set, so changes in the returned |
| 451 |
|
* sorted set are reflected in this set, and vice-versa. |
| 452 |
|
* @param fromElement low endpoint (inclusive) of the tailSet |
| 453 |
|
* @return a view of the portion of this set whose elements are |
| 454 |
< |
* greater than or equal to <tt>fromElement</tt> |
| 455 |
< |
* @throws ClassCastException if <tt>fromElement</tt> is not |
| 454 |
> |
* greater than or equal to {@code fromElement} |
| 455 |
> |
* @throws ClassCastException if {@code fromElement} is not |
| 456 |
|
* compatible with this set's comparator (or, if the set has no |
| 457 |
< |
* comparator, if <tt>fromElement</tt> does not implement |
| 458 |
< |
* <tt>Comparable</tt>) |
| 459 |
< |
* @throws NullPointerException if <tt>fromElement</tt> is <tt>null</tt> |
| 457 |
> |
* comparator, if {@code fromElement} does not implement |
| 458 |
> |
* {@code Comparable}) |
| 459 |
> |
* @throws NullPointerException if {@code fromElement} is {@code null} |
| 460 |
|
*/ |
| 461 |
|
public NavigableSet<E> tailSet(E fromElement) { |
| 462 |
|
return new ConcurrentSkipListSubSet<E>(m, fromElement, null); |
| 469 |
|
* underlying sets, differing in that elements outside their range are |
| 470 |
|
* ignored, and attempts to add elements outside their ranges result |
| 471 |
|
* in {@link IllegalArgumentException}. Instances of this class are |
| 472 |
< |
* constructed only using the <tt>subSet</tt>, <tt>headSet</tt>, and |
| 473 |
< |
* <tt>tailSet</tt> methods of their underlying sets. |
| 472 |
> |
* constructed only using the {@code subSet}, {@code headSet}, and |
| 473 |
> |
* {@code tailSet} methods of their underlying sets. |
| 474 |
|
*/ |
| 475 |
|
static class ConcurrentSkipListSubSet<E> |
| 476 |
|
extends AbstractSet<E> |
| 483 |
|
|
| 484 |
|
/** |
| 485 |
|
* Creates a new submap. |
| 486 |
< |
* @param fromElement inclusive least value, or <tt>null</tt> if from start |
| 487 |
< |
* @param toElement exclusive upper bound or <tt>null</tt> if to end |
| 486 |
> |
* @param fromElement inclusive least value, or {@code null} if from start |
| 487 |
> |
* @param toElement exclusive upper bound or {@code null} if to end |
| 488 |
|
* @throws IllegalArgumentException if fromElement and toElement |
| 489 |
|
* non-null and fromElement greater than toElement |
| 490 |
|
*/ |
