1 /*
2 * Copyright (c) 1997, 2018, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation. Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25
26 package java.util;
27
28 import java.io.Serializable;
29 import java.util.function.BiConsumer;
30 import java.util.function.BiFunction;
31 import java.util.function.Consumer;
32
33 /**
34 * A Red-Black tree based {@link NavigableMap} implementation.
35 * The map is sorted according to the {@linkplain Comparable natural
36 * ordering} of its keys, or by a {@link Comparator} provided at map
37 * creation time, depending on which constructor is used.
38 *
39 * <p>This implementation provides guaranteed log(n) time cost for the
40 * {@code containsKey}, {@code get}, {@code put} and {@code remove}
41 * operations. Algorithms are adaptations of those in Cormen, Leiserson, and
42 * Rivest's <em>Introduction to Algorithms</em>.
43 *
44 * <p>Note that the ordering maintained by a tree map, like any sorted map, and
45 * whether or not an explicit comparator is provided, must be <em>consistent
46 * with {@code equals}</em> if this sorted map is to correctly implement the
47 * {@code Map} interface. (See {@code Comparable} or {@code Comparator} for a
48 * precise definition of <em>consistent with equals</em>.) This is so because
49 * the {@code Map} interface is defined in terms of the {@code equals}
50 * operation, but a sorted map performs all key comparisons using its {@code
51 * compareTo} (or {@code compare}) method, so two keys that are deemed equal by
52 * this method are, from the standpoint of the sorted map, equal. The behavior
53 * of a sorted map <em>is</em> well-defined even if its ordering is
54 * inconsistent with {@code equals}; it just fails to obey the general contract
55 * of the {@code Map} interface.
56 *
57 * <p><strong>Note that this implementation is not synchronized.</strong>
58 * If multiple threads access a map concurrently, and at least one of the
59 * threads modifies the map structurally, it <em>must</em> be synchronized
60 * externally. (A structural modification is any operation that adds or
61 * deletes one or more mappings; merely changing the value associated
62 * with an existing key is not a structural modification.) This is
63 * typically accomplished by synchronizing on some object that naturally
64 * encapsulates the map.
65 * If no such object exists, the map should be "wrapped" using the
66 * {@link Collections#synchronizedSortedMap Collections.synchronizedSortedMap}
67 * method. This is best done at creation time, to prevent accidental
68 * unsynchronized access to the map: <pre>
69 * SortedMap m = Collections.synchronizedSortedMap(new TreeMap(...));</pre>
70 *
71 * <p>The iterators returned by the {@code iterator} method of the collections
72 * returned by all of this class's "collection view methods" are
73 * <em>fail-fast</em>: if the map is structurally modified at any time after
74 * the iterator is created, in any way except through the iterator's own
75 * {@code remove} method, the iterator will throw a {@link
76 * ConcurrentModificationException}. Thus, in the face of concurrent
77 * modification, the iterator fails quickly and cleanly, rather than risking
78 * arbitrary, non-deterministic behavior at an undetermined time in the future.
79 *
80 * <p>Note that the fail-fast behavior of an iterator cannot be guaranteed
81 * as it is, generally speaking, impossible to make any hard guarantees in the
82 * presence of unsynchronized concurrent modification. Fail-fast iterators
83 * throw {@code ConcurrentModificationException} on a best-effort basis.
84 * Therefore, it would be wrong to write a program that depended on this
85 * exception for its correctness: <em>the fail-fast behavior of iterators
86 * should be used only to detect bugs.</em>
87 *
88 * <p>All {@code Map.Entry} pairs returned by methods in this class
89 * and its views represent snapshots of mappings at the time they were
90 * produced. They do <strong>not</strong> support the {@code Entry.setValue}
91 * method. (Note however that it is possible to change mappings in the
92 * associated map using {@code put}.)
93 *
94 * <p>This class is a member of the
95 * <a href="{@docRoot}/java.base/java/util/package-summary.html#CollectionsFramework">
96 * Java Collections Framework</a>.
97 *
98 * @param <K> the type of keys maintained by this map
99 * @param <V> the type of mapped values
100 *
101 * @author Josh Bloch and Doug Lea
102 * @see Map
103 * @see HashMap
104 * @see Hashtable
105 * @see Comparable
106 * @see Comparator
107 * @see Collection
108 * @since 1.2
109 */
110
111 public class TreeMap<K,V>
112 extends AbstractMap<K,V>
113 implements NavigableMap<K,V>, Cloneable, java.io.Serializable
114 {
115 /**
116 * The comparator used to maintain order in this tree map, or
117 * null if it uses the natural ordering of its keys.
118 *
119 * @serial
120 */
121 private final Comparator<? super K> comparator;
122
123 private transient Entry<K,V> root;
124
125 /**
126 * The number of entries in the tree
127 */
128 private transient int size = 0;
129
130 /**
131 * The number of structural modifications to the tree.
132 */
133 private transient int modCount = 0;
134
135 /**
136 * Constructs a new, empty tree map, using the natural ordering of its
137 * keys. All keys inserted into the map must implement the {@link
138 * Comparable} interface. Furthermore, all such keys must be
139 * <em>mutually comparable</em>: {@code k1.compareTo(k2)} must not throw
140 * a {@code ClassCastException} for any keys {@code k1} and
141 * {@code k2} in the map. If the user attempts to put a key into the
142 * map that violates this constraint (for example, the user attempts to
143 * put a string key into a map whose keys are integers), the
144 * {@code put(Object key, Object value)} call will throw a
145 * {@code ClassCastException}.
146 */
147 public TreeMap() {
148 comparator = null;
149 }
150
151 /**
152 * Constructs a new, empty tree map, ordered according to the given
153 * comparator. All keys inserted into the map must be <em>mutually
154 * comparable</em> by the given comparator: {@code comparator.compare(k1,
155 * k2)} must not throw a {@code ClassCastException} for any keys
156 * {@code k1} and {@code k2} in the map. If the user attempts to put
157 * a key into the map that violates this constraint, the {@code put(Object
158 * key, Object value)} call will throw a
159 * {@code ClassCastException}.
160 *
161 * @param comparator the comparator that will be used to order this map.
162 * If {@code null}, the {@linkplain Comparable natural
163 * ordering} of the keys will be used.
164 */
165 public TreeMap(Comparator<? super K> comparator) {
166 this.comparator = comparator;
167 }
168
169 /**
170 * Constructs a new tree map containing the same mappings as the given
171 * map, ordered according to the <em>natural ordering</em> of its keys.
172 * All keys inserted into the new map must implement the {@link
173 * Comparable} interface. Furthermore, all such keys must be
174 * <em>mutually comparable</em>: {@code k1.compareTo(k2)} must not throw
175 * a {@code ClassCastException} for any keys {@code k1} and
176 * {@code k2} in the map. This method runs in n*log(n) time.
177 *
178 * @param m the map whose mappings are to be placed in this map
179 * @throws ClassCastException if the keys in m are not {@link Comparable},
180 * or are not mutually comparable
181 * @throws NullPointerException if the specified map is null
182 */
183 public TreeMap(Map<? extends K, ? extends V> m) {
184 comparator = null;
185 putAll(m);
186 }
187
188 /**
189 * Constructs a new tree map containing the same mappings and
190 * using the same ordering as the specified sorted map. This
191 * method runs in linear time.
192 *
193 * @param m the sorted map whose mappings are to be placed in this map,
194 * and whose comparator is to be used to sort this map
195 * @throws NullPointerException if the specified map is null
196 */
197 public TreeMap(SortedMap<K, ? extends V> m) {
198 comparator = m.comparator();
199 try {
200 buildFromSorted(m.size(), m.entrySet().iterator(), null, null);
201 } catch (java.io.IOException | ClassNotFoundException cannotHappen) {
202 }
203 }
204
205
206 // Query Operations
207
208 /**
209 * Returns the number of key-value mappings in this map.
210 *
211 * @return the number of key-value mappings in this map
212 */
213 public int size() {
214 return size;
215 }
216
217 /**
218 * Returns {@code true} if this map contains a mapping for the specified
219 * key.
220 *
221 * @param key key whose presence in this map is to be tested
222 * @return {@code true} if this map contains a mapping for the
223 * specified key
224 * @throws ClassCastException if the specified key cannot be compared
225 * with the keys currently in the map
226 * @throws NullPointerException if the specified key is null
227 * and this map uses natural ordering, or its comparator
228 * does not permit null keys
229 */
230 public boolean containsKey(Object key) {
231 return getEntry(key) != null;
232 }
233
234 /**
235 * Returns {@code true} if this map maps one or more keys to the
236 * specified value. More formally, returns {@code true} if and only if
237 * this map contains at least one mapping to a value {@code v} such
238 * that {@code (value==null ? v==null : value.equals(v))}. This
239 * operation will probably require time linear in the map size for
240 * most implementations.
241 *
242 * @param value value whose presence in this map is to be tested
243 * @return {@code true} if a mapping to {@code value} exists;
244 * {@code false} otherwise
245 * @since 1.2
246 */
247 public boolean containsValue(Object value) {
248 for (Entry<K,V> e = getFirstEntry(); e != null; e = successor(e))
249 if (valEquals(value, e.value))
250 return true;
251 return false;
252 }
253
254 /**
255 * Returns the value to which the specified key is mapped,
256 * or {@code null} if this map contains no mapping for the key.
257 *
258 * <p>More formally, if this map contains a mapping from a key
259 * {@code k} to a value {@code v} such that {@code key} compares
260 * equal to {@code k} according to the map's ordering, then this
261 * method returns {@code v}; otherwise it returns {@code null}.
262 * (There can be at most one such mapping.)
263 *
264 * <p>A return value of {@code null} does not <em>necessarily</em>
265 * indicate that the map contains no mapping for the key; it's also
266 * possible that the map explicitly maps the key to {@code null}.
267 * The {@link #containsKey containsKey} operation may be used to
268 * distinguish these two cases.
269 *
270 * @throws ClassCastException if the specified key cannot be compared
271 * with the keys currently in the map
272 * @throws NullPointerException if the specified key is null
273 * and this map uses natural ordering, or its comparator
274 * does not permit null keys
275 */
276 public V get(Object key) {
277 Entry<K,V> p = getEntry(key);
278 return (p==null ? null : p.value);
279 }
280
281 public Comparator<? super K> comparator() {
282 return comparator;
283 }
284
285 /**
286 * @throws NoSuchElementException {@inheritDoc}
287 */
288 public K firstKey() {
289 return key(getFirstEntry());
290 }
291
292 /**
293 * @throws NoSuchElementException {@inheritDoc}
294 */
295 public K lastKey() {
296 return key(getLastEntry());
297 }
298
299 /**
300 * Copies all of the mappings from the specified map to this map.
301 * These mappings replace any mappings that this map had for any
302 * of the keys currently in the specified map.
303 *
304 * @param map mappings to be stored in this map
305 * @throws ClassCastException if the class of a key or value in
306 * the specified map prevents it from being stored in this map
307 * @throws NullPointerException if the specified map is null or
308 * the specified map contains a null key and this map does not
309 * permit null keys
310 */
311 public void putAll(Map<? extends K, ? extends V> map) {
312 int mapSize = map.size();
313 if (size==0 && mapSize!=0 && map instanceof SortedMap) {
314 Comparator<?> c = ((SortedMap<?,?>)map).comparator();
315 if (c == comparator || (c != null && c.equals(comparator))) {
316 ++modCount;
317 try {
318 buildFromSorted(mapSize, map.entrySet().iterator(),
319 null, null);
320 } catch (java.io.IOException | ClassNotFoundException cannotHappen) {
321 }
322 return;
323 }
324 }
325 super.putAll(map);
326 }
327
328 /**
329 * Returns this map's entry for the given key, or {@code null} if the map
330 * does not contain an entry for the key.
331 *
332 * @return this map's entry for the given key, or {@code null} if the map
333 * does not contain an entry for the key
334 * @throws ClassCastException if the specified key cannot be compared
335 * with the keys currently in the map
336 * @throws NullPointerException if the specified key is null
337 * and this map uses natural ordering, or its comparator
338 * does not permit null keys
339 */
340 final Entry<K,V> getEntry(Object key) {
341 // Offload comparator-based version for sake of performance
342 if (comparator != null)
343 return getEntryUsingComparator(key);
344 if (key == null)
345 throw new NullPointerException();
346 @SuppressWarnings("unchecked")
347 Comparable<? super K> k = (Comparable<? super K>) key;
348 Entry<K,V> p = root;
349 while (p != null) {
350 int cmp = k.compareTo(p.key);
351 if (cmp < 0)
352 p = p.left;
353 else if (cmp > 0)
354 p = p.right;
355 else
356 return p;
357 }
358 return null;
359 }
360
361 /**
362 * Version of getEntry using comparator. Split off from getEntry
363 * for performance. (This is not worth doing for most methods,
364 * that are less dependent on comparator performance, but is
365 * worthwhile here.)
366 */
367 final Entry<K,V> getEntryUsingComparator(Object key) {
368 @SuppressWarnings("unchecked")
369 K k = (K) key;
370 Comparator<? super K> cpr = comparator;
371 if (cpr != null) {
372 Entry<K,V> p = root;
373 while (p != null) {
374 int cmp = cpr.compare(k, p.key);
375 if (cmp < 0)
376 p = p.left;
377 else if (cmp > 0)
378 p = p.right;
379 else
380 return p;
381 }
382 }
383 return null;
384 }
385
386 /**
387 * Gets the entry corresponding to the specified key; if no such entry
388 * exists, returns the entry for the least key greater than the specified
389 * key; if no such entry exists (i.e., the greatest key in the Tree is less
390 * than the specified key), returns {@code null}.
391 */
392 final Entry<K,V> getCeilingEntry(K key) {
393 Entry<K,V> p = root;
394 while (p != null) {
395 int cmp = compare(key, p.key);
396 if (cmp < 0) {
397 if (p.left != null)
398 p = p.left;
399 else
400 return p;
401 } else if (cmp > 0) {
402 if (p.right != null) {
403 p = p.right;
404 } else {
405 Entry<K,V> parent = p.parent;
406 Entry<K,V> ch = p;
407 while (parent != null && ch == parent.right) {
408 ch = parent;
409 parent = parent.parent;
410 }
411 return parent;
412 }
413 } else
414 return p;
415 }
416 return null;
417 }
418
419 /**
420 * Gets the entry corresponding to the specified key; if no such entry
421 * exists, returns the entry for the greatest key less than the specified
422 * key; if no such entry exists, returns {@code null}.
423 */
424 final Entry<K,V> getFloorEntry(K key) {
425 Entry<K,V> p = root;
426 while (p != null) {
427 int cmp = compare(key, p.key);
428 if (cmp > 0) {
429 if (p.right != null)
430 p = p.right;
431 else
432 return p;
433 } else if (cmp < 0) {
434 if (p.left != null) {
435 p = p.left;
436 } else {
437 Entry<K,V> parent = p.parent;
438 Entry<K,V> ch = p;
439 while (parent != null && ch == parent.left) {
440 ch = parent;
441 parent = parent.parent;
442 }
443 return parent;
444 }
445 } else
446 return p;
447
448 }
449 return null;
450 }
451
452 /**
453 * Gets the entry for the least key greater than the specified
454 * key; if no such entry exists, returns the entry for the least
455 * key greater than the specified key; if no such entry exists
456 * returns {@code null}.
457 */
458 final Entry<K,V> getHigherEntry(K key) {
459 Entry<K,V> p = root;
460 while (p != null) {
461 int cmp = compare(key, p.key);
462 if (cmp < 0) {
463 if (p.left != null)
464 p = p.left;
465 else
466 return p;
467 } else {
468 if (p.right != null) {
469 p = p.right;
470 } else {
471 Entry<K,V> parent = p.parent;
472 Entry<K,V> ch = p;
473 while (parent != null && ch == parent.right) {
474 ch = parent;
475 parent = parent.parent;
476 }
477 return parent;
478 }
479 }
480 }
481 return null;
482 }
483
484 /**
485 * Returns the entry for the greatest key less than the specified key; if
486 * no such entry exists (i.e., the least key in the Tree is greater than
487 * the specified key), returns {@code null}.
488 */
489 final Entry<K,V> getLowerEntry(K key) {
490 Entry<K,V> p = root;
491 while (p != null) {
492 int cmp = compare(key, p.key);
493 if (cmp > 0) {
494 if (p.right != null)
495 p = p.right;
496 else
497 return p;
498 } else {
499 if (p.left != null) {
500 p = p.left;
501 } else {
502 Entry<K,V> parent = p.parent;
503 Entry<K,V> ch = p;
504 while (parent != null && ch == parent.left) {
505 ch = parent;
506 parent = parent.parent;
507 }
508 return parent;
509 }
510 }
511 }
512 return null;
513 }
514
515 /**
516 * Associates the specified value with the specified key in this map.
517 * If the map previously contained a mapping for the key, the old
518 * value is replaced.
519 *
520 * @param key key with which the specified value is to be associated
521 * @param value value to be associated with the specified key
522 *
523 * @return the previous value associated with {@code key}, or
524 * {@code null} if there was no mapping for {@code key}.
525 * (A {@code null} return can also indicate that the map
526 * previously associated {@code null} with {@code key}.)
527 * @throws ClassCastException if the specified key cannot be compared
528 * with the keys currently in the map
529 * @throws NullPointerException if the specified key is null
530 * and this map uses natural ordering, or its comparator
531 * does not permit null keys
532 */
533 public V put(K key, V value) {
534 Entry<K,V> t = root;
535 if (t == null) {
536 compare(key, key); // type (and possibly null) check
537
538 root = new Entry<>(key, value, null);
539 size = 1;
540 modCount++;
541 return null;
542 }
543 int cmp;
544 Entry<K,V> parent;
545 // split comparator and comparable paths
546 Comparator<? super K> cpr = comparator;
547 if (cpr != null) {
548 do {
549 parent = t;
550 cmp = cpr.compare(key, t.key);
551 if (cmp < 0)
552 t = t.left;
553 else if (cmp > 0)
554 t = t.right;
555 else
556 return t.setValue(value);
557 } while (t != null);
558 }
559 else {
560 if (key == null)
561 throw new NullPointerException();
562 @SuppressWarnings("unchecked")
563 Comparable<? super K> k = (Comparable<? super K>) key;
564 do {
565 parent = t;
566 cmp = k.compareTo(t.key);
567 if (cmp < 0)
568 t = t.left;
569 else if (cmp > 0)
570 t = t.right;
571 else
572 return t.setValue(value);
573 } while (t != null);
574 }
575 Entry<K,V> e = new Entry<>(key, value, parent);
576 if (cmp < 0)
577 parent.left = e;
578 else
579 parent.right = e;
580 fixAfterInsertion(e);
581 size++;
582 modCount++;
583 return null;
584 }
585
586 /**
587 * Removes the mapping for this key from this TreeMap if present.
588 *
589 * @param key key for which mapping should be removed
590 * @return the previous value associated with {@code key}, or
591 * {@code null} if there was no mapping for {@code key}.
592 * (A {@code null} return can also indicate that the map
593 * previously associated {@code null} with {@code key}.)
594 * @throws ClassCastException if the specified key cannot be compared
595 * with the keys currently in the map
596 * @throws NullPointerException if the specified key is null
597 * and this map uses natural ordering, or its comparator
598 * does not permit null keys
599 */
600 public V remove(Object key) {
601 Entry<K,V> p = getEntry(key);
602 if (p == null)
603 return null;
604
605 V oldValue = p.value;
606 deleteEntry(p);
607 return oldValue;
608 }
609
610 /**
611 * Removes all of the mappings from this map.
612 * The map will be empty after this call returns.
613 */
614 public void clear() {
615 modCount++;
616 size = 0;
617 root = null;
618 }
619
620 /**
621 * Returns a shallow copy of this {@code TreeMap} instance. (The keys and
622 * values themselves are not cloned.)
623 *
624 * @return a shallow copy of this map
625 */
626 public Object clone() {
627 TreeMap<?,?> clone;
628 try {
629 clone = (TreeMap<?,?>) super.clone();
630 } catch (CloneNotSupportedException e) {
631 throw new InternalError(e);
632 }
633
634 // Put clone into "virgin" state (except for comparator)
635 clone.root = null;
636 clone.size = 0;
637 clone.modCount = 0;
638 clone.entrySet = null;
639 clone.navigableKeySet = null;
640 clone.descendingMap = null;
641
642 // Initialize clone with our mappings
643 try {
644 clone.buildFromSorted(size, entrySet().iterator(), null, null);
645 } catch (java.io.IOException | ClassNotFoundException cannotHappen) {
646 }
647
648 return clone;
649 }
650
651 // NavigableMap API methods
652
653 /**
654 * @since 1.6
655 */
656 public Map.Entry<K,V> firstEntry() {
657 return exportEntry(getFirstEntry());
658 }
659
660 /**
661 * @since 1.6
662 */
663 public Map.Entry<K,V> lastEntry() {
664 return exportEntry(getLastEntry());
665 }
666
667 /**
668 * @since 1.6
669 */
670 public Map.Entry<K,V> pollFirstEntry() {
671 Entry<K,V> p = getFirstEntry();
672 Map.Entry<K,V> result = exportEntry(p);
673 if (p != null)
674 deleteEntry(p);
675 return result;
676 }
677
678 /**
679 * @since 1.6
680 */
681 public Map.Entry<K,V> pollLastEntry() {
682 Entry<K,V> p = getLastEntry();
683 Map.Entry<K,V> result = exportEntry(p);
684 if (p != null)
685 deleteEntry(p);
686 return result;
687 }
688
689 /**
690 * @throws ClassCastException {@inheritDoc}
691 * @throws NullPointerException if the specified key is null
692 * and this map uses natural ordering, or its comparator
693 * does not permit null keys
694 * @since 1.6
695 */
696 public Map.Entry<K,V> lowerEntry(K key) {
697 return exportEntry(getLowerEntry(key));
698 }
699
700 /**
701 * @throws ClassCastException {@inheritDoc}
702 * @throws NullPointerException if the specified key is null
703 * and this map uses natural ordering, or its comparator
704 * does not permit null keys
705 * @since 1.6
706 */
707 public K lowerKey(K key) {
708 return keyOrNull(getLowerEntry(key));
709 }
710
711 /**
712 * @throws ClassCastException {@inheritDoc}
713 * @throws NullPointerException if the specified key is null
714 * and this map uses natural ordering, or its comparator
715 * does not permit null keys
716 * @since 1.6
717 */
718 public Map.Entry<K,V> floorEntry(K key) {
719 return exportEntry(getFloorEntry(key));
720 }
721
722 /**
723 * @throws ClassCastException {@inheritDoc}
724 * @throws NullPointerException if the specified key is null
725 * and this map uses natural ordering, or its comparator
726 * does not permit null keys
727 * @since 1.6
728 */
729 public K floorKey(K key) {
730 return keyOrNull(getFloorEntry(key));
731 }
732
733 /**
734 * @throws ClassCastException {@inheritDoc}
735 * @throws NullPointerException if the specified key is null
736 * and this map uses natural ordering, or its comparator
737 * does not permit null keys
738 * @since 1.6
739 */
740 public Map.Entry<K,V> ceilingEntry(K key) {
741 return exportEntry(getCeilingEntry(key));
742 }
743
744 /**
745 * @throws ClassCastException {@inheritDoc}
746 * @throws NullPointerException if the specified key is null
747 * and this map uses natural ordering, or its comparator
748 * does not permit null keys
749 * @since 1.6
750 */
751 public K ceilingKey(K key) {
752 return keyOrNull(getCeilingEntry(key));
753 }
754
755 /**
756 * @throws ClassCastException {@inheritDoc}
757 * @throws NullPointerException if the specified key is null
758 * and this map uses natural ordering, or its comparator
759 * does not permit null keys
760 * @since 1.6
761 */
762 public Map.Entry<K,V> higherEntry(K key) {
763 return exportEntry(getHigherEntry(key));
764 }
765
766 /**
767 * @throws ClassCastException {@inheritDoc}
768 * @throws NullPointerException if the specified key is null
769 * and this map uses natural ordering, or its comparator
770 * does not permit null keys
771 * @since 1.6
772 */
773 public K higherKey(K key) {
774 return keyOrNull(getHigherEntry(key));
775 }
776
777 // Views
778
779 /**
780 * Fields initialized to contain an instance of the entry set view
781 * the first time this view is requested. Views are stateless, so
782 * there's no reason to create more than one.
783 */
784 private transient EntrySet entrySet;
785 private transient KeySet<K> navigableKeySet;
786 private transient NavigableMap<K,V> descendingMap;
787
788 /**
789 * Returns a {@link Set} view of the keys contained in this map.
790 *
791 * <p>The set's iterator returns the keys in ascending order.
792 * The set's spliterator is
793 * <em><a href="Spliterator.html#binding">late-binding</a></em>,
794 * <em>fail-fast</em>, and additionally reports {@link Spliterator#SORTED}
795 * and {@link Spliterator#ORDERED} with an encounter order that is ascending
796 * key order. The spliterator's comparator (see
797 * {@link java.util.Spliterator#getComparator()}) is {@code null} if
798 * the tree map's comparator (see {@link #comparator()}) is {@code null}.
799 * Otherwise, the spliterator's comparator is the same as or imposes the
800 * same total ordering as the tree map's comparator.
801 *
802 * <p>The set is backed by the map, so changes to the map are
803 * reflected in the set, and vice-versa. If the map is modified
804 * while an iteration over the set is in progress (except through
805 * the iterator's own {@code remove} operation), the results of
806 * the iteration are undefined. The set supports element removal,
807 * which removes the corresponding mapping from the map, via the
808 * {@code Iterator.remove}, {@code Set.remove},
809 * {@code removeAll}, {@code retainAll}, and {@code clear}
810 * operations. It does not support the {@code add} or {@code addAll}
811 * operations.
812 */
813 public Set<K> keySet() {
814 return navigableKeySet();
815 }
816
817 /**
818 * @since 1.6
819 */
820 public NavigableSet<K> navigableKeySet() {
821 KeySet<K> nks = navigableKeySet;
822 return (nks != null) ? nks : (navigableKeySet = new KeySet<>(this));
823 }
824
825 /**
826 * @since 1.6
827 */
828 public NavigableSet<K> descendingKeySet() {
829 return descendingMap().navigableKeySet();
830 }
831
832 /**
833 * Returns a {@link Collection} view of the values contained in this map.
834 *
835 * <p>The collection's iterator returns the values in ascending order
836 * of the corresponding keys. The collection's spliterator is
837 * <em><a href="Spliterator.html#binding">late-binding</a></em>,
838 * <em>fail-fast</em>, and additionally reports {@link Spliterator#ORDERED}
839 * with an encounter order that is ascending order of the corresponding
840 * keys.
841 *
842 * <p>The collection is backed by the map, so changes to the map are
843 * reflected in the collection, and vice-versa. If the map is
844 * modified while an iteration over the collection is in progress
845 * (except through the iterator's own {@code remove} operation),
846 * the results of the iteration are undefined. The collection
847 * supports element removal, which removes the corresponding
848 * mapping from the map, via the {@code Iterator.remove},
849 * {@code Collection.remove}, {@code removeAll},
850 * {@code retainAll} and {@code clear} operations. It does not
851 * support the {@code add} or {@code addAll} operations.
852 */
853 public Collection<V> values() {
854 Collection<V> vs = values;
855 if (vs == null) {
856 vs = new Values();
857 values = vs;
858 }
859 return vs;
860 }
861
862 /**
863 * Returns a {@link Set} view of the mappings contained in this map.
864 *
865 * <p>The set's iterator returns the entries in ascending key order. The
866 * set's spliterator is
867 * <em><a href="Spliterator.html#binding">late-binding</a></em>,
868 * <em>fail-fast</em>, and additionally reports {@link Spliterator#SORTED} and
869 * {@link Spliterator#ORDERED} with an encounter order that is ascending key
870 * order.
871 *
872 * <p>The set is backed by the map, so changes to the map are
873 * reflected in the set, and vice-versa. If the map is modified
874 * while an iteration over the set is in progress (except through
875 * the iterator's own {@code remove} operation, or through the
876 * {@code setValue} operation on a map entry returned by the
877 * iterator) the results of the iteration are undefined. The set
878 * supports element removal, which removes the corresponding
879 * mapping from the map, via the {@code Iterator.remove},
880 * {@code Set.remove}, {@code removeAll}, {@code retainAll} and
881 * {@code clear} operations. It does not support the
882 * {@code add} or {@code addAll} operations.
883 */
884 public Set<Map.Entry<K,V>> entrySet() {
885 EntrySet es = entrySet;
886 return (es != null) ? es : (entrySet = new EntrySet());
887 }
888
889 /**
890 * @since 1.6
891 */
892 public NavigableMap<K, V> descendingMap() {
893 NavigableMap<K, V> km = descendingMap;
894 return (km != null) ? km :
895 (descendingMap = new DescendingSubMap<>(this,
896 true, null, true,
897 true, null, true));
898 }
899
900 /**
901 * @throws ClassCastException {@inheritDoc}
902 * @throws NullPointerException if {@code fromKey} or {@code toKey} is
903 * null and this map uses natural ordering, or its comparator
904 * does not permit null keys
905 * @throws IllegalArgumentException {@inheritDoc}
906 * @since 1.6
907 */
908 public NavigableMap<K,V> subMap(K fromKey, boolean fromInclusive,
909 K toKey, boolean toInclusive) {
910 return new AscendingSubMap<>(this,
911 false, fromKey, fromInclusive,
912 false, toKey, toInclusive);
913 }
914
915 /**
916 * @throws ClassCastException {@inheritDoc}
917 * @throws NullPointerException if {@code toKey} is null
918 * and this map uses natural ordering, or its comparator
919 * does not permit null keys
920 * @throws IllegalArgumentException {@inheritDoc}
921 * @since 1.6
922 */
923 public NavigableMap<K,V> headMap(K toKey, boolean inclusive) {
924 return new AscendingSubMap<>(this,
925 true, null, true,
926 false, toKey, inclusive);
927 }
928
929 /**
930 * @throws ClassCastException {@inheritDoc}
931 * @throws NullPointerException if {@code fromKey} is null
932 * and this map uses natural ordering, or its comparator
933 * does not permit null keys
934 * @throws IllegalArgumentException {@inheritDoc}
935 * @since 1.6
936 */
937 public NavigableMap<K,V> tailMap(K fromKey, boolean inclusive) {
938 return new AscendingSubMap<>(this,
939 false, fromKey, inclusive,
940 true, null, true);
941 }
942
943 /**
944 * @throws ClassCastException {@inheritDoc}
945 * @throws NullPointerException if {@code fromKey} or {@code toKey} is
946 * null and this map uses natural ordering, or its comparator
947 * does not permit null keys
948 * @throws IllegalArgumentException {@inheritDoc}
949 */
950 public SortedMap<K,V> subMap(K fromKey, K toKey) {
951 return subMap(fromKey, true, toKey, false);
952 }
953
954 /**
955 * @throws ClassCastException {@inheritDoc}
956 * @throws NullPointerException if {@code toKey} is null
957 * and this map uses natural ordering, or its comparator
958 * does not permit null keys
959 * @throws IllegalArgumentException {@inheritDoc}
960 */
961 public SortedMap<K,V> headMap(K toKey) {
962 return headMap(toKey, false);
963 }
964
965 /**
966 * @throws ClassCastException {@inheritDoc}
967 * @throws NullPointerException if {@code fromKey} is null
968 * and this map uses natural ordering, or its comparator
969 * does not permit null keys
970 * @throws IllegalArgumentException {@inheritDoc}
971 */
972 public SortedMap<K,V> tailMap(K fromKey) {
973 return tailMap(fromKey, true);
974 }
975
976 @Override
977 public boolean replace(K key, V oldValue, V newValue) {
978 Entry<K,V> p = getEntry(key);
979 if (p!=null && Objects.equals(oldValue, p.value)) {
980 p.value = newValue;
981 return true;
982 }
983 return false;
984 }
985
986 @Override
987 public V replace(K key, V value) {
988 Entry<K,V> p = getEntry(key);
989 if (p!=null) {
990 V oldValue = p.value;
991 p.value = value;
992 return oldValue;
993 }
994 return null;
995 }
996
997 @Override
998 public void forEach(BiConsumer<? super K, ? super V> action) {
999 Objects.requireNonNull(action);
1000 int expectedModCount = modCount;
1001 for (Entry<K, V> e = getFirstEntry(); e != null; e = successor(e)) {
1002 action.accept(e.key, e.value);
1003
1004 if (expectedModCount != modCount) {
1005 throw new ConcurrentModificationException();
1006 }
1007 }
1008 }
1009
1010 @Override
1011 public void replaceAll(BiFunction<? super K, ? super V, ? extends V> function) {
1012 Objects.requireNonNull(function);
1013 int expectedModCount = modCount;
1014
1015 for (Entry<K, V> e = getFirstEntry(); e != null; e = successor(e)) {
1016 e.value = function.apply(e.key, e.value);
1017
1018 if (expectedModCount != modCount) {
1019 throw new ConcurrentModificationException();
1020 }
1021 }
1022 }
1023
1024 // View class support
1025
1026 class Values extends AbstractCollection<V> {
1027 public Iterator<V> iterator() {
1028 return new ValueIterator(getFirstEntry());
1029 }
1030
1031 public int size() {
1032 return TreeMap.this.size();
1033 }
1034
1035 public boolean contains(Object o) {
1036 return TreeMap.this.containsValue(o);
1037 }
1038
1039 public boolean remove(Object o) {
1040 for (Entry<K,V> e = getFirstEntry(); e != null; e = successor(e)) {
1041 if (valEquals(e.getValue(), o)) {
1042 deleteEntry(e);
1043 return true;
1044 }
1045 }
1046 return false;
1047 }
1048
1049 public void clear() {
1050 TreeMap.this.clear();
1051 }
1052
1053 public Spliterator<V> spliterator() {
1054 return new ValueSpliterator<>(TreeMap.this, null, null, 0, -1, 0);
1055 }
1056 }
1057
1058 class EntrySet extends AbstractSet<Map.Entry<K,V>> {
1059 public Iterator<Map.Entry<K,V>> iterator() {
1060 return new EntryIterator(getFirstEntry());
1061 }
1062
1063 public boolean contains(Object o) {
1064 if (!(o instanceof Map.Entry))
1065 return false;
1066 Map.Entry<?,?> entry = (Map.Entry<?,?>) o;
1067 Object value = entry.getValue();
1068 Entry<K,V> p = getEntry(entry.getKey());
1069 return p != null && valEquals(p.getValue(), value);
1070 }
1071
1072 public boolean remove(Object o) {
1073 if (!(o instanceof Map.Entry))
1074 return false;
1075 Map.Entry<?,?> entry = (Map.Entry<?,?>) o;
1076 Object value = entry.getValue();
1077 Entry<K,V> p = getEntry(entry.getKey());
1078 if (p != null && valEquals(p.getValue(), value)) {
1079 deleteEntry(p);
1080 return true;
1081 }
1082 return false;
1083 }
1084
1085 public int size() {
1086 return TreeMap.this.size();
1087 }
1088
1089 public void clear() {
1090 TreeMap.this.clear();
1091 }
1092
1093 public Spliterator<Map.Entry<K,V>> spliterator() {
1094 return new EntrySpliterator<>(TreeMap.this, null, null, 0, -1, 0);
1095 }
1096 }
1097
1098 /*
1099 * Unlike Values and EntrySet, the KeySet class is static,
1100 * delegating to a NavigableMap to allow use by SubMaps, which
1101 * outweighs the ugliness of needing type-tests for the following
1102 * Iterator methods that are defined appropriately in main versus
1103 * submap classes.
1104 */
1105
1106 Iterator<K> keyIterator() {
1107 return new KeyIterator(getFirstEntry());
1108 }
1109
1110 Iterator<K> descendingKeyIterator() {
1111 return new DescendingKeyIterator(getLastEntry());
1112 }
1113
1114 static final class KeySet<E> extends AbstractSet<E> implements NavigableSet<E> {
1115 private final NavigableMap<E, ?> m;
1116 KeySet(NavigableMap<E,?> map) { m = map; }
1117
1118 public Iterator<E> iterator() {
1119 if (m instanceof TreeMap)
1120 return ((TreeMap<E,?>)m).keyIterator();
1121 else
1122 return ((TreeMap.NavigableSubMap<E,?>)m).keyIterator();
1123 }
1124
1125 public Iterator<E> descendingIterator() {
1126 if (m instanceof TreeMap)
1127 return ((TreeMap<E,?>)m).descendingKeyIterator();
1128 else
1129 return ((TreeMap.NavigableSubMap<E,?>)m).descendingKeyIterator();
1130 }
1131
1132 public int size() { return m.size(); }
1133 public boolean isEmpty() { return m.isEmpty(); }
1134 public boolean contains(Object o) { return m.containsKey(o); }
1135 public void clear() { m.clear(); }
1136 public E lower(E e) { return m.lowerKey(e); }
1137 public E floor(E e) { return m.floorKey(e); }
1138 public E ceiling(E e) { return m.ceilingKey(e); }
1139 public E higher(E e) { return m.higherKey(e); }
1140 public E first() { return m.firstKey(); }
1141 public E last() { return m.lastKey(); }
1142 public Comparator<? super E> comparator() { return m.comparator(); }
1143 public E pollFirst() {
1144 Map.Entry<E,?> e = m.pollFirstEntry();
1145 return (e == null) ? null : e.getKey();
1146 }
1147 public E pollLast() {
1148 Map.Entry<E,?> e = m.pollLastEntry();
1149 return (e == null) ? null : e.getKey();
1150 }
1151 public boolean remove(Object o) {
1152 int oldSize = size();
1153 m.remove(o);
1154 return size() != oldSize;
1155 }
1156 public NavigableSet<E> subSet(E fromElement, boolean fromInclusive,
1157 E toElement, boolean toInclusive) {
1158 return new KeySet<>(m.subMap(fromElement, fromInclusive,
1159 toElement, toInclusive));
1160 }
1161 public NavigableSet<E> headSet(E toElement, boolean inclusive) {
1162 return new KeySet<>(m.headMap(toElement, inclusive));
1163 }
1164 public NavigableSet<E> tailSet(E fromElement, boolean inclusive) {
1165 return new KeySet<>(m.tailMap(fromElement, inclusive));
1166 }
1167 public SortedSet<E> subSet(E fromElement, E toElement) {
1168 return subSet(fromElement, true, toElement, false);
1169 }
1170 public SortedSet<E> headSet(E toElement) {
1171 return headSet(toElement, false);
1172 }
1173 public SortedSet<E> tailSet(E fromElement) {
1174 return tailSet(fromElement, true);
1175 }
1176 public NavigableSet<E> descendingSet() {
1177 return new KeySet<>(m.descendingMap());
1178 }
1179
1180 public Spliterator<E> spliterator() {
1181 return keySpliteratorFor(m);
1182 }
1183 }
1184
1185 /**
1186 * Base class for TreeMap Iterators
1187 */
1188 abstract class PrivateEntryIterator<T> implements Iterator<T> {
1189 Entry<K,V> next;
1190 Entry<K,V> lastReturned;
1191 int expectedModCount;
1192
1193 PrivateEntryIterator(Entry<K,V> first) {
1194 expectedModCount = modCount;
1195 lastReturned = null;
1196 next = first;
1197 }
1198
1199 public final boolean hasNext() {
1200 return next != null;
1201 }
1202
1203 final Entry<K,V> nextEntry() {
1204 Entry<K,V> e = next;
1205 if (e == null)
1206 throw new NoSuchElementException();
1207 if (modCount != expectedModCount)
1208 throw new ConcurrentModificationException();
1209 next = successor(e);
1210 lastReturned = e;
1211 return e;
1212 }
1213
1214 final Entry<K,V> prevEntry() {
1215 Entry<K,V> e = next;
1216 if (e == null)
1217 throw new NoSuchElementException();
1218 if (modCount != expectedModCount)
1219 throw new ConcurrentModificationException();
1220 next = predecessor(e);
1221 lastReturned = e;
1222 return e;
1223 }
1224
1225 public void remove() {
1226 if (lastReturned == null)
1227 throw new IllegalStateException();
1228 if (modCount != expectedModCount)
1229 throw new ConcurrentModificationException();
1230 // deleted entries are replaced by their successors
1231 if (lastReturned.left != null && lastReturned.right != null)
1232 next = lastReturned;
1233 deleteEntry(lastReturned);
1234 expectedModCount = modCount;
1235 lastReturned = null;
1236 }
1237 }
1238
1239 final class EntryIterator extends PrivateEntryIterator<Map.Entry<K,V>> {
1240 EntryIterator(Entry<K,V> first) {
1241 super(first);
1242 }
1243 public Map.Entry<K,V> next() {
1244 return nextEntry();
1245 }
1246 }
1247
1248 final class ValueIterator extends PrivateEntryIterator<V> {
1249 ValueIterator(Entry<K,V> first) {
1250 super(first);
1251 }
1252 public V next() {
1253 return nextEntry().value;
1254 }
1255 }
1256
1257 final class KeyIterator extends PrivateEntryIterator<K> {
1258 KeyIterator(Entry<K,V> first) {
1259 super(first);
1260 }
1261 public K next() {
1262 return nextEntry().key;
1263 }
1264 }
1265
1266 final class DescendingKeyIterator extends PrivateEntryIterator<K> {
1267 DescendingKeyIterator(Entry<K,V> first) {
1268 super(first);
1269 }
1270 public K next() {
1271 return prevEntry().key;
1272 }
1273 public void remove() {
1274 if (lastReturned == null)
1275 throw new IllegalStateException();
1276 if (modCount != expectedModCount)
1277 throw new ConcurrentModificationException();
1278 deleteEntry(lastReturned);
1279 lastReturned = null;
1280 expectedModCount = modCount;
1281 }
1282 }
1283
1284 // Little utilities
1285
1286 /**
1287 * Compares two keys using the correct comparison method for this TreeMap.
1288 */
1289 @SuppressWarnings("unchecked")
1290 final int compare(Object k1, Object k2) {
1291 return comparator==null ? ((Comparable<? super K>)k1).compareTo((K)k2)
1292 : comparator.compare((K)k1, (K)k2);
1293 }
1294
1295 /**
1296 * Test two values for equality. Differs from o1.equals(o2) only in
1297 * that it copes with {@code null} o1 properly.
1298 */
1299 static final boolean valEquals(Object o1, Object o2) {
1300 return (o1==null ? o2==null : o1.equals(o2));
1301 }
1302
1303 /**
1304 * Return SimpleImmutableEntry for entry, or null if null
1305 */
1306 static <K,V> Map.Entry<K,V> exportEntry(TreeMap.Entry<K,V> e) {
1307 return (e == null) ? null :
1308 new AbstractMap.SimpleImmutableEntry<>(e);
1309 }
1310
1311 /**
1312 * Return key for entry, or null if null
1313 */
1314 static <K,V> K keyOrNull(TreeMap.Entry<K,V> e) {
1315 return (e == null) ? null : e.key;
1316 }
1317
1318 /**
1319 * Returns the key corresponding to the specified Entry.
1320 * @throws NoSuchElementException if the Entry is null
1321 */
1322 static <K> K key(Entry<K,?> e) {
1323 if (e==null)
1324 throw new NoSuchElementException();
1325 return e.key;
1326 }
1327
1328
1329 // SubMaps
1330
1331 /**
1332 * Dummy value serving as unmatchable fence key for unbounded
1333 * SubMapIterators
1334 */
1335 private static final Object UNBOUNDED = new Object();
1336
1337 /**
1338 * @serial include
1339 */
1340 abstract static class NavigableSubMap<K,V> extends AbstractMap<K,V>
1341 implements NavigableMap<K,V>, java.io.Serializable {
1342 private static final long serialVersionUID = -2102997345730753016L;
1343 /**
1344 * The backing map.
1345 */
1346 final TreeMap<K,V> m;
1347
1348 /**
1349 * Endpoints are represented as triples (fromStart, lo,
1350 * loInclusive) and (toEnd, hi, hiInclusive). If fromStart is
1351 * true, then the low (absolute) bound is the start of the
1352 * backing map, and the other values are ignored. Otherwise,
1353 * if loInclusive is true, lo is the inclusive bound, else lo
1354 * is the exclusive bound. Similarly for the upper bound.
1355 */
1356 final K lo, hi;
1357 final boolean fromStart, toEnd;
1358 final boolean loInclusive, hiInclusive;
1359
1360 NavigableSubMap(TreeMap<K,V> m,
1361 boolean fromStart, K lo, boolean loInclusive,
1362 boolean toEnd, K hi, boolean hiInclusive) {
1363 if (!fromStart && !toEnd) {
1364 if (m.compare(lo, hi) > 0)
1365 throw new IllegalArgumentException("fromKey > toKey");
1366 } else {
1367 if (!fromStart) // type check
1368 m.compare(lo, lo);
1369 if (!toEnd)
1370 m.compare(hi, hi);
1371 }
1372
1373 this.m = m;
1374 this.fromStart = fromStart;
1375 this.lo = lo;
1376 this.loInclusive = loInclusive;
1377 this.toEnd = toEnd;
1378 this.hi = hi;
1379 this.hiInclusive = hiInclusive;
1380 }
1381
1382 // internal utilities
1383
1384 final boolean tooLow(Object key) {
1385 if (!fromStart) {
1386 int c = m.compare(key, lo);
1387 if (c < 0 || (c == 0 && !loInclusive))
1388 return true;
1389 }
1390 return false;
1391 }
1392
1393 final boolean tooHigh(Object key) {
1394 if (!toEnd) {
1395 int c = m.compare(key, hi);
1396 if (c > 0 || (c == 0 && !hiInclusive))
1397 return true;
1398 }
1399 return false;
1400 }
1401
1402 final boolean inRange(Object key) {
1403 return !tooLow(key) && !tooHigh(key);
1404 }
1405
1406 final boolean inClosedRange(Object key) {
1407 return (fromStart || m.compare(key, lo) >= 0)
1408 && (toEnd || m.compare(hi, key) >= 0);
1409 }
1410
1411 final boolean inRange(Object key, boolean inclusive) {
1412 return inclusive ? inRange(key) : inClosedRange(key);
1413 }
1414
1415 /*
1416 * Absolute versions of relation operations.
1417 * Subclasses map to these using like-named "sub"
1418 * versions that invert senses for descending maps
1419 */
1420
1421 final TreeMap.Entry<K,V> absLowest() {
1422 TreeMap.Entry<K,V> e =
1423 (fromStart ? m.getFirstEntry() :
1424 (loInclusive ? m.getCeilingEntry(lo) :
1425 m.getHigherEntry(lo)));
1426 return (e == null || tooHigh(e.key)) ? null : e;
1427 }
1428
1429 final TreeMap.Entry<K,V> absHighest() {
1430 TreeMap.Entry<K,V> e =
1431 (toEnd ? m.getLastEntry() :
1432 (hiInclusive ? m.getFloorEntry(hi) :
1433 m.getLowerEntry(hi)));
1434 return (e == null || tooLow(e.key)) ? null : e;
1435 }
1436
1437 final TreeMap.Entry<K,V> absCeiling(K key) {
1438 if (tooLow(key))
1439 return absLowest();
1440 TreeMap.Entry<K,V> e = m.getCeilingEntry(key);
1441 return (e == null || tooHigh(e.key)) ? null : e;
1442 }
1443
1444 final TreeMap.Entry<K,V> absHigher(K key) {
1445 if (tooLow(key))
1446 return absLowest();
1447 TreeMap.Entry<K,V> e = m.getHigherEntry(key);
1448 return (e == null || tooHigh(e.key)) ? null : e;
1449 }
1450
1451 final TreeMap.Entry<K,V> absFloor(K key) {
1452 if (tooHigh(key))
1453 return absHighest();
1454 TreeMap.Entry<K,V> e = m.getFloorEntry(key);
1455 return (e == null || tooLow(e.key)) ? null : e;
1456 }
1457
1458 final TreeMap.Entry<K,V> absLower(K key) {
1459 if (tooHigh(key))
1460 return absHighest();
1461 TreeMap.Entry<K,V> e = m.getLowerEntry(key);
1462 return (e == null || tooLow(e.key)) ? null : e;
1463 }
1464
1465 /** Returns the absolute high fence for ascending traversal */
1466 final TreeMap.Entry<K,V> absHighFence() {
1467 return (toEnd ? null : (hiInclusive ?
1468 m.getHigherEntry(hi) :
1469 m.getCeilingEntry(hi)));
1470 }
1471
1472 /** Return the absolute low fence for descending traversal */
1473 final TreeMap.Entry<K,V> absLowFence() {
1474 return (fromStart ? null : (loInclusive ?
1475 m.getLowerEntry(lo) :
1476 m.getFloorEntry(lo)));
1477 }
1478
1479 // Abstract methods defined in ascending vs descending classes
1480 // These relay to the appropriate absolute versions
1481
1482 abstract TreeMap.Entry<K,V> subLowest();
1483 abstract TreeMap.Entry<K,V> subHighest();
1484 abstract TreeMap.Entry<K,V> subCeiling(K key);
1485 abstract TreeMap.Entry<K,V> subHigher(K key);
1486 abstract TreeMap.Entry<K,V> subFloor(K key);
1487 abstract TreeMap.Entry<K,V> subLower(K key);
1488
1489 /** Returns ascending iterator from the perspective of this submap */
1490 abstract Iterator<K> keyIterator();
1491
1492 abstract Spliterator<K> keySpliterator();
1493
1494 /** Returns descending iterator from the perspective of this submap */
1495 abstract Iterator<K> descendingKeyIterator();
1496
1497 // public methods
1498
1499 public boolean isEmpty() {
1500 return (fromStart && toEnd) ? m.isEmpty() : entrySet().isEmpty();
1501 }
1502
1503 public int size() {
1504 return (fromStart && toEnd) ? m.size() : entrySet().size();
1505 }
1506
1507 public final boolean containsKey(Object key) {
1508 return inRange(key) && m.containsKey(key);
1509 }
1510
1511 public final V put(K key, V value) {
1512 if (!inRange(key))
1513 throw new IllegalArgumentException("key out of range");
1514 return m.put(key, value);
1515 }
1516
1517 public final V get(Object key) {
1518 return !inRange(key) ? null : m.get(key);
1519 }
1520
1521 public final V remove(Object key) {
1522 return !inRange(key) ? null : m.remove(key);
1523 }
1524
1525 public final Map.Entry<K,V> ceilingEntry(K key) {
1526 return exportEntry(subCeiling(key));
1527 }
1528
1529 public final K ceilingKey(K key) {
1530 return keyOrNull(subCeiling(key));
1531 }
1532
1533 public final Map.Entry<K,V> higherEntry(K key) {
1534 return exportEntry(subHigher(key));
1535 }
1536
1537 public final K higherKey(K key) {
1538 return keyOrNull(subHigher(key));
1539 }
1540
1541 public final Map.Entry<K,V> floorEntry(K key) {
1542 return exportEntry(subFloor(key));
1543 }
1544
1545 public final K floorKey(K key) {
1546 return keyOrNull(subFloor(key));
1547 }
1548
1549 public final Map.Entry<K,V> lowerEntry(K key) {
1550 return exportEntry(subLower(key));
1551 }
1552
1553 public final K lowerKey(K key) {
1554 return keyOrNull(subLower(key));
1555 }
1556
1557 public final K firstKey() {
1558 return key(subLowest());
1559 }
1560
1561 public final K lastKey() {
1562 return key(subHighest());
1563 }
1564
1565 public final Map.Entry<K,V> firstEntry() {
1566 return exportEntry(subLowest());
1567 }
1568
1569 public final Map.Entry<K,V> lastEntry() {
1570 return exportEntry(subHighest());
1571 }
1572
1573 public final Map.Entry<K,V> pollFirstEntry() {
1574 TreeMap.Entry<K,V> e = subLowest();
1575 Map.Entry<K,V> result = exportEntry(e);
1576 if (e != null)
1577 m.deleteEntry(e);
1578 return result;
1579 }
1580
1581 public final Map.Entry<K,V> pollLastEntry() {
1582 TreeMap.Entry<K,V> e = subHighest();
1583 Map.Entry<K,V> result = exportEntry(e);
1584 if (e != null)
1585 m.deleteEntry(e);
1586 return result;
1587 }
1588
1589 // Views
1590 transient NavigableMap<K,V> descendingMapView;
1591 transient EntrySetView entrySetView;
1592 transient KeySet<K> navigableKeySetView;
1593
1594 public final NavigableSet<K> navigableKeySet() {
1595 KeySet<K> nksv = navigableKeySetView;
1596 return (nksv != null) ? nksv :
1597 (navigableKeySetView = new TreeMap.KeySet<>(this));
1598 }
1599
1600 public final Set<K> keySet() {
1601 return navigableKeySet();
1602 }
1603
1604 public NavigableSet<K> descendingKeySet() {
1605 return descendingMap().navigableKeySet();
1606 }
1607
1608 public final SortedMap<K,V> subMap(K fromKey, K toKey) {
1609 return subMap(fromKey, true, toKey, false);
1610 }
1611
1612 public final SortedMap<K,V> headMap(K toKey) {
1613 return headMap(toKey, false);
1614 }
1615
1616 public final SortedMap<K,V> tailMap(K fromKey) {
1617 return tailMap(fromKey, true);
1618 }
1619
1620 // View classes
1621
1622 abstract class EntrySetView extends AbstractSet<Map.Entry<K,V>> {
1623 private transient int size = -1, sizeModCount;
1624
1625 public int size() {
1626 if (fromStart && toEnd)
1627 return m.size();
1628 if (size == -1 || sizeModCount != m.modCount) {
1629 sizeModCount = m.modCount;
1630 size = 0;
1631 Iterator<?> i = iterator();
1632 while (i.hasNext()) {
1633 size++;
1634 i.next();
1635 }
1636 }
1637 return size;
1638 }
1639
1640 public boolean isEmpty() {
1641 TreeMap.Entry<K,V> n = absLowest();
1642 return n == null || tooHigh(n.key);
1643 }
1644
1645 public boolean contains(Object o) {
1646 if (!(o instanceof Map.Entry))
1647 return false;
1648 Map.Entry<?,?> entry = (Map.Entry<?,?>) o;
1649 Object key = entry.getKey();
1650 if (!inRange(key))
1651 return false;
1652 TreeMap.Entry<?,?> node = m.getEntry(key);
1653 return node != null &&
1654 valEquals(node.getValue(), entry.getValue());
1655 }
1656
1657 public boolean remove(Object o) {
1658 if (!(o instanceof Map.Entry))
1659 return false;
1660 Map.Entry<?,?> entry = (Map.Entry<?,?>) o;
1661 Object key = entry.getKey();
1662 if (!inRange(key))
1663 return false;
1664 TreeMap.Entry<K,V> node = m.getEntry(key);
1665 if (node!=null && valEquals(node.getValue(),
1666 entry.getValue())) {
1667 m.deleteEntry(node);
1668 return true;
1669 }
1670 return false;
1671 }
1672 }
1673
1674 /**
1675 * Iterators for SubMaps
1676 */
1677 abstract class SubMapIterator<T> implements Iterator<T> {
1678 TreeMap.Entry<K,V> lastReturned;
1679 TreeMap.Entry<K,V> next;
1680 final Object fenceKey;
1681 int expectedModCount;
1682
1683 SubMapIterator(TreeMap.Entry<K,V> first,
1684 TreeMap.Entry<K,V> fence) {
1685 expectedModCount = m.modCount;
1686 lastReturned = null;
1687 next = first;
1688 fenceKey = fence == null ? UNBOUNDED : fence.key;
1689 }
1690
1691 public final boolean hasNext() {
1692 return next != null && next.key != fenceKey;
1693 }
1694
1695 final TreeMap.Entry<K,V> nextEntry() {
1696 TreeMap.Entry<K,V> e = next;
1697 if (e == null || e.key == fenceKey)
1698 throw new NoSuchElementException();
1699 if (m.modCount != expectedModCount)
1700 throw new ConcurrentModificationException();
1701 next = successor(e);
1702 lastReturned = e;
1703 return e;
1704 }
1705
1706 final TreeMap.Entry<K,V> prevEntry() {
1707 TreeMap.Entry<K,V> e = next;
1708 if (e == null || e.key == fenceKey)
1709 throw new NoSuchElementException();
1710 if (m.modCount != expectedModCount)
1711 throw new ConcurrentModificationException();
1712 next = predecessor(e);
1713 lastReturned = e;
1714 return e;
1715 }
1716
1717 final void removeAscending() {
1718 if (lastReturned == null)
1719 throw new IllegalStateException();
1720 if (m.modCount != expectedModCount)
1721 throw new ConcurrentModificationException();
1722 // deleted entries are replaced by their successors
1723 if (lastReturned.left != null && lastReturned.right != null)
1724 next = lastReturned;
1725 m.deleteEntry(lastReturned);
1726 lastReturned = null;
1727 expectedModCount = m.modCount;
1728 }
1729
1730 final void removeDescending() {
1731 if (lastReturned == null)
1732 throw new IllegalStateException();
1733 if (m.modCount != expectedModCount)
1734 throw new ConcurrentModificationException();
1735 m.deleteEntry(lastReturned);
1736 lastReturned = null;
1737 expectedModCount = m.modCount;
1738 }
1739
1740 }
1741
1742 final class SubMapEntryIterator extends SubMapIterator<Map.Entry<K,V>> {
1743 SubMapEntryIterator(TreeMap.Entry<K,V> first,
1744 TreeMap.Entry<K,V> fence) {
1745 super(first, fence);
1746 }
1747 public Map.Entry<K,V> next() {
1748 return nextEntry();
1749 }
1750 public void remove() {
1751 removeAscending();
1752 }
1753 }
1754
1755 final class DescendingSubMapEntryIterator extends SubMapIterator<Map.Entry<K,V>> {
1756 DescendingSubMapEntryIterator(TreeMap.Entry<K,V> last,
1757 TreeMap.Entry<K,V> fence) {
1758 super(last, fence);
1759 }
1760
1761 public Map.Entry<K,V> next() {
1762 return prevEntry();
1763 }
1764 public void remove() {
1765 removeDescending();
1766 }
1767 }
1768
1769 // Implement minimal Spliterator as KeySpliterator backup
1770 final class SubMapKeyIterator extends SubMapIterator<K>
1771 implements Spliterator<K> {
1772 SubMapKeyIterator(TreeMap.Entry<K,V> first,
1773 TreeMap.Entry<K,V> fence) {
1774 super(first, fence);
1775 }
1776 public K next() {
1777 return nextEntry().key;
1778 }
1779 public void remove() {
1780 removeAscending();
1781 }
1782 public Spliterator<K> trySplit() {
1783 return null;
1784 }
1785 public void forEachRemaining(Consumer<? super K> action) {
1786 while (hasNext())
1787 action.accept(next());
1788 }
1789 public boolean tryAdvance(Consumer<? super K> action) {
1790 if (hasNext()) {
1791 action.accept(next());
1792 return true;
1793 }
1794 return false;
1795 }
1796 public long estimateSize() {
1797 return Long.MAX_VALUE;
1798 }
1799 public int characteristics() {
1800 return Spliterator.DISTINCT | Spliterator.ORDERED |
1801 Spliterator.SORTED;
1802 }
1803 public final Comparator<? super K> getComparator() {
1804 return NavigableSubMap.this.comparator();
1805 }
1806 }
1807
1808 final class DescendingSubMapKeyIterator extends SubMapIterator<K>
1809 implements Spliterator<K> {
1810 DescendingSubMapKeyIterator(TreeMap.Entry<K,V> last,
1811 TreeMap.Entry<K,V> fence) {
1812 super(last, fence);
1813 }
1814 public K next() {
1815 return prevEntry().key;
1816 }
1817 public void remove() {
1818 removeDescending();
1819 }
1820 public Spliterator<K> trySplit() {
1821 return null;
1822 }
1823 public void forEachRemaining(Consumer<? super K> action) {
1824 while (hasNext())
1825 action.accept(next());
1826 }
1827 public boolean tryAdvance(Consumer<? super K> action) {
1828 if (hasNext()) {
1829 action.accept(next());
1830 return true;
1831 }
1832 return false;
1833 }
1834 public long estimateSize() {
1835 return Long.MAX_VALUE;
1836 }
1837 public int characteristics() {
1838 return Spliterator.DISTINCT | Spliterator.ORDERED;
1839 }
1840 }
1841 }
1842
1843 /**
1844 * @serial include
1845 */
1846 static final class AscendingSubMap<K,V> extends NavigableSubMap<K,V> {
1847 private static final long serialVersionUID = 912986545866124060L;
1848
1849 AscendingSubMap(TreeMap<K,V> m,
1850 boolean fromStart, K lo, boolean loInclusive,
1851 boolean toEnd, K hi, boolean hiInclusive) {
1852 super(m, fromStart, lo, loInclusive, toEnd, hi, hiInclusive);
1853 }
1854
1855 public Comparator<? super K> comparator() {
1856 return m.comparator();
1857 }
1858
1859 public NavigableMap<K,V> subMap(K fromKey, boolean fromInclusive,
1860 K toKey, boolean toInclusive) {
1861 if (!inRange(fromKey, fromInclusive))
1862 throw new IllegalArgumentException("fromKey out of range");
1863 if (!inRange(toKey, toInclusive))
1864 throw new IllegalArgumentException("toKey out of range");
1865 return new AscendingSubMap<>(m,
1866 false, fromKey, fromInclusive,
1867 false, toKey, toInclusive);
1868 }
1869
1870 public NavigableMap<K,V> headMap(K toKey, boolean inclusive) {
1871 if (!inRange(toKey, inclusive))
1872 throw new IllegalArgumentException("toKey out of range");
1873 return new AscendingSubMap<>(m,
1874 fromStart, lo, loInclusive,
1875 false, toKey, inclusive);
1876 }
1877
1878 public NavigableMap<K,V> tailMap(K fromKey, boolean inclusive) {
1879 if (!inRange(fromKey, inclusive))
1880 throw new IllegalArgumentException("fromKey out of range");
1881 return new AscendingSubMap<>(m,
1882 false, fromKey, inclusive,
1883 toEnd, hi, hiInclusive);
1884 }
1885
1886 public NavigableMap<K,V> descendingMap() {
1887 NavigableMap<K,V> mv = descendingMapView;
1888 return (mv != null) ? mv :
1889 (descendingMapView =
1890 new DescendingSubMap<>(m,
1891 fromStart, lo, loInclusive,
1892 toEnd, hi, hiInclusive));
1893 }
1894
1895 Iterator<K> keyIterator() {
1896 return new SubMapKeyIterator(absLowest(), absHighFence());
1897 }
1898
1899 Spliterator<K> keySpliterator() {
1900 return new SubMapKeyIterator(absLowest(), absHighFence());
1901 }
1902
1903 Iterator<K> descendingKeyIterator() {
1904 return new DescendingSubMapKeyIterator(absHighest(), absLowFence());
1905 }
1906
1907 final class AscendingEntrySetView extends EntrySetView {
1908 public Iterator<Map.Entry<K,V>> iterator() {
1909 return new SubMapEntryIterator(absLowest(), absHighFence());
1910 }
1911 }
1912
1913 public Set<Map.Entry<K,V>> entrySet() {
1914 EntrySetView es = entrySetView;
1915 return (es != null) ? es : (entrySetView = new AscendingEntrySetView());
1916 }
1917
1918 TreeMap.Entry<K,V> subLowest() { return absLowest(); }
1919 TreeMap.Entry<K,V> subHighest() { return absHighest(); }
1920 TreeMap.Entry<K,V> subCeiling(K key) { return absCeiling(key); }
1921 TreeMap.Entry<K,V> subHigher(K key) { return absHigher(key); }
1922 TreeMap.Entry<K,V> subFloor(K key) { return absFloor(key); }
1923 TreeMap.Entry<K,V> subLower(K key) { return absLower(key); }
1924 }
1925
1926 /**
1927 * @serial include
1928 */
1929 static final class DescendingSubMap<K,V> extends NavigableSubMap<K,V> {
1930 private static final long serialVersionUID = 912986545866120460L;
1931 DescendingSubMap(TreeMap<K,V> m,
1932 boolean fromStart, K lo, boolean loInclusive,
1933 boolean toEnd, K hi, boolean hiInclusive) {
1934 super(m, fromStart, lo, loInclusive, toEnd, hi, hiInclusive);
1935 }
1936
1937 private final Comparator<? super K> reverseComparator =
1938 Collections.reverseOrder(m.comparator);
1939
1940 public Comparator<? super K> comparator() {
1941 return reverseComparator;
1942 }
1943
1944 public NavigableMap<K,V> subMap(K fromKey, boolean fromInclusive,
1945 K toKey, boolean toInclusive) {
1946 if (!inRange(fromKey, fromInclusive))
1947 throw new IllegalArgumentException("fromKey out of range");
1948 if (!inRange(toKey, toInclusive))
1949 throw new IllegalArgumentException("toKey out of range");
1950 return new DescendingSubMap<>(m,
1951 false, toKey, toInclusive,
1952 false, fromKey, fromInclusive);
1953 }
1954
1955 public NavigableMap<K,V> headMap(K toKey, boolean inclusive) {
1956 if (!inRange(toKey, inclusive))
1957 throw new IllegalArgumentException("toKey out of range");
1958 return new DescendingSubMap<>(m,
1959 false, toKey, inclusive,
1960 toEnd, hi, hiInclusive);
1961 }
1962
1963 public NavigableMap<K,V> tailMap(K fromKey, boolean inclusive) {
1964 if (!inRange(fromKey, inclusive))
1965 throw new IllegalArgumentException("fromKey out of range");
1966 return new DescendingSubMap<>(m,
1967 fromStart, lo, loInclusive,
1968 false, fromKey, inclusive);
1969 }
1970
1971 public NavigableMap<K,V> descendingMap() {
1972 NavigableMap<K,V> mv = descendingMapView;
1973 return (mv != null) ? mv :
1974 (descendingMapView =
1975 new AscendingSubMap<>(m,
1976 fromStart, lo, loInclusive,
1977 toEnd, hi, hiInclusive));
1978 }
1979
1980 Iterator<K> keyIterator() {
1981 return new DescendingSubMapKeyIterator(absHighest(), absLowFence());
1982 }
1983
1984 Spliterator<K> keySpliterator() {
1985 return new DescendingSubMapKeyIterator(absHighest(), absLowFence());
1986 }
1987
1988 Iterator<K> descendingKeyIterator() {
1989 return new SubMapKeyIterator(absLowest(), absHighFence());
1990 }
1991
1992 final class DescendingEntrySetView extends EntrySetView {
1993 public Iterator<Map.Entry<K,V>> iterator() {
1994 return new DescendingSubMapEntryIterator(absHighest(), absLowFence());
1995 }
1996 }
1997
1998 public Set<Map.Entry<K,V>> entrySet() {
1999 EntrySetView es = entrySetView;
2000 return (es != null) ? es : (entrySetView = new DescendingEntrySetView());
2001 }
2002
2003 TreeMap.Entry<K,V> subLowest() { return absHighest(); }
2004 TreeMap.Entry<K,V> subHighest() { return absLowest(); }
2005 TreeMap.Entry<K,V> subCeiling(K key) { return absFloor(key); }
2006 TreeMap.Entry<K,V> subHigher(K key) { return absLower(key); }
2007 TreeMap.Entry<K,V> subFloor(K key) { return absCeiling(key); }
2008 TreeMap.Entry<K,V> subLower(K key) { return absHigher(key); }
2009 }
2010
2011 /**
2012 * This class exists solely for the sake of serialization
2013 * compatibility with previous releases of TreeMap that did not
2014 * support NavigableMap. It translates an old-version SubMap into
2015 * a new-version AscendingSubMap. This class is never otherwise
2016 * used.
2017 *
2018 * @serial include
2019 */
2020 private class SubMap extends AbstractMap<K,V>
2021 implements SortedMap<K,V>, java.io.Serializable {
2022 private static final long serialVersionUID = -6520786458950516097L;
2023 private boolean fromStart = false, toEnd = false;
2024 private K fromKey, toKey;
2025 private Object readResolve() {
2026 return new AscendingSubMap<>(TreeMap.this,
2027 fromStart, fromKey, true,
2028 toEnd, toKey, false);
2029 }
2030 public Set<Map.Entry<K,V>> entrySet() { throw new InternalError(); }
2031 public K lastKey() { throw new InternalError(); }
2032 public K firstKey() { throw new InternalError(); }
2033 public SortedMap<K,V> subMap(K fromKey, K toKey) { throw new InternalError(); }
2034 public SortedMap<K,V> headMap(K toKey) { throw new InternalError(); }
2035 public SortedMap<K,V> tailMap(K fromKey) { throw new InternalError(); }
2036 public Comparator<? super K> comparator() { throw new InternalError(); }
2037 }
2038
2039
2040 // Red-black mechanics
2041
2042 private static final boolean RED = false;
2043 private static final boolean BLACK = true;
2044
2045 /**
2046 * Node in the Tree. Doubles as a means to pass key-value pairs back to
2047 * user (see Map.Entry).
2048 */
2049
2050 static final class Entry<K,V> implements Map.Entry<K,V> {
2051 K key;
2052 V value;
2053 Entry<K,V> left;
2054 Entry<K,V> right;
2055 Entry<K,V> parent;
2056 boolean color = BLACK;
2057
2058 /**
2059 * Make a new cell with given key, value, and parent, and with
2060 * {@code null} child links, and BLACK color.
2061 */
2062 Entry(K key, V value, Entry<K,V> parent) {
2063 this.key = key;
2064 this.value = value;
2065 this.parent = parent;
2066 }
2067
2068 /**
2069 * Returns the key.
2070 *
2071 * @return the key
2072 */
2073 public K getKey() {
2074 return key;
2075 }
2076
2077 /**
2078 * Returns the value associated with the key.
2079 *
2080 * @return the value associated with the key
2081 */
2082 public V getValue() {
2083 return value;
2084 }
2085
2086 /**
2087 * Replaces the value currently associated with the key with the given
2088 * value.
2089 *
2090 * @return the value associated with the key before this method was
2091 * called
2092 */
2093 public V setValue(V value) {
2094 V oldValue = this.value;
2095 this.value = value;
2096 return oldValue;
2097 }
2098
2099 public boolean equals(Object o) {
2100 if (!(o instanceof Map.Entry))
2101 return false;
2102 Map.Entry<?,?> e = (Map.Entry<?,?>)o;
2103
2104 return valEquals(key,e.getKey()) && valEquals(value,e.getValue());
2105 }
2106
2107 public int hashCode() {
2108 int keyHash = (key==null ? 0 : key.hashCode());
2109 int valueHash = (value==null ? 0 : value.hashCode());
2110 return keyHash ^ valueHash;
2111 }
2112
2113 public String toString() {
2114 return key + "=" + value;
2115 }
2116 }
2117
2118 /**
2119 * Returns the first Entry in the TreeMap (according to the TreeMap's
2120 * key-sort function). Returns null if the TreeMap is empty.
2121 */
2122 final Entry<K,V> getFirstEntry() {
2123 Entry<K,V> p = root;
2124 if (p != null)
2125 while (p.left != null)
2126 p = p.left;
2127 return p;
2128 }
2129
2130 /**
2131 * Returns the last Entry in the TreeMap (according to the TreeMap's
2132 * key-sort function). Returns null if the TreeMap is empty.
2133 */
2134 final Entry<K,V> getLastEntry() {
2135 Entry<K,V> p = root;
2136 if (p != null)
2137 while (p.right != null)
2138 p = p.right;
2139 return p;
2140 }
2141
2142 /**
2143 * Returns the successor of the specified Entry, or null if no such.
2144 */
2145 static <K,V> TreeMap.Entry<K,V> successor(Entry<K,V> t) {
2146 if (t == null)
2147 return null;
2148 else if (t.right != null) {
2149 Entry<K,V> p = t.right;
2150 while (p.left != null)
2151 p = p.left;
2152 return p;
2153 } else {
2154 Entry<K,V> p = t.parent;
2155 Entry<K,V> ch = t;
2156 while (p != null && ch == p.right) {
2157 ch = p;
2158 p = p.parent;
2159 }
2160 return p;
2161 }
2162 }
2163
2164 /**
2165 * Returns the predecessor of the specified Entry, or null if no such.
2166 */
2167 static <K,V> Entry<K,V> predecessor(Entry<K,V> t) {
2168 if (t == null)
2169 return null;
2170 else if (t.left != null) {
2171 Entry<K,V> p = t.left;
2172 while (p.right != null)
2173 p = p.right;
2174 return p;
2175 } else {
2176 Entry<K,V> p = t.parent;
2177 Entry<K,V> ch = t;
2178 while (p != null && ch == p.left) {
2179 ch = p;
2180 p = p.parent;
2181 }
2182 return p;
2183 }
2184 }
2185
2186 /**
2187 * Balancing operations.
2188 *
2189 * Implementations of rebalancings during insertion and deletion are
2190 * slightly different than the CLR version. Rather than using dummy
2191 * nilnodes, we use a set of accessors that deal properly with null. They
2192 * are used to avoid messiness surrounding nullness checks in the main
2193 * algorithms.
2194 */
2195
2196 private static <K,V> boolean colorOf(Entry<K,V> p) {
2197 return (p == null ? BLACK : p.color);
2198 }
2199
2200 private static <K,V> Entry<K,V> parentOf(Entry<K,V> p) {
2201 return (p == null ? null: p.parent);
2202 }
2203
2204 private static <K,V> void setColor(Entry<K,V> p, boolean c) {
2205 if (p != null)
2206 p.color = c;
2207 }
2208
2209 private static <K,V> Entry<K,V> leftOf(Entry<K,V> p) {
2210 return (p == null) ? null: p.left;
2211 }
2212
2213 private static <K,V> Entry<K,V> rightOf(Entry<K,V> p) {
2214 return (p == null) ? null: p.right;
2215 }
2216
2217 /** From CLR */
2218 private void rotateLeft(Entry<K,V> p) {
2219 if (p != null) {
2220 Entry<K,V> r = p.right;
2221 p.right = r.left;
2222 if (r.left != null)
2223 r.left.parent = p;
2224 r.parent = p.parent;
2225 if (p.parent == null)
2226 root = r;
2227 else if (p.parent.left == p)
2228 p.parent.left = r;
2229 else
2230 p.parent.right = r;
2231 r.left = p;
2232 p.parent = r;
2233 }
2234 }
2235
2236 /** From CLR */
2237 private void rotateRight(Entry<K,V> p) {
2238 if (p != null) {
2239 Entry<K,V> l = p.left;
2240 p.left = l.right;
2241 if (l.right != null) l.right.parent = p;
2242 l.parent = p.parent;
2243 if (p.parent == null)
2244 root = l;
2245 else if (p.parent.right == p)
2246 p.parent.right = l;
2247 else p.parent.left = l;
2248 l.right = p;
2249 p.parent = l;
2250 }
2251 }
2252
2253 /** From CLR */
2254 private void fixAfterInsertion(Entry<K,V> x) {
2255 x.color = RED;
2256
2257 while (x != null && x != root && x.parent.color == RED) {
2258 if (parentOf(x) == leftOf(parentOf(parentOf(x)))) {
2259 Entry<K,V> y = rightOf(parentOf(parentOf(x)));
2260 if (colorOf(y) == RED) {
2261 setColor(parentOf(x), BLACK);
2262 setColor(y, BLACK);
2263 setColor(parentOf(parentOf(x)), RED);
2264 x = parentOf(parentOf(x));
2265 } else {
2266 if (x == rightOf(parentOf(x))) {
2267 x = parentOf(x);
2268 rotateLeft(x);
2269 }
2270 setColor(parentOf(x), BLACK);
2271 setColor(parentOf(parentOf(x)), RED);
2272 rotateRight(parentOf(parentOf(x)));
2273 }
2274 } else {
2275 Entry<K,V> y = leftOf(parentOf(parentOf(x)));
2276 if (colorOf(y) == RED) {
2277 setColor(parentOf(x), BLACK);
2278 setColor(y, BLACK);
2279 setColor(parentOf(parentOf(x)), RED);
2280 x = parentOf(parentOf(x));
2281 } else {
2282 if (x == leftOf(parentOf(x))) {
2283 x = parentOf(x);
2284 rotateRight(x);
2285 }
2286 setColor(parentOf(x), BLACK);
2287 setColor(parentOf(parentOf(x)), RED);
2288 rotateLeft(parentOf(parentOf(x)));
2289 }
2290 }
2291 }
2292 root.color = BLACK;
2293 }
2294
2295 /**
2296 * Delete node p, and then rebalance the tree.
2297 */
2298 private void deleteEntry(Entry<K,V> p) {
2299 modCount++;
2300 size--;
2301
2302 // If strictly internal, copy successor's element to p and then make p
2303 // point to successor.
2304 if (p.left != null && p.right != null) {
2305 Entry<K,V> s = successor(p);
2306 p.key = s.key;
2307 p.value = s.value;
2308 p = s;
2309 } // p has 2 children
2310
2311 // Start fixup at replacement node, if it exists.
2312 Entry<K,V> replacement = (p.left != null ? p.left : p.right);
2313
2314 if (replacement != null) {
2315 // Link replacement to parent
2316 replacement.parent = p.parent;
2317 if (p.parent == null)
2318 root = replacement;
2319 else if (p == p.parent.left)
2320 p.parent.left = replacement;
2321 else
2322 p.parent.right = replacement;
2323
2324 // Null out links so they are OK to use by fixAfterDeletion.
2325 p.left = p.right = p.parent = null;
2326
2327 // Fix replacement
2328 if (p.color == BLACK)
2329 fixAfterDeletion(replacement);
2330 } else if (p.parent == null) { // return if we are the only node.
2331 root = null;
2332 } else { // No children. Use self as phantom replacement and unlink.
2333 if (p.color == BLACK)
2334 fixAfterDeletion(p);
2335
2336 if (p.parent != null) {
2337 if (p == p.parent.left)
2338 p.parent.left = null;
2339 else if (p == p.parent.right)
2340 p.parent.right = null;
2341 p.parent = null;
2342 }
2343 }
2344 }
2345
2346 /** From CLR */
2347 private void fixAfterDeletion(Entry<K,V> x) {
2348 while (x != root && colorOf(x) == BLACK) {
2349 if (x == leftOf(parentOf(x))) {
2350 Entry<K,V> sib = rightOf(parentOf(x));
2351
2352 if (colorOf(sib) == RED) {
2353 setColor(sib, BLACK);
2354 setColor(parentOf(x), RED);
2355 rotateLeft(parentOf(x));
2356 sib = rightOf(parentOf(x));
2357 }
2358
2359 if (colorOf(leftOf(sib)) == BLACK &&
2360 colorOf(rightOf(sib)) == BLACK) {
2361 setColor(sib, RED);
2362 x = parentOf(x);
2363 } else {
2364 if (colorOf(rightOf(sib)) == BLACK) {
2365 setColor(leftOf(sib), BLACK);
2366 setColor(sib, RED);
2367 rotateRight(sib);
2368 sib = rightOf(parentOf(x));
2369 }
2370 setColor(sib, colorOf(parentOf(x)));
2371 setColor(parentOf(x), BLACK);
2372 setColor(rightOf(sib), BLACK);
2373 rotateLeft(parentOf(x));
2374 x = root;
2375 }
2376 } else { // symmetric
2377 Entry<K,V> sib = leftOf(parentOf(x));
2378
2379 if (colorOf(sib) == RED) {
2380 setColor(sib, BLACK);
2381 setColor(parentOf(x), RED);
2382 rotateRight(parentOf(x));
2383 sib = leftOf(parentOf(x));
2384 }
2385
2386 if (colorOf(rightOf(sib)) == BLACK &&
2387 colorOf(leftOf(sib)) == BLACK) {
2388 setColor(sib, RED);
2389 x = parentOf(x);
2390 } else {
2391 if (colorOf(leftOf(sib)) == BLACK) {
2392 setColor(rightOf(sib), BLACK);
2393 setColor(sib, RED);
2394 rotateLeft(sib);
2395 sib = leftOf(parentOf(x));
2396 }
2397 setColor(sib, colorOf(parentOf(x)));
2398 setColor(parentOf(x), BLACK);
2399 setColor(leftOf(sib), BLACK);
2400 rotateRight(parentOf(x));
2401 x = root;
2402 }
2403 }
2404 }
2405
2406 setColor(x, BLACK);
2407 }
2408
2409 private static final long serialVersionUID = 919286545866124006L;
2410
2411 /**
2412 * Save the state of the {@code TreeMap} instance to a stream (i.e.,
2413 * serialize it).
2414 *
2415 * @serialData The <em>size</em> of the TreeMap (the number of key-value
2416 * mappings) is emitted (int), followed by the key (Object)
2417 * and value (Object) for each key-value mapping represented
2418 * by the TreeMap. The key-value mappings are emitted in
2419 * key-order (as determined by the TreeMap's Comparator,
2420 * or by the keys' natural ordering if the TreeMap has no
2421 * Comparator).
2422 */
2423 private void writeObject(java.io.ObjectOutputStream s)
2424 throws java.io.IOException {
2425 // Write out the Comparator and any hidden stuff
2426 s.defaultWriteObject();
2427
2428 // Write out size (number of Mappings)
2429 s.writeInt(size);
2430
2431 // Write out keys and values (alternating)
2432 for (Map.Entry<K, V> e : entrySet()) {
2433 s.writeObject(e.getKey());
2434 s.writeObject(e.getValue());
2435 }
2436 }
2437
2438 /**
2439 * Reconstitute the {@code TreeMap} instance from a stream (i.e.,
2440 * deserialize it).
2441 */
2442 private void readObject(final java.io.ObjectInputStream s)
2443 throws java.io.IOException, ClassNotFoundException {
2444 // Read in the Comparator and any hidden stuff
2445 s.defaultReadObject();
2446
2447 // Read in size
2448 int size = s.readInt();
2449
2450 buildFromSorted(size, null, s, null);
2451 }
2452
2453 /** Intended to be called only from TreeSet.readObject */
2454 void readTreeSet(int size, java.io.ObjectInputStream s, V defaultVal)
2455 throws java.io.IOException, ClassNotFoundException {
2456 buildFromSorted(size, null, s, defaultVal);
2457 }
2458
2459 /** Intended to be called only from TreeSet.addAll */
2460 void addAllForTreeSet(SortedSet<? extends K> set, V defaultVal) {
2461 try {
2462 buildFromSorted(set.size(), set.iterator(), null, defaultVal);
2463 } catch (java.io.IOException | ClassNotFoundException cannotHappen) {
2464 }
2465 }
2466
2467
2468 /**
2469 * Linear time tree building algorithm from sorted data. Can accept keys
2470 * and/or values from iterator or stream. This leads to too many
2471 * parameters, but seems better than alternatives. The four formats
2472 * that this method accepts are:
2473 *
2474 * 1) An iterator of Map.Entries. (it != null, defaultVal == null).
2475 * 2) An iterator of keys. (it != null, defaultVal != null).
2476 * 3) A stream of alternating serialized keys and values.
2477 * (it == null, defaultVal == null).
2478 * 4) A stream of serialized keys. (it == null, defaultVal != null).
2479 *
2480 * It is assumed that the comparator of the TreeMap is already set prior
2481 * to calling this method.
2482 *
2483 * @param size the number of keys (or key-value pairs) to be read from
2484 * the iterator or stream
2485 * @param it If non-null, new entries are created from entries
2486 * or keys read from this iterator.
2487 * @param str If non-null, new entries are created from keys and
2488 * possibly values read from this stream in serialized form.
2489 * Exactly one of it and str should be non-null.
2490 * @param defaultVal if non-null, this default value is used for
2491 * each value in the map. If null, each value is read from
2492 * iterator or stream, as described above.
2493 * @throws java.io.IOException propagated from stream reads. This cannot
2494 * occur if str is null.
2495 * @throws ClassNotFoundException propagated from readObject.
2496 * This cannot occur if str is null.
2497 */
2498 private void buildFromSorted(int size, Iterator<?> it,
2499 java.io.ObjectInputStream str,
2500 V defaultVal)
2501 throws java.io.IOException, ClassNotFoundException {
2502 this.size = size;
2503 root = buildFromSorted(0, 0, size-1, computeRedLevel(size),
2504 it, str, defaultVal);
2505 }
2506
2507 /**
2508 * Recursive "helper method" that does the real work of the
2509 * previous method. Identically named parameters have
2510 * identical definitions. Additional parameters are documented below.
2511 * It is assumed that the comparator and size fields of the TreeMap are
2512 * already set prior to calling this method. (It ignores both fields.)
2513 *
2514 * @param level the current level of tree. Initial call should be 0.
2515 * @param lo the first element index of this subtree. Initial should be 0.
2516 * @param hi the last element index of this subtree. Initial should be
2517 * size-1.
2518 * @param redLevel the level at which nodes should be red.
2519 * Must be equal to computeRedLevel for tree of this size.
2520 */
2521 @SuppressWarnings("unchecked")
2522 private final Entry<K,V> buildFromSorted(int level, int lo, int hi,
2523 int redLevel,
2524 Iterator<?> it,
2525 java.io.ObjectInputStream str,
2526 V defaultVal)
2527 throws java.io.IOException, ClassNotFoundException {
2528 /*
2529 * Strategy: The root is the middlemost element. To get to it, we
2530 * have to first recursively construct the entire left subtree,
2531 * so as to grab all of its elements. We can then proceed with right
2532 * subtree.
2533 *
2534 * The lo and hi arguments are the minimum and maximum
2535 * indices to pull out of the iterator or stream for current subtree.
2536 * They are not actually indexed, we just proceed sequentially,
2537 * ensuring that items are extracted in corresponding order.
2538 */
2539
2540 if (hi < lo) return null;
2541
2542 int mid = (lo + hi) >>> 1;
2543
2544 Entry<K,V> left = null;
2545 if (lo < mid)
2546 left = buildFromSorted(level+1, lo, mid - 1, redLevel,
2547 it, str, defaultVal);
2548
2549 // extract key and/or value from iterator or stream
2550 K key;
2551 V value;
2552 if (it != null) {
2553 if (defaultVal==null) {
2554 Map.Entry<?,?> entry = (Map.Entry<?,?>)it.next();
2555 key = (K)entry.getKey();
2556 value = (V)entry.getValue();
2557 } else {
2558 key = (K)it.next();
2559 value = defaultVal;
2560 }
2561 } else { // use stream
2562 key = (K) str.readObject();
2563 value = (defaultVal != null ? defaultVal : (V) str.readObject());
2564 }
2565
2566 Entry<K,V> middle = new Entry<>(key, value, null);
2567
2568 // color nodes in non-full bottommost level red
2569 if (level == redLevel)
2570 middle.color = RED;
2571
2572 if (left != null) {
2573 middle.left = left;
2574 left.parent = middle;
2575 }
2576
2577 if (mid < hi) {
2578 Entry<K,V> right = buildFromSorted(level+1, mid+1, hi, redLevel,
2579 it, str, defaultVal);
2580 middle.right = right;
2581 right.parent = middle;
2582 }
2583
2584 return middle;
2585 }
2586
2587 /**
2588 * Finds the level down to which to assign all nodes BLACK. This is the
2589 * last `full' level of the complete binary tree produced by buildTree.
2590 * The remaining nodes are colored RED. (This makes a `nice' set of
2591 * color assignments wrt future insertions.) This level number is
2592 * computed by finding the number of splits needed to reach the zeroeth
2593 * node.
2594 *
2595 * @param size the (non-negative) number of keys in the tree to be built
2596 */
2597 private static int computeRedLevel(int size) {
2598 return 31 - Integer.numberOfLeadingZeros(size + 1);
2599 }
2600
2601 /**
2602 * Currently, we support Spliterator-based versions only for the
2603 * full map, in either plain of descending form, otherwise relying
2604 * on defaults because size estimation for submaps would dominate
2605 * costs. The type tests needed to check these for key views are
2606 * not very nice but avoid disrupting existing class
2607 * structures. Callers must use plain default spliterators if this
2608 * returns null.
2609 */
2610 static <K> Spliterator<K> keySpliteratorFor(NavigableMap<K,?> m) {
2611 if (m instanceof TreeMap) {
2612 @SuppressWarnings("unchecked") TreeMap<K,Object> t =
2613 (TreeMap<K,Object>) m;
2614 return t.keySpliterator();
2615 }
2616 if (m instanceof DescendingSubMap) {
2617 @SuppressWarnings("unchecked") DescendingSubMap<K,?> dm =
2618 (DescendingSubMap<K,?>) m;
2619 TreeMap<K,?> tm = dm.m;
2620 if (dm == tm.descendingMap) {
2621 @SuppressWarnings("unchecked") TreeMap<K,Object> t =
2622 (TreeMap<K,Object>) tm;
2623 return t.descendingKeySpliterator();
2624 }
2625 }
2626 @SuppressWarnings("unchecked") NavigableSubMap<K,?> sm =
2627 (NavigableSubMap<K,?>) m;
2628 return sm.keySpliterator();
2629 }
2630
2631 final Spliterator<K> keySpliterator() {
2632 return new KeySpliterator<>(this, null, null, 0, -1, 0);
2633 }
2634
2635 final Spliterator<K> descendingKeySpliterator() {
2636 return new DescendingKeySpliterator<>(this, null, null, 0, -2, 0);
2637 }
2638
2639 /**
2640 * Base class for spliterators. Iteration starts at a given
2641 * origin and continues up to but not including a given fence (or
2642 * null for end). At top-level, for ascending cases, the first
2643 * split uses the root as left-fence/right-origin. From there,
2644 * right-hand splits replace the current fence with its left
2645 * child, also serving as origin for the split-off spliterator.
2646 * Left-hands are symmetric. Descending versions place the origin
2647 * at the end and invert ascending split rules. This base class
2648 * is non-committal about directionality, or whether the top-level
2649 * spliterator covers the whole tree. This means that the actual
2650 * split mechanics are located in subclasses. Some of the subclass
2651 * trySplit methods are identical (except for return types), but
2652 * not nicely factorable.
2653 *
2654 * Currently, subclass versions exist only for the full map
2655 * (including descending keys via its descendingMap). Others are
2656 * possible but currently not worthwhile because submaps require
2657 * O(n) computations to determine size, which substantially limits
2658 * potential speed-ups of using custom Spliterators versus default
2659 * mechanics.
2660 *
2661 * To boostrap initialization, external constructors use
2662 * negative size estimates: -1 for ascend, -2 for descend.
2663 */
2664 static class TreeMapSpliterator<K,V> {
2665 final TreeMap<K,V> tree;
2666 TreeMap.Entry<K,V> current; // traverser; initially first node in range
2667 TreeMap.Entry<K,V> fence; // one past last, or null
2668 int side; // 0: top, -1: is a left split, +1: right
2669 int est; // size estimate (exact only for top-level)
2670 int expectedModCount; // for CME checks
2671
2672 TreeMapSpliterator(TreeMap<K,V> tree,
2673 TreeMap.Entry<K,V> origin, TreeMap.Entry<K,V> fence,
2674 int side, int est, int expectedModCount) {
2675 this.tree = tree;
2676 this.current = origin;
2677 this.fence = fence;
2678 this.side = side;
2679 this.est = est;
2680 this.expectedModCount = expectedModCount;
2681 }
2682
2683 final int getEstimate() { // force initialization
2684 int s; TreeMap<K,V> t;
2685 if ((s = est) < 0) {
2686 if ((t = tree) != null) {
2687 current = (s == -1) ? t.getFirstEntry() : t.getLastEntry();
2688 s = est = t.size;
2689 expectedModCount = t.modCount;
2690 }
2691 else
2692 s = est = 0;
2693 }
2694 return s;
2695 }
2696
2697 public final long estimateSize() {
2698 return (long)getEstimate();
2699 }
2700 }
2701
2702 static final class KeySpliterator<K,V>
2703 extends TreeMapSpliterator<K,V>
2704 implements Spliterator<K> {
2705 KeySpliterator(TreeMap<K,V> tree,
2706 TreeMap.Entry<K,V> origin, TreeMap.Entry<K,V> fence,
2707 int side, int est, int expectedModCount) {
2708 super(tree, origin, fence, side, est, expectedModCount);
2709 }
2710
2711 public KeySpliterator<K,V> trySplit() {
2712 if (est < 0)
2713 getEstimate(); // force initialization
2714 int d = side;
2715 TreeMap.Entry<K,V> e = current, f = fence,
2716 s = ((e == null || e == f) ? null : // empty
2717 (d == 0) ? tree.root : // was top
2718 (d > 0) ? e.right : // was right
2719 (d < 0 && f != null) ? f.left : // was left
2720 null);
2721 if (s != null && s != e && s != f &&
2722 tree.compare(e.key, s.key) < 0) { // e not already past s
2723 side = 1;
2724 return new KeySpliterator<>
2725 (tree, e, current = s, -1, est >>>= 1, expectedModCount);
2726 }
2727 return null;
2728 }
2729
2730 public void forEachRemaining(Consumer<? super K> action) {
2731 if (action == null)
2732 throw new NullPointerException();
2733 if (est < 0)
2734 getEstimate(); // force initialization
2735 TreeMap.Entry<K,V> f = fence, e, p, pl;
2736 if ((e = current) != null && e != f) {
2737 current = f; // exhaust
2738 do {
2739 action.accept(e.key);
2740 if ((p = e.right) != null) {
2741 while ((pl = p.left) != null)
2742 p = pl;
2743 }
2744 else {
2745 while ((p = e.parent) != null && e == p.right)
2746 e = p;
2747 }
2748 } while ((e = p) != null && e != f);
2749 if (tree.modCount != expectedModCount)
2750 throw new ConcurrentModificationException();
2751 }
2752 }
2753
2754 public boolean tryAdvance(Consumer<? super K> action) {
2755 TreeMap.Entry<K,V> e;
2756 if (action == null)
2757 throw new NullPointerException();
2758 if (est < 0)
2759 getEstimate(); // force initialization
2760 if ((e = current) == null || e == fence)
2761 return false;
2762 current = successor(e);
2763 action.accept(e.key);
2764 if (tree.modCount != expectedModCount)
2765 throw new ConcurrentModificationException();
2766 return true;
2767 }
2768
2769 public int characteristics() {
2770 return (side == 0 ? Spliterator.SIZED : 0) |
2771 Spliterator.DISTINCT | Spliterator.SORTED | Spliterator.ORDERED;
2772 }
2773
2774 public final Comparator<? super K> getComparator() {
2775 return tree.comparator;
2776 }
2777
2778 }
2779
2780 static final class DescendingKeySpliterator<K,V>
2781 extends TreeMapSpliterator<K,V>
2782 implements Spliterator<K> {
2783 DescendingKeySpliterator(TreeMap<K,V> tree,
2784 TreeMap.Entry<K,V> origin, TreeMap.Entry<K,V> fence,
2785 int side, int est, int expectedModCount) {
2786 super(tree, origin, fence, side, est, expectedModCount);
2787 }
2788
2789 public DescendingKeySpliterator<K,V> trySplit() {
2790 if (est < 0)
2791 getEstimate(); // force initialization
2792 int d = side;
2793 TreeMap.Entry<K,V> e = current, f = fence,
2794 s = ((e == null || e == f) ? null : // empty
2795 (d == 0) ? tree.root : // was top
2796 (d < 0) ? e.left : // was left
2797 (d > 0 && f != null) ? f.right : // was right
2798 null);
2799 if (s != null && s != e && s != f &&
2800 tree.compare(e.key, s.key) > 0) { // e not already past s
2801 side = 1;
2802 return new DescendingKeySpliterator<>
2803 (tree, e, current = s, -1, est >>>= 1, expectedModCount);
2804 }
2805 return null;
2806 }
2807
2808 public void forEachRemaining(Consumer<? super K> action) {
2809 if (action == null)
2810 throw new NullPointerException();
2811 if (est < 0)
2812 getEstimate(); // force initialization
2813 TreeMap.Entry<K,V> f = fence, e, p, pr;
2814 if ((e = current) != null && e != f) {
2815 current = f; // exhaust
2816 do {
2817 action.accept(e.key);
2818 if ((p = e.left) != null) {
2819 while ((pr = p.right) != null)
2820 p = pr;
2821 }
2822 else {
2823 while ((p = e.parent) != null && e == p.left)
2824 e = p;
2825 }
2826 } while ((e = p) != null && e != f);
2827 if (tree.modCount != expectedModCount)
2828 throw new ConcurrentModificationException();
2829 }
2830 }
2831
2832 public boolean tryAdvance(Consumer<? super K> action) {
2833 TreeMap.Entry<K,V> e;
2834 if (action == null)
2835 throw new NullPointerException();
2836 if (est < 0)
2837 getEstimate(); // force initialization
2838 if ((e = current) == null || e == fence)
2839 return false;
2840 current = predecessor(e);
2841 action.accept(e.key);
2842 if (tree.modCount != expectedModCount)
2843 throw new ConcurrentModificationException();
2844 return true;
2845 }
2846
2847 public int characteristics() {
2848 return (side == 0 ? Spliterator.SIZED : 0) |
2849 Spliterator.DISTINCT | Spliterator.ORDERED;
2850 }
2851 }
2852
2853 static final class ValueSpliterator<K,V>
2854 extends TreeMapSpliterator<K,V>
2855 implements Spliterator<V> {
2856 ValueSpliterator(TreeMap<K,V> tree,
2857 TreeMap.Entry<K,V> origin, TreeMap.Entry<K,V> fence,
2858 int side, int est, int expectedModCount) {
2859 super(tree, origin, fence, side, est, expectedModCount);
2860 }
2861
2862 public ValueSpliterator<K,V> trySplit() {
2863 if (est < 0)
2864 getEstimate(); // force initialization
2865 int d = side;
2866 TreeMap.Entry<K,V> e = current, f = fence,
2867 s = ((e == null || e == f) ? null : // empty
2868 (d == 0) ? tree.root : // was top
2869 (d > 0) ? e.right : // was right
2870 (d < 0 && f != null) ? f.left : // was left
2871 null);
2872 if (s != null && s != e && s != f &&
2873 tree.compare(e.key, s.key) < 0) { // e not already past s
2874 side = 1;
2875 return new ValueSpliterator<>
2876 (tree, e, current = s, -1, est >>>= 1, expectedModCount);
2877 }
2878 return null;
2879 }
2880
2881 public void forEachRemaining(Consumer<? super V> action) {
2882 if (action == null)
2883 throw new NullPointerException();
2884 if (est < 0)
2885 getEstimate(); // force initialization
2886 TreeMap.Entry<K,V> f = fence, e, p, pl;
2887 if ((e = current) != null && e != f) {
2888 current = f; // exhaust
2889 do {
2890 action.accept(e.value);
2891 if ((p = e.right) != null) {
2892 while ((pl = p.left) != null)
2893 p = pl;
2894 }
2895 else {
2896 while ((p = e.parent) != null && e == p.right)
2897 e = p;
2898 }
2899 } while ((e = p) != null && e != f);
2900 if (tree.modCount != expectedModCount)
2901 throw new ConcurrentModificationException();
2902 }
2903 }
2904
2905 public boolean tryAdvance(Consumer<? super V> action) {
2906 TreeMap.Entry<K,V> e;
2907 if (action == null)
2908 throw new NullPointerException();
2909 if (est < 0)
2910 getEstimate(); // force initialization
2911 if ((e = current) == null || e == fence)
2912 return false;
2913 current = successor(e);
2914 action.accept(e.value);
2915 if (tree.modCount != expectedModCount)
2916 throw new ConcurrentModificationException();
2917 return true;
2918 }
2919
2920 public int characteristics() {
2921 return (side == 0 ? Spliterator.SIZED : 0) | Spliterator.ORDERED;
2922 }
2923 }
2924
2925 static final class EntrySpliterator<K,V>
2926 extends TreeMapSpliterator<K,V>
2927 implements Spliterator<Map.Entry<K,V>> {
2928 EntrySpliterator(TreeMap<K,V> tree,
2929 TreeMap.Entry<K,V> origin, TreeMap.Entry<K,V> fence,
2930 int side, int est, int expectedModCount) {
2931 super(tree, origin, fence, side, est, expectedModCount);
2932 }
2933
2934 public EntrySpliterator<K,V> trySplit() {
2935 if (est < 0)
2936 getEstimate(); // force initialization
2937 int d = side;
2938 TreeMap.Entry<K,V> e = current, f = fence,
2939 s = ((e == null || e == f) ? null : // empty
2940 (d == 0) ? tree.root : // was top
2941 (d > 0) ? e.right : // was right
2942 (d < 0 && f != null) ? f.left : // was left
2943 null);
2944 if (s != null && s != e && s != f &&
2945 tree.compare(e.key, s.key) < 0) { // e not already past s
2946 side = 1;
2947 return new EntrySpliterator<>
2948 (tree, e, current = s, -1, est >>>= 1, expectedModCount);
2949 }
2950 return null;
2951 }
2952
2953 public void forEachRemaining(Consumer<? super Map.Entry<K, V>> action) {
2954 if (action == null)
2955 throw new NullPointerException();
2956 if (est < 0)
2957 getEstimate(); // force initialization
2958 TreeMap.Entry<K,V> f = fence, e, p, pl;
2959 if ((e = current) != null && e != f) {
2960 current = f; // exhaust
2961 do {
2962 action.accept(e);
2963 if ((p = e.right) != null) {
2964 while ((pl = p.left) != null)
2965 p = pl;
2966 }
2967 else {
2968 while ((p = e.parent) != null && e == p.right)
2969 e = p;
2970 }
2971 } while ((e = p) != null && e != f);
2972 if (tree.modCount != expectedModCount)
2973 throw new ConcurrentModificationException();
2974 }
2975 }
2976
2977 public boolean tryAdvance(Consumer<? super Map.Entry<K,V>> action) {
2978 TreeMap.Entry<K,V> e;
2979 if (action == null)
2980 throw new NullPointerException();
2981 if (est < 0)
2982 getEstimate(); // force initialization
2983 if ((e = current) == null || e == fence)
2984 return false;
2985 current = successor(e);
2986 action.accept(e);
2987 if (tree.modCount != expectedModCount)
2988 throw new ConcurrentModificationException();
2989 return true;
2990 }
2991
2992 public int characteristics() {
2993 return (side == 0 ? Spliterator.SIZED : 0) |
2994 Spliterator.DISTINCT | Spliterator.SORTED | Spliterator.ORDERED;
2995 }
2996
2997 @Override
2998 public Comparator<Map.Entry<K, V>> getComparator() {
2999 // Adapt or create a key-based comparator
3000 if (tree.comparator != null) {
3001 return Map.Entry.comparingByKey(tree.comparator);
3002 }
3003 else {
3004 return (Comparator<Map.Entry<K, V>> & Serializable) (e1, e2) -> {
3005 @SuppressWarnings("unchecked")
3006 Comparable<? super K> k1 = (Comparable<? super K>) e1.getKey();
3007 return k1.compareTo(e2.getKey());
3008 };
3009 }
3010 }
3011 }
3012 }
3013