1 /* 2 * Copyright (c) 1997, 2014, 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 }