TreeMap.java revision 3733bc930b4f8a02b278dde1109d0cd42f7c4c08
1/* 2 * Copyright (C) 2014 The Android Open Source Project 3 * Copyright (c) 1997, 2013, Oracle and/or its affiliates. All rights reserved. 4 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 5 * 6 * This code is free software; you can redistribute it and/or modify it 7 * under the terms of the GNU General Public License version 2 only, as 8 * published by the Free Software Foundation. Oracle designates this 9 * particular file as subject to the "Classpath" exception as provided 10 * by Oracle in the LICENSE file that accompanied this code. 11 * 12 * This code is distributed in the hope that it will be useful, but WITHOUT 13 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 14 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 15 * version 2 for more details (a copy is included in the LICENSE file that 16 * accompanied this code). 17 * 18 * You should have received a copy of the GNU General Public License version 19 * 2 along with this work; if not, write to the Free Software Foundation, 20 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 21 * 22 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 23 * or visit www.oracle.com if you need additional information or have any 24 * questions. 25 */ 26 27package java.util; 28 29import java.io.Serializable; 30import java.util.function.BiConsumer; 31import java.util.function.BiFunction; 32import java.util.function.Consumer; 33 34/** 35 * A Red-Black tree based {@link NavigableMap} implementation. 36 * The map is sorted according to the {@linkplain Comparable natural 37 * ordering} of its keys, or by a {@link Comparator} provided at map 38 * creation time, depending on which constructor is used. 39 * 40 * <p>This implementation provides guaranteed log(n) time cost for the 41 * {@code containsKey}, {@code get}, {@code put} and {@code remove} 42 * operations. Algorithms are adaptations of those in Cormen, Leiserson, and 43 * Rivest's <em>Introduction to Algorithms</em>. 44 * 45 * <p>Note that the ordering maintained by a tree map, like any sorted map, and 46 * whether or not an explicit comparator is provided, must be <em>consistent 47 * with {@code equals}</em> if this sorted map is to correctly implement the 48 * {@code Map} interface. (See {@code Comparable} or {@code Comparator} for a 49 * precise definition of <em>consistent with equals</em>.) This is so because 50 * the {@code Map} interface is defined in terms of the {@code equals} 51 * operation, but a sorted map performs all key comparisons using its {@code 52 * compareTo} (or {@code compare}) method, so two keys that are deemed equal by 53 * this method are, from the standpoint of the sorted map, equal. The behavior 54 * of a sorted map <em>is</em> well-defined even if its ordering is 55 * inconsistent with {@code equals}; it just fails to obey the general contract 56 * of the {@code Map} interface. 57 * 58 * <p><strong>Note that this implementation is not synchronized.</strong> 59 * If multiple threads access a map concurrently, and at least one of the 60 * threads modifies the map structurally, it <em>must</em> be synchronized 61 * externally. (A structural modification is any operation that adds or 62 * deletes one or more mappings; merely changing the value associated 63 * with an existing key is not a structural modification.) This is 64 * typically accomplished by synchronizing on some object that naturally 65 * encapsulates the map. 66 * If no such object exists, the map should be "wrapped" using the 67 * {@link Collections#synchronizedSortedMap Collections.synchronizedSortedMap} 68 * method. This is best done at creation time, to prevent accidental 69 * unsynchronized access to the map: <pre> 70 * SortedMap m = Collections.synchronizedSortedMap(new TreeMap(...));</pre> 71 * 72 * <p>The iterators returned by the {@code iterator} method of the collections 73 * returned by all of this class's "collection view methods" are 74 * <em>fail-fast</em>: if the map is structurally modified at any time after 75 * the iterator is created, in any way except through the iterator's own 76 * {@code remove} method, the iterator will throw a {@link 77 * ConcurrentModificationException}. Thus, in the face of concurrent 78 * modification, the iterator fails quickly and cleanly, rather than risking 79 * arbitrary, non-deterministic behavior at an undetermined time in the future. 80 * 81 * <p>Note that the fail-fast behavior of an iterator cannot be guaranteed 82 * as it is, generally speaking, impossible to make any hard guarantees in the 83 * presence of unsynchronized concurrent modification. Fail-fast iterators 84 * throw {@code ConcurrentModificationException} on a best-effort basis. 85 * Therefore, it would be wrong to write a program that depended on this 86 * exception for its correctness: <em>the fail-fast behavior of iterators 87 * should be used only to detect bugs.</em> 88 * 89 * <p>All {@code Map.Entry} pairs returned by methods in this class 90 * and its views represent snapshots of mappings at the time they were 91 * produced. They do <strong>not</strong> support the {@code Entry.setValue} 92 * method. (Note however that it is possible to change mappings in the 93 * associated map using {@code put}.) 94 * 95 * <p>This class is a member of the 96 * <a href="{@docRoot}openjdk-redirect.html?v=8&path=/technotes/guides/collections/index.html"> 97 * Java Collections Framework</a>. 98 * 99 * @param <K> the type of keys maintained by this map 100 * @param <V> the type of mapped values 101 * 102 * @author Josh Bloch and Doug Lea 103 * @see Map 104 * @see HashMap 105 * @see Hashtable 106 * @see Comparable 107 * @see Comparator 108 * @see Collection 109 * @since 1.2 110 */ 111 112public class TreeMap<K,V> 113 extends AbstractMap<K,V> 114 implements NavigableMap<K,V>, Cloneable, java.io.Serializable 115{ 116 /** 117 * The comparator used to maintain order in this tree map, or 118 * null if it uses the natural ordering of its keys. 119 * 120 * @serial 121 */ 122 private final Comparator<? super K> comparator; 123 124 private transient TreeMapEntry<K,V> root = null; 125 126 /** 127 * The number of entries in the tree 128 */ 129 private transient int size = 0; 130 131 /** 132 * The number of structural modifications to the tree. 133 */ 134 private transient int modCount = 0; 135 136 /** 137 * Constructs a new, empty tree map, using the natural ordering of its 138 * keys. All keys inserted into the map must implement the {@link 139 * Comparable} interface. Furthermore, all such keys must be 140 * <em>mutually comparable</em>: {@code k1.compareTo(k2)} must not throw 141 * a {@code ClassCastException} for any keys {@code k1} and 142 * {@code k2} in the map. If the user attempts to put a key into the 143 * map that violates this constraint (for example, the user attempts to 144 * put a string key into a map whose keys are integers), the 145 * {@code put(Object key, Object value)} call will throw a 146 * {@code ClassCastException}. 147 */ 148 public TreeMap() { 149 comparator = null; 150 } 151 152 /** 153 * Constructs a new, empty tree map, ordered according to the given 154 * comparator. All keys inserted into the map must be <em>mutually 155 * comparable</em> by the given comparator: {@code comparator.compare(k1, 156 * k2)} must not throw a {@code ClassCastException} for any keys 157 * {@code k1} and {@code k2} in the map. If the user attempts to put 158 * a key into the map that violates this constraint, the {@code put(Object 159 * key, Object value)} call will throw a 160 * {@code ClassCastException}. 161 * 162 * @param comparator the comparator that will be used to order this map. 163 * If {@code null}, the {@linkplain Comparable natural 164 * ordering} of the keys will be used. 165 */ 166 public TreeMap(Comparator<? super K> comparator) { 167 this.comparator = comparator; 168 } 169 170 /** 171 * Constructs a new tree map containing the same mappings as the given 172 * map, ordered according to the <em>natural ordering</em> of its keys. 173 * All keys inserted into the new map must implement the {@link 174 * Comparable} interface. Furthermore, all such keys must be 175 * <em>mutually comparable</em>: {@code k1.compareTo(k2)} must not throw 176 * a {@code ClassCastException} for any keys {@code k1} and 177 * {@code k2} in the map. This method runs in n*log(n) time. 178 * 179 * @param m the map whose mappings are to be placed in this map 180 * @throws ClassCastException if the keys in m are not {@link Comparable}, 181 * or are not mutually comparable 182 * @throws NullPointerException if the specified map is null 183 */ 184 public TreeMap(Map<? extends K, ? extends V> m) { 185 comparator = null; 186 putAll(m); 187 } 188 189 /** 190 * Constructs a new tree map containing the same mappings and 191 * using the same ordering as the specified sorted map. This 192 * method runs in linear time. 193 * 194 * @param m the sorted map whose mappings are to be placed in this map, 195 * and whose comparator is to be used to sort this map 196 * @throws NullPointerException if the specified map is null 197 */ 198 public TreeMap(SortedMap<K, ? extends V> m) { 199 comparator = m.comparator(); 200 try { 201 buildFromSorted(m.size(), m.entrySet().iterator(), null, null); 202 } catch (java.io.IOException cannotHappen) { 203 } catch (ClassNotFoundException cannotHappen) { 204 } 205 } 206 207 208 // Query Operations 209 210 /** 211 * Returns the number of key-value mappings in this map. 212 * 213 * @return the number of key-value mappings in this map 214 */ 215 public int size() { 216 return size; 217 } 218 219 /** 220 * Returns {@code true} if this map contains a mapping for the specified 221 * key. 222 * 223 * @param key key whose presence in this map is to be tested 224 * @return {@code true} if this map contains a mapping for the 225 * specified key 226 * @throws ClassCastException if the specified key cannot be compared 227 * with the keys currently in the map 228 * @throws NullPointerException if the specified key is null 229 * and this map uses natural ordering, or its comparator 230 * does not permit null keys 231 */ 232 public boolean containsKey(Object key) { 233 return getEntry(key) != null; 234 } 235 236 /** 237 * Returns {@code true} if this map maps one or more keys to the 238 * specified value. More formally, returns {@code true} if and only if 239 * this map contains at least one mapping to a value {@code v} such 240 * that {@code (value==null ? v==null : value.equals(v))}. This 241 * operation will probably require time linear in the map size for 242 * most implementations. 243 * 244 * @param value value whose presence in this map is to be tested 245 * @return {@code true} if a mapping to {@code value} exists; 246 * {@code false} otherwise 247 * @since 1.2 248 */ 249 public boolean containsValue(Object value) { 250 for (TreeMapEntry<K,V> e = getFirstEntry(); e != null; e = successor(e)) 251 if (valEquals(value, e.value)) 252 return true; 253 return false; 254 } 255 256 /** 257 * Returns the value to which the specified key is mapped, 258 * or {@code null} if this map contains no mapping for the key. 259 * 260 * <p>More formally, if this map contains a mapping from a key 261 * {@code k} to a value {@code v} such that {@code key} compares 262 * equal to {@code k} according to the map's ordering, then this 263 * method returns {@code v}; otherwise it returns {@code null}. 264 * (There can be at most one such mapping.) 265 * 266 * <p>A return value of {@code null} does not <em>necessarily</em> 267 * indicate that the map contains no mapping for the key; it's also 268 * possible that the map explicitly maps the key to {@code null}. 269 * The {@link #containsKey containsKey} operation may be used to 270 * distinguish these two cases. 271 * 272 * @throws ClassCastException if the specified key cannot be compared 273 * with the keys currently in the map 274 * @throws NullPointerException if the specified key is null 275 * and this map uses natural ordering, or its comparator 276 * does not permit null keys 277 */ 278 public V get(Object key) { 279 TreeMapEntry<K,V> p = getEntry(key); 280 return (p==null ? null : p.value); 281 } 282 283 public Comparator<? super K> comparator() { 284 return comparator; 285 } 286 287 /** 288 * @throws NoSuchElementException {@inheritDoc} 289 */ 290 public K firstKey() { 291 return key(getFirstEntry()); 292 } 293 294 /** 295 * @throws NoSuchElementException {@inheritDoc} 296 */ 297 public K lastKey() { 298 return key(getLastEntry()); 299 } 300 301 /** 302 * Copies all of the mappings from the specified map to this map. 303 * These mappings replace any mappings that this map had for any 304 * of the keys currently in the specified map. 305 * 306 * @param map mappings to be stored in this map 307 * @throws ClassCastException if the class of a key or value in 308 * the specified map prevents it from being stored in this map 309 * @throws NullPointerException if the specified map is null or 310 * the specified map contains a null key and this map does not 311 * permit null keys 312 */ 313 public void putAll(Map<? extends K, ? extends V> map) { 314 int mapSize = map.size(); 315 if (size==0 && mapSize!=0 && map instanceof SortedMap) { 316 Comparator<?> c = ((SortedMap<?,?>)map).comparator(); 317 if (c == comparator || (c != null && c.equals(comparator))) { 318 ++modCount; 319 try { 320 buildFromSorted(mapSize, map.entrySet().iterator(), 321 null, null); 322 } catch (java.io.IOException cannotHappen) { 323 } catch (ClassNotFoundException cannotHappen) { 324 } 325 return; 326 } 327 } 328 super.putAll(map); 329 } 330 331 /** 332 * Returns this map's entry for the given key, or {@code null} if the map 333 * does not contain an entry for the key. 334 * 335 * @return this map's entry for the given key, or {@code null} if the map 336 * does not contain an entry for the key 337 * @throws ClassCastException if the specified key cannot be compared 338 * with the keys currently in the map 339 * @throws NullPointerException if the specified key is null 340 * and this map uses natural ordering, or its comparator 341 * does not permit null keys 342 */ 343 final TreeMapEntry<K,V> getEntry(Object key) { 344 // Offload comparator-based version for sake of performance 345 if (comparator != null) 346 return getEntryUsingComparator(key); 347 if (key == null) 348 throw new NullPointerException(); 349 @SuppressWarnings("unchecked") 350 Comparable<? super K> k = (Comparable<? super K>) key; 351 TreeMapEntry<K,V> p = root; 352 while (p != null) { 353 int cmp = k.compareTo(p.key); 354 if (cmp < 0) 355 p = p.left; 356 else if (cmp > 0) 357 p = p.right; 358 else 359 return p; 360 } 361 return null; 362 } 363 364 /** 365 * Version of getEntry using comparator. Split off from getEntry 366 * for performance. (This is not worth doing for most methods, 367 * that are less dependent on comparator performance, but is 368 * worthwhile here.) 369 */ 370 final TreeMapEntry<K,V> getEntryUsingComparator(Object key) { 371 @SuppressWarnings("unchecked") 372 K k = (K) key; 373 Comparator<? super K> cpr = comparator; 374 if (cpr != null) { 375 TreeMapEntry<K,V> p = root; 376 while (p != null) { 377 int cmp = cpr.compare(k, p.key); 378 if (cmp < 0) 379 p = p.left; 380 else if (cmp > 0) 381 p = p.right; 382 else 383 return p; 384 } 385 } 386 return null; 387 } 388 389 /** 390 * Gets the entry corresponding to the specified key; if no such entry 391 * exists, returns the entry for the least key greater than the specified 392 * key; if no such entry exists (i.e., the greatest key in the Tree is less 393 * than the specified key), returns {@code null}. 394 */ 395 final TreeMapEntry<K,V> getCeilingEntry(K key) { 396 TreeMapEntry<K,V> p = root; 397 while (p != null) { 398 int cmp = compare(key, p.key); 399 if (cmp < 0) { 400 if (p.left != null) 401 p = p.left; 402 else 403 return p; 404 } else if (cmp > 0) { 405 if (p.right != null) { 406 p = p.right; 407 } else { 408 TreeMapEntry<K,V> parent = p.parent; 409 TreeMapEntry<K,V> ch = p; 410 while (parent != null && ch == parent.right) { 411 ch = parent; 412 parent = parent.parent; 413 } 414 return parent; 415 } 416 } else 417 return p; 418 } 419 return null; 420 } 421 422 /** 423 * Gets the entry corresponding to the specified key; if no such entry 424 * exists, returns the entry for the greatest key less than the specified 425 * key; if no such entry exists, returns {@code null}. 426 */ 427 final TreeMapEntry<K,V> getFloorEntry(K key) { 428 TreeMapEntry<K,V> p = root; 429 while (p != null) { 430 int cmp = compare(key, p.key); 431 if (cmp > 0) { 432 if (p.right != null) 433 p = p.right; 434 else 435 return p; 436 } else if (cmp < 0) { 437 if (p.left != null) { 438 p = p.left; 439 } else { 440 TreeMapEntry<K,V> parent = p.parent; 441 TreeMapEntry<K,V> ch = p; 442 while (parent != null && ch == parent.left) { 443 ch = parent; 444 parent = parent.parent; 445 } 446 return parent; 447 } 448 } else 449 return p; 450 451 } 452 return null; 453 } 454 455 /** 456 * Gets the entry for the least key greater than the specified 457 * key; if no such entry exists, returns the entry for the least 458 * key greater than the specified key; if no such entry exists 459 * returns {@code null}. 460 */ 461 final TreeMapEntry<K,V> getHigherEntry(K key) { 462 TreeMapEntry<K,V> p = root; 463 while (p != null) { 464 int cmp = compare(key, p.key); 465 if (cmp < 0) { 466 if (p.left != null) 467 p = p.left; 468 else 469 return p; 470 } else { 471 if (p.right != null) { 472 p = p.right; 473 } else { 474 TreeMapEntry<K,V> parent = p.parent; 475 TreeMapEntry<K,V> ch = p; 476 while (parent != null && ch == parent.right) { 477 ch = parent; 478 parent = parent.parent; 479 } 480 return parent; 481 } 482 } 483 } 484 return null; 485 } 486 487 /** 488 * Returns the entry for the greatest key less than the specified key; if 489 * no such entry exists (i.e., the least key in the Tree is greater than 490 * the specified key), returns {@code null}. 491 */ 492 final TreeMapEntry<K,V> getLowerEntry(K key) { 493 TreeMapEntry<K,V> p = root; 494 while (p != null) { 495 int cmp = compare(key, p.key); 496 if (cmp > 0) { 497 if (p.right != null) 498 p = p.right; 499 else 500 return p; 501 } else { 502 if (p.left != null) { 503 p = p.left; 504 } else { 505 TreeMapEntry<K,V> parent = p.parent; 506 TreeMapEntry<K,V> ch = p; 507 while (parent != null && ch == parent.left) { 508 ch = parent; 509 parent = parent.parent; 510 } 511 return parent; 512 } 513 } 514 } 515 return null; 516 } 517 518 /** 519 * Associates the specified value with the specified key in this map. 520 * If the map previously contained a mapping for the key, the old 521 * value is replaced. 522 * 523 * @param key key with which the specified value is to be associated 524 * @param value value to be associated with the specified key 525 * 526 * @return the previous value associated with {@code key}, or 527 * {@code null} if there was no mapping for {@code key}. 528 * (A {@code null} return can also indicate that the map 529 * previously associated {@code null} with {@code key}.) 530 * @throws ClassCastException if the specified key cannot be compared 531 * with the keys currently in the map 532 * @throws NullPointerException if the specified key is null 533 * and this map uses natural ordering, or its comparator 534 * does not permit null keys 535 */ 536 public V put(K key, V value) { 537 TreeMapEntry<K,V> t = root; 538 if (t == null) { 539 compare(key, key); // type (and possibly null) check 540 541 root = new TreeMapEntry<>(key, value, null); 542 size = 1; 543 modCount++; 544 return null; 545 } 546 int cmp; 547 TreeMapEntry<K,V> parent; 548 // split comparator and comparable paths 549 Comparator<? super K> cpr = comparator; 550 if (cpr != null) { 551 do { 552 parent = t; 553 cmp = cpr.compare(key, t.key); 554 if (cmp < 0) 555 t = t.left; 556 else if (cmp > 0) 557 t = t.right; 558 else 559 return t.setValue(value); 560 } while (t != null); 561 } 562 else { 563 if (key == null) 564 throw new NullPointerException(); 565 @SuppressWarnings("unchecked") 566 Comparable<? super K> k = (Comparable<? super K>) key; 567 do { 568 parent = t; 569 cmp = k.compareTo(t.key); 570 if (cmp < 0) 571 t = t.left; 572 else if (cmp > 0) 573 t = t.right; 574 else 575 return t.setValue(value); 576 } while (t != null); 577 } 578 TreeMapEntry<K,V> e = new TreeMapEntry<>(key, value, parent); 579 if (cmp < 0) 580 parent.left = e; 581 else 582 parent.right = e; 583 fixAfterInsertion(e); 584 size++; 585 modCount++; 586 return null; 587 } 588 589 /** 590 * Removes the mapping for this key from this TreeMap if present. 591 * 592 * @param key key for which mapping should be removed 593 * @return the previous value associated with {@code key}, or 594 * {@code null} if there was no mapping for {@code key}. 595 * (A {@code null} return can also indicate that the map 596 * previously associated {@code null} with {@code key}.) 597 * @throws ClassCastException if the specified key cannot be compared 598 * with the keys currently in the map 599 * @throws NullPointerException if the specified key is null 600 * and this map uses natural ordering, or its comparator 601 * does not permit null keys 602 */ 603 public V remove(Object key) { 604 TreeMapEntry<K,V> p = getEntry(key); 605 if (p == null) 606 return null; 607 608 V oldValue = p.value; 609 deleteEntry(p); 610 return oldValue; 611 } 612 613 /** 614 * Removes all of the mappings from this map. 615 * The map will be empty after this call returns. 616 */ 617 public void clear() { 618 modCount++; 619 size = 0; 620 root = null; 621 } 622 623 /** 624 * Returns a shallow copy of this {@code TreeMap} instance. (The keys and 625 * values themselves are not cloned.) 626 * 627 * @return a shallow copy of this map 628 */ 629 public Object clone() { 630 TreeMap<?,?> clone; 631 try { 632 clone = (TreeMap<?,?>) super.clone(); 633 } catch (CloneNotSupportedException e) { 634 throw new InternalError(e); 635 } 636 637 // Put clone into "virgin" state (except for comparator) 638 clone.root = null; 639 clone.size = 0; 640 clone.modCount = 0; 641 clone.entrySet = null; 642 clone.navigableKeySet = null; 643 clone.descendingMap = null; 644 645 // Initialize clone with our mappings 646 try { 647 clone.buildFromSorted(size, entrySet().iterator(), null, null); 648 } catch (java.io.IOException cannotHappen) { 649 } catch (ClassNotFoundException cannotHappen) { 650 } 651 652 return clone; 653 } 654 655 // NavigableMap API methods 656 657 /** 658 * @since 1.6 659 */ 660 public Map.Entry<K,V> firstEntry() { 661 return exportEntry(getFirstEntry()); 662 } 663 664 /** 665 * @since 1.6 666 */ 667 public Map.Entry<K,V> lastEntry() { 668 return exportEntry(getLastEntry()); 669 } 670 671 /** 672 * @since 1.6 673 */ 674 public Map.Entry<K,V> pollFirstEntry() { 675 TreeMapEntry<K,V> p = getFirstEntry(); 676 Map.Entry<K,V> result = exportEntry(p); 677 if (p != null) 678 deleteEntry(p); 679 return result; 680 } 681 682 /** 683 * @since 1.6 684 */ 685 public Map.Entry<K,V> pollLastEntry() { 686 TreeMapEntry<K,V> p = getLastEntry(); 687 Map.Entry<K,V> result = exportEntry(p); 688 if (p != null) 689 deleteEntry(p); 690 return result; 691 } 692 693 /** 694 * @throws ClassCastException {@inheritDoc} 695 * @throws NullPointerException if the specified key is null 696 * and this map uses natural ordering, or its comparator 697 * does not permit null keys 698 * @since 1.6 699 */ 700 public Map.Entry<K,V> lowerEntry(K key) { 701 return exportEntry(getLowerEntry(key)); 702 } 703 704 /** 705 * @throws ClassCastException {@inheritDoc} 706 * @throws NullPointerException if the specified key is null 707 * and this map uses natural ordering, or its comparator 708 * does not permit null keys 709 * @since 1.6 710 */ 711 public K lowerKey(K key) { 712 return keyOrNull(getLowerEntry(key)); 713 } 714 715 /** 716 * @throws ClassCastException {@inheritDoc} 717 * @throws NullPointerException if the specified key is null 718 * and this map uses natural ordering, or its comparator 719 * does not permit null keys 720 * @since 1.6 721 */ 722 public Map.Entry<K,V> floorEntry(K key) { 723 return exportEntry(getFloorEntry(key)); 724 } 725 726 /** 727 * @throws ClassCastException {@inheritDoc} 728 * @throws NullPointerException if the specified key is null 729 * and this map uses natural ordering, or its comparator 730 * does not permit null keys 731 * @since 1.6 732 */ 733 public K floorKey(K key) { 734 return keyOrNull(getFloorEntry(key)); 735 } 736 737 /** 738 * @throws ClassCastException {@inheritDoc} 739 * @throws NullPointerException if the specified key is null 740 * and this map uses natural ordering, or its comparator 741 * does not permit null keys 742 * @since 1.6 743 */ 744 public Map.Entry<K,V> ceilingEntry(K key) { 745 return exportEntry(getCeilingEntry(key)); 746 } 747 748 /** 749 * @throws ClassCastException {@inheritDoc} 750 * @throws NullPointerException if the specified key is null 751 * and this map uses natural ordering, or its comparator 752 * does not permit null keys 753 * @since 1.6 754 */ 755 public K ceilingKey(K key) { 756 return keyOrNull(getCeilingEntry(key)); 757 } 758 759 /** 760 * @throws ClassCastException {@inheritDoc} 761 * @throws NullPointerException if the specified key is null 762 * and this map uses natural ordering, or its comparator 763 * does not permit null keys 764 * @since 1.6 765 */ 766 public Map.Entry<K,V> higherEntry(K key) { 767 return exportEntry(getHigherEntry(key)); 768 } 769 770 /** 771 * @throws ClassCastException {@inheritDoc} 772 * @throws NullPointerException if the specified key is null 773 * and this map uses natural ordering, or its comparator 774 * does not permit null keys 775 * @since 1.6 776 */ 777 public K higherKey(K key) { 778 return keyOrNull(getHigherEntry(key)); 779 } 780 781 // Views 782 783 /** 784 * Fields initialized to contain an instance of the entry set view 785 * the first time this view is requested. Views are stateless, so 786 * there's no reason to create more than one. 787 */ 788 private transient EntrySet entrySet = null; 789 private transient KeySet<K> navigableKeySet = null; 790 private transient NavigableMap<K,V> descendingMap = null; 791 792 /** 793 * Returns a {@link Set} view of the keys contained in this map. 794 * 795 * <p>The set's iterator returns the keys in ascending order. 796 * The set's spliterator is 797 * <em><a href="Spliterator.html#binding">late-binding</a></em>, 798 * <em>fail-fast</em>, and additionally reports {@link Spliterator#SORTED} 799 * and {@link Spliterator#ORDERED} with an encounter order that is ascending 800 * key order. The spliterator's comparator (see 801 * {@link java.util.Spliterator#getComparator()}) is {@code null} if 802 * the tree map's comparator (see {@link #comparator()}) is {@code null}. 803 * Otherwise, the spliterator's comparator is the same as or imposes the 804 * same total ordering as the tree map's comparator. 805 * 806 * <p>The set is backed by the map, so changes to the map are 807 * reflected in the set, and vice-versa. If the map is modified 808 * while an iteration over the set is in progress (except through 809 * the iterator's own {@code remove} operation), the results of 810 * the iteration are undefined. The set supports element removal, 811 * which removes the corresponding mapping from the map, via the 812 * {@code Iterator.remove}, {@code Set.remove}, 813 * {@code removeAll}, {@code retainAll}, and {@code clear} 814 * operations. It does not support the {@code add} or {@code addAll} 815 * operations. 816 */ 817 public Set<K> keySet() { 818 return navigableKeySet(); 819 } 820 821 /** 822 * @since 1.6 823 */ 824 public NavigableSet<K> navigableKeySet() { 825 KeySet<K> nks = navigableKeySet; 826 return (nks != null) ? nks : (navigableKeySet = new KeySet<>(this)); 827 } 828 829 /** 830 * @since 1.6 831 */ 832 public NavigableSet<K> descendingKeySet() { 833 return descendingMap().navigableKeySet(); 834 } 835 836 /** 837 * Returns a {@link Collection} view of the values contained in this map. 838 * 839 * <p>The collection's iterator returns the values in ascending order 840 * of the corresponding keys. The collection's spliterator is 841 * <em><a href="Spliterator.html#binding">late-binding</a></em>, 842 * <em>fail-fast</em>, and additionally reports {@link Spliterator#ORDERED} 843 * with an encounter order that is ascending order of the corresponding 844 * keys. 845 * 846 * <p>The collection is backed by the map, so changes to the map are 847 * reflected in the collection, and vice-versa. If the map is 848 * modified while an iteration over the collection is in progress 849 * (except through the iterator's own {@code remove} operation), 850 * the results of the iteration are undefined. The collection 851 * supports element removal, which removes the corresponding 852 * mapping from the map, via the {@code Iterator.remove}, 853 * {@code Collection.remove}, {@code removeAll}, 854 * {@code retainAll} and {@code clear} operations. It does not 855 * support the {@code add} or {@code addAll} operations. 856 */ 857 public Collection<V> values() { 858 Collection<V> vs = values; 859 return (vs != null) ? vs : (values = new Values()); 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 * sets'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 TreeMapEntry<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 TreeMapEntry<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 (TreeMapEntry<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 (TreeMapEntry<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 (TreeMapEntry<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<K,V>(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<K,V> entry = (Map.Entry<K,V>) o; 1067 V value = entry.getValue(); 1068 TreeMapEntry<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<K,V> entry = (Map.Entry<K,V>) o; 1076 V value = entry.getValue(); 1077 TreeMapEntry<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<K,V>(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 TreeMapEntry<K,V> next; 1190 TreeMapEntry<K,V> lastReturned; 1191 int expectedModCount; 1192 1193 PrivateEntryIterator(TreeMapEntry<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 TreeMapEntry<K,V> nextEntry() { 1204 TreeMapEntry<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 TreeMapEntry<K,V> prevEntry() { 1215 TreeMapEntry<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(TreeMapEntry<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(TreeMapEntry<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(TreeMapEntry<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(TreeMapEntry<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(TreeMapEntry<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(TreeMapEntry<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(TreeMapEntry<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 // Android-changed: Explicitly add a serialVersionUID so that we're serialization 1343 // compatible with the Java-7 version of this class. Several new methods were added 1344 // in Java-8 but none of them have any bearing on the serialized format of the class 1345 // or require any additional state to be preserved. 1346 private static final long serialVersionUID = 2765629423043303731L; 1347 1348 /** 1349 * The backing map. 1350 */ 1351 final TreeMap<K,V> m; 1352 1353 /** 1354 * Endpoints are represented as triples (fromStart, lo, 1355 * loInclusive) and (toEnd, hi, hiInclusive). If fromStart is 1356 * true, then the low (absolute) bound is the start of the 1357 * backing map, and the other values are ignored. Otherwise, 1358 * if loInclusive is true, lo is the inclusive bound, else lo 1359 * is the exclusive bound. Similarly for the upper bound. 1360 */ 1361 final K lo, hi; 1362 final boolean fromStart, toEnd; 1363 final boolean loInclusive, hiInclusive; 1364 1365 NavigableSubMap(TreeMap<K,V> m, 1366 boolean fromStart, K lo, boolean loInclusive, 1367 boolean toEnd, K hi, boolean hiInclusive) { 1368 if (!fromStart && !toEnd) { 1369 if (m.compare(lo, hi) > 0) 1370 throw new IllegalArgumentException("fromKey > toKey"); 1371 } else { 1372 if (!fromStart) // type check 1373 m.compare(lo, lo); 1374 if (!toEnd) 1375 m.compare(hi, hi); 1376 } 1377 1378 this.m = m; 1379 this.fromStart = fromStart; 1380 this.lo = lo; 1381 this.loInclusive = loInclusive; 1382 this.toEnd = toEnd; 1383 this.hi = hi; 1384 this.hiInclusive = hiInclusive; 1385 } 1386 1387 // internal utilities 1388 1389 final boolean tooLow(Object key) { 1390 if (!fromStart) { 1391 int c = m.compare(key, lo); 1392 if (c < 0 || (c == 0 && !loInclusive)) 1393 return true; 1394 } 1395 return false; 1396 } 1397 1398 final boolean tooHigh(Object key) { 1399 if (!toEnd) { 1400 int c = m.compare(key, hi); 1401 if (c > 0 || (c == 0 && !hiInclusive)) 1402 return true; 1403 } 1404 return false; 1405 } 1406 1407 final boolean inRange(Object key) { 1408 return !tooLow(key) && !tooHigh(key); 1409 } 1410 1411 final boolean inClosedRange(Object key) { 1412 return (fromStart || m.compare(key, lo) >= 0) 1413 && (toEnd || m.compare(hi, key) >= 0); 1414 } 1415 1416 final boolean inRange(Object key, boolean inclusive) { 1417 return inclusive ? inRange(key) : inClosedRange(key); 1418 } 1419 1420 /* 1421 * Absolute versions of relation operations. 1422 * Subclasses map to these using like-named "sub" 1423 * versions that invert senses for descending maps 1424 */ 1425 1426 final TreeMapEntry<K,V> absLowest() { 1427 TreeMapEntry<K,V> e = 1428 (fromStart ? m.getFirstEntry() : 1429 (loInclusive ? m.getCeilingEntry(lo) : 1430 m.getHigherEntry(lo))); 1431 return (e == null || tooHigh(e.key)) ? null : e; 1432 } 1433 1434 final TreeMapEntry<K,V> absHighest() { 1435 TreeMapEntry<K,V> e = 1436 (toEnd ? m.getLastEntry() : 1437 (hiInclusive ? m.getFloorEntry(hi) : 1438 m.getLowerEntry(hi))); 1439 return (e == null || tooLow(e.key)) ? null : e; 1440 } 1441 1442 final TreeMapEntry<K,V> absCeiling(K key) { 1443 if (tooLow(key)) 1444 return absLowest(); 1445 TreeMapEntry<K,V> e = m.getCeilingEntry(key); 1446 return (e == null || tooHigh(e.key)) ? null : e; 1447 } 1448 1449 final TreeMapEntry<K,V> absHigher(K key) { 1450 if (tooLow(key)) 1451 return absLowest(); 1452 TreeMapEntry<K,V> e = m.getHigherEntry(key); 1453 return (e == null || tooHigh(e.key)) ? null : e; 1454 } 1455 1456 final TreeMapEntry<K,V> absFloor(K key) { 1457 if (tooHigh(key)) 1458 return absHighest(); 1459 TreeMapEntry<K,V> e = m.getFloorEntry(key); 1460 return (e == null || tooLow(e.key)) ? null : e; 1461 } 1462 1463 final TreeMapEntry<K,V> absLower(K key) { 1464 if (tooHigh(key)) 1465 return absHighest(); 1466 TreeMapEntry<K,V> e = m.getLowerEntry(key); 1467 return (e == null || tooLow(e.key)) ? null : e; 1468 } 1469 1470 /** Returns the absolute high fence for ascending traversal */ 1471 final TreeMapEntry<K,V> absHighFence() { 1472 return (toEnd ? null : (hiInclusive ? 1473 m.getHigherEntry(hi) : 1474 m.getCeilingEntry(hi))); 1475 } 1476 1477 /** Return the absolute low fence for descending traversal */ 1478 final TreeMapEntry<K,V> absLowFence() { 1479 return (fromStart ? null : (loInclusive ? 1480 m.getLowerEntry(lo) : 1481 m.getFloorEntry(lo))); 1482 } 1483 1484 // Abstract methods defined in ascending vs descending classes 1485 // These relay to the appropriate absolute versions 1486 1487 abstract TreeMapEntry<K,V> subLowest(); 1488 abstract TreeMapEntry<K,V> subHighest(); 1489 abstract TreeMapEntry<K,V> subCeiling(K key); 1490 abstract TreeMapEntry<K,V> subHigher(K key); 1491 abstract TreeMapEntry<K,V> subFloor(K key); 1492 abstract TreeMapEntry<K,V> subLower(K key); 1493 1494 /** Returns ascending iterator from the perspective of this submap */ 1495 abstract Iterator<K> keyIterator(); 1496 1497 abstract Spliterator<K> keySpliterator(); 1498 1499 /** Returns descending iterator from the perspective of this submap */ 1500 abstract Iterator<K> descendingKeyIterator(); 1501 1502 // public methods 1503 1504 public boolean isEmpty() { 1505 return (fromStart && toEnd) ? m.isEmpty() : entrySet().isEmpty(); 1506 } 1507 1508 public int size() { 1509 return (fromStart && toEnd) ? m.size() : entrySet().size(); 1510 } 1511 1512 public final boolean containsKey(Object key) { 1513 return inRange(key) && m.containsKey(key); 1514 } 1515 1516 public final V put(K key, V value) { 1517 if (!inRange(key)) 1518 throw new IllegalArgumentException("key out of range"); 1519 return m.put(key, value); 1520 } 1521 1522 public final V get(Object key) { 1523 return !inRange(key) ? null : m.get(key); 1524 } 1525 1526 public final V remove(Object key) { 1527 return !inRange(key) ? null : m.remove(key); 1528 } 1529 1530 public final Map.Entry<K,V> ceilingEntry(K key) { 1531 return exportEntry(subCeiling(key)); 1532 } 1533 1534 public final K ceilingKey(K key) { 1535 return keyOrNull(subCeiling(key)); 1536 } 1537 1538 public final Map.Entry<K,V> higherEntry(K key) { 1539 return exportEntry(subHigher(key)); 1540 } 1541 1542 public final K higherKey(K key) { 1543 return keyOrNull(subHigher(key)); 1544 } 1545 1546 public final Map.Entry<K,V> floorEntry(K key) { 1547 return exportEntry(subFloor(key)); 1548 } 1549 1550 public final K floorKey(K key) { 1551 return keyOrNull(subFloor(key)); 1552 } 1553 1554 public final Map.Entry<K,V> lowerEntry(K key) { 1555 return exportEntry(subLower(key)); 1556 } 1557 1558 public final K lowerKey(K key) { 1559 return keyOrNull(subLower(key)); 1560 } 1561 1562 public final K firstKey() { 1563 return key(subLowest()); 1564 } 1565 1566 public final K lastKey() { 1567 return key(subHighest()); 1568 } 1569 1570 public final Map.Entry<K,V> firstEntry() { 1571 return exportEntry(subLowest()); 1572 } 1573 1574 public final Map.Entry<K,V> lastEntry() { 1575 return exportEntry(subHighest()); 1576 } 1577 1578 public final Map.Entry<K,V> pollFirstEntry() { 1579 TreeMapEntry<K,V> e = subLowest(); 1580 Map.Entry<K,V> result = exportEntry(e); 1581 if (e != null) 1582 m.deleteEntry(e); 1583 return result; 1584 } 1585 1586 public final Map.Entry<K,V> pollLastEntry() { 1587 TreeMapEntry<K,V> e = subHighest(); 1588 Map.Entry<K,V> result = exportEntry(e); 1589 if (e != null) 1590 m.deleteEntry(e); 1591 return result; 1592 } 1593 1594 // Views 1595 transient NavigableMap<K,V> descendingMapView = null; 1596 transient EntrySetView entrySetView = null; 1597 transient KeySet<K> navigableKeySetView = null; 1598 1599 public final NavigableSet<K> navigableKeySet() { 1600 KeySet<K> nksv = navigableKeySetView; 1601 return (nksv != null) ? nksv : 1602 (navigableKeySetView = new TreeMap.KeySet<>(this)); 1603 } 1604 1605 public final Set<K> keySet() { 1606 return navigableKeySet(); 1607 } 1608 1609 public NavigableSet<K> descendingKeySet() { 1610 return descendingMap().navigableKeySet(); 1611 } 1612 1613 public final SortedMap<K,V> subMap(K fromKey, K toKey) { 1614 return subMap(fromKey, true, toKey, false); 1615 } 1616 1617 public final SortedMap<K,V> headMap(K toKey) { 1618 return headMap(toKey, false); 1619 } 1620 1621 public final SortedMap<K,V> tailMap(K fromKey) { 1622 return tailMap(fromKey, true); 1623 } 1624 1625 // View classes 1626 1627 abstract class EntrySetView extends AbstractSet<Map.Entry<K,V>> { 1628 private transient int size = -1, sizeModCount; 1629 1630 public int size() { 1631 if (fromStart && toEnd) 1632 return m.size(); 1633 if (size == -1 || sizeModCount != m.modCount) { 1634 sizeModCount = m.modCount; 1635 size = 0; 1636 Iterator<?> i = iterator(); 1637 while (i.hasNext()) { 1638 size++; 1639 i.next(); 1640 } 1641 } 1642 return size; 1643 } 1644 1645 public boolean isEmpty() { 1646 TreeMapEntry<K,V> n = absLowest(); 1647 return n == null || tooHigh(n.key); 1648 } 1649 1650 public boolean contains(Object o) { 1651 if (!(o instanceof Map.Entry)) 1652 return false; 1653 Map.Entry<?,?> entry = (Map.Entry<?,?>) o; 1654 Object key = entry.getKey(); 1655 if (!inRange(key)) 1656 return false; 1657 TreeMapEntry<?, ?> node = m.getEntry(key); 1658 return node != null && 1659 valEquals(node.getValue(), entry.getValue()); 1660 } 1661 1662 public boolean remove(Object o) { 1663 if (!(o instanceof Map.Entry)) 1664 return false; 1665 Map.Entry<?,?> entry = (Map.Entry<?,?>) o; 1666 Object key = entry.getKey(); 1667 if (!inRange(key)) 1668 return false; 1669 TreeMapEntry<K,V> node = m.getEntry(key); 1670 if (node!=null && valEquals(node.getValue(), 1671 entry.getValue())) { 1672 m.deleteEntry(node); 1673 return true; 1674 } 1675 return false; 1676 } 1677 } 1678 1679 /** 1680 * Iterators for SubMaps 1681 */ 1682 abstract class SubMapIterator<T> implements Iterator<T> { 1683 TreeMapEntry<K,V> lastReturned; 1684 TreeMapEntry<K,V> next; 1685 final Object fenceKey; 1686 int expectedModCount; 1687 1688 SubMapIterator(TreeMapEntry<K,V> first, 1689 TreeMapEntry<K,V> fence) { 1690 expectedModCount = m.modCount; 1691 lastReturned = null; 1692 next = first; 1693 fenceKey = fence == null ? UNBOUNDED : fence.key; 1694 } 1695 1696 public final boolean hasNext() { 1697 return next != null && next.key != fenceKey; 1698 } 1699 1700 final TreeMapEntry<K,V> nextEntry() { 1701 TreeMapEntry<K,V> e = next; 1702 if (e == null || e.key == fenceKey) 1703 throw new NoSuchElementException(); 1704 if (m.modCount != expectedModCount) 1705 throw new ConcurrentModificationException(); 1706 next = successor(e); 1707 lastReturned = e; 1708 return e; 1709 } 1710 1711 final TreeMapEntry<K,V> prevEntry() { 1712 TreeMapEntry<K,V> e = next; 1713 if (e == null || e.key == fenceKey) 1714 throw new NoSuchElementException(); 1715 if (m.modCount != expectedModCount) 1716 throw new ConcurrentModificationException(); 1717 next = predecessor(e); 1718 lastReturned = e; 1719 return e; 1720 } 1721 1722 final void removeAscending() { 1723 if (lastReturned == null) 1724 throw new IllegalStateException(); 1725 if (m.modCount != expectedModCount) 1726 throw new ConcurrentModificationException(); 1727 // deleted entries are replaced by their successors 1728 if (lastReturned.left != null && lastReturned.right != null) 1729 next = lastReturned; 1730 m.deleteEntry(lastReturned); 1731 lastReturned = null; 1732 expectedModCount = m.modCount; 1733 } 1734 1735 final void removeDescending() { 1736 if (lastReturned == null) 1737 throw new IllegalStateException(); 1738 if (m.modCount != expectedModCount) 1739 throw new ConcurrentModificationException(); 1740 m.deleteEntry(lastReturned); 1741 lastReturned = null; 1742 expectedModCount = m.modCount; 1743 } 1744 1745 } 1746 1747 final class SubMapEntryIterator extends SubMapIterator<Map.Entry<K,V>> { 1748 SubMapEntryIterator(TreeMapEntry<K,V> first, 1749 TreeMapEntry<K,V> fence) { 1750 super(first, fence); 1751 } 1752 public Map.Entry<K,V> next() { 1753 return nextEntry(); 1754 } 1755 public void remove() { 1756 removeAscending(); 1757 } 1758 } 1759 1760 final class DescendingSubMapEntryIterator extends SubMapIterator<Map.Entry<K,V>> { 1761 DescendingSubMapEntryIterator(TreeMapEntry<K,V> last, 1762 TreeMapEntry<K,V> fence) { 1763 super(last, fence); 1764 } 1765 1766 public Map.Entry<K,V> next() { 1767 return prevEntry(); 1768 } 1769 public void remove() { 1770 removeDescending(); 1771 } 1772 } 1773 1774 // Implement minimal Spliterator as KeySpliterator backup 1775 final class SubMapKeyIterator extends SubMapIterator<K> 1776 implements Spliterator<K> { 1777 SubMapKeyIterator(TreeMapEntry<K,V> first, 1778 TreeMapEntry<K,V> fence) { 1779 super(first, fence); 1780 } 1781 public K next() { 1782 return nextEntry().key; 1783 } 1784 public void remove() { 1785 removeAscending(); 1786 } 1787 public Spliterator<K> trySplit() { 1788 return null; 1789 } 1790 public void forEachRemaining(Consumer<? super K> action) { 1791 while (hasNext()) 1792 action.accept(next()); 1793 } 1794 public boolean tryAdvance(Consumer<? super K> action) { 1795 if (hasNext()) { 1796 action.accept(next()); 1797 return true; 1798 } 1799 return false; 1800 } 1801 public long estimateSize() { 1802 return Long.MAX_VALUE; 1803 } 1804 public int characteristics() { 1805 return Spliterator.DISTINCT | Spliterator.ORDERED | 1806 Spliterator.SORTED; 1807 } 1808 public final Comparator<? super K> getComparator() { 1809 return NavigableSubMap.this.comparator(); 1810 } 1811 } 1812 1813 final class DescendingSubMapKeyIterator extends SubMapIterator<K> 1814 implements Spliterator<K> { 1815 DescendingSubMapKeyIterator(TreeMapEntry<K,V> last, 1816 TreeMapEntry<K,V> fence) { 1817 super(last, fence); 1818 } 1819 public K next() { 1820 return prevEntry().key; 1821 } 1822 public void remove() { 1823 removeDescending(); 1824 } 1825 public Spliterator<K> trySplit() { 1826 return null; 1827 } 1828 public void forEachRemaining(Consumer<? super K> action) { 1829 while (hasNext()) 1830 action.accept(next()); 1831 } 1832 public boolean tryAdvance(Consumer<? super K> action) { 1833 if (hasNext()) { 1834 action.accept(next()); 1835 return true; 1836 } 1837 return false; 1838 } 1839 public long estimateSize() { 1840 return Long.MAX_VALUE; 1841 } 1842 public int characteristics() { 1843 return Spliterator.DISTINCT | Spliterator.ORDERED; 1844 } 1845 } 1846 } 1847 1848 /** 1849 * @serial include 1850 */ 1851 static final class AscendingSubMap<K,V> extends NavigableSubMap<K,V> { 1852 private static final long serialVersionUID = 912986545866124060L; 1853 1854 AscendingSubMap(TreeMap<K,V> m, 1855 boolean fromStart, K lo, boolean loInclusive, 1856 boolean toEnd, K hi, boolean hiInclusive) { 1857 super(m, fromStart, lo, loInclusive, toEnd, hi, hiInclusive); 1858 } 1859 1860 public Comparator<? super K> comparator() { 1861 return m.comparator(); 1862 } 1863 1864 public NavigableMap<K,V> subMap(K fromKey, boolean fromInclusive, 1865 K toKey, boolean toInclusive) { 1866 if (!inRange(fromKey, fromInclusive)) 1867 throw new IllegalArgumentException("fromKey out of range"); 1868 if (!inRange(toKey, toInclusive)) 1869 throw new IllegalArgumentException("toKey out of range"); 1870 return new AscendingSubMap<>(m, 1871 false, fromKey, fromInclusive, 1872 false, toKey, toInclusive); 1873 } 1874 1875 public NavigableMap<K,V> headMap(K toKey, boolean inclusive) { 1876 /* ----- BEGIN android ----- 1877 Fix for edge cases 1878 if (!inRange(toKey, inclusive)) */ 1879 if (!inRange(toKey) && !(!toEnd && m.compare(toKey, hi) == 0 && 1880 !hiInclusive && !inclusive)) 1881 // ----- END android ----- 1882 throw new IllegalArgumentException("toKey out of range"); 1883 return new AscendingSubMap<>(m, 1884 fromStart, lo, loInclusive, 1885 false, toKey, inclusive); 1886 } 1887 1888 public NavigableMap<K,V> tailMap(K fromKey, boolean inclusive) { 1889 /* ----- BEGIN android ----- 1890 Fix for edge cases 1891 if (!inRange(fromKey, inclusive)) */ 1892 if (!inRange(fromKey) && !(!fromStart && m.compare(fromKey, lo) == 0 && 1893 !loInclusive && !inclusive)) 1894 // ----- END android ----- 1895 throw new IllegalArgumentException("fromKey out of range"); 1896 return new AscendingSubMap<>(m, 1897 false, fromKey, inclusive, 1898 toEnd, hi, hiInclusive); 1899 } 1900 1901 public NavigableMap<K,V> descendingMap() { 1902 NavigableMap<K,V> mv = descendingMapView; 1903 return (mv != null) ? mv : 1904 (descendingMapView = 1905 new DescendingSubMap<>(m, 1906 fromStart, lo, loInclusive, 1907 toEnd, hi, hiInclusive)); 1908 } 1909 1910 Iterator<K> keyIterator() { 1911 return new SubMapKeyIterator(absLowest(), absHighFence()); 1912 } 1913 1914 Spliterator<K> keySpliterator() { 1915 return new SubMapKeyIterator(absLowest(), absHighFence()); 1916 } 1917 1918 Iterator<K> descendingKeyIterator() { 1919 return new DescendingSubMapKeyIterator(absHighest(), absLowFence()); 1920 } 1921 1922 final class AscendingEntrySetView extends EntrySetView { 1923 public Iterator<Map.Entry<K,V>> iterator() { 1924 return new SubMapEntryIterator(absLowest(), absHighFence()); 1925 } 1926 } 1927 1928 public Set<Map.Entry<K,V>> entrySet() { 1929 EntrySetView es = entrySetView; 1930 return (es != null) ? es : new AscendingEntrySetView(); 1931 } 1932 1933 TreeMapEntry<K,V> subLowest() { return absLowest(); } 1934 TreeMapEntry<K,V> subHighest() { return absHighest(); } 1935 TreeMapEntry<K,V> subCeiling(K key) { return absCeiling(key); } 1936 TreeMapEntry<K,V> subHigher(K key) { return absHigher(key); } 1937 TreeMapEntry<K,V> subFloor(K key) { return absFloor(key); } 1938 TreeMapEntry<K,V> subLower(K key) { return absLower(key); } 1939 } 1940 1941 /** 1942 * @serial include 1943 */ 1944 static final class DescendingSubMap<K,V> extends NavigableSubMap<K,V> { 1945 private static final long serialVersionUID = 912986545866120460L; 1946 DescendingSubMap(TreeMap<K,V> m, 1947 boolean fromStart, K lo, boolean loInclusive, 1948 boolean toEnd, K hi, boolean hiInclusive) { 1949 super(m, fromStart, lo, loInclusive, toEnd, hi, hiInclusive); 1950 } 1951 1952 private final Comparator<? super K> reverseComparator = 1953 Collections.reverseOrder(m.comparator); 1954 1955 public Comparator<? super K> comparator() { 1956 return reverseComparator; 1957 } 1958 1959 public NavigableMap<K,V> subMap(K fromKey, boolean fromInclusive, 1960 K toKey, boolean toInclusive) { 1961 if (!inRange(fromKey, fromInclusive)) 1962 throw new IllegalArgumentException("fromKey out of range"); 1963 if (!inRange(toKey, toInclusive)) 1964 throw new IllegalArgumentException("toKey out of range"); 1965 return new DescendingSubMap<>(m, 1966 false, toKey, toInclusive, 1967 false, fromKey, fromInclusive); 1968 } 1969 1970 public NavigableMap<K,V> headMap(K toKey, boolean inclusive) { 1971 /* ----- BEGIN android ----- 1972 Fix for edge cases 1973 if (!inRange(toKey, inclusive)) */ 1974 if (!inRange(toKey) && !(!fromStart && m.compare(toKey, lo) == 0 && 1975 !loInclusive && !inclusive)) 1976 // ----- END android ----- 1977 throw new IllegalArgumentException("toKey out of range"); 1978 return new DescendingSubMap<>(m, 1979 false, toKey, inclusive, 1980 toEnd, hi, hiInclusive); 1981 } 1982 1983 public NavigableMap<K,V> tailMap(K fromKey, boolean inclusive) { 1984 /* ----- BEGIN android ----- 1985 Fix for edge cases 1986 if (!inRange(fromKey, inclusive)) */ 1987 if (!inRange(fromKey) && !(!toEnd && m.compare(fromKey, hi) == 0 && 1988 !hiInclusive && !inclusive)) 1989 // ----- END android ----- 1990 throw new IllegalArgumentException("fromKey out of range"); 1991 return new DescendingSubMap<>(m, 1992 fromStart, lo, loInclusive, 1993 false, fromKey, inclusive); 1994 } 1995 1996 public NavigableMap<K,V> descendingMap() { 1997 NavigableMap<K,V> mv = descendingMapView; 1998 return (mv != null) ? mv : 1999 (descendingMapView = 2000 new AscendingSubMap<>(m, 2001 fromStart, lo, loInclusive, 2002 toEnd, hi, hiInclusive)); 2003 } 2004 2005 Iterator<K> keyIterator() { 2006 return new DescendingSubMapKeyIterator(absHighest(), absLowFence()); 2007 } 2008 2009 Spliterator<K> keySpliterator() { 2010 return new DescendingSubMapKeyIterator(absHighest(), absLowFence()); 2011 } 2012 2013 Iterator<K> descendingKeyIterator() { 2014 return new SubMapKeyIterator(absLowest(), absHighFence()); 2015 } 2016 2017 final class DescendingEntrySetView extends EntrySetView { 2018 public Iterator<Map.Entry<K,V>> iterator() { 2019 return new DescendingSubMapEntryIterator(absHighest(), absLowFence()); 2020 } 2021 } 2022 2023 public Set<Map.Entry<K,V>> entrySet() { 2024 EntrySetView es = entrySetView; 2025 return (es != null) ? es : (entrySetView = new DescendingEntrySetView()); 2026 } 2027 2028 TreeMapEntry<K,V> subLowest() { return absHighest(); } 2029 TreeMapEntry<K,V> subHighest() { return absLowest(); } 2030 TreeMapEntry<K,V> subCeiling(K key) { return absFloor(key); } 2031 TreeMapEntry<K,V> subHigher(K key) { return absLower(key); } 2032 TreeMapEntry<K,V> subFloor(K key) { return absCeiling(key); } 2033 TreeMapEntry<K,V> subLower(K key) { return absHigher(key); } 2034 } 2035 2036 /** 2037 * This class exists solely for the sake of serialization 2038 * compatibility with previous releases of TreeMap that did not 2039 * support NavigableMap. It translates an old-version SubMap into 2040 * a new-version AscendingSubMap. This class is never otherwise 2041 * used. 2042 * 2043 * @serial include 2044 */ 2045 private class SubMap extends AbstractMap<K,V> 2046 implements SortedMap<K,V>, java.io.Serializable { 2047 private static final long serialVersionUID = -6520786458950516097L; 2048 private boolean fromStart = false, toEnd = false; 2049 private K fromKey, toKey; 2050 private Object readResolve() { 2051 return new AscendingSubMap<>(TreeMap.this, 2052 fromStart, fromKey, true, 2053 toEnd, toKey, false); 2054 } 2055 public Set<Map.Entry<K,V>> entrySet() { throw new InternalError(); } 2056 public K lastKey() { throw new InternalError(); } 2057 public K firstKey() { throw new InternalError(); } 2058 public SortedMap<K,V> subMap(K fromKey, K toKey) { throw new InternalError(); } 2059 public SortedMap<K,V> headMap(K toKey) { throw new InternalError(); } 2060 public SortedMap<K,V> tailMap(K fromKey) { throw new InternalError(); } 2061 public Comparator<? super K> comparator() { throw new InternalError(); } 2062 } 2063 2064 2065 // Red-black mechanics 2066 2067 private static final boolean RED = false; 2068 private static final boolean BLACK = true; 2069 2070 /** 2071 * Node in the Tree. Doubles as a means to pass key-value pairs back to 2072 * user (see Map.Entry). 2073 */ 2074 2075 static final class TreeMapEntry<K,V> implements Map.Entry<K,V> { 2076 K key; 2077 V value; 2078 TreeMapEntry<K,V> left = null; 2079 TreeMapEntry<K,V> right = null; 2080 TreeMapEntry<K,V> parent; 2081 boolean color = BLACK; 2082 2083 /** 2084 * Make a new cell with given key, value, and parent, and with 2085 * {@code null} child links, and BLACK color. 2086 */ 2087 TreeMapEntry(K key, V value, TreeMapEntry<K,V> parent) { 2088 this.key = key; 2089 this.value = value; 2090 this.parent = parent; 2091 } 2092 2093 /** 2094 * Returns the key. 2095 * 2096 * @return the key 2097 */ 2098 public K getKey() { 2099 return key; 2100 } 2101 2102 /** 2103 * Returns the value associated with the key. 2104 * 2105 * @return the value associated with the key 2106 */ 2107 public V getValue() { 2108 return value; 2109 } 2110 2111 /** 2112 * Replaces the value currently associated with the key with the given 2113 * value. 2114 * 2115 * @return the value associated with the key before this method was 2116 * called 2117 */ 2118 public V setValue(V value) { 2119 V oldValue = this.value; 2120 this.value = value; 2121 return oldValue; 2122 } 2123 2124 public boolean equals(Object o) { 2125 if (!(o instanceof Map.Entry)) 2126 return false; 2127 Map.Entry<?,?> e = (Map.Entry<?,?>)o; 2128 2129 return valEquals(key,e.getKey()) && valEquals(value,e.getValue()); 2130 } 2131 2132 public int hashCode() { 2133 int keyHash = (key==null ? 0 : key.hashCode()); 2134 int valueHash = (value==null ? 0 : value.hashCode()); 2135 return keyHash ^ valueHash; 2136 } 2137 2138 public String toString() { 2139 return key + "=" + value; 2140 } 2141 } 2142 2143 /** 2144 * Returns the first Entry in the TreeMap (according to the TreeMap's 2145 * key-sort function). Returns null if the TreeMap is empty. 2146 */ 2147 final TreeMapEntry<K,V> getFirstEntry() { 2148 TreeMapEntry<K,V> p = root; 2149 if (p != null) 2150 while (p.left != null) 2151 p = p.left; 2152 return p; 2153 } 2154 2155 /** 2156 * Returns the last Entry in the TreeMap (according to the TreeMap's 2157 * key-sort function). Returns null if the TreeMap is empty. 2158 */ 2159 final TreeMapEntry<K,V> getLastEntry() { 2160 TreeMapEntry<K,V> p = root; 2161 if (p != null) 2162 while (p.right != null) 2163 p = p.right; 2164 return p; 2165 } 2166 2167 /** 2168 * Returns the successor of the specified Entry, or null if no such. 2169 */ 2170 static <K,V> TreeMapEntry<K,V> successor(TreeMapEntry<K,V> t) { 2171 if (t == null) 2172 return null; 2173 else if (t.right != null) { 2174 TreeMapEntry<K,V> p = t.right; 2175 while (p.left != null) 2176 p = p.left; 2177 return p; 2178 } else { 2179 TreeMapEntry<K,V> p = t.parent; 2180 TreeMapEntry<K,V> ch = t; 2181 while (p != null && ch == p.right) { 2182 ch = p; 2183 p = p.parent; 2184 } 2185 return p; 2186 } 2187 } 2188 2189 /** 2190 * Returns the predecessor of the specified Entry, or null if no such. 2191 */ 2192 static <K,V> TreeMapEntry<K,V> predecessor(TreeMapEntry<K,V> t) { 2193 if (t == null) 2194 return null; 2195 else if (t.left != null) { 2196 TreeMapEntry<K,V> p = t.left; 2197 while (p.right != null) 2198 p = p.right; 2199 return p; 2200 } else { 2201 TreeMapEntry<K,V> p = t.parent; 2202 TreeMapEntry<K,V> ch = t; 2203 while (p != null && ch == p.left) { 2204 ch = p; 2205 p = p.parent; 2206 } 2207 return p; 2208 } 2209 } 2210 2211 /** 2212 * Balancing operations. 2213 * 2214 * Implementations of rebalancings during insertion and deletion are 2215 * slightly different than the CLR version. Rather than using dummy 2216 * nilnodes, we use a set of accessors that deal properly with null. They 2217 * are used to avoid messiness surrounding nullness checks in the main 2218 * algorithms. 2219 */ 2220 2221 private static <K,V> boolean colorOf(TreeMapEntry<K,V> p) { 2222 return (p == null ? BLACK : p.color); 2223 } 2224 2225 private static <K,V> TreeMapEntry<K,V> parentOf(TreeMapEntry<K,V> p) { 2226 return (p == null ? null: p.parent); 2227 } 2228 2229 private static <K,V> void setColor(TreeMapEntry<K,V> p, boolean c) { 2230 if (p != null) 2231 p.color = c; 2232 } 2233 2234 private static <K,V> TreeMapEntry<K,V> leftOf(TreeMapEntry<K,V> p) { 2235 return (p == null) ? null: p.left; 2236 } 2237 2238 private static <K,V> TreeMapEntry<K,V> rightOf(TreeMapEntry<K,V> p) { 2239 return (p == null) ? null: p.right; 2240 } 2241 2242 /** From CLR */ 2243 private void rotateLeft(TreeMapEntry<K,V> p) { 2244 if (p != null) { 2245 TreeMapEntry<K,V> r = p.right; 2246 p.right = r.left; 2247 if (r.left != null) 2248 r.left.parent = p; 2249 r.parent = p.parent; 2250 if (p.parent == null) 2251 root = r; 2252 else if (p.parent.left == p) 2253 p.parent.left = r; 2254 else 2255 p.parent.right = r; 2256 r.left = p; 2257 p.parent = r; 2258 } 2259 } 2260 2261 /** From CLR */ 2262 private void rotateRight(TreeMapEntry<K,V> p) { 2263 if (p != null) { 2264 TreeMapEntry<K,V> l = p.left; 2265 p.left = l.right; 2266 if (l.right != null) l.right.parent = p; 2267 l.parent = p.parent; 2268 if (p.parent == null) 2269 root = l; 2270 else if (p.parent.right == p) 2271 p.parent.right = l; 2272 else p.parent.left = l; 2273 l.right = p; 2274 p.parent = l; 2275 } 2276 } 2277 2278 /** From CLR */ 2279 private void fixAfterInsertion(TreeMapEntry<K,V> x) { 2280 x.color = RED; 2281 2282 while (x != null && x != root && x.parent.color == RED) { 2283 if (parentOf(x) == leftOf(parentOf(parentOf(x)))) { 2284 TreeMapEntry<K,V> y = rightOf(parentOf(parentOf(x))); 2285 if (colorOf(y) == RED) { 2286 setColor(parentOf(x), BLACK); 2287 setColor(y, BLACK); 2288 setColor(parentOf(parentOf(x)), RED); 2289 x = parentOf(parentOf(x)); 2290 } else { 2291 if (x == rightOf(parentOf(x))) { 2292 x = parentOf(x); 2293 rotateLeft(x); 2294 } 2295 setColor(parentOf(x), BLACK); 2296 setColor(parentOf(parentOf(x)), RED); 2297 rotateRight(parentOf(parentOf(x))); 2298 } 2299 } else { 2300 TreeMapEntry<K,V> y = leftOf(parentOf(parentOf(x))); 2301 if (colorOf(y) == RED) { 2302 setColor(parentOf(x), BLACK); 2303 setColor(y, BLACK); 2304 setColor(parentOf(parentOf(x)), RED); 2305 x = parentOf(parentOf(x)); 2306 } else { 2307 if (x == leftOf(parentOf(x))) { 2308 x = parentOf(x); 2309 rotateRight(x); 2310 } 2311 setColor(parentOf(x), BLACK); 2312 setColor(parentOf(parentOf(x)), RED); 2313 rotateLeft(parentOf(parentOf(x))); 2314 } 2315 } 2316 } 2317 root.color = BLACK; 2318 } 2319 2320 /** 2321 * Delete node p, and then rebalance the tree. 2322 */ 2323 private void deleteEntry(TreeMapEntry<K,V> p) { 2324 modCount++; 2325 size--; 2326 2327 // If strictly internal, copy successor's element to p and then make p 2328 // point to successor. 2329 if (p.left != null && p.right != null) { 2330 TreeMapEntry<K,V> s = successor(p); 2331 p.key = s.key; 2332 p.value = s.value; 2333 p = s; 2334 } // p has 2 children 2335 2336 // Start fixup at replacement node, if it exists. 2337 TreeMapEntry<K,V> replacement = (p.left != null ? p.left : p.right); 2338 2339 if (replacement != null) { 2340 // Link replacement to parent 2341 replacement.parent = p.parent; 2342 if (p.parent == null) 2343 root = replacement; 2344 else if (p == p.parent.left) 2345 p.parent.left = replacement; 2346 else 2347 p.parent.right = replacement; 2348 2349 // Null out links so they are OK to use by fixAfterDeletion. 2350 p.left = p.right = p.parent = null; 2351 2352 // Fix replacement 2353 if (p.color == BLACK) 2354 fixAfterDeletion(replacement); 2355 } else if (p.parent == null) { // return if we are the only node. 2356 root = null; 2357 } else { // No children. Use self as phantom replacement and unlink. 2358 if (p.color == BLACK) 2359 fixAfterDeletion(p); 2360 2361 if (p.parent != null) { 2362 if (p == p.parent.left) 2363 p.parent.left = null; 2364 else if (p == p.parent.right) 2365 p.parent.right = null; 2366 p.parent = null; 2367 } 2368 } 2369 } 2370 2371 /** From CLR */ 2372 private void fixAfterDeletion(TreeMapEntry<K,V> x) { 2373 while (x != root && colorOf(x) == BLACK) { 2374 if (x == leftOf(parentOf(x))) { 2375 TreeMapEntry<K,V> sib = rightOf(parentOf(x)); 2376 2377 if (colorOf(sib) == RED) { 2378 setColor(sib, BLACK); 2379 setColor(parentOf(x), RED); 2380 rotateLeft(parentOf(x)); 2381 sib = rightOf(parentOf(x)); 2382 } 2383 2384 if (colorOf(leftOf(sib)) == BLACK && 2385 colorOf(rightOf(sib)) == BLACK) { 2386 setColor(sib, RED); 2387 x = parentOf(x); 2388 } else { 2389 if (colorOf(rightOf(sib)) == BLACK) { 2390 setColor(leftOf(sib), BLACK); 2391 setColor(sib, RED); 2392 rotateRight(sib); 2393 sib = rightOf(parentOf(x)); 2394 } 2395 setColor(sib, colorOf(parentOf(x))); 2396 setColor(parentOf(x), BLACK); 2397 setColor(rightOf(sib), BLACK); 2398 rotateLeft(parentOf(x)); 2399 x = root; 2400 } 2401 } else { // symmetric 2402 TreeMapEntry<K,V> sib = leftOf(parentOf(x)); 2403 2404 if (colorOf(sib) == RED) { 2405 setColor(sib, BLACK); 2406 setColor(parentOf(x), RED); 2407 rotateRight(parentOf(x)); 2408 sib = leftOf(parentOf(x)); 2409 } 2410 2411 if (colorOf(rightOf(sib)) == BLACK && 2412 colorOf(leftOf(sib)) == BLACK) { 2413 setColor(sib, RED); 2414 x = parentOf(x); 2415 } else { 2416 if (colorOf(leftOf(sib)) == BLACK) { 2417 setColor(rightOf(sib), BLACK); 2418 setColor(sib, RED); 2419 rotateLeft(sib); 2420 sib = leftOf(parentOf(x)); 2421 } 2422 setColor(sib, colorOf(parentOf(x))); 2423 setColor(parentOf(x), BLACK); 2424 setColor(leftOf(sib), BLACK); 2425 rotateRight(parentOf(x)); 2426 x = root; 2427 } 2428 } 2429 } 2430 2431 setColor(x, BLACK); 2432 } 2433 2434 private static final long serialVersionUID = 919286545866124006L; 2435 2436 /** 2437 * Save the state of the {@code TreeMap} instance to a stream (i.e., 2438 * serialize it). 2439 * 2440 * @serialData The <em>size</em> of the TreeMap (the number of key-value 2441 * mappings) is emitted (int), followed by the key (Object) 2442 * and value (Object) for each key-value mapping represented 2443 * by the TreeMap. The key-value mappings are emitted in 2444 * key-order (as determined by the TreeMap's Comparator, 2445 * or by the keys' natural ordering if the TreeMap has no 2446 * Comparator). 2447 */ 2448 private void writeObject(java.io.ObjectOutputStream s) 2449 throws java.io.IOException { 2450 // Write out the Comparator and any hidden stuff 2451 s.defaultWriteObject(); 2452 2453 // Write out size (number of Mappings) 2454 s.writeInt(size); 2455 2456 // Write out keys and values (alternating) 2457 for (Iterator<Map.Entry<K,V>> i = entrySet().iterator(); i.hasNext(); ) { 2458 Map.Entry<K,V> e = i.next(); 2459 s.writeObject(e.getKey()); 2460 s.writeObject(e.getValue()); 2461 } 2462 } 2463 2464 /** 2465 * Reconstitute the {@code TreeMap} instance from a stream (i.e., 2466 * deserialize it). 2467 */ 2468 private void readObject(final java.io.ObjectInputStream s) 2469 throws java.io.IOException, ClassNotFoundException { 2470 // Read in the Comparator and any hidden stuff 2471 s.defaultReadObject(); 2472 2473 // Read in size 2474 int size = s.readInt(); 2475 2476 buildFromSorted(size, null, s, null); 2477 } 2478 2479 /** Intended to be called only from TreeSet.readObject */ 2480 void readTreeSet(int size, java.io.ObjectInputStream s, V defaultVal) 2481 throws java.io.IOException, ClassNotFoundException { 2482 buildFromSorted(size, null, s, defaultVal); 2483 } 2484 2485 /** Intended to be called only from TreeSet.addAll */ 2486 void addAllForTreeSet(SortedSet<? extends K> set, V defaultVal) { 2487 try { 2488 buildFromSorted(set.size(), set.iterator(), null, defaultVal); 2489 } catch (java.io.IOException cannotHappen) { 2490 } catch (ClassNotFoundException cannotHappen) { 2491 } 2492 } 2493 2494 2495 /** 2496 * Linear time tree building algorithm from sorted data. Can accept keys 2497 * and/or values from iterator or stream. This leads to too many 2498 * parameters, but seems better than alternatives. The four formats 2499 * that this method accepts are: 2500 * 2501 * 1) An iterator of Map.Entries. (it != null, defaultVal == null). 2502 * 2) An iterator of keys. (it != null, defaultVal != null). 2503 * 3) A stream of alternating serialized keys and values. 2504 * (it == null, defaultVal == null). 2505 * 4) A stream of serialized keys. (it == null, defaultVal != null). 2506 * 2507 * It is assumed that the comparator of the TreeMap is already set prior 2508 * to calling this method. 2509 * 2510 * @param size the number of keys (or key-value pairs) to be read from 2511 * the iterator or stream 2512 * @param it If non-null, new entries are created from entries 2513 * or keys read from this iterator. 2514 * @param str If non-null, new entries are created from keys and 2515 * possibly values read from this stream in serialized form. 2516 * Exactly one of it and str should be non-null. 2517 * @param defaultVal if non-null, this default value is used for 2518 * each value in the map. If null, each value is read from 2519 * iterator or stream, as described above. 2520 * @throws java.io.IOException propagated from stream reads. This cannot 2521 * occur if str is null. 2522 * @throws ClassNotFoundException propagated from readObject. 2523 * This cannot occur if str is null. 2524 */ 2525 private void buildFromSorted(int size, Iterator<?> it, 2526 java.io.ObjectInputStream str, 2527 V defaultVal) 2528 throws java.io.IOException, ClassNotFoundException { 2529 this.size = size; 2530 root = buildFromSorted(0, 0, size-1, computeRedLevel(size), 2531 it, str, defaultVal); 2532 } 2533 2534 /** 2535 * Recursive "helper method" that does the real work of the 2536 * previous method. Identically named parameters have 2537 * identical definitions. Additional parameters are documented below. 2538 * It is assumed that the comparator and size fields of the TreeMap are 2539 * already set prior to calling this method. (It ignores both fields.) 2540 * 2541 * @param level the current level of tree. Initial call should be 0. 2542 * @param lo the first element index of this subtree. Initial should be 0. 2543 * @param hi the last element index of this subtree. Initial should be 2544 * size-1. 2545 * @param redLevel the level at which nodes should be red. 2546 * Must be equal to computeRedLevel for tree of this size. 2547 */ 2548 @SuppressWarnings("unchecked") 2549 private final TreeMapEntry<K,V> buildFromSorted(int level, int lo, int hi, 2550 int redLevel, 2551 Iterator<?> it, 2552 java.io.ObjectInputStream str, 2553 V defaultVal) 2554 throws java.io.IOException, ClassNotFoundException { 2555 /* 2556 * Strategy: The root is the middlemost element. To get to it, we 2557 * have to first recursively construct the entire left subtree, 2558 * so as to grab all of its elements. We can then proceed with right 2559 * subtree. 2560 * 2561 * The lo and hi arguments are the minimum and maximum 2562 * indices to pull out of the iterator or stream for current subtree. 2563 * They are not actually indexed, we just proceed sequentially, 2564 * ensuring that items are extracted in corresponding order. 2565 */ 2566 2567 if (hi < lo) return null; 2568 2569 int mid = (lo + hi) >>> 1; 2570 2571 TreeMapEntry<K,V> left = null; 2572 if (lo < mid) 2573 left = buildFromSorted(level+1, lo, mid - 1, redLevel, 2574 it, str, defaultVal); 2575 2576 // extract key and/or value from iterator or stream 2577 K key; 2578 V value; 2579 if (it != null) { 2580 if (defaultVal==null) { 2581 Map.Entry<K,V> entry = (Map.Entry<K,V>)it.next(); 2582 key = entry.getKey(); 2583 value = entry.getValue(); 2584 } else { 2585 key = (K)it.next(); 2586 value = defaultVal; 2587 } 2588 } else { // use stream 2589 key = (K) str.readObject(); 2590 value = (defaultVal != null ? defaultVal : (V) str.readObject()); 2591 } 2592 2593 TreeMapEntry<K,V> middle = new TreeMapEntry<>(key, value, null); 2594 2595 // color nodes in non-full bottommost level red 2596 if (level == redLevel) 2597 middle.color = RED; 2598 2599 if (left != null) { 2600 middle.left = left; 2601 left.parent = middle; 2602 } 2603 2604 if (mid < hi) { 2605 TreeMapEntry<K,V> right = buildFromSorted(level+1, mid+1, hi, redLevel, 2606 it, str, defaultVal); 2607 middle.right = right; 2608 right.parent = middle; 2609 } 2610 2611 return middle; 2612 } 2613 2614 /** 2615 * Find the level down to which to assign all nodes BLACK. This is the 2616 * last `full' level of the complete binary tree produced by 2617 * buildTree. The remaining nodes are colored RED. (This makes a `nice' 2618 * set of color assignments wrt future insertions.) This level number is 2619 * computed by finding the number of splits needed to reach the zeroeth 2620 * node. (The answer is ~lg(N), but in any case must be computed by same 2621 * quick O(lg(N)) loop.) 2622 */ 2623 private static int computeRedLevel(int sz) { 2624 int level = 0; 2625 for (int m = sz - 1; m >= 0; m = m / 2 - 1) 2626 level++; 2627 return level; 2628 } 2629 2630 /** 2631 * Currently, we support Spliterator-based versions only for the 2632 * full map, in either plain of descending form, otherwise relying 2633 * on defaults because size estimation for submaps would dominate 2634 * costs. The type tests needed to check these for key views are 2635 * not very nice but avoid disrupting existing class 2636 * structures. Callers must use plain default spliterators if this 2637 * returns null. 2638 */ 2639 static <K> Spliterator<K> keySpliteratorFor(NavigableMap<K,?> m) { 2640 if (m instanceof TreeMap) { 2641 @SuppressWarnings("unchecked") TreeMap<K,Object> t = 2642 (TreeMap<K,Object>) m; 2643 return t.keySpliterator(); 2644 } 2645 if (m instanceof DescendingSubMap) { 2646 @SuppressWarnings("unchecked") DescendingSubMap<K,?> dm = 2647 (DescendingSubMap<K,?>) m; 2648 TreeMap<K,?> tm = dm.m; 2649 if (dm == tm.descendingMap) { 2650 @SuppressWarnings("unchecked") TreeMap<K,Object> t = 2651 (TreeMap<K,Object>) tm; 2652 return t.descendingKeySpliterator(); 2653 } 2654 } 2655 @SuppressWarnings("unchecked") NavigableSubMap<K,?> sm = 2656 (NavigableSubMap<K,?>) m; 2657 return sm.keySpliterator(); 2658 } 2659 2660 final Spliterator<K> keySpliterator() { 2661 return new KeySpliterator<K,V>(this, null, null, 0, -1, 0); 2662 } 2663 2664 final Spliterator<K> descendingKeySpliterator() { 2665 return new DescendingKeySpliterator<K,V>(this, null, null, 0, -2, 0); 2666 } 2667 2668 /** 2669 * Base class for spliterators. Iteration starts at a given 2670 * origin and continues up to but not including a given fence (or 2671 * null for end). At top-level, for ascending cases, the first 2672 * split uses the root as left-fence/right-origin. From there, 2673 * right-hand splits replace the current fence with its left 2674 * child, also serving as origin for the split-off spliterator. 2675 * Left-hands are symmetric. Descending versions place the origin 2676 * at the end and invert ascending split rules. This base class 2677 * is non-commital about directionality, or whether the top-level 2678 * spliterator covers the whole tree. This means that the actual 2679 * split mechanics are located in subclasses. Some of the subclass 2680 * trySplit methods are identical (except for return types), but 2681 * not nicely factorable. 2682 * 2683 * Currently, subclass versions exist only for the full map 2684 * (including descending keys via its descendingMap). Others are 2685 * possible but currently not worthwhile because submaps require 2686 * O(n) computations to determine size, which substantially limits 2687 * potential speed-ups of using custom Spliterators versus default 2688 * mechanics. 2689 * 2690 * To boostrap initialization, external constructors use 2691 * negative size estimates: -1 for ascend, -2 for descend. 2692 */ 2693 static class TreeMapSpliterator<K,V> { 2694 final TreeMap<K,V> tree; 2695 TreeMapEntry<K,V> current; // traverser; initially first node in range 2696 TreeMapEntry<K,V> fence; // one past last, or null 2697 int side; // 0: top, -1: is a left split, +1: right 2698 int est; // size estimate (exact only for top-level) 2699 int expectedModCount; // for CME checks 2700 2701 TreeMapSpliterator(TreeMap<K,V> tree, 2702 TreeMapEntry<K,V> origin, TreeMapEntry<K,V> fence, 2703 int side, int est, int expectedModCount) { 2704 this.tree = tree; 2705 this.current = origin; 2706 this.fence = fence; 2707 this.side = side; 2708 this.est = est; 2709 this.expectedModCount = expectedModCount; 2710 } 2711 2712 final int getEstimate() { // force initialization 2713 int s; TreeMap<K,V> t; 2714 if ((s = est) < 0) { 2715 if ((t = tree) != null) { 2716 current = (s == -1) ? t.getFirstEntry() : t.getLastEntry(); 2717 s = est = t.size; 2718 expectedModCount = t.modCount; 2719 } 2720 else 2721 s = est = 0; 2722 } 2723 return s; 2724 } 2725 2726 public final long estimateSize() { 2727 return (long)getEstimate(); 2728 } 2729 } 2730 2731 static final class KeySpliterator<K,V> 2732 extends TreeMapSpliterator<K,V> 2733 implements Spliterator<K> { 2734 KeySpliterator(TreeMap<K,V> tree, 2735 TreeMapEntry<K,V> origin, TreeMapEntry<K,V> fence, 2736 int side, int est, int expectedModCount) { 2737 super(tree, origin, fence, side, est, expectedModCount); 2738 } 2739 2740 public KeySpliterator<K,V> trySplit() { 2741 if (est < 0) 2742 getEstimate(); // force initialization 2743 int d = side; 2744 TreeMapEntry<K,V> e = current, f = fence, 2745 s = ((e == null || e == f) ? null : // empty 2746 (d == 0) ? tree.root : // was top 2747 (d > 0) ? e.right : // was right 2748 (d < 0 && f != null) ? f.left : // was left 2749 null); 2750 if (s != null && s != e && s != f && 2751 tree.compare(e.key, s.key) < 0) { // e not already past s 2752 side = 1; 2753 return new KeySpliterator<> 2754 (tree, e, current = s, -1, est >>>= 1, expectedModCount); 2755 } 2756 return null; 2757 } 2758 2759 public void forEachRemaining(Consumer<? super K> action) { 2760 if (action == null) 2761 throw new NullPointerException(); 2762 if (est < 0) 2763 getEstimate(); // force initialization 2764 TreeMapEntry<K,V> f = fence, e, p, pl; 2765 if ((e = current) != null && e != f) { 2766 current = f; // exhaust 2767 do { 2768 action.accept(e.key); 2769 if ((p = e.right) != null) { 2770 while ((pl = p.left) != null) 2771 p = pl; 2772 } 2773 else { 2774 while ((p = e.parent) != null && e == p.right) 2775 e = p; 2776 } 2777 } while ((e = p) != null && e != f); 2778 if (tree.modCount != expectedModCount) 2779 throw new ConcurrentModificationException(); 2780 } 2781 } 2782 2783 public boolean tryAdvance(Consumer<? super K> action) { 2784 TreeMapEntry<K,V> e; 2785 if (action == null) 2786 throw new NullPointerException(); 2787 if (est < 0) 2788 getEstimate(); // force initialization 2789 if ((e = current) == null || e == fence) 2790 return false; 2791 current = successor(e); 2792 action.accept(e.key); 2793 if (tree.modCount != expectedModCount) 2794 throw new ConcurrentModificationException(); 2795 return true; 2796 } 2797 2798 public int characteristics() { 2799 return (side == 0 ? Spliterator.SIZED : 0) | 2800 Spliterator.DISTINCT | Spliterator.SORTED | Spliterator.ORDERED; 2801 } 2802 2803 public final Comparator<? super K> getComparator() { 2804 return tree.comparator; 2805 } 2806 2807 } 2808 2809 static final class DescendingKeySpliterator<K,V> 2810 extends TreeMapSpliterator<K,V> 2811 implements Spliterator<K> { 2812 DescendingKeySpliterator(TreeMap<K,V> tree, 2813 TreeMapEntry<K,V> origin, TreeMapEntry<K,V> fence, 2814 int side, int est, int expectedModCount) { 2815 super(tree, origin, fence, side, est, expectedModCount); 2816 } 2817 2818 public DescendingKeySpliterator<K,V> trySplit() { 2819 if (est < 0) 2820 getEstimate(); // force initialization 2821 int d = side; 2822 TreeMapEntry<K,V> e = current, f = fence, 2823 s = ((e == null || e == f) ? null : // empty 2824 (d == 0) ? tree.root : // was top 2825 (d < 0) ? e.left : // was left 2826 (d > 0 && f != null) ? f.right : // was right 2827 null); 2828 if (s != null && s != e && s != f && 2829 tree.compare(e.key, s.key) > 0) { // e not already past s 2830 side = 1; 2831 return new DescendingKeySpliterator<> 2832 (tree, e, current = s, -1, est >>>= 1, expectedModCount); 2833 } 2834 return null; 2835 } 2836 2837 public void forEachRemaining(Consumer<? super K> action) { 2838 if (action == null) 2839 throw new NullPointerException(); 2840 if (est < 0) 2841 getEstimate(); // force initialization 2842 TreeMapEntry<K,V> f = fence, e, p, pr; 2843 if ((e = current) != null && e != f) { 2844 current = f; // exhaust 2845 do { 2846 action.accept(e.key); 2847 if ((p = e.left) != null) { 2848 while ((pr = p.right) != null) 2849 p = pr; 2850 } 2851 else { 2852 while ((p = e.parent) != null && e == p.left) 2853 e = p; 2854 } 2855 } while ((e = p) != null && e != f); 2856 if (tree.modCount != expectedModCount) 2857 throw new ConcurrentModificationException(); 2858 } 2859 } 2860 2861 public boolean tryAdvance(Consumer<? super K> action) { 2862 TreeMapEntry<K,V> e; 2863 if (action == null) 2864 throw new NullPointerException(); 2865 if (est < 0) 2866 getEstimate(); // force initialization 2867 if ((e = current) == null || e == fence) 2868 return false; 2869 current = predecessor(e); 2870 action.accept(e.key); 2871 if (tree.modCount != expectedModCount) 2872 throw new ConcurrentModificationException(); 2873 return true; 2874 } 2875 2876 public int characteristics() { 2877 return (side == 0 ? Spliterator.SIZED : 0) | 2878 Spliterator.DISTINCT | Spliterator.ORDERED; 2879 } 2880 } 2881 2882 static final class ValueSpliterator<K,V> 2883 extends TreeMapSpliterator<K,V> 2884 implements Spliterator<V> { 2885 ValueSpliterator(TreeMap<K,V> tree, 2886 TreeMapEntry<K,V> origin, TreeMapEntry<K,V> fence, 2887 int side, int est, int expectedModCount) { 2888 super(tree, origin, fence, side, est, expectedModCount); 2889 } 2890 2891 public ValueSpliterator<K,V> trySplit() { 2892 if (est < 0) 2893 getEstimate(); // force initialization 2894 int d = side; 2895 TreeMapEntry<K,V> e = current, f = fence, 2896 s = ((e == null || e == f) ? null : // empty 2897 (d == 0) ? tree.root : // was top 2898 (d > 0) ? e.right : // was right 2899 (d < 0 && f != null) ? f.left : // was left 2900 null); 2901 if (s != null && s != e && s != f && 2902 tree.compare(e.key, s.key) < 0) { // e not already past s 2903 side = 1; 2904 return new ValueSpliterator<> 2905 (tree, e, current = s, -1, est >>>= 1, expectedModCount); 2906 } 2907 return null; 2908 } 2909 2910 public void forEachRemaining(Consumer<? super V> action) { 2911 if (action == null) 2912 throw new NullPointerException(); 2913 if (est < 0) 2914 getEstimate(); // force initialization 2915 TreeMapEntry<K,V> f = fence, e, p, pl; 2916 if ((e = current) != null && e != f) { 2917 current = f; // exhaust 2918 do { 2919 action.accept(e.value); 2920 if ((p = e.right) != null) { 2921 while ((pl = p.left) != null) 2922 p = pl; 2923 } 2924 else { 2925 while ((p = e.parent) != null && e == p.right) 2926 e = p; 2927 } 2928 } while ((e = p) != null && e != f); 2929 if (tree.modCount != expectedModCount) 2930 throw new ConcurrentModificationException(); 2931 } 2932 } 2933 2934 public boolean tryAdvance(Consumer<? super V> action) { 2935 TreeMapEntry<K,V> e; 2936 if (action == null) 2937 throw new NullPointerException(); 2938 if (est < 0) 2939 getEstimate(); // force initialization 2940 if ((e = current) == null || e == fence) 2941 return false; 2942 current = successor(e); 2943 action.accept(e.value); 2944 if (tree.modCount != expectedModCount) 2945 throw new ConcurrentModificationException(); 2946 return true; 2947 } 2948 2949 public int characteristics() { 2950 return (side == 0 ? Spliterator.SIZED : 0) | Spliterator.ORDERED; 2951 } 2952 } 2953 2954 static final class EntrySpliterator<K,V> 2955 extends TreeMapSpliterator<K,V> 2956 implements Spliterator<Map.Entry<K,V>> { 2957 EntrySpliterator(TreeMap<K,V> tree, 2958 TreeMapEntry<K,V> origin, TreeMapEntry<K,V> fence, 2959 int side, int est, int expectedModCount) { 2960 super(tree, origin, fence, side, est, expectedModCount); 2961 } 2962 2963 public EntrySpliterator<K,V> trySplit() { 2964 if (est < 0) 2965 getEstimate(); // force initialization 2966 int d = side; 2967 TreeMapEntry<K,V> e = current, f = fence, 2968 s = ((e == null || e == f) ? null : // empty 2969 (d == 0) ? tree.root : // was top 2970 (d > 0) ? e.right : // was right 2971 (d < 0 && f != null) ? f.left : // was left 2972 null); 2973 if (s != null && s != e && s != f && 2974 tree.compare(e.key, s.key) < 0) { // e not already past s 2975 side = 1; 2976 return new EntrySpliterator<> 2977 (tree, e, current = s, -1, est >>>= 1, expectedModCount); 2978 } 2979 return null; 2980 } 2981 2982 public void forEachRemaining(Consumer<? super Map.Entry<K, V>> action) { 2983 if (action == null) 2984 throw new NullPointerException(); 2985 if (est < 0) 2986 getEstimate(); // force initialization 2987 TreeMapEntry<K,V> f = fence, e, p, pl; 2988 if ((e = current) != null && e != f) { 2989 current = f; // exhaust 2990 do { 2991 action.accept(e); 2992 if ((p = e.right) != null) { 2993 while ((pl = p.left) != null) 2994 p = pl; 2995 } 2996 else { 2997 while ((p = e.parent) != null && e == p.right) 2998 e = p; 2999 } 3000 } while ((e = p) != null && e != f); 3001 if (tree.modCount != expectedModCount) 3002 throw new ConcurrentModificationException(); 3003 } 3004 } 3005 3006 public boolean tryAdvance(Consumer<? super Map.Entry<K,V>> action) { 3007 TreeMapEntry<K,V> e; 3008 if (action == null) 3009 throw new NullPointerException(); 3010 if (est < 0) 3011 getEstimate(); // force initialization 3012 if ((e = current) == null || e == fence) 3013 return false; 3014 current = successor(e); 3015 action.accept(e); 3016 if (tree.modCount != expectedModCount) 3017 throw new ConcurrentModificationException(); 3018 return true; 3019 } 3020 3021 public int characteristics() { 3022 return (side == 0 ? Spliterator.SIZED : 0) | 3023 Spliterator.DISTINCT | Spliterator.SORTED | Spliterator.ORDERED; 3024 } 3025 3026 @Override 3027 public Comparator<Map.Entry<K, V>> getComparator() { 3028 // Adapt or create a key-based comparator 3029 if (tree.comparator != null) { 3030 return Map.Entry.comparingByKey(tree.comparator); 3031 } 3032 else { 3033 return (Comparator<Map.Entry<K, V>> & Serializable) (e1, e2) -> { 3034 @SuppressWarnings("unchecked") 3035 Comparable<? super K> k1 = (Comparable<? super K>) e1.getKey(); 3036 return k1.compareTo(e2.getKey()); 3037 }; 3038 } 3039 } 3040 } 3041} 3042