1/* GENERATED SOURCE. DO NOT MODIFY. */ 2// © 2016 and later: Unicode, Inc. and others. 3// License & terms of use: http://www.unicode.org/copyright.html#License 4/* 5 ******************************************************************************* 6 * Copyright (C) 2008-2016, Google Inc, International Business Machines Corporation 7 * and others. All Rights Reserved. 8 ******************************************************************************* 9 */ 10package android.icu.text; 11 12import java.util.ArrayList; 13import java.util.Collections; 14import java.util.Comparator; 15import java.util.Iterator; 16import java.util.List; 17import java.util.Locale; 18 19import android.icu.lang.UCharacter; 20import android.icu.text.AlphabeticIndex.Bucket; 21import android.icu.text.AlphabeticIndex.Bucket.LabelType; 22import android.icu.util.LocaleData; 23import android.icu.util.ULocale; 24 25/** 26 * AlphabeticIndex supports the creation of a UI index appropriate for a given language. 27 * It can support either direct use, or use with a client that doesn't support localized collation. 28 * The following is an example of what an index might look like in a UI: 29 * 30 * <pre> 31 * <b>... A B C D E F G H I J K L M N O P Q R S T U V W X Y Z ...</b> 32 * 33 * <b>A</b> 34 * Addison 35 * Albertson 36 * Azensky 37 * <b>B</b> 38 * Baecker 39 * ... 40 * </pre> 41 * 42 * The class can generate a list of labels for use as a UI "index", that is, a list of 43 * clickable characters (or character sequences) that allow the user to see a segment 44 * (bucket) of a larger "target" list. That is, each label corresponds to a bucket in 45 * the target list, where everything in the bucket is greater than or equal to the character 46 * (according to the locale's collation). Strings can be added to the index; 47 * they will be in sorted order in the right bucket. 48 * <p> 49 * The class also supports having buckets for strings before the first (underflow), 50 * after the last (overflow), and between scripts (inflow). For example, if the index 51 * is constructed with labels for Russian and English, Greek characters would fall 52 * into an inflow bucket between the other two scripts. 53 * 54 * <p><em>Note:</em> If you expect to have a lot of ASCII or Latin characters 55 * as well as characters from the user's language, 56 * then it is a good idea to call addLabels(ULocale.English). 57 * 58 * <h2>Direct Use</h2> 59 * <p>The following shows an example of building an index directly. 60 * The "show..." methods below are just to illustrate usage. 61 * 62 * <pre> 63 * // Create a simple index where the values for the strings are Integers, and add the strings 64 * 65 * AlphabeticIndex<Integer> index = new AlphabeticIndex<Integer>(desiredLocale).addLabels(additionalLocale); 66 * int counter = 0; 67 * for (String item : test) { 68 * index.addRecord(item, counter++); 69 * } 70 * ... 71 * // Show index at top. We could skip or gray out empty buckets 72 * 73 * for (AlphabeticIndex.Bucket<Integer> bucket : index) { 74 * if (showAll || bucket.size() != 0) { 75 * showLabelAtTop(UI, bucket.getLabel()); 76 * } 77 * } 78 * ... 79 * // Show the buckets with their contents, skipping empty buckets 80 * 81 * for (AlphabeticIndex.Bucket<Integer> bucket : index) { 82 * if (bucket.size() != 0) { 83 * showLabelInList(UI, bucket.getLabel()); 84 * for (AlphabeticIndex.Record<Integer> item : bucket) { 85 * showIndexedItem(UI, item.getName(), item.getData()); 86 * } 87 * </pre> 88 * 89 * The caller can build different UIs using this class. 90 * For example, an index character could be omitted or grayed-out 91 * if its bucket is empty. Small buckets could also be combined based on size, such as: 92 * 93 * <pre> 94 * <b>... A-F G-N O-Z ...</b> 95 * </pre> 96 * 97 * <h2>Client Support</h2> 98 * <p>Callers can also use the {@link AlphabeticIndex.ImmutableIndex}, or the AlphabeticIndex itself, 99 * to support sorting on a client that doesn't support AlphabeticIndex functionality. 100 * 101 * <p>The ImmutableIndex is both immutable and thread-safe. 102 * The corresponding AlphabeticIndex methods are not thread-safe because 103 * they "lazily" build the index buckets. 104 * <ul> 105 * <li>ImmutableIndex.getBucket(index) provides random access to all 106 * buckets and their labels and label types. 107 * <li>AlphabeticIndex.getBucketLabels() or the bucket iterator on either class 108 * can be used to get a list of the labels, 109 * such as "...", "A", "B",..., and send that list to the client. 110 * <li>When the client has a new name, it sends that name to the server. 111 * The server needs to call the following methods, 112 * and communicate the bucketIndex and collationKey back to the client. 113 * 114 * <pre> 115 * int bucketIndex = index.getBucketIndex(name); 116 * String label = immutableIndex.getBucket(bucketIndex).getLabel(); // optional 117 * RawCollationKey collationKey = collator.getRawCollationKey(name, null); 118 * </pre> 119 * 120 * <li>The client would put the name (and associated information) into its bucket for bucketIndex. The collationKey is a 121 * sequence of bytes that can be compared with a binary compare, and produce the right localized result.</li> 122 * </ul> 123 * 124 * @author Mark Davis 125 */ 126public final class AlphabeticIndex<V> implements Iterable<Bucket<V>> { 127 /** 128 * Prefix string for Chinese index buckets. 129 * See http://unicode.org/repos/cldr/trunk/specs/ldml/tr35-collation.html#Collation_Indexes 130 */ 131 private static final String BASE = "\uFDD0"; 132 133 private static final char CGJ = '\u034F'; 134 135 private static final Comparator<String> binaryCmp = new UTF16.StringComparator(true, false, 0); 136 137 private final RuleBasedCollator collatorOriginal; 138 private final RuleBasedCollator collatorPrimaryOnly; 139 private RuleBasedCollator collatorExternal; 140 141 // Comparator for records, so that the Record class can be static. 142 private final Comparator<Record<V>> recordComparator = new Comparator<Record<V>>() { 143 @Override 144 public int compare(Record<V> o1, Record<V> o2) { 145 return collatorOriginal.compare(o1.name, o2.name); 146 } 147 }; 148 149 private final List<String> firstCharsInScripts; 150 151 // We accumulate these as we build up the input parameters 152 private final UnicodeSet initialLabels = new UnicodeSet(); 153 private List<Record<V>> inputList; 154 155 // Lazy evaluated: null means that we have not built yet. 156 private BucketList<V> buckets; 157 158 private String overflowLabel = "\u2026"; 159 private String underflowLabel = "\u2026"; 160 private String inflowLabel = "\u2026"; 161 162 /** 163 * Immutable, thread-safe version of {@link AlphabeticIndex}. 164 * This class provides thread-safe methods for bucketing, 165 * and random access to buckets and their properties, 166 * but does not offer adding records to the index. 167 * 168 * @param <V> The Record value type is unused. It can be omitted for this class 169 * if it was omitted for the AlphabeticIndex that built it. 170 */ 171 public static final class ImmutableIndex<V> implements Iterable<Bucket<V>> { 172 private final BucketList<V> buckets; 173 private final Collator collatorPrimaryOnly; 174 175 private ImmutableIndex(BucketList<V> bucketList, Collator collatorPrimaryOnly) { 176 this.buckets = bucketList; 177 this.collatorPrimaryOnly = collatorPrimaryOnly; 178 } 179 180 /** 181 * Returns the number of index buckets and labels, including underflow/inflow/overflow. 182 * 183 * @return the number of index buckets 184 */ 185 public int getBucketCount() { 186 return buckets.getBucketCount(); 187 } 188 189 /** 190 * Finds the index bucket for the given name and returns the number of that bucket. 191 * Use {@link #getBucket(int)} to get the bucket's properties. 192 * 193 * @param name the string to be sorted into an index bucket 194 * @return the bucket number for the name 195 */ 196 public int getBucketIndex(CharSequence name) { 197 return buckets.getBucketIndex(name, collatorPrimaryOnly); 198 } 199 200 /** 201 * Returns the index-th bucket. Returns null if the index is out of range. 202 * 203 * @param index bucket number 204 * @return the index-th bucket 205 */ 206 public Bucket<V> getBucket(int index) { 207 if (0 <= index && index < buckets.getBucketCount()) { 208 return buckets.immutableVisibleList.get(index); 209 } else { 210 return null; 211 } 212 } 213 214 /** 215 * {@inheritDoc} 216 */ 217 @Override 218 public Iterator<Bucket<V>> iterator() { 219 return buckets.iterator(); 220 } 221 } 222 223 /** 224 * Create the index object. 225 * 226 * @param locale 227 * The locale for the index. 228 */ 229 public AlphabeticIndex(ULocale locale) { 230 this(locale, null); 231 } 232 233 /** 234 * Create the index object. 235 * 236 * @param locale 237 * The locale for the index. 238 */ 239 public AlphabeticIndex(Locale locale) { 240 this(ULocale.forLocale(locale), null); 241 } 242 243 /** 244 * Create an AlphabeticIndex that uses a specific collator. 245 * 246 * <p>The index will be created with no labels; the addLabels() function must be called 247 * after creation to add the desired labels to the index. 248 * 249 * <p>The index will work directly with the supplied collator. If the caller will need to 250 * continue working with the collator it should be cloned first, so that the 251 * collator provided to the AlphabeticIndex remains unchanged after creation of the index. 252 * 253 * @param collator The collator to use to order the contents of this index. 254 */ 255 public AlphabeticIndex(RuleBasedCollator collator) { 256 this(null, collator); 257 } 258 259 /** 260 * Internal constructor containing implementation used by public constructors. 261 */ 262 private AlphabeticIndex(ULocale locale, RuleBasedCollator collator) { 263 collatorOriginal = collator != null ? collator : (RuleBasedCollator) Collator.getInstance(locale); 264 try { 265 collatorPrimaryOnly = collatorOriginal.cloneAsThawed(); 266 } catch (Exception e) { 267 // should never happen 268 throw new IllegalStateException("Collator cannot be cloned", e); 269 } 270 collatorPrimaryOnly.setStrength(Collator.PRIMARY); 271 collatorPrimaryOnly.freeze(); 272 273 firstCharsInScripts = getFirstCharactersInScripts(); 274 Collections.sort(firstCharsInScripts, collatorPrimaryOnly); 275 // Guard against a degenerate collator where 276 // some script boundary strings are primary ignorable. 277 for (;;) { 278 if (firstCharsInScripts.isEmpty()) { 279 throw new IllegalArgumentException( 280 "AlphabeticIndex requires some non-ignorable script boundary strings"); 281 } 282 if (collatorPrimaryOnly.compare(firstCharsInScripts.get(0), "") == 0) { 283 firstCharsInScripts.remove(0); 284 } else { 285 break; 286 } 287 } 288 289 // Chinese index characters, which are specific to each of the several Chinese tailorings, 290 // take precedence over the single locale data exemplar set per language. 291 if (!addChineseIndexCharacters() && locale != null) { 292 addIndexExemplars(locale); 293 } 294 } 295 296 /** 297 * Add more index characters (aside from what are in the locale) 298 * @param additions additional characters to add to the index, such as A-Z. 299 * @return this, for chaining 300 */ 301 public AlphabeticIndex<V> addLabels(UnicodeSet additions) { 302 initialLabels.addAll(additions); 303 buckets = null; 304 return this; 305 } 306 307 /** 308 * Add more index characters (aside from what are in the locale) 309 * @param additions additional characters to add to the index, such as those in Swedish. 310 * @return this, for chaining 311 */ 312 public AlphabeticIndex<V> addLabels(ULocale... additions) { 313 for (ULocale addition : additions) { 314 addIndexExemplars(addition); 315 } 316 buckets = null; 317 return this; 318 } 319 320 /** 321 * Add more index characters (aside from what are in the locale) 322 * @param additions additional characters to add to the index, such as those in Swedish. 323 * @return this, for chaining 324 */ 325 public AlphabeticIndex<V> addLabels(Locale... additions) { 326 for (Locale addition : additions) { 327 addIndexExemplars(ULocale.forLocale(addition)); 328 } 329 buckets = null; 330 return this; 331 } 332 333 /** 334 * Set the overflow label 335 * @param overflowLabel see class description 336 * @return this, for chaining 337 */ 338 public AlphabeticIndex<V> setOverflowLabel(String overflowLabel) { 339 this.overflowLabel = overflowLabel; 340 buckets = null; 341 return this; 342 } 343 344 /** 345 * Get the default label used in the IndexCharacters' locale for underflow, eg the last item in: X Y Z ... 346 * 347 * @return underflow label 348 */ 349 public String getUnderflowLabel() { 350 return underflowLabel; // TODO get localized version 351 } 352 353 354 /** 355 * Set the underflowLabel label 356 * @param underflowLabel see class description 357 * @return this, for chaining 358 */ 359 public AlphabeticIndex<V> setUnderflowLabel(String underflowLabel) { 360 this.underflowLabel = underflowLabel; 361 buckets = null; 362 return this; 363 } 364 365 /** 366 * Get the default label used in the IndexCharacters' locale for overflow, eg the first item in: ... A B C 367 * 368 * @return overflow label 369 */ 370 public String getOverflowLabel() { 371 return overflowLabel; // TODO get localized version 372 } 373 374 375 /** 376 * Set the inflowLabel label 377 * @param inflowLabel see class description 378 * @return this, for chaining 379 */ 380 public AlphabeticIndex<V> setInflowLabel(String inflowLabel) { 381 this.inflowLabel = inflowLabel; 382 buckets = null; 383 return this; 384 } 385 386 /** 387 * Get the default label used for abbreviated buckets <i>between</i> other labels. For example, consider the labels 388 * for Latin and Greek are used: X Y Z ... Α Β Γ. 389 * 390 * @return inflow label 391 */ 392 public String getInflowLabel() { 393 return inflowLabel; // TODO get localized version 394 } 395 396 397 /** 398 * Get the limit on the number of labels in the index. The number of buckets can be slightly larger: see getBucketCount(). 399 * 400 * @return maxLabelCount maximum number of labels. 401 */ 402 public int getMaxLabelCount() { 403 return maxLabelCount; 404 } 405 406 /** 407 * Set a limit on the number of labels in the index. The number of buckets can be slightly larger: see 408 * getBucketCount(). 409 * 410 * @param maxLabelCount Set the maximum number of labels. Currently, if the number is exceeded, then every 411 * nth item is removed to bring the count down. A more sophisticated mechanism may be available in the 412 * future. 413 * @return this, for chaining 414 */ 415 public AlphabeticIndex<V> setMaxLabelCount(int maxLabelCount) { 416 this.maxLabelCount = maxLabelCount; 417 buckets = null; 418 return this; 419 } 420 421 /** 422 * Determine the best labels to use. This is based on the exemplars, but we also process to make sure that they are unique, 423 * and sort differently, and that the overall list is small enough. 424 */ 425 private List<String> initLabels() { 426 Normalizer2 nfkdNormalizer = Normalizer2.getNFKDInstance(); 427 List<String> indexCharacters = new ArrayList<String>(); 428 429 String firstScriptBoundary = firstCharsInScripts.get(0); 430 String overflowBoundary = firstCharsInScripts.get(firstCharsInScripts.size() - 1); 431 432 // We make a sorted array of elements. 433 // Some of the input may be redundant. 434 // That is, we might have c, ch, d, where "ch" sorts just like "c", "h". 435 // We filter out those cases. 436 for (String item : initialLabels) { 437 boolean checkDistinct; 438 if (!UTF16.hasMoreCodePointsThan(item, 1)) { 439 checkDistinct = false; 440 } else if(item.charAt(item.length() - 1) == '*' && 441 item.charAt(item.length() - 2) != '*') { 442 // Use a label if it is marked with one trailing star, 443 // even if the label string sorts the same when all contractions are suppressed. 444 item = item.substring(0, item.length() - 1); 445 checkDistinct = false; 446 } else { 447 checkDistinct = true; 448 } 449 if (collatorPrimaryOnly.compare(item, firstScriptBoundary) < 0) { 450 // Ignore a primary-ignorable or non-alphabetic index character. 451 } else if (collatorPrimaryOnly.compare(item, overflowBoundary) >= 0) { 452 // Ignore an index character that will land in the overflow bucket. 453 } else if (checkDistinct && collatorPrimaryOnly.compare(item, separated(item)) == 0) { 454 // Ignore a multi-code point index character that does not sort distinctly 455 // from the sequence of its separate characters. 456 } else { 457 int insertionPoint = Collections.binarySearch(indexCharacters, item, collatorPrimaryOnly); 458 if (insertionPoint < 0) { 459 indexCharacters.add(~insertionPoint, item); 460 } else { 461 String itemAlreadyIn = indexCharacters.get(insertionPoint); 462 if (isOneLabelBetterThanOther(nfkdNormalizer, item, itemAlreadyIn)) { 463 indexCharacters.set(insertionPoint, item); 464 } 465 } 466 } 467 } 468 469 // if the result is still too large, cut down to maxLabelCount elements, by removing every nth element 470 471 final int size = indexCharacters.size() - 1; 472 if (size > maxLabelCount) { 473 int count = 0; 474 int old = -1; 475 for (Iterator<String> it = indexCharacters.iterator(); it.hasNext();) { 476 ++count; 477 it.next(); 478 final int bump = count * maxLabelCount / size; 479 if (bump == old) { 480 it.remove(); 481 } else { 482 old = bump; 483 } 484 } 485 } 486 487 return indexCharacters; 488 } 489 490 private static String fixLabel(String current) { 491 if (!current.startsWith(BASE)) { 492 return current; 493 } 494 int rest = current.charAt(BASE.length()); 495 if (0x2800 < rest && rest <= 0x28FF) { // stroke count 496 return (rest-0x2800) + "\u5283"; 497 } 498 return current.substring(BASE.length()); 499 } 500 501 /** 502 * This method is called to get the index exemplars. Normally these come from the locale directly, 503 * but if they aren't available, we have to synthesize them. 504 */ 505 private void addIndexExemplars(ULocale locale) { 506 UnicodeSet exemplars = LocaleData.getExemplarSet(locale, 0, LocaleData.ES_INDEX); 507 if (exemplars != null) { 508 initialLabels.addAll(exemplars); 509 return; 510 } 511 512 // The locale data did not include explicit Index characters. 513 // Synthesize a set of them from the locale's standard exemplar characters. 514 exemplars = LocaleData.getExemplarSet(locale, 0, LocaleData.ES_STANDARD); 515 516 exemplars = exemplars.cloneAsThawed(); 517 // question: should we add auxiliary exemplars? 518 if (exemplars.containsSome('a', 'z') || exemplars.size() == 0) { 519 exemplars.addAll('a', 'z'); 520 } 521 if (exemplars.containsSome(0xAC00, 0xD7A3)) { // Hangul syllables 522 // cut down to small list 523 exemplars.remove(0xAC00, 0xD7A3). 524 add(0xAC00).add(0xB098).add(0xB2E4).add(0xB77C). 525 add(0xB9C8).add(0xBC14).add(0xC0AC).add(0xC544). 526 add(0xC790).add(0xCC28).add(0xCE74).add(0xD0C0). 527 add(0xD30C).add(0xD558); 528 } 529 if (exemplars.containsSome(0x1200, 0x137F)) { // Ethiopic block 530 // cut down to small list 531 // make use of the fact that Ethiopic is allocated in 8's, where 532 // the base is 0 mod 8. 533 UnicodeSet ethiopic = new UnicodeSet("[[:Block=Ethiopic:]&[:Script=Ethiopic:]]"); 534 UnicodeSetIterator it = new UnicodeSetIterator(ethiopic); 535 while (it.next() && it.codepoint != UnicodeSetIterator.IS_STRING) { 536 if ((it.codepoint & 0x7) != 0) { 537 exemplars.remove(it.codepoint); 538 } 539 } 540 } 541 542 // Upper-case any that aren't already so. 543 // (We only do this for synthesized index characters.) 544 for (String item : exemplars) { 545 initialLabels.add(UCharacter.toUpperCase(locale, item)); 546 } 547 } 548 549 /** 550 * Add Chinese index characters from the tailoring. 551 */ 552 private boolean addChineseIndexCharacters() { 553 UnicodeSet contractions = new UnicodeSet(); 554 try { 555 collatorPrimaryOnly.internalAddContractions(BASE.charAt(0), contractions); 556 } catch (Exception e) { 557 return false; 558 } 559 if (contractions.isEmpty()) { return false; } 560 initialLabels.addAll(contractions); 561 for (String s : contractions) { 562 assert(s.startsWith(BASE)); 563 char c = s.charAt(s.length() - 1); 564 if (0x41 <= c && c <= 0x5A) { // A-Z 565 // There are Pinyin labels, add ASCII A-Z labels as well. 566 initialLabels.add(0x41, 0x5A); // A-Z 567 break; 568 } 569 } 570 return true; 571 } 572 573 /** 574 * Return the string with interspersed CGJs. Input must have more than 2 codepoints. 575 * <p>This is used to test whether contractions sort differently from their components. 576 */ 577 private String separated(String item) { 578 StringBuilder result = new StringBuilder(); 579 // add a CGJ except within surrogates 580 char last = item.charAt(0); 581 result.append(last); 582 for (int i = 1; i < item.length(); ++i) { 583 char ch = item.charAt(i); 584 if (!UCharacter.isHighSurrogate(last) || !UCharacter.isLowSurrogate(ch)) { 585 result.append(CGJ); 586 } 587 result.append(ch); 588 last = ch; 589 } 590 return result.toString(); 591 } 592 593 /** 594 * Builds an immutable, thread-safe version of this instance, without data records. 595 * 596 * @return an immutable index instance 597 */ 598 public ImmutableIndex<V> buildImmutableIndex() { 599 // The current AlphabeticIndex Java code never modifies the bucket list once built. 600 // If it contains no records, we can use it. 601 // addRecord() sets buckets=null rather than inserting the new record into it. 602 BucketList<V> immutableBucketList; 603 if (inputList != null && !inputList.isEmpty()) { 604 // We need a bucket list with no records. 605 immutableBucketList = createBucketList(); 606 } else { 607 if (buckets == null) { 608 buckets = createBucketList(); 609 } 610 immutableBucketList = buckets; 611 } 612 return new ImmutableIndex<V>(immutableBucketList, collatorPrimaryOnly); 613 } 614 615 /** 616 * Get the labels. 617 * 618 * @return The list of bucket labels, after processing. 619 */ 620 public List<String> getBucketLabels() { 621 initBuckets(); 622 ArrayList<String> result = new ArrayList<String>(); 623 for (Bucket<V> bucket : buckets) { 624 result.add(bucket.getLabel()); 625 } 626 return result; 627 } 628 629 /** 630 * Get a clone of the collator used internally. Note that for performance reasons, the clone is only done once, and 631 * then stored. The next time it is accessed, the same instance is returned. 632 * <p> 633 * <b><i>Don't use this method across threads if you are changing the settings on the collator, at least not without 634 * synchronizing.</i></b> 635 * 636 * @return a clone of the collator used internally 637 */ 638 public RuleBasedCollator getCollator() { 639 if (collatorExternal == null) { 640 try { 641 collatorExternal = (RuleBasedCollator) (collatorOriginal.clone()); 642 } catch (Exception e) { 643 // should never happen 644 throw new IllegalStateException("Collator cannot be cloned", e); 645 } 646 } 647 return collatorExternal; 648 } 649 650 /** 651 * Add a record (name and data) to the index. The name will be used to sort the items into buckets, and to sort 652 * within the bucket. Two records may have the same name. When they do, the sort order is according to the order added: 653 * the first added comes first. 654 * 655 * @param name 656 * Name, such as a name 657 * @param data 658 * Data, such as an address or link 659 * @return this, for chaining 660 */ 661 public AlphabeticIndex<V> addRecord(CharSequence name, V data) { 662 // TODO instead of invalidating, just add to unprocessed list. 663 buckets = null; // invalidate old bucketlist 664 if (inputList == null) { 665 inputList = new ArrayList<Record<V>>(); 666 } 667 inputList.add(new Record<V>(name, data)); 668 return this; 669 } 670 671 /** 672 * Get the bucket number for the given name. This routine permits callers to implement their own bucket handling 673 * mechanisms, including client-server handling. For example, when a new name is created on the client, it can ask 674 * the server for the bucket for that name, and the sortkey (using getCollator). Once the client has that 675 * information, it can put the name into the right bucket, and sort it within that bucket, without having access to 676 * the index or collator. 677 * <p> 678 * Note that the bucket number (and sort key) are only valid for the settings of the current AlphabeticIndex; if 679 * those are changed, then the bucket number and sort key must be regenerated. 680 * 681 * @param name 682 * Name, such as a name 683 * @return the bucket index for the name 684 */ 685 public int getBucketIndex(CharSequence name) { 686 initBuckets(); 687 return buckets.getBucketIndex(name, collatorPrimaryOnly); 688 } 689 690 /** 691 * Clear the index. 692 * 693 * @return this, for chaining 694 */ 695 public AlphabeticIndex<V> clearRecords() { 696 if (inputList != null && !inputList.isEmpty()) { 697 inputList.clear(); 698 buckets = null; 699 } 700 return this; 701 } 702 703 /** 704 * Return the number of buckets in the index. This will be the same as the number of labels, plus buckets for the underflow, overflow, and inflow(s). 705 * 706 * @return number of buckets 707 */ 708 public int getBucketCount() { 709 initBuckets(); 710 return buckets.getBucketCount(); 711 } 712 713 /** 714 * Return the number of records in the index: that is, the total number of distinct <name,data> pairs added with addRecord(...), over all the buckets. 715 * 716 * @return total number of records in buckets 717 */ 718 public int getRecordCount() { 719 return inputList != null ? inputList.size() : 0; 720 } 721 722 /** 723 * Return an iterator over the buckets. 724 * 725 * @return iterator over buckets. 726 */ 727 @Override 728 public Iterator<Bucket<V>> iterator() { 729 initBuckets(); 730 return buckets.iterator(); 731 } 732 733 /** 734 * Creates an index, and buckets and sorts the list of records into the index. 735 */ 736 private void initBuckets() { 737 if (buckets != null) { 738 return; 739 } 740 buckets = createBucketList(); 741 if (inputList == null || inputList.isEmpty()) { 742 return; 743 } 744 745 // Sort the records by name. 746 // Stable sort preserves input order of collation duplicates. 747 Collections.sort(inputList, recordComparator); 748 749 // Now, we traverse all of the input, which is now sorted. 750 // If the item doesn't go in the current bucket, we find the next bucket that contains it. 751 // This makes the process order n*log(n), since we just sort the list and then do a linear process. 752 // However, if the user adds an item at a time and then gets the buckets, this isn't efficient, so 753 // we need to improve it for that case. 754 755 Iterator<Bucket<V>> bucketIterator = buckets.fullIterator(); 756 Bucket<V> currentBucket = bucketIterator.next(); 757 Bucket<V> nextBucket; 758 String upperBoundary; 759 if (bucketIterator.hasNext()) { 760 nextBucket = bucketIterator.next(); 761 upperBoundary = nextBucket.lowerBoundary; 762 } else { 763 nextBucket = null; 764 upperBoundary = null; 765 } 766 for (Record<V> r : inputList) { 767 // if the current bucket isn't the right one, find the one that is 768 // We have a special flag for the last bucket so that we don't look any further 769 while (upperBoundary != null && 770 collatorPrimaryOnly.compare(r.name, upperBoundary) >= 0) { 771 currentBucket = nextBucket; 772 // now reset the boundary that we compare against 773 if (bucketIterator.hasNext()) { 774 nextBucket = bucketIterator.next(); 775 upperBoundary = nextBucket.lowerBoundary; 776 } else { 777 upperBoundary = null; 778 } 779 } 780 // now put the record into the bucket. 781 Bucket<V> bucket = currentBucket; 782 if (bucket.displayBucket != null) { 783 bucket = bucket.displayBucket; 784 } 785 if (bucket.records == null) { 786 bucket.records = new ArrayList<Record<V>>(); 787 } 788 bucket.records.add(r); 789 } 790 } 791 792 private int maxLabelCount = 99; 793 794 /** 795 * Returns true if one index character string is "better" than the other. 796 * Shorter NFKD is better, and otherwise NFKD-binary-less-than is 797 * better, and otherwise binary-less-than is better. 798 */ 799 private static boolean isOneLabelBetterThanOther(Normalizer2 nfkdNormalizer, String one, String other) { 800 // This is called with primary-equal strings, but never with one.equals(other). 801 String n1 = nfkdNormalizer.normalize(one); 802 String n2 = nfkdNormalizer.normalize(other); 803 int result = n1.codePointCount(0, n1.length()) - n2.codePointCount(0, n2.length()); 804 if (result != 0) { 805 return result < 0; 806 } 807 result = binaryCmp.compare(n1, n2); 808 if (result != 0) { 809 return result < 0; 810 } 811 return binaryCmp.compare(one, other) < 0; 812 } 813 814 /** 815 * A (name, data) pair, to be sorted by name into one of the index buckets. 816 * The user data is not used by the index implementation. 817 */ 818 public static class Record<V> { 819 private final CharSequence name; 820 private final V data; 821 822 private Record(CharSequence name, V data) { 823 this.name = name; 824 this.data = data; 825 } 826 827 /** 828 * Get the name 829 * 830 * @return the name 831 */ 832 public CharSequence getName() { 833 return name; 834 } 835 836 /** 837 * Get the data 838 * 839 * @return the data 840 */ 841 public V getData() { 842 return data; 843 } 844 845 /** 846 * Standard toString() 847 */ 848 @Override 849 public String toString() { 850 return name + "=" + data; 851 } 852 } 853 854 /** 855 * An index "bucket" with a label string and type. 856 * It is referenced by {@link AlphabeticIndex#getBucketIndex(CharSequence)} 857 * and {@link AlphabeticIndex.ImmutableIndex#getBucketIndex(CharSequence)}, 858 * returned by {@link AlphabeticIndex.ImmutableIndex#getBucket(int)}, 859 * and {@link AlphabeticIndex#addRecord(CharSequence, Object)} adds a record 860 * into a bucket according to the record's name. 861 * 862 * @param <V> 863 * Data type 864 */ 865 public static class Bucket<V> implements Iterable<Record<V>> { 866 private final String label; 867 private final String lowerBoundary; 868 private final LabelType labelType; 869 private Bucket<V> displayBucket; 870 private int displayIndex; 871 private List<Record<V>> records; 872 873 /** 874 * Type of the label 875 */ 876 public enum LabelType { 877 /** 878 * Normal 879 */ 880 NORMAL, 881 /** 882 * Underflow (before the first) 883 */ 884 UNDERFLOW, 885 /** 886 * Inflow (between scripts) 887 */ 888 INFLOW, 889 /** 890 * Overflow (after the last) 891 */ 892 OVERFLOW 893 } 894 895 /** 896 * Set up the bucket. 897 * 898 * @param label 899 * label for the bucket 900 * @param labelType 901 * is an underflow, overflow, or inflow bucket 902 */ 903 private Bucket(String label, String lowerBoundary, LabelType labelType) { 904 this.label = label; 905 this.lowerBoundary = lowerBoundary; 906 this.labelType = labelType; 907 } 908 909 /** 910 * Get the label 911 * 912 * @return label for the bucket 913 */ 914 public String getLabel() { 915 return label; 916 } 917 918 /** 919 * Is a normal, underflow, overflow, or inflow bucket 920 * 921 * @return is an underflow, overflow, or inflow bucket 922 */ 923 public LabelType getLabelType() { 924 return labelType; 925 } 926 927 /** 928 * Get the number of records in the bucket. 929 * 930 * @return number of records in bucket 931 */ 932 public int size() { 933 return records == null ? 0 : records.size(); 934 } 935 936 /** 937 * Iterator over the records in the bucket 938 */ 939 @Override 940 public Iterator<Record<V>> iterator() { 941 if (records == null) { 942 return Collections.<Record<V>>emptyList().iterator(); 943 } 944 return records.iterator(); 945 } 946 947 /** 948 * Standard toString() 949 */ 950 @Override 951 public String toString() { 952 return "{" + 953 "labelType=" + labelType 954 + ", " + 955 "lowerBoundary=" + lowerBoundary 956 + ", " + 957 "label=" + label 958 + "}" 959 ; 960 } 961 } 962 963 private BucketList<V> createBucketList() { 964 // Initialize indexCharacters. 965 List<String> indexCharacters = initLabels(); 966 967 // Variables for hasMultiplePrimaryWeights(). 968 long variableTop; 969 if (collatorPrimaryOnly.isAlternateHandlingShifted()) { 970 variableTop = collatorPrimaryOnly.getVariableTop() & 0xffffffffL; 971 } else { 972 variableTop = 0; 973 } 974 boolean hasInvisibleBuckets = false; 975 976 // Helper arrays for Chinese Pinyin collation. 977 @SuppressWarnings({ "rawtypes", "unchecked" }) 978 Bucket<V>[] asciiBuckets = new Bucket[26]; 979 @SuppressWarnings({ "rawtypes", "unchecked" }) 980 Bucket<V>[] pinyinBuckets = new Bucket[26]; 981 boolean hasPinyin = false; 982 983 ArrayList<Bucket<V>> bucketList = new ArrayList<Bucket<V>>(); 984 985 // underflow bucket 986 bucketList.add(new Bucket<V>(getUnderflowLabel(), "", LabelType.UNDERFLOW)); 987 988 // fix up the list, adding underflow, additions, overflow 989 // Insert inflow labels as needed. 990 int scriptIndex = -1; 991 String scriptUpperBoundary = ""; 992 for (String current : indexCharacters) { 993 if (collatorPrimaryOnly.compare(current, scriptUpperBoundary) >= 0) { 994 // We crossed the script boundary into a new script. 995 String inflowBoundary = scriptUpperBoundary; 996 boolean skippedScript = false; 997 for (;;) { 998 scriptUpperBoundary = firstCharsInScripts.get(++scriptIndex); 999 if (collatorPrimaryOnly.compare(current, scriptUpperBoundary) < 0) { 1000 break; 1001 } 1002 skippedScript = true; 1003 } 1004 if (skippedScript && bucketList.size() > 1) { 1005 // We are skipping one or more scripts, 1006 // and we are not just getting out of the underflow label. 1007 bucketList.add(new Bucket<V>(getInflowLabel(), inflowBoundary, 1008 LabelType.INFLOW)); 1009 } 1010 } 1011 // Add a bucket with the current label. 1012 Bucket<V> bucket = new Bucket<V>(fixLabel(current), current, LabelType.NORMAL); 1013 bucketList.add(bucket); 1014 // Remember ASCII and Pinyin buckets for Pinyin redirects. 1015 char c; 1016 if (current.length() == 1 && 'A' <= (c = current.charAt(0)) && c <= 'Z') { 1017 asciiBuckets[c - 'A'] = bucket; 1018 } else if (current.length() == BASE.length() + 1 && current.startsWith(BASE) && 1019 'A' <= (c = current.charAt(BASE.length())) && c <= 'Z') { 1020 pinyinBuckets[c - 'A'] = bucket; 1021 hasPinyin = true; 1022 } 1023 // Check for multiple primary weights. 1024 if (!current.startsWith(BASE) && 1025 hasMultiplePrimaryWeights(collatorPrimaryOnly, variableTop, current) && 1026 !current.endsWith("\uffff")) { 1027 // "Æ" or "Sch" etc. 1028 for (int i = bucketList.size() - 2;; --i) { 1029 Bucket<V> singleBucket = bucketList.get(i); 1030 if (singleBucket.labelType != LabelType.NORMAL) { 1031 // There is no single-character bucket since the last 1032 // underflow or inflow label. 1033 break; 1034 } 1035 if (singleBucket.displayBucket == null && 1036 !hasMultiplePrimaryWeights(collatorPrimaryOnly, variableTop, singleBucket.lowerBoundary)) { 1037 // Add an invisible bucket that redirects strings greater than the expansion 1038 // to the previous single-character bucket. 1039 // For example, after ... Q R S Sch we add Sch\uFFFF->S 1040 // and after ... Q R S Sch Sch\uFFFF St we add St\uFFFF->S. 1041 bucket = new Bucket<V>("", current + "\uFFFF", LabelType.NORMAL); 1042 bucket.displayBucket = singleBucket; 1043 bucketList.add(bucket); 1044 hasInvisibleBuckets = true; 1045 break; 1046 } 1047 } 1048 } 1049 } 1050 if (bucketList.size() == 1) { 1051 // No real labels, show only the underflow label. 1052 return new BucketList<V>(bucketList, bucketList); 1053 } 1054 // overflow bucket 1055 bucketList.add(new Bucket<V>(getOverflowLabel(), scriptUpperBoundary, LabelType.OVERFLOW)); // final 1056 1057 if (hasPinyin) { 1058 // Redirect Pinyin buckets. 1059 Bucket<V> asciiBucket = null; 1060 for (int i = 0; i < 26; ++i) { 1061 if (asciiBuckets[i] != null) { 1062 asciiBucket = asciiBuckets[i]; 1063 } 1064 if (pinyinBuckets[i] != null && asciiBucket != null) { 1065 pinyinBuckets[i].displayBucket = asciiBucket; 1066 hasInvisibleBuckets = true; 1067 } 1068 } 1069 } 1070 1071 if (!hasInvisibleBuckets) { 1072 return new BucketList<V>(bucketList, bucketList); 1073 } 1074 // Merge inflow buckets that are visually adjacent. 1075 // Iterate backwards: Merge inflow into overflow rather than the other way around. 1076 int i = bucketList.size() - 1; 1077 Bucket<V> nextBucket = bucketList.get(i); 1078 while (--i > 0) { 1079 Bucket<V> bucket = bucketList.get(i); 1080 if (bucket.displayBucket != null) { 1081 continue; // skip invisible buckets 1082 } 1083 if (bucket.labelType == LabelType.INFLOW) { 1084 if (nextBucket.labelType != LabelType.NORMAL) { 1085 bucket.displayBucket = nextBucket; 1086 continue; 1087 } 1088 } 1089 nextBucket = bucket; 1090 } 1091 1092 ArrayList<Bucket<V>> publicBucketList = new ArrayList<Bucket<V>>(); 1093 for (Bucket<V> bucket : bucketList) { 1094 if (bucket.displayBucket == null) { 1095 publicBucketList.add(bucket); 1096 } 1097 } 1098 return new BucketList<V>(bucketList, publicBucketList); 1099 } 1100 1101 private static class BucketList<V> implements Iterable<Bucket<V>> { 1102 private final ArrayList<Bucket<V>> bucketList; 1103 private final List<Bucket<V>> immutableVisibleList; 1104 1105 private BucketList(ArrayList<Bucket<V>> bucketList, ArrayList<Bucket<V>> publicBucketList) { 1106 this.bucketList = bucketList; 1107 1108 int displayIndex = 0; 1109 for (Bucket<V> bucket : publicBucketList) { 1110 bucket.displayIndex = displayIndex++; 1111 } 1112 immutableVisibleList = Collections.unmodifiableList(publicBucketList); 1113 } 1114 1115 private int getBucketCount() { 1116 return immutableVisibleList.size(); 1117 } 1118 1119 private int getBucketIndex(CharSequence name, Collator collatorPrimaryOnly) { 1120 // binary search 1121 int start = 0; 1122 int limit = bucketList.size(); 1123 while ((start + 1) < limit) { 1124 int i = (start + limit) / 2; 1125 Bucket<V> bucket = bucketList.get(i); 1126 int nameVsBucket = collatorPrimaryOnly.compare(name, bucket.lowerBoundary); 1127 if (nameVsBucket < 0) { 1128 limit = i; 1129 } else { 1130 start = i; 1131 } 1132 } 1133 Bucket<V> bucket = bucketList.get(start); 1134 if (bucket.displayBucket != null) { 1135 bucket = bucket.displayBucket; 1136 } 1137 return bucket.displayIndex; 1138 } 1139 1140 /** 1141 * Private iterator over all the buckets, visible and invisible 1142 */ 1143 private Iterator<Bucket<V>> fullIterator() { 1144 return bucketList.iterator(); 1145 } 1146 1147 /** 1148 * Iterator over just the visible buckets. 1149 */ 1150 @Override 1151 public Iterator<Bucket<V>> iterator() { 1152 return immutableVisibleList.iterator(); // use immutable list to prevent remove(). 1153 } 1154 } 1155 1156 private static boolean hasMultiplePrimaryWeights( 1157 RuleBasedCollator coll, long variableTop, String s) { 1158 long[] ces = coll.internalGetCEs(s); 1159 boolean seenPrimary = false; 1160 for (int i = 0; i < ces.length; ++i) { 1161 long ce = ces[i]; 1162 long p = ce >>> 32; 1163 if (p > variableTop) { 1164 // not primary ignorable 1165 if (seenPrimary) { 1166 return true; 1167 } 1168 seenPrimary = true; 1169 } 1170 } 1171 return false; 1172 } 1173 1174 // TODO: Surely we have at least a ticket for porting these mask values to UCharacter.java?! 1175 private static final int GC_LU_MASK = 1 << UCharacter.UPPERCASE_LETTER; 1176 private static final int GC_LL_MASK = 1 << UCharacter.LOWERCASE_LETTER; 1177 private static final int GC_LT_MASK = 1 << UCharacter.TITLECASE_LETTER; 1178 private static final int GC_LM_MASK = 1 << UCharacter.MODIFIER_LETTER; 1179 private static final int GC_LO_MASK = 1 << UCharacter.OTHER_LETTER; 1180 private static final int GC_L_MASK = 1181 GC_LU_MASK|GC_LL_MASK|GC_LT_MASK|GC_LM_MASK|GC_LO_MASK; 1182 private static final int GC_CN_MASK = 1 << UCharacter.GENERAL_OTHER_TYPES; 1183 1184 /** 1185 * Return a list of the first character in each script. Only exposed for testing. 1186 * 1187 * @return list of first characters in each script 1188 * @deprecated This API is ICU internal, only for testing. 1189 * @hide original deprecated declaration 1190 * @hide draft / provisional / internal are hidden on Android 1191 */ 1192 @Deprecated 1193 public List<String> getFirstCharactersInScripts() { 1194 List<String> dest = new ArrayList<String>(200); 1195 // Fetch the script-first-primary contractions which are defined in the root collator. 1196 // They all start with U+FDD1. 1197 UnicodeSet set = new UnicodeSet(); 1198 collatorPrimaryOnly.internalAddContractions(0xFDD1, set); 1199 if (set.isEmpty()) { 1200 throw new UnsupportedOperationException( 1201 "AlphabeticIndex requires script-first-primary contractions"); 1202 } 1203 for (String boundary : set) { 1204 int gcMask = 1 << UCharacter.getType(boundary.codePointAt(1)); 1205 if ((gcMask & (GC_L_MASK | GC_CN_MASK)) == 0) { 1206 // Ignore boundaries for the special reordering groups. 1207 // Take only those for "real scripts" (where the sample character is a Letter, 1208 // and the one for unassigned implicit weights (Cn). 1209 continue; 1210 } 1211 dest.add(boundary); 1212 } 1213 return dest; 1214 } 1215} 1216