001 /* RuleBasedCollator.java -- Concrete Collator Class
002 Copyright (C) 1998, 1999, 2000, 2001, 2003, 2004, 2005 Free Software Foundation, Inc.
003
004 This file is part of GNU Classpath.
005
006 GNU Classpath is free software; you can redistribute it and/or modify
007 it under the terms of the GNU General Public License as published by
008 the Free Software Foundation; either version 2, or (at your option)
009 any later version.
010
011 GNU Classpath is distributed in the hope that it will be useful, but
012 WITHOUT ANY WARRANTY; without even the implied warranty of
013 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
014 General Public License for more details.
015
016 You should have received a copy of the GNU General Public License
017 along with GNU Classpath; see the file COPYING. If not, write to the
018 Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
019 02110-1301 USA.
020
021 Linking this library statically or dynamically with other modules is
022 making a combined work based on this library. Thus, the terms and
023 conditions of the GNU General Public License cover the whole
024 combination.
025
026 As a special exception, the copyright holders of this library give you
027 permission to link this library with independent modules to produce an
028 executable, regardless of the license terms of these independent
029 modules, and to copy and distribute the resulting executable under
030 terms of your choice, provided that you also meet, for each linked
031 independent module, the terms and conditions of the license of that
032 module. An independent module is a module which is not derived from
033 or based on this library. If you modify this library, you may extend
034 this exception to your version of the library, but you are not
035 obligated to do so. If you do not wish to do so, delete this
036 exception statement from your version. */
037
038
039 package java.text;
040
041 import gnu.classpath.NotImplementedException;
042
043 import java.util.ArrayList;
044 import java.util.HashMap;
045
046 /* Written using "Java Class Libraries", 2nd edition, plus online
047 * API docs for JDK 1.2 from http://www.javasoft.com.
048 * Status: Believed complete and correct
049 */
050
051 /**
052 * This class is a concrete subclass of <code>Collator</code> suitable
053 * for string collation in a wide variety of languages. An instance of
054 * this class is normally returned by the <code>getInstance</code> method
055 * of <code>Collator</code> with rules predefined for the requested
056 * locale. However, an instance of this class can be created manually
057 * with any desired rules.
058 * <p>
059 * Rules take the form of a <code>String</code> with the following syntax
060 * <ul>
061 * <li> Modifier: '@'</li>
062 * <li> Relation: '<' | ';' | ',' | '=' : <text></li>
063 * <li> Reset: '&' : <text></li>
064 * </ul>
065 * The modifier character indicates that accents sort backward as is the
066 * case with French. The modifier applies to all rules <b>after</b>
067 * the modifier but before the next primary sequence. If placed at the end
068 * of the sequence if applies to all unknown accented character.
069 * The relational operators specify how the text
070 * argument relates to the previous term. The relation characters have
071 * the following meanings:
072 * <ul>
073 * <li>'<' - The text argument is greater than the prior term at the primary
074 * difference level.</li>
075 * <li>';' - The text argument is greater than the prior term at the secondary
076 * difference level.</li>
077 * <li>',' - The text argument is greater than the prior term at the tertiary
078 * difference level.</li>
079 * <li>'=' - The text argument is equal to the prior term</li>
080 * </ul>
081 * <p>
082 * As for the text argument itself, this is any sequence of Unicode
083 * characters not in the following ranges: 0x0009-0x000D, 0x0020-0x002F,
084 * 0x003A-0x0040, 0x005B-0x0060, and 0x007B-0x007E. If these characters are
085 * desired, they must be enclosed in single quotes. If any whitespace is
086 * encountered, it is ignored. (For example, "a b" is equal to "ab").
087 * <p>
088 * The reset operation inserts the following rule at the point where the
089 * text argument to it exists in the previously declared rule string. This
090 * makes it easy to add new rules to an existing string by simply including
091 * them in a reset sequence at the end. Note that the text argument, or
092 * at least the first character of it, must be present somewhere in the
093 * previously declared rules in order to be inserted properly. If this
094 * is not satisfied, a <code>ParseException</code> will be thrown.
095 * <p>
096 * This system of configuring <code>RuleBasedCollator</code> is needlessly
097 * complex and the people at Taligent who developed it (along with the folks
098 * at Sun who accepted it into the Java standard library) deserve a slow
099 * and agonizing death.
100 * <p>
101 * Here are a couple of example of rule strings:
102 * <p>
103 * "< a < b < c" - This string says that a is greater than b which is
104 * greater than c, with all differences being primary differences.
105 * <p>
106 * "< a,A < b,B < c,C" - This string says that 'A' is greater than 'a' with
107 * a tertiary strength comparison. Both 'b' and 'B' are greater than 'a' and
108 * 'A' during a primary strength comparison. But 'B' is greater than 'b'
109 * under a tertiary strength comparison.
110 * <p>
111 * "< a < c & a < b " - This sequence is identical in function to the
112 * "< a < b < c" rule string above. The '&' reset symbol indicates that
113 * the rule "< b" is to be inserted after the text argument "a" in the
114 * previous rule string segment.
115 * <p>
116 * "< a < b & y < z" - This is an error. The character 'y' does not appear
117 * anywhere in the previous rule string segment so the rule following the
118 * reset rule cannot be inserted.
119 * <p>
120 * "< a & A @ < e & E < f& F" - This sequence is equivalent to the following
121 * "< a & A < E & e < f & F".
122 * <p>
123 * For a description of the various comparison strength types, see the
124 * documentation for the <code>Collator</code> class.
125 * <p>
126 * As an additional complication to this already overly complex rule scheme,
127 * if any characters precede the first rule, these characters are considered
128 * ignorable. They will be treated as if they did not exist during
129 * comparisons. For example, "- < a < b ..." would make '-' an ignorable
130 * character such that the strings "high-tech" and "hightech" would
131 * be considered identical.
132 * <p>
133 * A <code>ParseException</code> will be thrown for any of the following
134 * conditions:
135 * <ul>
136 * <li>Unquoted punctuation characters in a text argument.</li>
137 * <li>A relational or reset operator not followed by a text argument</li>
138 * <li>A reset operator where the text argument is not present in
139 * the previous rule string section.</li>
140 * </ul>
141 *
142 * @author Aaron M. Renn (arenn@urbanophile.com)
143 * @author Tom Tromey (tromey@cygnus.com)
144 * @author Guilhem Lavaux (guilhem@kaffe.org)
145 */
146 public class RuleBasedCollator extends Collator
147 {
148 /**
149 * This class describes what rank has a character (or a sequence of characters)
150 * in the lexicographic order. Each element in a rule has a collation element.
151 */
152 static final class CollationElement
153 {
154 final String key;
155 final int primary;
156 final short secondary;
157 final short tertiary;
158 final short equality;
159 final boolean ignore;
160 final String expansion;
161
162 CollationElement(String key, int primary, short secondary, short tertiary,
163 short equality, String expansion, boolean ignore)
164 {
165 this.key = key;
166 this.primary = primary;
167 this.secondary = secondary;
168 this.tertiary = tertiary;
169 this.equality = equality;
170 this.ignore = ignore;
171 this.expansion = expansion;
172 }
173
174 int getValue()
175 {
176 return (primary << 16) + (secondary << 8) + tertiary;
177 }
178 }
179
180 /**
181 * Basic collation instruction (internal format) to build the series of
182 * collation elements. It contains an instruction which specifies the new
183 * state of the generator. The sequence of instruction should not contain
184 * RESET (it is used by
185 * {@link #mergeRules(int,java.lang.String,java.util.ArrayList,java.util.ArrayList)})
186 * as a temporary state while merging two sets of instructions.
187 */
188 private static final class CollationSorter
189 {
190 static final int GREATERP = 0;
191 static final int GREATERS = 1;
192 static final int GREATERT = 2;
193 static final int EQUAL = 3;
194 static final int RESET = 4;
195 static final int INVERSE_SECONDARY = 5;
196
197 final int comparisonType;
198 final String textElement;
199 final int hashText;
200 final int offset;
201 final boolean ignore;
202
203 String expansionOrdering;
204
205 private CollationSorter(final int comparisonType, final String textElement,
206 final int offset, final boolean ignore)
207 {
208 this.comparisonType = comparisonType;
209 this.textElement = textElement;
210 this.offset = offset;
211 this.ignore = ignore;
212 hashText = textElement.hashCode();
213 }
214 }
215
216 /**
217 * This is the original rule string.
218 */
219 private String rules;
220
221 /**
222 * This is the table of collation element values
223 */
224 private CollationElement[] ce_table;
225
226 /**
227 * Quick-prefix finder.
228 */
229 HashMap<String,CollationElement> prefix_tree;
230
231 /**
232 * This is the value of the last sequence entered into
233 * <code>ce_table</code>. It is used to compute the
234 * ordering value of unspecified character.
235 */
236 private int last_primary_value;
237
238 /**
239 * This is the value of the last secondary sequence of the
240 * primary 0, entered into
241 * <code>ce_table</code>. It is used to compute the
242 * ordering value of an unspecified accented character.
243 */
244 private int last_tertiary_value;
245
246 /**
247 * This variable is true if accents need to be sorted
248 * in the other direction.
249 */
250 private boolean inverseAccentComparison;
251
252 /**
253 * This collation element is special to unknown sequence.
254 * The JDK uses it to mark and sort the characters which has
255 * no collation rules.
256 */
257 static final CollationElement SPECIAL_UNKNOWN_SEQ =
258 new CollationElement("", (short) 32767, (short) 0, (short) 0,
259 (short) 0, null, false);
260
261 /**
262 * This method initializes a new instance of <code>RuleBasedCollator</code>
263 * with the specified collation rules. Note that an application normally
264 * obtains an instance of <code>RuleBasedCollator</code> by calling the
265 * <code>getInstance</code> method of <code>Collator</code>. That method
266 * automatically loads the proper set of rules for the desired locale.
267 *
268 * @param rules The collation rule string.
269 *
270 * @exception ParseException If the rule string contains syntax errors.
271 */
272 public RuleBasedCollator(String rules) throws ParseException
273 {
274 if (rules.equals(""))
275 throw new ParseException("empty rule set", 0);
276
277 this.rules = rules;
278
279 buildCollationVector(parseString(rules));
280 buildPrefixAccess();
281 }
282
283 /**
284 * This method returns the number of common characters at the beginning
285 * of the string of the two parameters.
286 *
287 * @param prefix A string considered as a prefix to test against
288 * the other string.
289 * @param s A string to test the prefix against.
290 * @return The number of common characters.
291 */
292 static int findPrefixLength(String prefix, String s)
293 {
294 int index;
295 int len = prefix.length();
296
297 for (index = 0; index < len && index < s.length(); ++index)
298 {
299 if (prefix.charAt(index) != s.charAt(index))
300 return index;
301 }
302
303
304 return index;
305 }
306
307 /**
308 * Here we are merging two sets of sorting instructions: 'patch' into 'main'. This methods
309 * checks whether it is possible to find an anchor point for the rules to be merged and
310 * then insert them at that precise point.
311 *
312 * @param offset Offset in the string containing rules of the beginning of the rules
313 * being merged in.
314 * @param starter Text of the rules being merged.
315 * @param main Repository of all already parsed rules.
316 * @param patch Rules to be merged into the repository.
317 * @throws ParseException if it is impossible to find an anchor point for the new rules.
318 */
319 private void mergeRules(int offset, String starter, ArrayList<CollationSorter> main,
320 ArrayList<CollationSorter> patch)
321 throws ParseException
322 {
323 int insertion_point = -1;
324 int max_length = 0;
325
326 /* We must check that no rules conflict with another already present. If it
327 * is the case delete the old rule.
328 */
329
330 /* For the moment good old O(N^2) algorithm.
331 */
332 for (int i = 0; i < patch.size(); i++)
333 {
334 int j = 0;
335
336 while (j < main.size())
337 {
338 CollationSorter rule1 = patch.get(i);
339 CollationSorter rule2 = main.get(j);
340
341 if (rule1.textElement.equals(rule2.textElement))
342 main.remove(j);
343 else
344 j++;
345 }
346 }
347
348 // Find the insertion point... O(N)
349 for (int i = 0; i < main.size(); i++)
350 {
351 CollationSorter sorter = main.get(i);
352 int length = findPrefixLength(starter, sorter.textElement);
353
354 if (length > max_length)
355 {
356 max_length = length;
357 insertion_point = i+1;
358 }
359 }
360
361 if (insertion_point < 0)
362 throw new ParseException("no insertion point found for " + starter, offset);
363
364 if (max_length < starter.length())
365 {
366 /*
367 * We need to expand the first entry. It must be sorted
368 * like if it was the reference key itself (like the spec
369 * said. So the first entry is special: the element is
370 * replaced by the specified text element for the sorting.
371 * This text replace the old one for comparisons. However
372 * to preserve the behaviour we replace the first key (corresponding
373 * to the found prefix) by a new code rightly ordered in the
374 * sequence. The rest of the subsequence must be appended
375 * to the end of the sequence.
376 */
377 CollationSorter sorter = patch.get(0);
378
379 sorter.expansionOrdering = starter.substring(max_length); // Skip the first good prefix element
380
381 main.add(insertion_point, sorter);
382
383 /*
384 * This is a new set of rules. Append to the list.
385 */
386 patch.remove(0);
387 insertion_point++;
388 }
389
390 // Now insert all elements of patch at the insertion point.
391 for (int i = 0; i < patch.size(); i++)
392 main.add(i+insertion_point, patch.get(i));
393 }
394
395 /**
396 * This method parses a string and build a set of sorting instructions. The parsing
397 * may only be partial on the case the rules are to be merged sometime later.
398 *
399 * @param stop_on_reset If this parameter is true then the parser stops when it
400 * encounters a reset instruction. In the other case, it tries to parse the subrules
401 * and merged it in the same repository.
402 * @param v Output vector for the set of instructions.
403 * @param base_offset Offset in the string to begin parsing.
404 * @param rules Rules to be parsed.
405 * @return -1 if the parser reached the end of the string, an integer representing the
406 * offset in the string at which it stopped parsing.
407 * @throws ParseException if something turned wrong during the parsing. To get details
408 * decode the message.
409 */
410 private int subParseString(boolean stop_on_reset, ArrayList<CollationSorter> v,
411 int base_offset, String rules)
412 throws ParseException
413 {
414 boolean ignoreChars = (base_offset == 0);
415 int operator = -1;
416 StringBuilder sb = new StringBuilder();
417 boolean doubleQuote = false;
418 boolean eatingChars = false;
419 boolean nextIsModifier = false;
420 boolean isModifier = false;
421 int i;
422
423 main_parse_loop:
424 for (i = 0; i < rules.length(); i++)
425 {
426 char c = rules.charAt(i);
427 int type = -1;
428
429 if (!eatingChars &&
430 ((c >= 0x09 && c <= 0x0D) || (c == 0x20)))
431 continue;
432
433 isModifier = nextIsModifier;
434 nextIsModifier = false;
435
436 if (eatingChars && c != '\'')
437 {
438 doubleQuote = false;
439 sb.append(c);
440 continue;
441 }
442 if (doubleQuote && eatingChars)
443 {
444 sb.append(c);
445 doubleQuote = false;
446 continue;
447 }
448
449 switch (c)
450 {
451 case '!':
452 throw new ParseException
453 ("Modifier '!' is not yet supported by Classpath", i + base_offset);
454 case '<':
455 type = CollationSorter.GREATERP;
456 break;
457 case ';':
458 type = CollationSorter.GREATERS;
459 break;
460 case ',':
461 type = CollationSorter.GREATERT;
462 break;
463 case '=':
464 type = CollationSorter.EQUAL;
465 break;
466 case '\'':
467 eatingChars = !eatingChars;
468 doubleQuote = true;
469 break;
470 case '@':
471 if (ignoreChars)
472 throw new ParseException
473 ("comparison list has not yet been started. You may only use"
474 + "(<,;=&)", i + base_offset);
475 // Inverse the order of secondaries from now on.
476 nextIsModifier = true;
477 type = CollationSorter.INVERSE_SECONDARY;
478 break;
479 case '&':
480 type = CollationSorter.RESET;
481 if (stop_on_reset)
482 break main_parse_loop;
483 break;
484 default:
485 if (operator < 0)
486 throw new ParseException
487 ("operator missing at " + (i + base_offset), i + base_offset);
488 if (! eatingChars
489 && ((c >= 0x21 && c <= 0x2F)
490 || (c >= 0x3A && c <= 0x40)
491 || (c >= 0x5B && c <= 0x60)
492 || (c >= 0x7B && c <= 0x7E)))
493 throw new ParseException
494 ("unquoted punctuation character '" + c + "'", i + base_offset);
495
496 //type = ignoreChars ? CollationSorter.IGNORE : -1;
497 sb.append(c);
498 break;
499 }
500
501 if (type < 0)
502 continue;
503
504 if (operator < 0)
505 {
506 operator = type;
507 continue;
508 }
509
510 if (sb.length() == 0 && !isModifier)
511 throw new ParseException
512 ("text element empty at " + (i+base_offset), i+base_offset);
513
514 if (operator == CollationSorter.RESET)
515 {
516 /* Reposition in the sorting list at the position
517 * indicated by the text element.
518 */
519 String subrules = rules.substring(i);
520 ArrayList<CollationSorter> sorted_rules = new ArrayList<CollationSorter>();
521 int idx;
522
523 // Parse the subrules but do not iterate through all
524 // sublist. This is the privilege of the first call.
525 idx = subParseString(true, sorted_rules, base_offset+i, subrules);
526
527 // Merge new parsed rules into the list.
528 mergeRules(base_offset+i, sb.toString(), v, sorted_rules);
529 sb.setLength(0);
530
531 // Reset state to none.
532 operator = -1;
533 type = -1;
534 // We have found a new subrule at 'idx' but it has not been parsed.
535 if (idx >= 0)
536 {
537 i += idx-1;
538 continue main_parse_loop;
539 }
540 else
541 // No more rules.
542 break main_parse_loop;
543 }
544
545 String textElement = sb.toString();
546 if (operator == CollationSorter.GREATERP)
547 ignoreChars = false;
548 CollationSorter sorter = new CollationSorter(operator, textElement,
549 base_offset + rules.length(),
550 ignoreChars);
551 sb.setLength(0);
552
553 v.add(sorter);
554 operator = type;
555 }
556
557 if (operator >= 0)
558 {
559 int pos = rules.length() + base_offset;
560
561 if ((sb.length() != 0 && nextIsModifier)
562 || (sb.length() == 0 && !nextIsModifier && !eatingChars))
563 throw new ParseException("text element empty at " + pos, pos);
564
565 if (operator == CollationSorter.GREATERP)
566 ignoreChars = false;
567
568 CollationSorter sorter = new CollationSorter(operator, sb.toString(),
569 base_offset+pos, ignoreChars);
570 v.add(sorter);
571 }
572
573 if (i == rules.length())
574 return -1;
575 else
576 return i;
577 }
578
579 /**
580 * This method creates a copy of this object.
581 *
582 * @return A copy of this object.
583 */
584 public Object clone()
585 {
586 return super.clone();
587 }
588
589 /**
590 * This method completely parses a string 'rules' containing sorting rules.
591 *
592 * @param rules String containing the rules to be parsed.
593 * @return A set of sorting instructions stored in a Vector.
594 * @throws ParseException if something turned wrong during the parsing. To get details
595 * decode the message.
596 */
597 private ArrayList<CollationSorter> parseString(String rules)
598 throws ParseException
599 {
600 ArrayList<CollationSorter> v = new ArrayList<CollationSorter>();
601
602 // result of the first subParseString is not absolute (may be -1 or a
603 // positive integer). But we do not care.
604 subParseString(false, v, 0, rules);
605
606 return v;
607 }
608
609 /**
610 * This method uses the sorting instructions built by {@link #parseString}
611 * to build collation elements which can be directly used to sort strings.
612 *
613 * @param parsedElements Parsed instructions stored in a ArrayList.
614 * @throws ParseException if the order of the instructions are not valid.
615 */
616 private void buildCollationVector(ArrayList<CollationSorter> parsedElements)
617 throws ParseException
618 {
619 int primary_seq = 0;
620 int last_tertiary_seq = 0;
621 short secondary_seq = 0;
622 short tertiary_seq = 0;
623 short equality_seq = 0;
624 boolean inverseComparisons = false;
625 final boolean DECREASING = false;
626 final boolean INCREASING = true;
627 boolean secondaryType = INCREASING;
628 ArrayList<CollationElement> v = new ArrayList<CollationElement>();
629
630 // elts is completely sorted.
631 element_loop:
632 for (int i = 0; i < parsedElements.size(); i++)
633 {
634 CollationSorter elt = parsedElements.get(i);
635
636 switch (elt.comparisonType)
637 {
638 case CollationSorter.GREATERP:
639 primary_seq++;
640 if (inverseComparisons)
641 {
642 secondary_seq = Short.MAX_VALUE;
643 secondaryType = DECREASING;
644 }
645 else
646 {
647 secondary_seq = 0;
648 secondaryType = INCREASING;
649 }
650 tertiary_seq = 0;
651 equality_seq = 0;
652 inverseComparisons = false;
653 break;
654 case CollationSorter.GREATERS:
655 if (secondaryType == DECREASING)
656 secondary_seq--;
657 else
658 secondary_seq++;
659 tertiary_seq = 0;
660 equality_seq = 0;
661 break;
662 case CollationSorter.INVERSE_SECONDARY:
663 inverseComparisons = true;
664 continue element_loop;
665 case CollationSorter.GREATERT:
666 tertiary_seq++;
667 if (primary_seq == 0)
668 last_tertiary_seq = tertiary_seq;
669 equality_seq = 0;
670 break;
671 case CollationSorter.EQUAL:
672 equality_seq++;
673 break;
674 case CollationSorter.RESET:
675 throw new ParseException
676 ("Invalid reached state 'RESET'. Internal error", elt.offset);
677 default:
678 throw new ParseException
679 ("Invalid unknown state '" + elt.comparisonType + "'", elt.offset);
680 }
681
682 v.add(new CollationElement(elt.textElement, primary_seq,
683 secondary_seq, tertiary_seq,
684 equality_seq, elt.expansionOrdering, elt.ignore));
685 }
686
687 this.inverseAccentComparison = inverseComparisons;
688
689 ce_table = v.toArray(new CollationElement[v.size()]);
690
691 last_primary_value = primary_seq+1;
692 last_tertiary_value = last_tertiary_seq+1;
693 }
694
695 /**
696 * Build a tree where all keys are the texts of collation elements and data is
697 * the collation element itself. The tree is used when extracting all prefix
698 * for a given text.
699 */
700 private void buildPrefixAccess()
701 {
702 prefix_tree = new HashMap<String,CollationElement>();
703
704 for (int i = 0; i < ce_table.length; i++)
705 {
706 CollationElement e = ce_table[i];
707
708 prefix_tree.put(e.key, e);
709 }
710 }
711
712 /**
713 * This method returns an integer which indicates whether the first
714 * specified <code>String</code> is less than, greater than, or equal to
715 * the second. The value depends not only on the collation rules in
716 * effect, but also the strength and decomposition settings of this object.
717 *
718 * @param source The first <code>String</code> to compare.
719 * @param target A second <code>String</code> to compare to the first.
720 *
721 * @return A negative integer if source < target, a positive integer
722 * if source > target, or 0 if source == target.
723 */
724 public int compare(String source, String target)
725 {
726 CollationElementIterator cs, ct;
727 CollationElement ord1block = null;
728 CollationElement ord2block = null;
729 boolean advance_block_1 = true;
730 boolean advance_block_2 = true;
731
732 cs = getCollationElementIterator(source);
733 ct = getCollationElementIterator(target);
734
735 for(;;)
736 {
737 int ord1;
738 int ord2;
739
740 /*
741 * We have to check whether the characters are ignorable.
742 * If it is the case then forget them.
743 */
744 if (advance_block_1)
745 {
746 ord1block = cs.nextBlock();
747 if (ord1block != null && ord1block.ignore)
748 continue;
749 }
750
751 if (advance_block_2)
752 {
753 ord2block = ct.nextBlock();
754 if (ord2block != null && ord2block.ignore)
755 {
756 advance_block_1 = false;
757 continue;
758 }
759 }
760 else
761 advance_block_2 = true;
762
763 if (!advance_block_1)
764 advance_block_1 = true;
765
766 if (ord1block != null)
767 ord1 = ord1block.getValue();
768 else
769 {
770 if (ord2block == null)
771 return 0;
772 return -1;
773 }
774
775 if (ord2block == null)
776 return 1;
777
778 ord2 = ord2block.getValue();
779
780 // We know chars are totally equal, so skip
781 if (ord1 == ord2)
782 {
783 if (getStrength() == IDENTICAL)
784 if (!ord1block.key.equals(ord2block.key))
785 return ord1block.key.compareTo(ord2block.key);
786 continue;
787 }
788
789 // Check for primary strength differences
790 int prim1 = CollationElementIterator.primaryOrder(ord1);
791 int prim2 = CollationElementIterator.primaryOrder(ord2);
792
793 if (prim1 == 0 && getStrength() < TERTIARY)
794 {
795 advance_block_2 = false;
796 continue;
797 }
798 else if (prim2 == 0 && getStrength() < TERTIARY)
799 {
800 advance_block_1 = false;
801 continue;
802 }
803
804 if (prim1 < prim2)
805 return -1;
806 else if (prim1 > prim2)
807 return 1;
808 else if (getStrength() == PRIMARY)
809 continue;
810
811 // Check for secondary strength differences
812 int sec1 = CollationElementIterator.secondaryOrder(ord1);
813 int sec2 = CollationElementIterator.secondaryOrder(ord2);
814
815 if (sec1 < sec2)
816 return -1;
817 else if (sec1 > sec2)
818 return 1;
819 else if (getStrength() == SECONDARY)
820 continue;
821
822 // Check for tertiary differences
823 int tert1 = CollationElementIterator.tertiaryOrder(ord1);
824 int tert2 = CollationElementIterator.tertiaryOrder(ord2);
825
826 if (tert1 < tert2)
827 return -1;
828 else if (tert1 > tert2)
829 return 1;
830 else if (getStrength() == TERTIARY)
831 continue;
832
833 // Apparently JDK does this (at least for my test case).
834 return ord1block.key.compareTo(ord2block.key);
835 }
836 }
837
838 /**
839 * This method tests this object for equality against the specified
840 * object. This will be true if and only if the specified object is
841 * another reference to this object.
842 *
843 * @param obj The <code>Object</code> to compare against this object.
844 *
845 * @return <code>true</code> if the specified object is equal to this object,
846 * <code>false</code> otherwise.
847 */
848 public boolean equals(Object obj)
849 {
850 if (obj == this)
851 return true;
852 else
853 return false;
854 }
855
856 /**
857 * This method builds a default collation element without invoking
858 * the database created from the rules passed to the constructor.
859 *
860 * @param c Character which needs a collation element.
861 * @return A valid brand new CollationElement instance.
862 */
863 CollationElement getDefaultElement(char c)
864 {
865 int v;
866
867 // Preliminary support for generic accent sorting inversion (I don't know if all
868 // characters in the range should be sorted backward). This is the place
869 // to fix this if needed.
870 if (inverseAccentComparison && (c >= 0x02B9 && c <= 0x0361))
871 v = 0x0361 - ((int) c - 0x02B9);
872 else
873 v = (short) c;
874 return new CollationElement("" + c, last_primary_value + v,
875 (short) 0, (short) 0, (short) 0, null, false);
876 }
877
878 /**
879 * This method builds a default collation element for an accented character
880 * without invoking the database created from the rules passed to the constructor.
881 *
882 * @param c Character which needs a collation element.
883 * @return A valid brand new CollationElement instance.
884 */
885 CollationElement getDefaultAccentedElement(char c)
886 {
887 int v;
888
889 // Preliminary support for generic accent sorting inversion (I don't know if all
890 // characters in the range should be sorted backward). This is the place
891 // to fix this if needed.
892 if (inverseAccentComparison && (c >= 0x02B9 && c <= 0x0361))
893 v = 0x0361 - ((int) c - 0x02B9);
894 else
895 v = (short) c;
896 return new CollationElement("" + c, (short) 0,
897 (short) 0, (short) (last_tertiary_value + v), (short) 0, null, false);
898 }
899
900 /**
901 * This method returns an instance for <code>CollationElementIterator</code>
902 * for the specified <code>String</code> under the collation rules for this
903 * object.
904 *
905 * @param source The <code>String</code> to return the
906 * <code>CollationElementIterator</code> instance for.
907 *
908 * @return A <code>CollationElementIterator</code> for the specified
909 * <code>String</code>.
910 */
911 public CollationElementIterator getCollationElementIterator(String source)
912 {
913 return new CollationElementIterator(this, source);
914 }
915
916 /**
917 * This method returns an instance of <code>CollationElementIterator</code>
918 * for the <code>String</code> represented by the specified
919 * <code>CharacterIterator</code>.
920 *
921 * @param source The <code>CharacterIterator</code> with the desired <code>String</code>.
922 *
923 * @return A <code>CollationElementIterator</code> for the specified <code>String</code>.
924 */
925 public CollationElementIterator getCollationElementIterator(CharacterIterator source)
926 {
927 return new CollationElementIterator(this, source);
928 }
929
930 /**
931 * This method returns an instance of <code>CollationKey</code> for the
932 * specified <code>String</code>. The object returned will have a
933 * more efficient mechanism for its comparison function that could
934 * provide speed benefits if multiple comparisons are performed, such
935 * as during a sort.
936 *
937 * @param source The <code>String</code> to create a <code>CollationKey</code> for.
938 *
939 * @return A <code>CollationKey</code> for the specified <code>String</code>.
940 */
941 public CollationKey getCollationKey(String source)
942 {
943 CollationElementIterator cei = getCollationElementIterator(source);
944 ArrayList<Integer> vect = new ArrayList<Integer>();
945
946 int ord = cei.next();
947 cei.reset(); //set to start of string
948
949 while (ord != CollationElementIterator.NULLORDER)
950 {
951 // If the primary order is null, it means this is an ignorable
952 // character.
953 if (CollationElementIterator.primaryOrder(ord) == 0)
954 {
955 ord = cei.next();
956 continue;
957 }
958 switch (getStrength())
959 {
960 case PRIMARY:
961 ord = CollationElementIterator.primaryOrder(ord);
962 break;
963
964 case SECONDARY:
965 ord = CollationElementIterator.primaryOrder(ord) << 8;
966 ord |= CollationElementIterator.secondaryOrder(ord);
967
968 default:
969 break;
970 }
971
972 vect.add(Integer.valueOf(ord));
973 ord = cei.next(); //increment to next key
974 }
975
976 Integer[] objarr = vect.toArray(new Integer[vect.size()]);
977 byte[] key = new byte[objarr.length * 4];
978
979 for (int i = 0; i < objarr.length; i++)
980 {
981 int j = objarr[i].intValue();
982 key [i * 4] = (byte) ((j & 0xFF000000) >> 24);
983 key [i * 4 + 1] = (byte) ((j & 0x00FF0000) >> 16);
984 key [i * 4 + 2] = (byte) ((j & 0x0000FF00) >> 8);
985 key [i * 4 + 3] = (byte) (j & 0x000000FF);
986 }
987
988 return new CollationKey(this, source, key);
989 }
990
991 /**
992 * This method returns a <code>String</code> containing the collation rules
993 * for this object.
994 *
995 * @return The collation rules for this object.
996 */
997 public String getRules()
998 {
999 return rules;
1000 }
1001
1002 /**
1003 * This method returns a hash value for this object.
1004 *
1005 * @return A hash value for this object.
1006 */
1007 public int hashCode()
1008 {
1009 return System.identityHashCode(this);
1010 }
1011 }