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gerrit-public.fairphone.software / platform / libcore / 319a3b994703aac84df7bcde272adfcb3cdbbbf0 / . / jdk / src / share / classes / sun / text / normalizer / UnicodeSet.java
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J. Duke319a3b92007-12-01 00:00:00 +0000[diff] [blame^]1/*
2 * Portions Copyright 2005-2006 Sun Microsystems, Inc. All Rights Reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation. Sun designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Sun in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
22 * CA 95054 USA or visit www.sun.com if you need additional information or
23 * have any questions.
24 */
25
26/*
27 *******************************************************************************
28 * (C) Copyright IBM Corp. 1996-2005 - All Rights Reserved *
29 * *
30 * The original version of this source code and documentation is copyrighted *
31 * and owned by IBM, These materials are provided under terms of a License *
32 * Agreement between IBM and Sun. This technology is protected by multiple *
33 * US and International patents. This notice and attribution to IBM may not *
34 * to removed. *
35 *******************************************************************************
36 */
37
38package sun.text.normalizer;
39
40import java.text.ParsePosition;
41import java.util.Map;
42import java.util.HashMap;
43import java.util.TreeSet;
44import java.util.Iterator;
45import java.util.Collection;
46
47/**
48 * A mutable set of Unicode characters and multicharacter strings. Objects of this class
49 * represent <em>character classes</em> used in regular expressions.
50 * A character specifies a subset of Unicode code points. Legal
51 * code points are U+0000 to U+10FFFF, inclusive.
52 *
53 * <p>The UnicodeSet class is not designed to be subclassed.
54 *
55 * <p><code>UnicodeSet</code> supports two APIs. The first is the
56 * <em>operand</em> API that allows the caller to modify the value of
57 * a <code>UnicodeSet</code> object. It conforms to Java 2's
58 * <code>java.util.Set</code> interface, although
59 * <code>UnicodeSet</code> does not actually implement that
60 * interface. All methods of <code>Set</code> are supported, with the
61 * modification that they take a character range or single character
62 * instead of an <code>Object</code>, and they take a
63 * <code>UnicodeSet</code> instead of a <code>Collection</code>. The
64 * operand API may be thought of in terms of boolean logic: a boolean
65 * OR is implemented by <code>add</code>, a boolean AND is implemented
66 * by <code>retain</code>, a boolean XOR is implemented by
67 * <code>complement</code> taking an argument, and a boolean NOT is
68 * implemented by <code>complement</code> with no argument. In terms
69 * of traditional set theory function names, <code>add</code> is a
70 * union, <code>retain</code> is an intersection, <code>remove</code>
71 * is an asymmetric difference, and <code>complement</code> with no
72 * argument is a set complement with respect to the superset range
73 * <code>MIN_VALUE-MAX_VALUE</code>
74 *
75 * <p>The second API is the
76 * <code>applyPattern()</code>/<code>toPattern()</code> API from the
77 * <code>java.text.Format</code>-derived classes. Unlike the
78 * methods that add characters, add categories, and control the logic
79 * of the set, the method <code>applyPattern()</code> sets all
80 * attributes of a <code>UnicodeSet</code> at once, based on a
81 * string pattern.
82 *
83 * <p><b>Pattern syntax</b></p>
84 *
85 * Patterns are accepted by the constructors and the
86 * <code>applyPattern()</code> methods and returned by the
87 * <code>toPattern()</code> method. These patterns follow a syntax
88 * similar to that employed by version 8 regular expression character
89 * classes. Here are some simple examples:
90 *
91 * <blockquote>
92 * <table>
93 * <tr align="top">
94 * <td nowrap valign="top" align="left"><code>[]</code></td>
95 * <td valign="top">No characters</td>
96 * </tr><tr align="top">
97 * <td nowrap valign="top" align="left"><code>[a]</code></td>
98 * <td valign="top">The character 'a'</td>
99 * </tr><tr align="top">
100 * <td nowrap valign="top" align="left"><code>[ae]</code></td>
101 * <td valign="top">The characters 'a' and 'e'</td>
102 * </tr>
103 * <tr>
104 * <td nowrap valign="top" align="left"><code>[a-e]</code></td>
105 * <td valign="top">The characters 'a' through 'e' inclusive, in Unicode code
106 * point order</td>
107 * </tr>
108 * <tr>
109 * <td nowrap valign="top" align="left"><code>[\\u4E01]</code></td>
110 * <td valign="top">The character U+4E01</td>
111 * </tr>
112 * <tr>
113 * <td nowrap valign="top" align="left"><code>[a{ab}{ac}]</code></td>
114 * <td valign="top">The character 'a' and the multicharacter strings &quot;ab&quot; and
115 * &quot;ac&quot;</td>
116 * </tr>
117 * <tr>
118 * <td nowrap valign="top" align="left"><code>[\p{Lu}]</code></td>
119 * <td valign="top">All characters in the general category Uppercase Letter</td>
120 * </tr>
121 * </table>
122 * </blockquote>
123 *
124 * Any character may be preceded by a backslash in order to remove any special
125 * meaning. White space characters, as defined by UCharacterProperty.isRuleWhiteSpace(), are
126 * ignored, unless they are escaped.
127 *
128 * <p>Property patterns specify a set of characters having a certain
129 * property as defined by the Unicode standard. Both the POSIX-like
130 * "[:Lu:]" and the Perl-like syntax "\p{Lu}" are recognized. For a
131 * complete list of supported property patterns, see the User's Guide
132 * for UnicodeSet at
133 * <a href="http://oss.software.ibm.com/icu/userguide/unicodeSet.html">
134 * http://oss.software.ibm.com/icu/userguide/unicodeSet.html</a>.
135 * Actual determination of property data is defined by the underlying
136 * Unicode database as implemented by UCharacter.
137 *
138 * <p>Patterns specify individual characters, ranges of characters, and
139 * Unicode property sets. When elements are concatenated, they
140 * specify their union. To complement a set, place a '^' immediately
141 * after the opening '['. Property patterns are inverted by modifying
142 * their delimiters; "[:^foo]" and "\P{foo}". In any other location,
143 * '^' has no special meaning.
144 *
145 * <p>Ranges are indicated by placing two a '-' between two
146 * characters, as in "a-z". This specifies the range of all
147 * characters from the left to the right, in Unicode order. If the
148 * left character is greater than or equal to the
149 * right character it is a syntax error. If a '-' occurs as the first
150 * character after the opening '[' or '[^', or if it occurs as the
151 * last character before the closing ']', then it is taken as a
152 * literal. Thus "[a\\-b]", "[-ab]", and "[ab-]" all indicate the same
153 * set of three characters, 'a', 'b', and '-'.
154 *
155 * <p>Sets may be intersected using the '&' operator or the asymmetric
156 * set difference may be taken using the '-' operator, for example,
157 * "[[:L:]&[\\u0000-\\u0FFF]]" indicates the set of all Unicode letters
158 * with values less than 4096. Operators ('&' and '|') have equal
159 * precedence and bind left-to-right. Thus
160 * "[[:L:]-[a-z]-[\\u0100-\\u01FF]]" is equivalent to
161 * "[[[:L:]-[a-z]]-[\\u0100-\\u01FF]]". This only really matters for
162 * difference; intersection is commutative.
163 *
164 * <table>
165 * <tr valign=top><td nowrap><code>[a]</code><td>The set containing 'a'
166 * <tr valign=top><td nowrap><code>[a-z]</code><td>The set containing 'a'
167 * through 'z' and all letters in between, in Unicode order
168 * <tr valign=top><td nowrap><code>[^a-z]</code><td>The set containing
169 * all characters but 'a' through 'z',
170 * that is, U+0000 through 'a'-1 and 'z'+1 through U+10FFFF
171 * <tr valign=top><td nowrap><code>[[<em>pat1</em>][<em>pat2</em>]]</code>
172 * <td>The union of sets specified by <em>pat1</em> and <em>pat2</em>
173 * <tr valign=top><td nowrap><code>[[<em>pat1</em>]&[<em>pat2</em>]]</code>
174 * <td>The intersection of sets specified by <em>pat1</em> and <em>pat2</em>
175 * <tr valign=top><td nowrap><code>[[<em>pat1</em>]-[<em>pat2</em>]]</code>
176 * <td>The asymmetric difference of sets specified by <em>pat1</em> and
177 * <em>pat2</em>
178 * <tr valign=top><td nowrap><code>[:Lu:] or \p{Lu}</code>
179 * <td>The set of characters having the specified
180 * Unicode property; in
181 * this case, Unicode uppercase letters
182 * <tr valign=top><td nowrap><code>[:^Lu:] or \P{Lu}</code>
183 * <td>The set of characters <em>not</em> having the given
184 * Unicode property
185 * </table>
186 *
187 * <p><b>Warning</b>: you cannot add an empty string ("") to a UnicodeSet.</p>
188 *
189 * <p><b>Formal syntax</b></p>
190 *
191 * <blockquote>
192 * <table>
193 * <tr align="top">
194 * <td nowrap valign="top" align="right"><code>pattern :=&nbsp; </code></td>
195 * <td valign="top"><code>('[' '^'? item* ']') |
196 * property</code></td>
197 * </tr>
198 * <tr align="top">
199 * <td nowrap valign="top" align="right"><code>item :=&nbsp; </code></td>
200 * <td valign="top"><code>char | (char '-' char) | pattern-expr<br>
201 * </code></td>
202 * </tr>
203 * <tr align="top">
204 * <td nowrap valign="top" align="right"><code>pattern-expr :=&nbsp; </code></td>
205 * <td valign="top"><code>pattern | pattern-expr pattern |
206 * pattern-expr op pattern<br>
207 * </code></td>
208 * </tr>
209 * <tr align="top">
210 * <td nowrap valign="top" align="right"><code>op :=&nbsp; </code></td>
211 * <td valign="top"><code>'&amp;' | '-'<br>
212 * </code></td>
213 * </tr>
214 * <tr align="top">
215 * <td nowrap valign="top" align="right"><code>special :=&nbsp; </code></td>
216 * <td valign="top"><code>'[' | ']' | '-'<br>
217 * </code></td>
218 * </tr>
219 * <tr align="top">
220 * <td nowrap valign="top" align="right"><code>char :=&nbsp; </code></td>
221 * <td valign="top"><em>any character that is not</em><code> special<br>
222 * | ('\\' </code><em>any character</em><code>)<br>
223 * | ('&#92;u' hex hex hex hex)<br>
224 * </code></td>
225 * </tr>
226 * <tr align="top">
227 * <td nowrap valign="top" align="right"><code>hex :=&nbsp; </code></td>
228 * <td valign="top"><em>any character for which
229 * </em><code>Character.digit(c, 16)</code><em>
230 * returns a non-negative result</em></td>
231 * </tr>
232 * <tr>
233 * <td nowrap valign="top" align="right"><code>property :=&nbsp; </code></td>
234 * <td valign="top"><em>a Unicode property set pattern</td>
235 * </tr>
236 * </table>
237 * <br>
238 * <table border="1">
239 * <tr>
240 * <td>Legend: <table>
241 * <tr>
242 * <td nowrap valign="top"><code>a := b</code></td>
243 * <td width="20" valign="top">&nbsp; </td>
244 * <td valign="top"><code>a</code> may be replaced by <code>b</code> </td>
245 * </tr>
246 * <tr>
247 * <td nowrap valign="top"><code>a?</code></td>
248 * <td valign="top"></td>
249 * <td valign="top">zero or one instance of <code>a</code><br>
250 * </td>
251 * </tr>
252 * <tr>
253 * <td nowrap valign="top"><code>a*</code></td>
254 * <td valign="top"></td>
255 * <td valign="top">one or more instances of <code>a</code><br>
256 * </td>
257 * </tr>
258 * <tr>
259 * <td nowrap valign="top"><code>a | b</code></td>
260 * <td valign="top"></td>
261 * <td valign="top">either <code>a</code> or <code>b</code><br>
262 * </td>
263 * </tr>
264 * <tr>
265 * <td nowrap valign="top"><code>'a'</code></td>
266 * <td valign="top"></td>
267 * <td valign="top">the literal string between the quotes </td>
268 * </tr>
269 * </table>
270 * </td>
271 * </tr>
272 * </table>
273 * </blockquote>
274 *
275 * @author Alan Liu
276 * @stable ICU 2.0
277 */
278public class UnicodeSet implements UnicodeMatcher {
279
280 private static final int LOW = 0x000000; // LOW <= all valid values. ZERO for codepoints
281 private static final int HIGH = 0x110000; // HIGH > all valid values. 10000 for code units.
282 // 110000 for codepoints
283
284 /**
285 * Minimum value that can be stored in a UnicodeSet.
286 * @stable ICU 2.0
287 */
288 public static final int MIN_VALUE = LOW;
289
290 /**
291 * Maximum value that can be stored in a UnicodeSet.
292 * @stable ICU 2.0
293 */
294 public static final int MAX_VALUE = HIGH - 1;
295
296 private int len; // length used; list may be longer to minimize reallocs
297 private int[] list; // MUST be terminated with HIGH
298 private int[] rangeList; // internal buffer
299 private int[] buffer; // internal buffer
300
301 // NOTE: normally the field should be of type SortedSet; but that is missing a public clone!!
302 // is not private so that UnicodeSetIterator can get access
303 TreeSet strings = new TreeSet();
304
305 /**
306 * The pattern representation of this set. This may not be the
307 * most economical pattern. It is the pattern supplied to
308 * applyPattern(), with variables substituted and whitespace
309 * removed. For sets constructed without applyPattern(), or
310 * modified using the non-pattern API, this string will be null,
311 * indicating that toPattern() must generate a pattern
312 * representation from the inversion list.
313 */
314 private String pat = null;
315
316 private static final int START_EXTRA = 16; // initial storage. Must be >= 0
317 private static final int GROW_EXTRA = START_EXTRA; // extra amount for growth. Must be >= 0
318
319 /**
320 * A set of all characters _except_ the second through last characters of
321 * certain ranges. These ranges are ranges of characters whose
322 * properties are all exactly alike, e.g. CJK Ideographs from
323 * U+4E00 to U+9FA5.
324 */
325 private static UnicodeSet INCLUSIONS = null;
326
327 //----------------------------------------------------------------
328 // Public API
329 //----------------------------------------------------------------
330
331 /**
332 * Constructs an empty set.
333 * @stable ICU 2.0
334 */
335 public UnicodeSet() {
336 list = new int[1 + START_EXTRA];
337 list[len++] = HIGH;
338 }
339
340 /**
341 * Constructs a set containing the given range. If <code>end >
342 * start</code> then an empty set is created.
343 *
344 * @param start first character, inclusive, of range
345 * @param end last character, inclusive, of range
346 * @stable ICU 2.0
347 */
348 public UnicodeSet(int start, int end) {
349 this();
350 complement(start, end);
351 }
352
353 /**
354 * Constructs a set from the given pattern. See the class description
355 * for the syntax of the pattern language. Whitespace is ignored.
356 * @param pattern a string specifying what characters are in the set
357 * @exception java.lang.IllegalArgumentException if the pattern contains
358 * a syntax error.
359 * @stable ICU 2.0
360 */
361 public UnicodeSet(String pattern) {
362 this();
363 applyPattern(pattern, null, null, IGNORE_SPACE);
364 }
365
366 /**
367 * Make this object represent the same set as <code>other</code>.
368 * @param other a <code>UnicodeSet</code> whose value will be
369 * copied to this object
370 * @stable ICU 2.0
371 */
372 public UnicodeSet set(UnicodeSet other) {
373 list = (int[]) other.list.clone();
374 len = other.len;
375 pat = other.pat;
376 strings = (TreeSet)other.strings.clone();
377 return this;
378 }
379
380 /**
381 * Modifies this set to represent the set specified by the given pattern.
382 * See the class description for the syntax of the pattern language.
383 * Whitespace is ignored.
384 * @param pattern a string specifying what characters are in the set
385 * @exception java.lang.IllegalArgumentException if the pattern
386 * contains a syntax error.
387 * @stable ICU 2.0
388 */
389 public final UnicodeSet applyPattern(String pattern) {
390 return applyPattern(pattern, null, null, IGNORE_SPACE);
391 }
392
393 /**
394 * Append the <code>toPattern()</code> representation of a
395 * string to the given <code>StringBuffer</code>.
396 */
397 private static void _appendToPat(StringBuffer buf, String s, boolean escapeUnprintable) {
398 for (int i = 0; i < s.length(); i += UTF16.getCharCount(i)) {
399 _appendToPat(buf, UTF16.charAt(s, i), escapeUnprintable);
400 }
401 }
402
403 /**
404 * Append the <code>toPattern()</code> representation of a
405 * character to the given <code>StringBuffer</code>.
406 */
407 private static void _appendToPat(StringBuffer buf, int c, boolean escapeUnprintable) {
408 if (escapeUnprintable && Utility.isUnprintable(c)) {
409 // Use hex escape notation (<backslash>uxxxx or <backslash>Uxxxxxxxx) for anything
410 // unprintable
411 if (Utility.escapeUnprintable(buf, c)) {
412 return;
413 }
414 }
415 // Okay to let ':' pass through
416 switch (c) {
417 case '[': // SET_OPEN:
418 case ']': // SET_CLOSE:
419 case '-': // HYPHEN:
420 case '^': // COMPLEMENT:
421 case '&': // INTERSECTION:
422 case '\\': //BACKSLASH:
423 case '{':
424 case '}':
425 case '$':
426 case ':':
427 buf.append('\\');
428 break;
429 default:
430 // Escape whitespace
431 if (UCharacterProperty.isRuleWhiteSpace(c)) {
432 buf.append('\\');
433 }
434 break;
435 }
436 UTF16.append(buf, c);
437 }
438
439 /**
440 * Append a string representation of this set to result. This will be
441 * a cleaned version of the string passed to applyPattern(), if there
442 * is one. Otherwise it will be generated.
443 */
444 private StringBuffer _toPattern(StringBuffer result,
445 boolean escapeUnprintable) {
446 if (pat != null) {
447 int i;
448 int backslashCount = 0;
449 for (i=0; i<pat.length(); ) {
450 int c = UTF16.charAt(pat, i);
451 i += UTF16.getCharCount(c);
452 if (escapeUnprintable && Utility.isUnprintable(c)) {
453 // If the unprintable character is preceded by an odd
454 // number of backslashes, then it has been escaped.
455 // Before unescaping it, we delete the final
456 // backslash.
457 if ((backslashCount % 2) == 1) {
458 result.setLength(result.length() - 1);
459 }
460 Utility.escapeUnprintable(result, c);
461 backslashCount = 0;
462 } else {
463 UTF16.append(result, c);
464 if (c == '\\') {
465 ++backslashCount;
466 } else {
467 backslashCount = 0;
468 }
469 }
470 }
471 return result;
472 }
473
474 return _generatePattern(result, escapeUnprintable);
475 }
476
477 /**
478 * Generate and append a string representation of this set to result.
479 * This does not use this.pat, the cleaned up copy of the string
480 * passed to applyPattern().
481 * @stable ICU 2.0
482 */
483 public StringBuffer _generatePattern(StringBuffer result,
484 boolean escapeUnprintable) {
485 result.append('[');
486
487 int count = getRangeCount();
488
489 // If the set contains at least 2 intervals and includes both
490 // MIN_VALUE and MAX_VALUE, then the inverse representation will
491 // be more economical.
492 if (count > 1 &&
493 getRangeStart(0) == MIN_VALUE &&
494 getRangeEnd(count-1) == MAX_VALUE) {
495
496 // Emit the inverse
497 result.append('^');
498
499 for (int i = 1; i < count; ++i) {
500 int start = getRangeEnd(i-1)+1;
501 int end = getRangeStart(i)-1;
502 _appendToPat(result, start, escapeUnprintable);
503 if (start != end) {
504 if ((start+1) != end) {
505 result.append('-');
506 }
507 _appendToPat(result, end, escapeUnprintable);
508 }
509 }
510 }
511
512 // Default; emit the ranges as pairs
513 else {
514 for (int i = 0; i < count; ++i) {
515 int start = getRangeStart(i);
516 int end = getRangeEnd(i);
517 _appendToPat(result, start, escapeUnprintable);
518 if (start != end) {
519 if ((start+1) != end) {
520 result.append('-');
521 }
522 _appendToPat(result, end, escapeUnprintable);
523 }
524 }
525 }
526
527 if (strings.size() > 0) {
528 Iterator it = strings.iterator();
529 while (it.hasNext()) {
530 result.append('{');
531 _appendToPat(result, (String) it.next(), escapeUnprintable);
532 result.append('}');
533 }
534 }
535 return result.append(']');
536 }
537
538 /**
539 * Adds the specified range to this set if it is not already
540 * present. If this set already contains the specified range,
541 * the call leaves this set unchanged. If <code>end > start</code>
542 * then an empty range is added, leaving the set unchanged.
543 *
544 * @param start first character, inclusive, of range to be added
545 * to this set.
546 * @param end last character, inclusive, of range to be added
547 * to this set.
548 * @stable ICU 2.0
549 */
550 public UnicodeSet add(int start, int end) {
551 if (start < MIN_VALUE || start > MAX_VALUE) {
552 throw new IllegalArgumentException("Invalid code point U+" + Utility.hex(start, 6));
553 }
554 if (end < MIN_VALUE || end > MAX_VALUE) {
555 throw new IllegalArgumentException("Invalid code point U+" + Utility.hex(end, 6));
556 }
557 if (start < end) {
558 add(range(start, end), 2, 0);
559 } else if (start == end) {
560 add(start);
561 }
562 return this;
563 }
564
565 /**
566 * Adds the specified character to this set if it is not already
567 * present. If this set already contains the specified character,
568 * the call leaves this set unchanged.
569 * @stable ICU 2.0
570 */
571 public final UnicodeSet add(int c) {
572 if (c < MIN_VALUE || c > MAX_VALUE) {
573 throw new IllegalArgumentException("Invalid code point U+" + Utility.hex(c, 6));
574 }
575
576 // find smallest i such that c < list[i]
577 // if odd, then it is IN the set
578 // if even, then it is OUT of the set
579 int i = findCodePoint(c);
580
581 // already in set?
582 if ((i & 1) != 0) return this;
583
584 // HIGH is 0x110000
585 // assert(list[len-1] == HIGH);
586
587 // empty = [HIGH]
588 // [start_0, limit_0, start_1, limit_1, HIGH]
589
590 // [..., start_k-1, limit_k-1, start_k, limit_k, ..., HIGH]
591 // ^
592 // list[i]
593
594 // i == 0 means c is before the first range
595
596 if (c == list[i]-1) {
597 // c is before start of next range
598 list[i] = c;
599 // if we touched the HIGH mark, then add a new one
600 if (c == MAX_VALUE) {
601 ensureCapacity(len+1);
602 list[len++] = HIGH;
603 }
604 if (i > 0 && c == list[i-1]) {
605 // collapse adjacent ranges
606
607 // [..., start_k-1, c, c, limit_k, ..., HIGH]
608 // ^
609 // list[i]
610 System.arraycopy(list, i+1, list, i-1, len-i-1);
611 len -= 2;
612 }
613 }
614
615 else if (i > 0 && c == list[i-1]) {
616 // c is after end of prior range
617 list[i-1]++;
618 // no need to chcek for collapse here
619 }
620
621 else {
622 // At this point we know the new char is not adjacent to
623 // any existing ranges, and it is not 10FFFF.
624
625
626 // [..., start_k-1, limit_k-1, start_k, limit_k, ..., HIGH]
627 // ^
628 // list[i]
629
630 // [..., start_k-1, limit_k-1, c, c+1, start_k, limit_k, ..., HIGH]
631 // ^
632 // list[i]
633
634 // Don't use ensureCapacity() to save on copying.
635 // NOTE: This has no measurable impact on performance,
636 // but it might help in some usage patterns.
637 if (len+2 > list.length) {
638 int[] temp = new int[len + 2 + GROW_EXTRA];
639 if (i != 0) System.arraycopy(list, 0, temp, 0, i);
640 System.arraycopy(list, i, temp, i+2, len-i);
641 list = temp;
642 } else {
643 System.arraycopy(list, i, list, i+2, len-i);
644 }
645
646 list[i] = c;
647 list[i+1] = c+1;
648 len += 2;
649 }
650
651 pat = null;
652 return this;
653 }
654
655 /**
656 * Adds the specified multicharacter to this set if it is not already
657 * present. If this set already contains the multicharacter,
658 * the call leaves this set unchanged.
659 * Thus "ch" => {"ch"}
660 * <br><b>Warning: you cannot add an empty string ("") to a UnicodeSet.</b>
661 * @param s the source string
662 * @return this object, for chaining
663 * @stable ICU 2.0
664 */
665 public final UnicodeSet add(String s) {
666
667 int cp = getSingleCP(s);
668 if (cp < 0) {
669 strings.add(s);
670 pat = null;
671 } else {
672 add(cp, cp);
673 }
674 return this;
675 }
676
677 /**
678 * @return a code point IF the string consists of a single one.
679 * otherwise returns -1.
680 * @param string to test
681 */
682 private static int getSingleCP(String s) {
683 if (s.length() < 1) {
684 throw new IllegalArgumentException("Can't use zero-length strings in UnicodeSet");
685 }
686 if (s.length() > 2) return -1;
687 if (s.length() == 1) return s.charAt(0);
688
689 // at this point, len = 2
690 int cp = UTF16.charAt(s, 0);
691 if (cp > 0xFFFF) { // is surrogate pair
692 return cp;
693 }
694 return -1;
695 }
696
697 /**
698 * Complements the specified range in this set. Any character in
699 * the range will be removed if it is in this set, or will be
700 * added if it is not in this set. If <code>end > start</code>
701 * then an empty range is complemented, leaving the set unchanged.
702 *
703 * @param start first character, inclusive, of range to be removed
704 * from this set.
705 * @param end last character, inclusive, of range to be removed
706 * from this set.
707 * @stable ICU 2.0
708 */
709 public UnicodeSet complement(int start, int end) {
710 if (start < MIN_VALUE || start > MAX_VALUE) {
711 throw new IllegalArgumentException("Invalid code point U+" + Utility.hex(start, 6));
712 }
713 if (end < MIN_VALUE || end > MAX_VALUE) {
714 throw new IllegalArgumentException("Invalid code point U+" + Utility.hex(end, 6));
715 }
716 if (start <= end) {
717 xor(range(start, end), 2, 0);
718 }
719 pat = null;
720 return this;
721 }
722
723 /**
724 * This is equivalent to
725 * <code>complement(MIN_VALUE, MAX_VALUE)</code>.
726 * @stable ICU 2.0
727 */
728 public UnicodeSet complement() {
729 if (list[0] == LOW) {
730 System.arraycopy(list, 1, list, 0, len-1);
731 --len;
732 } else {
733 ensureCapacity(len+1);
734 System.arraycopy(list, 0, list, 1, len);
735 list[0] = LOW;
736 ++len;
737 }
738 pat = null;
739 return this;
740 }
741
742 /**
743 * Returns true if this set contains the given character.
744 * @param c character to be checked for containment
745 * @return true if the test condition is met
746 * @stable ICU 2.0
747 */
748 public boolean contains(int c) {
749 if (c < MIN_VALUE || c > MAX_VALUE) {
750 throw new IllegalArgumentException("Invalid code point U+" + Utility.hex(c, 6));
751 }
752
753 /*
754 // Set i to the index of the start item greater than ch
755 // We know we will terminate without length test!
756 int i = -1;
757 while (true) {
758 if (c < list[++i]) break;
759 }
760 */
761
762 int i = findCodePoint(c);
763
764 return ((i & 1) != 0); // return true if odd
765 }
766
767 /**
768 * Returns the smallest value i such that c < list[i]. Caller
769 * must ensure that c is a legal value or this method will enter
770 * an infinite loop. This method performs a binary search.
771 * @param c a character in the range MIN_VALUE..MAX_VALUE
772 * inclusive
773 * @return the smallest integer i in the range 0..len-1,
774 * inclusive, such that c < list[i]
775 */
776 private final int findCodePoint(int c) {
777 /* Examples:
778 findCodePoint(c)
779 set list[] c=0 1 3 4 7 8
780 === ============== ===========
781 [] [110000] 0 0 0 0 0 0
782 [\u0000-\u0003] [0, 4, 110000] 1 1 1 2 2 2
783 [\u0004-\u0007] [4, 8, 110000] 0 0 0 1 1 2
784 [:all:] [0, 110000] 1 1 1 1 1 1
785 */
786
787 // Return the smallest i such that c < list[i]. Assume
788 // list[len - 1] == HIGH and that c is legal (0..HIGH-1).
789 if (c < list[0]) return 0;
790 // High runner test. c is often after the last range, so an
791 // initial check for this condition pays off.
792 if (len >= 2 && c >= list[len-2]) return len-1;
793 int lo = 0;
794 int hi = len - 1;
795 // invariant: c >= list[lo]
796 // invariant: c < list[hi]
797 for (;;) {
798 int i = (lo + hi) >>> 1;
799 if (i == lo) return hi;
800 if (c < list[i]) {
801 hi = i;
802 } else {
803 lo = i;
804 }
805 }
806 }
807
808 /**
809 * Adds all of the elements in the specified set to this set if
810 * they're not already present. This operation effectively
811 * modifies this set so that its value is the <i>union</i> of the two
812 * sets. The behavior of this operation is unspecified if the specified
813 * collection is modified while the operation is in progress.
814 *
815 * @param c set whose elements are to be added to this set.
816 * @stable ICU 2.0
817 */
818 public UnicodeSet addAll(UnicodeSet c) {
819 add(c.list, c.len, 0);
820 strings.addAll(c.strings);
821 return this;
822 }
823
824 /**
825 * Retains only the elements in this set that are contained in the
826 * specified set. In other words, removes from this set all of
827 * its elements that are not contained in the specified set. This
828 * operation effectively modifies this set so that its value is
829 * the <i>intersection</i> of the two sets.
830 *
831 * @param c set that defines which elements this set will retain.
832 * @stable ICU 2.0
833 */
834 public UnicodeSet retainAll(UnicodeSet c) {
835 retain(c.list, c.len, 0);
836 strings.retainAll(c.strings);
837 return this;
838 }
839
840 /**
841 * Removes from this set all of its elements that are contained in the
842 * specified set. This operation effectively modifies this
843 * set so that its value is the <i>asymmetric set difference</i> of
844 * the two sets.
845 *
846 * @param c set that defines which elements will be removed from
847 * this set.
848 * @stable ICU 2.0
849 */
850 public UnicodeSet removeAll(UnicodeSet c) {
851 retain(c.list, c.len, 2);
852 strings.removeAll(c.strings);
853 return this;
854 }
855
856 /**
857 * Removes all of the elements from this set. This set will be
858 * empty after this call returns.
859 * @stable ICU 2.0
860 */
861 public UnicodeSet clear() {
862 list[0] = HIGH;
863 len = 1;
864 pat = null;
865 strings.clear();
866 return this;
867 }
868
869 /**
870 * Iteration method that returns the number of ranges contained in
871 * this set.
872 * @see #getRangeStart
873 * @see #getRangeEnd
874 * @stable ICU 2.0
875 */
876 public int getRangeCount() {
877 return len/2;
878 }
879
880 /**
881 * Iteration method that returns the first character in the
882 * specified range of this set.
883 * @exception ArrayIndexOutOfBoundsException if index is outside
884 * the range <code>0..getRangeCount()-1</code>
885 * @see #getRangeCount
886 * @see #getRangeEnd
887 * @stable ICU 2.0
888 */
889 public int getRangeStart(int index) {
890 return list[index*2];
891 }
892
893 /**
894 * Iteration method that returns the last character in the
895 * specified range of this set.
896 * @exception ArrayIndexOutOfBoundsException if index is outside
897 * the range <code>0..getRangeCount()-1</code>
898 * @see #getRangeStart
899 * @see #getRangeEnd
900 * @stable ICU 2.0
901 */
902 public int getRangeEnd(int index) {
903 return (list[index*2 + 1] - 1);
904 }
905
906 //----------------------------------------------------------------
907 // Implementation: Pattern parsing
908 //----------------------------------------------------------------
909
910 /**
911 * Parses the given pattern, starting at the given position. The character
912 * at pattern.charAt(pos.getIndex()) must be '[', or the parse fails.
913 * Parsing continues until the corresponding closing ']'. If a syntax error
914 * is encountered between the opening and closing brace, the parse fails.
915 * Upon return from a successful parse, the ParsePosition is updated to
916 * point to the character following the closing ']', and an inversion
917 * list for the parsed pattern is returned. This method
918 * calls itself recursively to parse embedded subpatterns.
919 *
920 * @param pattern the string containing the pattern to be parsed. The
921 * portion of the string from pos.getIndex(), which must be a '[', to the
922 * corresponding closing ']', is parsed.
923 * @param pos upon entry, the position at which to being parsing. The
924 * character at pattern.charAt(pos.getIndex()) must be a '['. Upon return
925 * from a successful parse, pos.getIndex() is either the character after the
926 * closing ']' of the parsed pattern, or pattern.length() if the closing ']'
927 * is the last character of the pattern string.
928 * @return an inversion list for the parsed substring
929 * of <code>pattern</code>
930 * @exception java.lang.IllegalArgumentException if the parse fails.
931 */
932 UnicodeSet applyPattern(String pattern,
933 ParsePosition pos,
934 SymbolTable symbols,
935 int options) {
936
937 // Need to build the pattern in a temporary string because
938 // _applyPattern calls add() etc., which set pat to empty.
939 boolean parsePositionWasNull = pos == null;
940 if (parsePositionWasNull) {
941 pos = new ParsePosition(0);
942 }
943
944 StringBuffer rebuiltPat = new StringBuffer();
945 RuleCharacterIterator chars =
946 new RuleCharacterIterator(pattern, symbols, pos);
947 applyPattern(chars, symbols, rebuiltPat, options);
948 if (chars.inVariable()) {
949 syntaxError(chars, "Extra chars in variable value");
950 }
951 pat = rebuiltPat.toString();
952 if (parsePositionWasNull) {
953 int i = pos.getIndex();
954
955 // Skip over trailing whitespace
956 if ((options & IGNORE_SPACE) != 0) {
957 i = Utility.skipWhitespace(pattern, i);
958 }
959
960 if (i != pattern.length()) {
961 throw new IllegalArgumentException("Parse of \"" + pattern +
962 "\" failed at " + i);
963 }
964 }
965 return this;
966 }
967
968 /**
969 * Parse the pattern from the given RuleCharacterIterator. The
970 * iterator is advanced over the parsed pattern.
971 * @param chars iterator over the pattern characters. Upon return
972 * it will be advanced to the first character after the parsed
973 * pattern, or the end of the iteration if all characters are
974 * parsed.
975 * @param symbols symbol table to use to parse and dereference
976 * variables, or null if none.
977 * @param rebuiltPat the pattern that was parsed, rebuilt or
978 * copied from the input pattern, as appropriate.
979 * @param options a bit mask of zero or more of the following:
980 * IGNORE_SPACE, CASE.
981 */
982 void applyPattern(RuleCharacterIterator chars, SymbolTable symbols,
983 StringBuffer rebuiltPat, int options) {
984
985 // Syntax characters: [ ] ^ - & { }
986
987 // Recognized special forms for chars, sets: c-c s-s s&s
988
989 int opts = RuleCharacterIterator.PARSE_VARIABLES |
990 RuleCharacterIterator.PARSE_ESCAPES;
991 if ((options & IGNORE_SPACE) != 0) {
992 opts |= RuleCharacterIterator.SKIP_WHITESPACE;
993 }
994
995 StringBuffer pat = new StringBuffer(), buf = null;
996 boolean usePat = false;
997 UnicodeSet scratch = null;
998 Object backup = null;
999
1000 // mode: 0=before [, 1=between [...], 2=after ]
1001 // lastItem: 0=none, 1=char, 2=set
1002 int lastItem = 0, lastChar = 0, mode = 0;
1003 char op = 0;
1004
1005 boolean invert = false;
1006
1007 clear();
1008
1009 while (mode != 2 && !chars.atEnd()) {
1010 if (false) {
1011 // Debugging assertion
1012 if (!((lastItem == 0 && op == 0) ||
1013 (lastItem == 1 && (op == 0 || op == '-')) ||
1014 (lastItem == 2 && (op == 0 || op == '-' || op == '&')))) {
1015 throw new IllegalArgumentException();
1016 }
1017 }
1018
1019 int c = 0;
1020 boolean literal = false;
1021 UnicodeSet nested = null;
1022
1023 // -------- Check for property pattern
1024
1025 // setMode: 0=none, 1=unicodeset, 2=propertypat, 3=preparsed
1026 int setMode = 0;
1027 if (resemblesPropertyPattern(chars, opts)) {
1028 setMode = 2;
1029 }
1030
1031 // -------- Parse '[' of opening delimiter OR nested set.
1032 // If there is a nested set, use `setMode' to define how
1033 // the set should be parsed. If the '[' is part of the
1034 // opening delimiter for this pattern, parse special
1035 // strings "[", "[^", "[-", and "[^-". Check for stand-in
1036 // characters representing a nested set in the symbol
1037 // table.
1038
1039 else {
1040 // Prepare to backup if necessary
1041 backup = chars.getPos(backup);
1042 c = chars.next(opts);
1043 literal = chars.isEscaped();
1044
1045 if (c == '[' && !literal) {
1046 if (mode == 1) {
1047 chars.setPos(backup); // backup
1048 setMode = 1;
1049 } else {
1050 // Handle opening '[' delimiter
1051 mode = 1;
1052 pat.append('[');
1053 backup = chars.getPos(backup); // prepare to backup
1054 c = chars.next(opts);
1055 literal = chars.isEscaped();
1056 if (c == '^' && !literal) {
1057 invert = true;
1058 pat.append('^');
1059 backup = chars.getPos(backup); // prepare to backup
1060 c = chars.next(opts);
1061 literal = chars.isEscaped();
1062 }
1063 // Fall through to handle special leading '-';
1064 // otherwise restart loop for nested [], \p{}, etc.
1065 if (c == '-') {
1066 literal = true;
1067 // Fall through to handle literal '-' below
1068 } else {
1069 chars.setPos(backup); // backup
1070 continue;
1071 }
1072 }
1073 } else if (symbols != null) {
1074 UnicodeMatcher m = symbols.lookupMatcher(c); // may be null
1075 if (m != null) {
1076 try {
1077 nested = (UnicodeSet) m;
1078 setMode = 3;
1079 } catch (ClassCastException e) {
1080 syntaxError(chars, "Syntax error");
1081 }
1082 }
1083 }
1084 }
1085
1086 // -------- Handle a nested set. This either is inline in
1087 // the pattern or represented by a stand-in that has
1088 // previously been parsed and was looked up in the symbol
1089 // table.
1090
1091 if (setMode != 0) {
1092 if (lastItem == 1) {
1093 if (op != 0) {
1094 syntaxError(chars, "Char expected after operator");
1095 }
1096 add(lastChar, lastChar);
1097 _appendToPat(pat, lastChar, false);
1098 lastItem = op = 0;
1099 }
1100
1101 if (op == '-' || op == '&') {
1102 pat.append(op);
1103 }
1104
1105 if (nested == null) {
1106 if (scratch == null) scratch = new UnicodeSet();
1107 nested = scratch;
1108 }
1109 switch (setMode) {
1110 case 1:
1111 nested.applyPattern(chars, symbols, pat, options);
1112 break;
1113 case 2:
1114 chars.skipIgnored(opts);
1115 nested.applyPropertyPattern(chars, pat, symbols);
1116 break;
1117 case 3: // `nested' already parsed
1118 nested._toPattern(pat, false);
1119 break;
1120 }
1121
1122 usePat = true;
1123
1124 if (mode == 0) {
1125 // Entire pattern is a category; leave parse loop
1126 set(nested);
1127 mode = 2;
1128 break;
1129 }
1130
1131 switch (op) {
1132 case '-':
1133 removeAll(nested);
1134 break;
1135 case '&':
1136 retainAll(nested);
1137 break;
1138 case 0:
1139 addAll(nested);
1140 break;
1141 }
1142
1143 op = 0;
1144 lastItem = 2;
1145
1146 continue;
1147 }
1148
1149 if (mode == 0) {
1150 syntaxError(chars, "Missing '['");
1151 }
1152
1153 // -------- Parse special (syntax) characters. If the
1154 // current character is not special, or if it is escaped,
1155 // then fall through and handle it below.
1156
1157 if (!literal) {
1158 switch (c) {
1159 case ']':
1160 if (lastItem == 1) {
1161 add(lastChar, lastChar);
1162 _appendToPat(pat, lastChar, false);
1163 }
1164 // Treat final trailing '-' as a literal
1165 if (op == '-') {
1166 add(op, op);
1167 pat.append(op);
1168 } else if (op == '&') {
1169 syntaxError(chars, "Trailing '&'");
1170 }
1171 pat.append(']');
1172 mode = 2;
1173 continue;
1174 case '-':
1175 if (op == 0) {
1176 if (lastItem != 0) {
1177 op = (char) c;
1178 continue;
1179 } else {
1180 // Treat final trailing '-' as a literal
1181 add(c, c);
1182 c = chars.next(opts);
1183 literal = chars.isEscaped();
1184 if (c == ']' && !literal) {
1185 pat.append("-]");
1186 mode = 2;
1187 continue;
1188 }
1189 }
1190 }
1191 syntaxError(chars, "'-' not after char or set");
1192 case '&':
1193 if (lastItem == 2 && op == 0) {
1194 op = (char) c;
1195 continue;
1196 }
1197 syntaxError(chars, "'&' not after set");
1198 case '^':
1199 syntaxError(chars, "'^' not after '['");
1200 case '{':
1201 if (op != 0) {
1202 syntaxError(chars, "Missing operand after operator");
1203 }
1204 if (lastItem == 1) {
1205 add(lastChar, lastChar);
1206 _appendToPat(pat, lastChar, false);
1207 }
1208 lastItem = 0;
1209 if (buf == null) {
1210 buf = new StringBuffer();
1211 } else {
1212 buf.setLength(0);
1213 }
1214 boolean ok = false;
1215 while (!chars.atEnd()) {
1216 c = chars.next(opts);
1217 literal = chars.isEscaped();
1218 if (c == '}' && !literal) {
1219 ok = true;
1220 break;
1221 }
1222 UTF16.append(buf, c);
1223 }
1224 if (buf.length() < 1 || !ok) {
1225 syntaxError(chars, "Invalid multicharacter string");
1226 }
1227 // We have new string. Add it to set and continue;
1228 // we don't need to drop through to the further
1229 // processing
1230 add(buf.toString());
1231 pat.append('{');
1232 _appendToPat(pat, buf.toString(), false);
1233 pat.append('}');
1234 continue;
1235 case SymbolTable.SYMBOL_REF:
1236 // symbols nosymbols
1237 // [a-$] error error (ambiguous)
1238 // [a$] anchor anchor
1239 // [a-$x] var "x"* literal '$'
1240 // [a-$.] error literal '$'
1241 // *We won't get here in the case of var "x"
1242 backup = chars.getPos(backup);
1243 c = chars.next(opts);
1244 literal = chars.isEscaped();
1245 boolean anchor = (c == ']' && !literal);
1246 if (symbols == null && !anchor) {
1247 c = SymbolTable.SYMBOL_REF;
1248 chars.setPos(backup);
1249 break; // literal '$'
1250 }
1251 if (anchor && op == 0) {
1252 if (lastItem == 1) {
1253 add(lastChar, lastChar);
1254 _appendToPat(pat, lastChar, false);
1255 }
1256 add(UnicodeMatcher.ETHER);
1257 usePat = true;
1258 pat.append(SymbolTable.SYMBOL_REF).append(']');
1259 mode = 2;
1260 continue;
1261 }
1262 syntaxError(chars, "Unquoted '$'");
1263 default:
1264 break;
1265 }
1266 }
1267
1268 // -------- Parse literal characters. This includes both
1269 // escaped chars ("\u4E01") and non-syntax characters
1270 // ("a").
1271
1272 switch (lastItem) {
1273 case 0:
1274 lastItem = 1;
1275 lastChar = c;
1276 break;
1277 case 1:
1278 if (op == '-') {
1279 if (lastChar >= c) {
1280 // Don't allow redundant (a-a) or empty (b-a) ranges;
1281 // these are most likely typos.
1282 syntaxError(chars, "Invalid range");
1283 }
1284 add(lastChar, c);
1285 _appendToPat(pat, lastChar, false);
1286 pat.append(op);
1287 _appendToPat(pat, c, false);
1288 lastItem = op = 0;
1289 } else {
1290 add(lastChar, lastChar);
1291 _appendToPat(pat, lastChar, false);
1292 lastChar = c;
1293 }
1294 break;
1295 case 2:
1296 if (op != 0) {
1297 syntaxError(chars, "Set expected after operator");
1298 }
1299 lastChar = c;
1300 lastItem = 1;
1301 break;
1302 }
1303 }
1304
1305 if (mode != 2) {
1306 syntaxError(chars, "Missing ']'");
1307 }
1308
1309 chars.skipIgnored(opts);
1310
1311 if (invert) {
1312 complement();
1313 }
1314
1315 // Use the rebuilt pattern (pat) only if necessary. Prefer the
1316 // generated pattern.
1317 if (usePat) {
1318 rebuiltPat.append(pat.toString());
1319 } else {
1320 _generatePattern(rebuiltPat, false);
1321 }
1322 }
1323
1324 private static void syntaxError(RuleCharacterIterator chars, String msg) {
1325 throw new IllegalArgumentException("Error: " + msg + " at \"" +
1326 Utility.escape(chars.toString()) +
1327 '"');
1328 }
1329
1330 //----------------------------------------------------------------
1331 // Implementation: Utility methods
1332 //----------------------------------------------------------------
1333
1334 private void ensureCapacity(int newLen) {
1335 if (newLen <= list.length) return;
1336 int[] temp = new int[newLen + GROW_EXTRA];
1337 System.arraycopy(list, 0, temp, 0, len);
1338 list = temp;
1339 }
1340
1341 private void ensureBufferCapacity(int newLen) {
1342 if (buffer != null && newLen <= buffer.length) return;
1343 buffer = new int[newLen + GROW_EXTRA];
1344 }
1345
1346 /**
1347 * Assumes start <= end.
1348 */
1349 private int[] range(int start, int end) {
1350 if (rangeList == null) {
1351 rangeList = new int[] { start, end+1, HIGH };
1352 } else {
1353 rangeList[0] = start;
1354 rangeList[1] = end+1;
1355 }
1356 return rangeList;
1357 }
1358
1359 //----------------------------------------------------------------
1360 // Implementation: Fundamental operations
1361 //----------------------------------------------------------------
1362
1363 // polarity = 0, 3 is normal: x xor y
1364 // polarity = 1, 2: x xor ~y == x === y
1365
1366 private UnicodeSet xor(int[] other, int otherLen, int polarity) {
1367 ensureBufferCapacity(len + otherLen);
1368 int i = 0, j = 0, k = 0;
1369 int a = list[i++];
1370 int b;
1371 if (polarity == 1 || polarity == 2) {
1372 b = LOW;
1373 if (other[j] == LOW) { // skip base if already LOW
1374 ++j;
1375 b = other[j];
1376 }
1377 } else {
1378 b = other[j++];
1379 }
1380 // simplest of all the routines
1381 // sort the values, discarding identicals!
1382 while (true) {
1383 if (a < b) {
1384 buffer[k++] = a;
1385 a = list[i++];
1386 } else if (b < a) {
1387 buffer[k++] = b;
1388 b = other[j++];
1389 } else if (a != HIGH) { // at this point, a == b
1390 // discard both values!
1391 a = list[i++];
1392 b = other[j++];
1393 } else { // DONE!
1394 buffer[k++] = HIGH;
1395 len = k;
1396 break;
1397 }
1398 }
1399 // swap list and buffer
1400 int[] temp = list;
1401 list = buffer;
1402 buffer = temp;
1403 pat = null;
1404 return this;
1405 }
1406
1407 // polarity = 0 is normal: x union y
1408 // polarity = 2: x union ~y
1409 // polarity = 1: ~x union y
1410 // polarity = 3: ~x union ~y
1411
1412 private UnicodeSet add(int[] other, int otherLen, int polarity) {
1413 ensureBufferCapacity(len + otherLen);
1414 int i = 0, j = 0, k = 0;
1415 int a = list[i++];
1416 int b = other[j++];
1417 // change from xor is that we have to check overlapping pairs
1418 // polarity bit 1 means a is second, bit 2 means b is.
1419 main:
1420 while (true) {
1421 switch (polarity) {
1422 case 0: // both first; take lower if unequal
1423 if (a < b) { // take a
1424 // Back up over overlapping ranges in buffer[]
1425 if (k > 0 && a <= buffer[k-1]) {
1426 // Pick latter end value in buffer[] vs. list[]
1427 a = max(list[i], buffer[--k]);
1428 } else {
1429 // No overlap
1430 buffer[k++] = a;
1431 a = list[i];
1432 }
1433 i++; // Common if/else code factored out
1434 polarity ^= 1;
1435 } else if (b < a) { // take b
1436 if (k > 0 && b <= buffer[k-1]) {
1437 b = max(other[j], buffer[--k]);
1438 } else {
1439 buffer[k++] = b;
1440 b = other[j];
1441 }
1442 j++;
1443 polarity ^= 2;
1444 } else { // a == b, take a, drop b
1445 if (a == HIGH) break main;
1446 // This is symmetrical; it doesn't matter if
1447 // we backtrack with a or b. - liu
1448 if (k > 0 && a <= buffer[k-1]) {
1449 a = max(list[i], buffer[--k]);
1450 } else {
1451 // No overlap
1452 buffer[k++] = a;
1453 a = list[i];
1454 }
1455 i++;
1456 polarity ^= 1;
1457 b = other[j++]; polarity ^= 2;
1458 }
1459 break;
1460 case 3: // both second; take higher if unequal, and drop other
1461 if (b <= a) { // take a
1462 if (a == HIGH) break main;
1463 buffer[k++] = a;
1464 } else { // take b
1465 if (b == HIGH) break main;
1466 buffer[k++] = b;
1467 }
1468 a = list[i++]; polarity ^= 1; // factored common code
1469 b = other[j++]; polarity ^= 2;
1470 break;
1471 case 1: // a second, b first; if b < a, overlap
1472 if (a < b) { // no overlap, take a
1473 buffer[k++] = a; a = list[i++]; polarity ^= 1;
1474 } else if (b < a) { // OVERLAP, drop b
1475 b = other[j++]; polarity ^= 2;
1476 } else { // a == b, drop both!
1477 if (a == HIGH) break main;
1478 a = list[i++]; polarity ^= 1;
1479 b = other[j++]; polarity ^= 2;
1480 }
1481 break;
1482 case 2: // a first, b second; if a < b, overlap
1483 if (b < a) { // no overlap, take b
1484 buffer[k++] = b; b = other[j++]; polarity ^= 2;
1485 } else if (a < b) { // OVERLAP, drop a
1486 a = list[i++]; polarity ^= 1;
1487 } else { // a == b, drop both!
1488 if (a == HIGH) break main;
1489 a = list[i++]; polarity ^= 1;
1490 b = other[j++]; polarity ^= 2;
1491 }
1492 break;
1493 }
1494 }
1495 buffer[k++] = HIGH; // terminate
1496 len = k;
1497 // swap list and buffer
1498 int[] temp = list;
1499 list = buffer;
1500 buffer = temp;
1501 pat = null;
1502 return this;
1503 }
1504
1505 // polarity = 0 is normal: x intersect y
1506 // polarity = 2: x intersect ~y == set-minus
1507 // polarity = 1: ~x intersect y
1508 // polarity = 3: ~x intersect ~y
1509
1510 private UnicodeSet retain(int[] other, int otherLen, int polarity) {
1511 ensureBufferCapacity(len + otherLen);
1512 int i = 0, j = 0, k = 0;
1513 int a = list[i++];
1514 int b = other[j++];
1515 // change from xor is that we have to check overlapping pairs
1516 // polarity bit 1 means a is second, bit 2 means b is.
1517 main:
1518 while (true) {
1519 switch (polarity) {
1520 case 0: // both first; drop the smaller
1521 if (a < b) { // drop a
1522 a = list[i++]; polarity ^= 1;
1523 } else if (b < a) { // drop b
1524 b = other[j++]; polarity ^= 2;
1525 } else { // a == b, take one, drop other
1526 if (a == HIGH) break main;
1527 buffer[k++] = a; a = list[i++]; polarity ^= 1;
1528 b = other[j++]; polarity ^= 2;
1529 }
1530 break;
1531 case 3: // both second; take lower if unequal
1532 if (a < b) { // take a
1533 buffer[k++] = a; a = list[i++]; polarity ^= 1;
1534 } else if (b < a) { // take b
1535 buffer[k++] = b; b = other[j++]; polarity ^= 2;
1536 } else { // a == b, take one, drop other
1537 if (a == HIGH) break main;
1538 buffer[k++] = a; a = list[i++]; polarity ^= 1;
1539 b = other[j++]; polarity ^= 2;
1540 }
1541 break;
1542 case 1: // a second, b first;
1543 if (a < b) { // NO OVERLAP, drop a
1544 a = list[i++]; polarity ^= 1;
1545 } else if (b < a) { // OVERLAP, take b
1546 buffer[k++] = b; b = other[j++]; polarity ^= 2;
1547 } else { // a == b, drop both!
1548 if (a == HIGH) break main;
1549 a = list[i++]; polarity ^= 1;
1550 b = other[j++]; polarity ^= 2;
1551 }
1552 break;
1553 case 2: // a first, b second; if a < b, overlap
1554 if (b < a) { // no overlap, drop b
1555 b = other[j++]; polarity ^= 2;
1556 } else if (a < b) { // OVERLAP, take a
1557 buffer[k++] = a; a = list[i++]; polarity ^= 1;
1558 } else { // a == b, drop both!
1559 if (a == HIGH) break main;
1560 a = list[i++]; polarity ^= 1;
1561 b = other[j++]; polarity ^= 2;
1562 }
1563 break;
1564 }
1565 }
1566 buffer[k++] = HIGH; // terminate
1567 len = k;
1568 // swap list and buffer
1569 int[] temp = list;
1570 list = buffer;
1571 buffer = temp;
1572 pat = null;
1573 return this;
1574 }
1575
1576 private static final int max(int a, int b) {
1577 return (a > b) ? a : b;
1578 }
1579
1580 //----------------------------------------------------------------
1581 // Generic filter-based scanning code
1582 //----------------------------------------------------------------
1583
1584 private static interface Filter {
1585 boolean contains(int codePoint);
1586 }
1587
1588 // VersionInfo for unassigned characters
1589 static final VersionInfo NO_VERSION = VersionInfo.getInstance(0, 0, 0, 0);
1590
1591 private static class VersionFilter implements Filter {
1592 VersionInfo version;
1593 VersionFilter(VersionInfo version) { this.version = version; }
1594 public boolean contains(int ch) {
1595 VersionInfo v = UCharacter.getAge(ch);
1596 // Reference comparison ok; VersionInfo caches and reuses
1597 // unique objects.
1598 return v != NO_VERSION &&
1599 v.compareTo(version) <= 0;
1600 }
1601 }
1602
1603 private static synchronized UnicodeSet getInclusions() {
1604 if (INCLUSIONS == null) {
1605 UCharacterProperty property = UCharacterProperty.getInstance();
1606 INCLUSIONS = property.getInclusions();
1607 }
1608 return INCLUSIONS;
1609 }
1610
1611 /**
1612 * Generic filter-based scanning code for UCD property UnicodeSets.
1613 */
1614 private UnicodeSet applyFilter(Filter filter) {
1615 // Walk through all Unicode characters, noting the start
1616 // and end of each range for which filter.contain(c) is
1617 // true. Add each range to a set.
1618 //
1619 // To improve performance, use the INCLUSIONS set, which
1620 // encodes information about character ranges that are known
1621 // to have identical properties, such as the CJK Ideographs
1622 // from U+4E00 to U+9FA5. INCLUSIONS contains all characters
1623 // except the first characters of such ranges.
1624 //
1625 // TODO Where possible, instead of scanning over code points,
1626 // use internal property data to initialize UnicodeSets for
1627 // those properties. Scanning code points is slow.
1628
1629 clear();
1630
1631 int startHasProperty = -1;
1632 UnicodeSet inclusions = getInclusions();
1633 int limitRange = inclusions.getRangeCount();
1634
1635 for (int j=0; j<limitRange; ++j) {
1636 // get current range
1637 int start = inclusions.getRangeStart(j);
1638 int end = inclusions.getRangeEnd(j);
1639
1640 // for all the code points in the range, process
1641 for (int ch = start; ch <= end; ++ch) {
1642 // only add to the unicodeset on inflection points --
1643 // where the hasProperty value changes to false
1644 if (filter.contains(ch)) {
1645 if (startHasProperty < 0) {
1646 startHasProperty = ch;
1647 }
1648 } else if (startHasProperty >= 0) {
1649 add(startHasProperty, ch-1);
1650 startHasProperty = -1;
1651 }
1652 }
1653 }
1654 if (startHasProperty >= 0) {
1655 add(startHasProperty, 0x10FFFF);
1656 }
1657
1658 return this;
1659 }
1660
1661
1662 /**
1663 * Remove leading and trailing rule white space and compress
1664 * internal rule white space to a single space character.
1665 *
1666 * @see UCharacterProperty#isRuleWhiteSpace
1667 */
1668 private static String mungeCharName(String source) {
1669 StringBuffer buf = new StringBuffer();
1670 for (int i=0; i<source.length(); ) {
1671 int ch = UTF16.charAt(source, i);
1672 i += UTF16.getCharCount(ch);
1673 if (UCharacterProperty.isRuleWhiteSpace(ch)) {
1674 if (buf.length() == 0 ||
1675 buf.charAt(buf.length() - 1) == ' ') {
1676 continue;
1677 }
1678 ch = ' '; // convert to ' '
1679 }
1680 UTF16.append(buf, ch);
1681 }
1682 if (buf.length() != 0 &&
1683 buf.charAt(buf.length() - 1) == ' ') {
1684 buf.setLength(buf.length() - 1);
1685 }
1686 return buf.toString();
1687 }
1688
1689 //----------------------------------------------------------------
1690 // Property set API
1691 //----------------------------------------------------------------
1692
1693 /**
1694 * Modifies this set to contain those code points which have the
1695 * given value for the given property. Prior contents of this
1696 * set are lost.
1697 * @param propertyAlias
1698 * @param valueAlias
1699 * @param symbols if not null, then symbols are first called to see if a property
1700 * is available. If true, then everything else is skipped.
1701 * @return this set
1702 * @draft ICU 3.2
1703 * @deprecated This is a draft API and might change in a future release of ICU.
1704 */
1705 public UnicodeSet applyPropertyAlias(String propertyAlias,
1706 String valueAlias, SymbolTable symbols) {
1707 if (propertyAlias.equals("Age"))
1708 {
1709 // Must munge name, since
1710 // VersionInfo.getInstance() does not do
1711 // 'loose' matching.
1712 VersionInfo version = VersionInfo.getInstance(mungeCharName(valueAlias));
1713 applyFilter(new VersionFilter(version));
1714 return this;
1715 }
1716 else
1717 throw new IllegalArgumentException("Unsupported property");
1718 }
1719
1720 /**
1721 * Return true if the given iterator appears to point at a
1722 * property pattern. Regardless of the result, return with the
1723 * iterator unchanged.
1724 * @param chars iterator over the pattern characters. Upon return
1725 * it will be unchanged.
1726 * @param iterOpts RuleCharacterIterator options
1727 */
1728 private static boolean resemblesPropertyPattern(RuleCharacterIterator chars,
1729 int iterOpts) {
1730 boolean result = false;
1731 iterOpts &= ~RuleCharacterIterator.PARSE_ESCAPES;
1732 Object pos = chars.getPos(null);
1733 int c = chars.next(iterOpts);
1734 if (c == '[' || c == '\\') {
1735 int d = chars.next(iterOpts & ~RuleCharacterIterator.SKIP_WHITESPACE);
1736 result = (c == '[') ? (d == ':') :
1737 (d == 'N' || d == 'p' || d == 'P');
1738 }
1739 chars.setPos(pos);
1740 return result;
1741 }
1742
1743 /**
1744 * Parse the given property pattern at the given parse position.
1745 * @param symbols TODO
1746 */
1747 private UnicodeSet applyPropertyPattern(String pattern, ParsePosition ppos, SymbolTable symbols) {
1748 int pos = ppos.getIndex();
1749
1750 // On entry, ppos should point to one of the following locations:
1751
1752 // Minimum length is 5 characters, e.g. \p{L}
1753 if ((pos+5) > pattern.length()) {
1754 return null;
1755 }
1756
1757 boolean posix = false; // true for [:pat:], false for \p{pat} \P{pat} \N{pat}
1758 boolean isName = false; // true for \N{pat}, o/w false
1759 boolean invert = false;
1760
1761 // Look for an opening [:, [:^, \p, or \P
1762 if (pattern.regionMatches(pos, "[:", 0, 2)) {
1763 posix = true;
1764 pos = Utility.skipWhitespace(pattern, pos+2);
1765 if (pos < pattern.length() && pattern.charAt(pos) == '^') {
1766 ++pos;
1767 invert = true;
1768 }
1769 } else if (pattern.regionMatches(true, pos, "\\p", 0, 2) ||
1770 pattern.regionMatches(pos, "\\N", 0, 2)) {
1771 char c = pattern.charAt(pos+1);
1772 invert = (c == 'P');
1773 isName = (c == 'N');
1774 pos = Utility.skipWhitespace(pattern, pos+2);
1775 if (pos == pattern.length() || pattern.charAt(pos++) != '{') {
1776 // Syntax error; "\p" or "\P" not followed by "{"
1777 return null;
1778 }
1779 } else {
1780 // Open delimiter not seen
1781 return null;
1782 }
1783
1784 // Look for the matching close delimiter, either :] or }
1785 int close = pattern.indexOf(posix ? ":]" : "}", pos);
1786 if (close < 0) {
1787 // Syntax error; close delimiter missing
1788 return null;
1789 }
1790
1791 // Look for an '=' sign. If this is present, we will parse a
1792 // medium \p{gc=Cf} or long \p{GeneralCategory=Format}
1793 // pattern.
1794 int equals = pattern.indexOf('=', pos);
1795 String propName, valueName;
1796 if (equals >= 0 && equals < close && !isName) {
1797 // Equals seen; parse medium/long pattern
1798 propName = pattern.substring(pos, equals);
1799 valueName = pattern.substring(equals+1, close);
1800 }
1801
1802 else {
1803 // Handle case where no '=' is seen, and \N{}
1804 propName = pattern.substring(pos, close);
1805 valueName = "";
1806
1807 // Handle \N{name}
1808 if (isName) {
1809 // This is a little inefficient since it means we have to
1810 // parse "na" back to UProperty.NAME even though we already
1811 // know it's UProperty.NAME. If we refactor the API to
1812 // support args of (int, String) then we can remove
1813 // "na" and make this a little more efficient.
1814 valueName = propName;
1815 propName = "na";
1816 }
1817 }
1818
1819 applyPropertyAlias(propName, valueName, symbols);
1820
1821 if (invert) {
1822 complement();
1823 }
1824
1825 // Move to the limit position after the close delimiter
1826 ppos.setIndex(close + (posix ? 2 : 1));
1827
1828 return this;
1829 }
1830
1831 /**
1832 * Parse a property pattern.
1833 * @param chars iterator over the pattern characters. Upon return
1834 * it will be advanced to the first character after the parsed
1835 * pattern, or the end of the iteration if all characters are
1836 * parsed.
1837 * @param rebuiltPat the pattern that was parsed, rebuilt or
1838 * copied from the input pattern, as appropriate.
1839 * @param symbols TODO
1840 */
1841 private void applyPropertyPattern(RuleCharacterIterator chars,
1842 StringBuffer rebuiltPat, SymbolTable symbols) {
1843 String pat = chars.lookahead();
1844 ParsePosition pos = new ParsePosition(0);
1845 applyPropertyPattern(pat, pos, symbols);
1846 if (pos.getIndex() == 0) {
1847 syntaxError(chars, "Invalid property pattern");
1848 }
1849 chars.jumpahead(pos.getIndex());
1850 rebuiltPat.append(pat.substring(0, pos.getIndex()));
1851 }
1852
1853 //----------------------------------------------------------------
1854 // Case folding API
1855 //----------------------------------------------------------------
1856
1857 /**
1858 * Bitmask for constructor and applyPattern() indicating that
1859 * white space should be ignored. If set, ignore characters for
1860 * which UCharacterProperty.isRuleWhiteSpace() returns true,
1861 * unless they are quoted or escaped. This may be ORed together
1862 * with other selectors.
1863 * @internal
1864 */
1865 public static final int IGNORE_SPACE = 1;
1866
1867}