J. Duke | 319a3b9 | 2007-12-01 00:00:00 +0000 | [diff] [blame^] | 1 | /* |
| 2 | * Copyright 1997-2006 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 | * (C) Copyright Taligent, Inc. 1996-1998 - All Rights Reserved |
| 28 | * (C) Copyright IBM Corp. 1996-1998 - All Rights Reserved |
| 29 | * |
| 30 | * The original version of this source code and documentation is copyrighted |
| 31 | * and owned by Taligent, Inc., a wholly-owned subsidiary of IBM. These |
| 32 | * materials are provided under terms of a License Agreement between Taligent |
| 33 | * and Sun. This technology is protected by multiple US and International |
| 34 | * patents. This notice and attribution to Taligent may not be removed. |
| 35 | * Taligent is a registered trademark of Taligent, Inc. |
| 36 | * |
| 37 | */ |
| 38 | |
| 39 | package java.text; |
| 40 | |
| 41 | import java.text.spi.CollatorProvider; |
| 42 | import java.util.Locale; |
| 43 | import java.util.MissingResourceException; |
| 44 | import java.util.ResourceBundle; |
| 45 | import java.util.spi.LocaleServiceProvider; |
| 46 | import sun.misc.SoftCache; |
| 47 | import sun.util.resources.LocaleData; |
| 48 | import sun.util.LocaleServiceProviderPool; |
| 49 | |
| 50 | |
| 51 | /** |
| 52 | * The <code>Collator</code> class performs locale-sensitive |
| 53 | * <code>String</code> comparison. You use this class to build |
| 54 | * searching and sorting routines for natural language text. |
| 55 | * |
| 56 | * <p> |
| 57 | * <code>Collator</code> is an abstract base class. Subclasses |
| 58 | * implement specific collation strategies. One subclass, |
| 59 | * <code>RuleBasedCollator</code>, is currently provided with |
| 60 | * the Java Platform and is applicable to a wide set of languages. Other |
| 61 | * subclasses may be created to handle more specialized needs. |
| 62 | * |
| 63 | * <p> |
| 64 | * Like other locale-sensitive classes, you can use the static |
| 65 | * factory method, <code>getInstance</code>, to obtain the appropriate |
| 66 | * <code>Collator</code> object for a given locale. You will only need |
| 67 | * to look at the subclasses of <code>Collator</code> if you need |
| 68 | * to understand the details of a particular collation strategy or |
| 69 | * if you need to modify that strategy. |
| 70 | * |
| 71 | * <p> |
| 72 | * The following example shows how to compare two strings using |
| 73 | * the <code>Collator</code> for the default locale. |
| 74 | * <blockquote> |
| 75 | * <pre> |
| 76 | * // Compare two strings in the default locale |
| 77 | * Collator myCollator = Collator.getInstance(); |
| 78 | * if( myCollator.compare("abc", "ABC") < 0 ) |
| 79 | * System.out.println("abc is less than ABC"); |
| 80 | * else |
| 81 | * System.out.println("abc is greater than or equal to ABC"); |
| 82 | * </pre> |
| 83 | * </blockquote> |
| 84 | * |
| 85 | * <p> |
| 86 | * You can set a <code>Collator</code>'s <em>strength</em> property |
| 87 | * to determine the level of difference considered significant in |
| 88 | * comparisons. Four strengths are provided: <code>PRIMARY</code>, |
| 89 | * <code>SECONDARY</code>, <code>TERTIARY</code>, and <code>IDENTICAL</code>. |
| 90 | * The exact assignment of strengths to language features is |
| 91 | * locale dependant. For example, in Czech, "e" and "f" are considered |
| 92 | * primary differences, while "e" and "ě" are secondary differences, |
| 93 | * "e" and "E" are tertiary differences and "e" and "e" are identical. |
| 94 | * The following shows how both case and accents could be ignored for |
| 95 | * US English. |
| 96 | * <blockquote> |
| 97 | * <pre> |
| 98 | * //Get the Collator for US English and set its strength to PRIMARY |
| 99 | * Collator usCollator = Collator.getInstance(Locale.US); |
| 100 | * usCollator.setStrength(Collator.PRIMARY); |
| 101 | * if( usCollator.compare("abc", "ABC") == 0 ) { |
| 102 | * System.out.println("Strings are equivalent"); |
| 103 | * } |
| 104 | * </pre> |
| 105 | * </blockquote> |
| 106 | * <p> |
| 107 | * For comparing <code>String</code>s exactly once, the <code>compare</code> |
| 108 | * method provides the best performance. When sorting a list of |
| 109 | * <code>String</code>s however, it is generally necessary to compare each |
| 110 | * <code>String</code> multiple times. In this case, <code>CollationKey</code>s |
| 111 | * provide better performance. The <code>CollationKey</code> class converts |
| 112 | * a <code>String</code> to a series of bits that can be compared bitwise |
| 113 | * against other <code>CollationKey</code>s. A <code>CollationKey</code> is |
| 114 | * created by a <code>Collator</code> object for a given <code>String</code>. |
| 115 | * <br> |
| 116 | * <strong>Note:</strong> <code>CollationKey</code>s from different |
| 117 | * <code>Collator</code>s can not be compared. See the class description |
| 118 | * for {@link CollationKey} |
| 119 | * for an example using <code>CollationKey</code>s. |
| 120 | * |
| 121 | * @see RuleBasedCollator |
| 122 | * @see CollationKey |
| 123 | * @see CollationElementIterator |
| 124 | * @see Locale |
| 125 | * @author Helena Shih, Laura Werner, Richard Gillam |
| 126 | */ |
| 127 | |
| 128 | public abstract class Collator |
| 129 | implements java.util.Comparator<Object>, Cloneable |
| 130 | { |
| 131 | /** |
| 132 | * Collator strength value. When set, only PRIMARY differences are |
| 133 | * considered significant during comparison. The assignment of strengths |
| 134 | * to language features is locale dependant. A common example is for |
| 135 | * different base letters ("a" vs "b") to be considered a PRIMARY difference. |
| 136 | * @see java.text.Collator#setStrength |
| 137 | * @see java.text.Collator#getStrength |
| 138 | */ |
| 139 | public final static int PRIMARY = 0; |
| 140 | /** |
| 141 | * Collator strength value. When set, only SECONDARY and above differences are |
| 142 | * considered significant during comparison. The assignment of strengths |
| 143 | * to language features is locale dependant. A common example is for |
| 144 | * different accented forms of the same base letter ("a" vs "\u00E4") to be |
| 145 | * considered a SECONDARY difference. |
| 146 | * @see java.text.Collator#setStrength |
| 147 | * @see java.text.Collator#getStrength |
| 148 | */ |
| 149 | public final static int SECONDARY = 1; |
| 150 | /** |
| 151 | * Collator strength value. When set, only TERTIARY and above differences are |
| 152 | * considered significant during comparison. The assignment of strengths |
| 153 | * to language features is locale dependant. A common example is for |
| 154 | * case differences ("a" vs "A") to be considered a TERTIARY difference. |
| 155 | * @see java.text.Collator#setStrength |
| 156 | * @see java.text.Collator#getStrength |
| 157 | */ |
| 158 | public final static int TERTIARY = 2; |
| 159 | |
| 160 | /** |
| 161 | * Collator strength value. When set, all differences are |
| 162 | * considered significant during comparison. The assignment of strengths |
| 163 | * to language features is locale dependant. A common example is for control |
| 164 | * characters ("\u0001" vs "\u0002") to be considered equal at the |
| 165 | * PRIMARY, SECONDARY, and TERTIARY levels but different at the IDENTICAL |
| 166 | * level. Additionally, differences between pre-composed accents such as |
| 167 | * "\u00C0" (A-grave) and combining accents such as "A\u0300" |
| 168 | * (A, combining-grave) will be considered significant at the IDENTICAL |
| 169 | * level if decomposition is set to NO_DECOMPOSITION. |
| 170 | */ |
| 171 | public final static int IDENTICAL = 3; |
| 172 | |
| 173 | /** |
| 174 | * Decomposition mode value. With NO_DECOMPOSITION |
| 175 | * set, accented characters will not be decomposed for collation. This |
| 176 | * is the default setting and provides the fastest collation but |
| 177 | * will only produce correct results for languages that do not use accents. |
| 178 | * @see java.text.Collator#getDecomposition |
| 179 | * @see java.text.Collator#setDecomposition |
| 180 | */ |
| 181 | public final static int NO_DECOMPOSITION = 0; |
| 182 | |
| 183 | /** |
| 184 | * Decomposition mode value. With CANONICAL_DECOMPOSITION |
| 185 | * set, characters that are canonical variants according to Unicode |
| 186 | * standard will be decomposed for collation. This should be used to get |
| 187 | * correct collation of accented characters. |
| 188 | * <p> |
| 189 | * CANONICAL_DECOMPOSITION corresponds to Normalization Form D as |
| 190 | * described in |
| 191 | * <a href="http://www.unicode.org/unicode/reports/tr15/tr15-23.html">Unicode |
| 192 | * Technical Report #15</a>. |
| 193 | * @see java.text.Collator#getDecomposition |
| 194 | * @see java.text.Collator#setDecomposition |
| 195 | */ |
| 196 | public final static int CANONICAL_DECOMPOSITION = 1; |
| 197 | |
| 198 | /** |
| 199 | * Decomposition mode value. With FULL_DECOMPOSITION |
| 200 | * set, both Unicode canonical variants and Unicode compatibility variants |
| 201 | * will be decomposed for collation. This causes not only accented |
| 202 | * characters to be collated, but also characters that have special formats |
| 203 | * to be collated with their norminal form. For example, the half-width and |
| 204 | * full-width ASCII and Katakana characters are then collated together. |
| 205 | * FULL_DECOMPOSITION is the most complete and therefore the slowest |
| 206 | * decomposition mode. |
| 207 | * <p> |
| 208 | * FULL_DECOMPOSITION corresponds to Normalization Form KD as |
| 209 | * described in |
| 210 | * <a href="http://www.unicode.org/unicode/reports/tr15/tr15-23.html">Unicode |
| 211 | * Technical Report #15</a>. |
| 212 | * @see java.text.Collator#getDecomposition |
| 213 | * @see java.text.Collator#setDecomposition |
| 214 | */ |
| 215 | public final static int FULL_DECOMPOSITION = 2; |
| 216 | |
| 217 | /** |
| 218 | * Gets the Collator for the current default locale. |
| 219 | * The default locale is determined by java.util.Locale.getDefault. |
| 220 | * @return the Collator for the default locale.(for example, en_US) |
| 221 | * @see java.util.Locale#getDefault |
| 222 | */ |
| 223 | public static synchronized Collator getInstance() { |
| 224 | return getInstance(Locale.getDefault()); |
| 225 | } |
| 226 | |
| 227 | /** |
| 228 | * Gets the Collator for the desired locale. |
| 229 | * @param desiredLocale the desired locale. |
| 230 | * @return the Collator for the desired locale. |
| 231 | * @see java.util.Locale |
| 232 | * @see java.util.ResourceBundle |
| 233 | */ |
| 234 | public static synchronized |
| 235 | Collator getInstance(Locale desiredLocale) |
| 236 | { |
| 237 | Collator result = (Collator) cache.get(desiredLocale); |
| 238 | if (result != null) { |
| 239 | return (Collator)result.clone(); // make the world safe |
| 240 | } |
| 241 | |
| 242 | // Check whether a provider can provide an implementation that's closer |
| 243 | // to the requested locale than what the Java runtime itself can provide. |
| 244 | LocaleServiceProviderPool pool = |
| 245 | LocaleServiceProviderPool.getPool(CollatorProvider.class); |
| 246 | if (pool.hasProviders()) { |
| 247 | Collator providersInstance = pool.getLocalizedObject( |
| 248 | CollatorGetter.INSTANCE, |
| 249 | desiredLocale, |
| 250 | desiredLocale); |
| 251 | if (providersInstance != null) { |
| 252 | return providersInstance; |
| 253 | } |
| 254 | } |
| 255 | |
| 256 | // Load the resource of the desired locale from resource |
| 257 | // manager. |
| 258 | String colString = ""; |
| 259 | try { |
| 260 | ResourceBundle resource = LocaleData.getCollationData(desiredLocale); |
| 261 | |
| 262 | colString = resource.getString("Rule"); |
| 263 | } catch (MissingResourceException e) { |
| 264 | // Use default values |
| 265 | } |
| 266 | try |
| 267 | { |
| 268 | result = new RuleBasedCollator( CollationRules.DEFAULTRULES + |
| 269 | colString, |
| 270 | CANONICAL_DECOMPOSITION ); |
| 271 | } |
| 272 | catch(ParseException foo) |
| 273 | { |
| 274 | // predefined tables should contain correct grammar |
| 275 | try { |
| 276 | result = new RuleBasedCollator( CollationRules.DEFAULTRULES ); |
| 277 | } catch (ParseException bar) { |
| 278 | // do nothing |
| 279 | } |
| 280 | } |
| 281 | // Now that RuleBasedCollator adds expansions for pre-composed characters |
| 282 | // into their decomposed equivalents, the default collators don't need |
| 283 | // to have decomposition turned on. Laura, 5/5/98, bug 4114077 |
| 284 | result.setDecomposition(NO_DECOMPOSITION); |
| 285 | |
| 286 | cache.put(desiredLocale,result); |
| 287 | return (Collator)result.clone(); |
| 288 | } |
| 289 | |
| 290 | /** |
| 291 | * Compares the source string to the target string according to the |
| 292 | * collation rules for this Collator. Returns an integer less than, |
| 293 | * equal to or greater than zero depending on whether the source String is |
| 294 | * less than, equal to or greater than the target string. See the Collator |
| 295 | * class description for an example of use. |
| 296 | * <p> |
| 297 | * For a one time comparison, this method has the best performance. If a |
| 298 | * given String will be involved in multiple comparisons, CollationKey.compareTo |
| 299 | * has the best performance. See the Collator class description for an example |
| 300 | * using CollationKeys. |
| 301 | * @param source the source string. |
| 302 | * @param target the target string. |
| 303 | * @return Returns an integer value. Value is less than zero if source is less than |
| 304 | * target, value is zero if source and target are equal, value is greater than zero |
| 305 | * if source is greater than target. |
| 306 | * @see java.text.CollationKey |
| 307 | * @see java.text.Collator#getCollationKey |
| 308 | */ |
| 309 | public abstract int compare(String source, String target); |
| 310 | |
| 311 | /** |
| 312 | * Compares its two arguments for order. Returns a negative integer, |
| 313 | * zero, or a positive integer as the first argument is less than, equal |
| 314 | * to, or greater than the second. |
| 315 | * <p> |
| 316 | * This implementation merely returns |
| 317 | * <code> compare((String)o1, (String)o2) </code>. |
| 318 | * |
| 319 | * @return a negative integer, zero, or a positive integer as the |
| 320 | * first argument is less than, equal to, or greater than the |
| 321 | * second. |
| 322 | * @exception ClassCastException the arguments cannot be cast to Strings. |
| 323 | * @see java.util.Comparator |
| 324 | * @since 1.2 |
| 325 | */ |
| 326 | public int compare(Object o1, Object o2) { |
| 327 | return compare((String)o1, (String)o2); |
| 328 | } |
| 329 | |
| 330 | /** |
| 331 | * Transforms the String into a series of bits that can be compared bitwise |
| 332 | * to other CollationKeys. CollationKeys provide better performance than |
| 333 | * Collator.compare when Strings are involved in multiple comparisons. |
| 334 | * See the Collator class description for an example using CollationKeys. |
| 335 | * @param source the string to be transformed into a collation key. |
| 336 | * @return the CollationKey for the given String based on this Collator's collation |
| 337 | * rules. If the source String is null, a null CollationKey is returned. |
| 338 | * @see java.text.CollationKey |
| 339 | * @see java.text.Collator#compare |
| 340 | */ |
| 341 | public abstract CollationKey getCollationKey(String source); |
| 342 | |
| 343 | /** |
| 344 | * Convenience method for comparing the equality of two strings based on |
| 345 | * this Collator's collation rules. |
| 346 | * @param source the source string to be compared with. |
| 347 | * @param target the target string to be compared with. |
| 348 | * @return true if the strings are equal according to the collation |
| 349 | * rules. false, otherwise. |
| 350 | * @see java.text.Collator#compare |
| 351 | */ |
| 352 | public boolean equals(String source, String target) |
| 353 | { |
| 354 | return (compare(source, target) == Collator.EQUAL); |
| 355 | } |
| 356 | |
| 357 | /** |
| 358 | * Returns this Collator's strength property. The strength property determines |
| 359 | * the minimum level of difference considered significant during comparison. |
| 360 | * See the Collator class description for an example of use. |
| 361 | * @return this Collator's current strength property. |
| 362 | * @see java.text.Collator#setStrength |
| 363 | * @see java.text.Collator#PRIMARY |
| 364 | * @see java.text.Collator#SECONDARY |
| 365 | * @see java.text.Collator#TERTIARY |
| 366 | * @see java.text.Collator#IDENTICAL |
| 367 | */ |
| 368 | public synchronized int getStrength() |
| 369 | { |
| 370 | return strength; |
| 371 | } |
| 372 | |
| 373 | /** |
| 374 | * Sets this Collator's strength property. The strength property determines |
| 375 | * the minimum level of difference considered significant during comparison. |
| 376 | * See the Collator class description for an example of use. |
| 377 | * @param newStrength the new strength value. |
| 378 | * @see java.text.Collator#getStrength |
| 379 | * @see java.text.Collator#PRIMARY |
| 380 | * @see java.text.Collator#SECONDARY |
| 381 | * @see java.text.Collator#TERTIARY |
| 382 | * @see java.text.Collator#IDENTICAL |
| 383 | * @exception IllegalArgumentException If the new strength value is not one of |
| 384 | * PRIMARY, SECONDARY, TERTIARY or IDENTICAL. |
| 385 | */ |
| 386 | public synchronized void setStrength(int newStrength) { |
| 387 | if ((newStrength != PRIMARY) && |
| 388 | (newStrength != SECONDARY) && |
| 389 | (newStrength != TERTIARY) && |
| 390 | (newStrength != IDENTICAL)) |
| 391 | throw new IllegalArgumentException("Incorrect comparison level."); |
| 392 | strength = newStrength; |
| 393 | } |
| 394 | |
| 395 | /** |
| 396 | * Get the decomposition mode of this Collator. Decomposition mode |
| 397 | * determines how Unicode composed characters are handled. Adjusting |
| 398 | * decomposition mode allows the user to select between faster and more |
| 399 | * complete collation behavior. |
| 400 | * <p>The three values for decomposition mode are: |
| 401 | * <UL> |
| 402 | * <LI>NO_DECOMPOSITION, |
| 403 | * <LI>CANONICAL_DECOMPOSITION |
| 404 | * <LI>FULL_DECOMPOSITION. |
| 405 | * </UL> |
| 406 | * See the documentation for these three constants for a description |
| 407 | * of their meaning. |
| 408 | * @return the decomposition mode |
| 409 | * @see java.text.Collator#setDecomposition |
| 410 | * @see java.text.Collator#NO_DECOMPOSITION |
| 411 | * @see java.text.Collator#CANONICAL_DECOMPOSITION |
| 412 | * @see java.text.Collator#FULL_DECOMPOSITION |
| 413 | */ |
| 414 | public synchronized int getDecomposition() |
| 415 | { |
| 416 | return decmp; |
| 417 | } |
| 418 | /** |
| 419 | * Set the decomposition mode of this Collator. See getDecomposition |
| 420 | * for a description of decomposition mode. |
| 421 | * @param decompositionMode the new decomposition mode. |
| 422 | * @see java.text.Collator#getDecomposition |
| 423 | * @see java.text.Collator#NO_DECOMPOSITION |
| 424 | * @see java.text.Collator#CANONICAL_DECOMPOSITION |
| 425 | * @see java.text.Collator#FULL_DECOMPOSITION |
| 426 | * @exception IllegalArgumentException If the given value is not a valid decomposition |
| 427 | * mode. |
| 428 | */ |
| 429 | public synchronized void setDecomposition(int decompositionMode) { |
| 430 | if ((decompositionMode != NO_DECOMPOSITION) && |
| 431 | (decompositionMode != CANONICAL_DECOMPOSITION) && |
| 432 | (decompositionMode != FULL_DECOMPOSITION)) |
| 433 | throw new IllegalArgumentException("Wrong decomposition mode."); |
| 434 | decmp = decompositionMode; |
| 435 | } |
| 436 | |
| 437 | /** |
| 438 | * Returns an array of all locales for which the |
| 439 | * <code>getInstance</code> methods of this class can return |
| 440 | * localized instances. |
| 441 | * The returned array represents the union of locales supported |
| 442 | * by the Java runtime and by installed |
| 443 | * {@link java.text.spi.CollatorProvider CollatorProvider} implementations. |
| 444 | * It must contain at least a Locale instance equal to |
| 445 | * {@link java.util.Locale#US Locale.US}. |
| 446 | * |
| 447 | * @return An array of locales for which localized |
| 448 | * <code>Collator</code> instances are available. |
| 449 | */ |
| 450 | public static synchronized Locale[] getAvailableLocales() { |
| 451 | LocaleServiceProviderPool pool = |
| 452 | LocaleServiceProviderPool.getPool(CollatorProvider.class); |
| 453 | return pool.getAvailableLocales(); |
| 454 | } |
| 455 | |
| 456 | /** |
| 457 | * Overrides Cloneable |
| 458 | */ |
| 459 | public Object clone() |
| 460 | { |
| 461 | try { |
| 462 | return (Collator)super.clone(); |
| 463 | } catch (CloneNotSupportedException e) { |
| 464 | throw new InternalError(); |
| 465 | } |
| 466 | } |
| 467 | |
| 468 | /** |
| 469 | * Compares the equality of two Collators. |
| 470 | * @param that the Collator to be compared with this. |
| 471 | * @return true if this Collator is the same as that Collator; |
| 472 | * false otherwise. |
| 473 | */ |
| 474 | public boolean equals(Object that) |
| 475 | { |
| 476 | if (this == that) return true; |
| 477 | if (that == null) return false; |
| 478 | if (getClass() != that.getClass()) return false; |
| 479 | Collator other = (Collator) that; |
| 480 | return ((strength == other.strength) && |
| 481 | (decmp == other.decmp)); |
| 482 | } |
| 483 | |
| 484 | /** |
| 485 | * Generates the hash code for this Collator. |
| 486 | */ |
| 487 | abstract public int hashCode(); |
| 488 | |
| 489 | /** |
| 490 | * Default constructor. This constructor is |
| 491 | * protected so subclasses can get access to it. Users typically create |
| 492 | * a Collator sub-class by calling the factory method getInstance. |
| 493 | * @see java.text.Collator#getInstance |
| 494 | */ |
| 495 | protected Collator() |
| 496 | { |
| 497 | strength = TERTIARY; |
| 498 | decmp = CANONICAL_DECOMPOSITION; |
| 499 | } |
| 500 | |
| 501 | private int strength = 0; |
| 502 | private int decmp = 0; |
| 503 | private static SoftCache cache = new SoftCache(); |
| 504 | |
| 505 | // |
| 506 | // FIXME: These three constants should be removed. |
| 507 | // |
| 508 | /** |
| 509 | * LESS is returned if source string is compared to be less than target |
| 510 | * string in the compare() method. |
| 511 | * @see java.text.Collator#compare |
| 512 | */ |
| 513 | final static int LESS = -1; |
| 514 | /** |
| 515 | * EQUAL is returned if source string is compared to be equal to target |
| 516 | * string in the compare() method. |
| 517 | * @see java.text.Collator#compare |
| 518 | */ |
| 519 | final static int EQUAL = 0; |
| 520 | /** |
| 521 | * GREATER is returned if source string is compared to be greater than |
| 522 | * target string in the compare() method. |
| 523 | * @see java.text.Collator#compare |
| 524 | */ |
| 525 | final static int GREATER = 1; |
| 526 | |
| 527 | /** |
| 528 | * Obtains a Collator instance from a CollatorProvider |
| 529 | * implementation. |
| 530 | */ |
| 531 | private static class CollatorGetter |
| 532 | implements LocaleServiceProviderPool.LocalizedObjectGetter<CollatorProvider, Collator> { |
| 533 | private static final CollatorGetter INSTANCE = new CollatorGetter(); |
| 534 | |
| 535 | public Collator getObject(CollatorProvider collatorProvider, |
| 536 | Locale locale, |
| 537 | String key, |
| 538 | Object... params) { |
| 539 | assert params.length == 1; |
| 540 | Collator result = collatorProvider.getInstance(locale); |
| 541 | if (result != null) { |
| 542 | // put this Collator instance in the cache for two locales, one |
| 543 | // is for the desired locale, and the other is for the actual |
| 544 | // locale where the provider is found, which may be a fall back locale. |
| 545 | cache.put((Locale)params[0], result); |
| 546 | cache.put(locale, result); |
| 547 | return (Collator)result.clone(); |
| 548 | } |
| 549 | |
| 550 | return null; |
| 551 | } |
| 552 | } |
| 553 | } |