1 /* 2 * Copyright (c) 1996, 2012, Oracle and/or its affiliates. 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. Oracle designates this 8 * particular file as subject to the "Classpath" exception as provided 9 * by Oracle 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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 22 * or visit www.oracle.com if you need additional information or have any 23 * questions. 24 */ 25 26 /* 27 * (C) Copyright Taligent, Inc. 1996, 1997 - All Rights Reserved 28 * (C) Copyright IBM Corp. 1996 - 1999 - All Rights Reserved 29 * 30 * The original version of this source code and documentation 31 * is copyrighted and owned by Taligent, Inc., a wholly-owned 32 * subsidiary of IBM. These materials are provided under terms 33 * of a License Agreement between Taligent and Sun. This technology 34 * is protected by multiple US and International patents. 35 * 36 * This notice and attribution to Taligent may not be removed. 37 * Taligent is a registered trademark of Taligent, Inc. 38 * 39 */ 40 41 package java.util; 42 43 import java.io.IOException; 44 import java.io.InputStream; 45 import java.lang.ref.ReferenceQueue; 46 import java.lang.ref.SoftReference; 47 import java.lang.ref.WeakReference; 48 import java.net.JarURLConnection; 49 import java.net.URL; 50 import java.net.URLConnection; 51 import java.security.AccessController; 52 import java.security.PrivilegedAction; 53 import java.security.PrivilegedActionException; 54 import java.security.PrivilegedExceptionAction; 55 import java.util.concurrent.ConcurrentHashMap; 56 import java.util.concurrent.ConcurrentMap; 57 import java.util.jar.JarEntry; 58 import java.util.spi.ResourceBundleControlProvider; 59 60 import sun.reflect.CallerSensitive; 61 import sun.reflect.Reflection; 62 import sun.util.locale.BaseLocale; 63 import sun.util.locale.LocaleObjectCache; 64 65 66 /** 67 * 68 * Resource bundles contain locale-specific objects. When your program needs a 69 * locale-specific resource, a <code>String</code> for example, your program can 70 * load it from the resource bundle that is appropriate for the current user's 71 * locale. In this way, you can write program code that is largely independent 72 * of the user's locale isolating most, if not all, of the locale-specific 73 * information in resource bundles. 74 * 75 * <p> 76 * This allows you to write programs that can: 77 * <UL type=SQUARE> 78 * <LI> be easily localized, or translated, into different languages 79 * <LI> handle multiple locales at once 80 * <LI> be easily modified later to support even more locales 81 * </UL> 82 * 83 * <P> 84 * Resource bundles belong to families whose members share a common base 85 * name, but whose names also have additional components that identify 86 * their locales. For example, the base name of a family of resource 87 * bundles might be "MyResources". The family should have a default 88 * resource bundle which simply has the same name as its family - 89 * "MyResources" - and will be used as the bundle of last resort if a 90 * specific locale is not supported. The family can then provide as 91 * many locale-specific members as needed, for example a German one 92 * named "MyResources_de". 93 * 94 * <P> 95 * Each resource bundle in a family contains the same items, but the items have 96 * been translated for the locale represented by that resource bundle. 97 * For example, both "MyResources" and "MyResources_de" may have a 98 * <code>String</code> that's used on a button for canceling operations. 99 * In "MyResources" the <code>String</code> may contain "Cancel" and in 100 * "MyResources_de" it may contain "Abbrechen". 101 * 102 * <P> 103 * If there are different resources for different countries, you 104 * can make specializations: for example, "MyResources_de_CH" contains objects for 105 * the German language (de) in Switzerland (CH). If you want to only 106 * modify some of the resources 107 * in the specialization, you can do so. 108 * 109 * <P> 110 * When your program needs a locale-specific object, it loads 111 * the <code>ResourceBundle</code> class using the 112 * {@link #getBundle(java.lang.String, java.util.Locale) getBundle} 113 * method: 114 * <blockquote> 115 * <pre> 116 * ResourceBundle myResources = 117 * ResourceBundle.getBundle("MyResources", currentLocale); 118 * </pre> 119 * </blockquote> 120 * 121 * <P> 122 * Resource bundles contain key/value pairs. The keys uniquely 123 * identify a locale-specific object in the bundle. Here's an 124 * example of a <code>ListResourceBundle</code> that contains 125 * two key/value pairs: 126 * <blockquote> 127 * <pre> 128 * public class MyResources extends ListResourceBundle { 129 * protected Object[][] getContents() { 130 * return new Object[][] { 131 * // LOCALIZE THE SECOND STRING OF EACH ARRAY (e.g., "OK") 132 * {"OkKey", "OK"}, 133 * {"CancelKey", "Cancel"}, 134 * // END OF MATERIAL TO LOCALIZE 135 * }; 136 * } 137 * } 138 * </pre> 139 * </blockquote> 140 * Keys are always <code>String</code>s. 141 * In this example, the keys are "OkKey" and "CancelKey". 142 * In the above example, the values 143 * are also <code>String</code>s--"OK" and "Cancel"--but 144 * they don't have to be. The values can be any type of object. 145 * 146 * <P> 147 * You retrieve an object from resource bundle using the appropriate 148 * getter method. Because "OkKey" and "CancelKey" 149 * are both strings, you would use <code>getString</code> to retrieve them: 150 * <blockquote> 151 * <pre> 152 * button1 = new Button(myResources.getString("OkKey")); 153 * button2 = new Button(myResources.getString("CancelKey")); 154 * </pre> 155 * </blockquote> 156 * The getter methods all require the key as an argument and return 157 * the object if found. If the object is not found, the getter method 158 * throws a <code>MissingResourceException</code>. 159 * 160 * <P> 161 * Besides <code>getString</code>, <code>ResourceBundle</code> also provides 162 * a method for getting string arrays, <code>getStringArray</code>, 163 * as well as a generic <code>getObject</code> method for any other 164 * type of object. When using <code>getObject</code>, you'll 165 * have to cast the result to the appropriate type. For example: 166 * <blockquote> 167 * <pre> 168 * int[] myIntegers = (int[]) myResources.getObject("intList"); 169 * </pre> 170 * </blockquote> 171 * 172 * <P> 173 * The Java Platform provides two subclasses of <code>ResourceBundle</code>, 174 * <code>ListResourceBundle</code> and <code>PropertyResourceBundle</code>, 175 * that provide a fairly simple way to create resources. 176 * As you saw briefly in a previous example, <code>ListResourceBundle</code> 177 * manages its resource as a list of key/value pairs. 178 * <code>PropertyResourceBundle</code> uses a properties file to manage 179 * its resources. 180 * 181 * <p> 182 * If <code>ListResourceBundle</code> or <code>PropertyResourceBundle</code> 183 * do not suit your needs, you can write your own <code>ResourceBundle</code> 184 * subclass. Your subclasses must override two methods: <code>handleGetObject</code> 185 * and <code>getKeys()</code>. 186 * 187 * <h4>ResourceBundle.Control</h4> 188 * 189 * The {@link ResourceBundle.Control} class provides information necessary 190 * to perform the bundle loading process by the <code>getBundle</code> 191 * factory methods that take a <code>ResourceBundle.Control</code> 192 * instance. You can implement your own subclass in order to enable 193 * non-standard resource bundle formats, change the search strategy, or 194 * define caching parameters. Refer to the descriptions of the class and the 195 * {@link #getBundle(String, Locale, ClassLoader, Control) getBundle} 196 * factory method for details. 197 * 198 * <p><a name="modify_default_behavior">For the {@code getBundle} factory 199 * methods that take no {@link Control} instance, their <a 200 * href="#default_behavior"> default behavior</a> of resource bundle loading 201 * can be modified with <em>installed</em> {@link 202 * ResourceBundleControlProvider} implementations. Any installed providers are 203 * detected at the {@code ResourceBundle} class loading time. If any of the 204 * providers provides a {@link Control} for the given base name, that {@link 205 * Control} will be used instead of the default {@link Control}. If there is 206 * more than one service provider installed for supporting the same base name, 207 * the first one returned from {@link ServiceLoader} will be used. 208 * 209 * <h4>Cache Management</h4> 210 * 211 * Resource bundle instances created by the <code>getBundle</code> factory 212 * methods are cached by default, and the factory methods return the same 213 * resource bundle instance multiple times if it has been 214 * cached. <code>getBundle</code> clients may clear the cache, manage the 215 * lifetime of cached resource bundle instances using time-to-live values, 216 * or specify not to cache resource bundle instances. Refer to the 217 * descriptions of the {@linkplain #getBundle(String, Locale, ClassLoader, 218 * Control) <code>getBundle</code> factory method}, {@link 219 * #clearCache(ClassLoader) clearCache}, {@link 220 * Control#getTimeToLive(String, Locale) 221 * ResourceBundle.Control.getTimeToLive}, and {@link 222 * Control#needsReload(String, Locale, String, ClassLoader, ResourceBundle, 223 * long) ResourceBundle.Control.needsReload} for details. 224 * 225 * <h4>Example</h4> 226 * 227 * The following is a very simple example of a <code>ResourceBundle</code> 228 * subclass, <code>MyResources</code>, that manages two resources (for a larger number of 229 * resources you would probably use a <code>Map</code>). 230 * Notice that you don't need to supply a value if 231 * a "parent-level" <code>ResourceBundle</code> handles the same 232 * key with the same value (as for the okKey below). 233 * <blockquote> 234 * <pre> 235 * // default (English language, United States) 236 * public class MyResources extends ResourceBundle { 237 * public Object handleGetObject(String key) { 238 * if (key.equals("okKey")) return "Ok"; 239 * if (key.equals("cancelKey")) return "Cancel"; 240 * return null; 241 * } 242 * 243 * public Enumeration<String> getKeys() { 244 * return Collections.enumeration(keySet()); 245 * } 246 * 247 * // Overrides handleKeySet() so that the getKeys() implementation 248 * // can rely on the keySet() value. 249 * protected Set<String> handleKeySet() { 250 * return new HashSet<String>(Arrays.asList("okKey", "cancelKey")); 251 * } 252 * } 253 * 254 * // German language 255 * public class MyResources_de extends MyResources { 256 * public Object handleGetObject(String key) { 257 * // don't need okKey, since parent level handles it. 258 * if (key.equals("cancelKey")) return "Abbrechen"; 259 * return null; 260 * } 261 * 262 * protected Set<String> handleKeySet() { 263 * return new HashSet<String>(Arrays.asList("cancelKey")); 264 * } 265 * } 266 * </pre> 267 * </blockquote> 268 * You do not have to restrict yourself to using a single family of 269 * <code>ResourceBundle</code>s. For example, you could have a set of bundles for 270 * exception messages, <code>ExceptionResources</code> 271 * (<code>ExceptionResources_fr</code>, <code>ExceptionResources_de</code>, ...), 272 * and one for widgets, <code>WidgetResource</code> (<code>WidgetResources_fr</code>, 273 * <code>WidgetResources_de</code>, ...); breaking up the resources however you like. 274 * 275 * @see ListResourceBundle 276 * @see PropertyResourceBundle 277 * @see MissingResourceException 278 * @since JDK1.1 279 */ 280 public abstract class ResourceBundle { 281 282 /** initial size of the bundle cache */ 283 private static final int INITIAL_CACHE_SIZE = 32; 284 285 /** constant indicating that no resource bundle exists */ 286 private static final ResourceBundle NONEXISTENT_BUNDLE = new ResourceBundle() { 287 public Enumeration<String> getKeys() { return null; } 288 protected Object handleGetObject(String key) { return null; } 289 public String toString() { return "NONEXISTENT_BUNDLE"; } 290 }; 291 292 293 /** 294 * The cache is a map from cache keys (with bundle base name, locale, and 295 * class loader) to either a resource bundle or NONEXISTENT_BUNDLE wrapped by a 296 * BundleReference. 297 * 298 * The cache is a ConcurrentMap, allowing the cache to be searched 299 * concurrently by multiple threads. This will also allow the cache keys 300 * to be reclaimed along with the ClassLoaders they reference. 301 * 302 * This variable would be better named "cache", but we keep the old 303 * name for compatibility with some workarounds for bug 4212439. 304 */ 305 private static final ConcurrentMap<CacheKey, BundleReference> cacheList 306 = new ConcurrentHashMap<>(INITIAL_CACHE_SIZE); 307 308 /** 309 * Queue for reference objects referring to class loaders or bundles. 310 */ 311 private static final ReferenceQueue<Object> referenceQueue = new ReferenceQueue<>(); 312 313 /** 314 * The parent bundle of this bundle. 315 * The parent bundle is searched by {@link #getObject getObject} 316 * when this bundle does not contain a particular resource. 317 */ 318 protected ResourceBundle parent = null; 319 320 /** 321 * The locale for this bundle. 322 */ 323 private Locale locale = null; 324 325 /** 326 * The base bundle name for this bundle. 327 */ 328 private String name; 329 330 /** 331 * The flag indicating this bundle has expired in the cache. 332 */ 333 private volatile boolean expired; 334 335 /** 336 * The back link to the cache key. null if this bundle isn't in 337 * the cache (yet) or has expired. 338 */ 339 private volatile CacheKey cacheKey; 340 341 /** 342 * A Set of the keys contained only in this ResourceBundle. 343 */ 344 private volatile Set<String> keySet; 345 346 private static final List<ResourceBundleControlProvider> providers; 347 348 static { 349 List<ResourceBundleControlProvider> list = null; 350 ServiceLoader<ResourceBundleControlProvider> serviceLoaders 351 = ServiceLoader.loadInstalled(ResourceBundleControlProvider.class); 352 for (ResourceBundleControlProvider provider : serviceLoaders) { 353 if (list == null) { 354 list = new ArrayList<>(); 355 } 356 list.add(provider); 357 } 358 providers = list; 359 } 360 361 /** 362 * Sole constructor. (For invocation by subclass constructors, typically 363 * implicit.) 364 */ 365 public ResourceBundle() { 366 } 367 368 /** 369 * Gets a string for the given key from this resource bundle or one of its parents. 370 * Calling this method is equivalent to calling 371 * <blockquote> 372 * <code>(String) {@link #getObject(java.lang.String) getObject}(key)</code>. 373 * </blockquote> 374 * 375 * @param key the key for the desired string 376 * @exception NullPointerException if <code>key</code> is <code>null</code> 377 * @exception MissingResourceException if no object for the given key can be found 378 * @exception ClassCastException if the object found for the given key is not a string 379 * @return the string for the given key 380 */ 381 public final String getString(String key) { 382 return (String) getObject(key); 383 } 384 385 /** 386 * Gets a string array for the given key from this resource bundle or one of its parents. 387 * Calling this method is equivalent to calling 388 * <blockquote> 389 * <code>(String[]) {@link #getObject(java.lang.String) getObject}(key)</code>. 390 * </blockquote> 391 * 392 * @param key the key for the desired string array 393 * @exception NullPointerException if <code>key</code> is <code>null</code> 394 * @exception MissingResourceException if no object for the given key can be found 395 * @exception ClassCastException if the object found for the given key is not a string array 396 * @return the string array for the given key 397 */ 398 public final String[] getStringArray(String key) { 399 return (String[]) getObject(key); 400 } 401 402 /** 403 * Gets an object for the given key from this resource bundle or one of its parents. 404 * This method first tries to obtain the object from this resource bundle using 405 * {@link #handleGetObject(java.lang.String) handleGetObject}. 406 * If not successful, and the parent resource bundle is not null, 407 * it calls the parent's <code>getObject</code> method. 408 * If still not successful, it throws a MissingResourceException. 409 * 410 * @param key the key for the desired object 411 * @exception NullPointerException if <code>key</code> is <code>null</code> 412 * @exception MissingResourceException if no object for the given key can be found 413 * @return the object for the given key 414 */ 415 public final Object getObject(String key) { 416 Object obj = handleGetObject(key); 417 if (obj == null) { 418 if (parent != null) { 419 obj = parent.getObject(key); 420 } 421 if (obj == null) { 422 throw new MissingResourceException("Can't find resource for bundle " 423 +this.getClass().getName() 424 +", key "+key, 425 this.getClass().getName(), 426 key); 427 } 428 } 429 return obj; 430 } 431 432 /** 433 * Returns the locale of this resource bundle. This method can be used after a 434 * call to getBundle() to determine whether the resource bundle returned really 435 * corresponds to the requested locale or is a fallback. 436 * 437 * @return the locale of this resource bundle 438 */ 439 public Locale getLocale() { 440 return locale; 441 } 442 443 /* 444 * Automatic determination of the ClassLoader to be used to load 445 * resources on behalf of the client. 446 */ 447 private static ClassLoader getLoader(Class<?> caller) { 448 ClassLoader cl = caller == null ? null : caller.getClassLoader(); 449 if (cl == null) { 450 // When the caller's loader is the boot class loader, cl is null 451 // here. In that case, ClassLoader.getSystemClassLoader() may 452 // return the same class loader that the application is 453 // using. We therefore use a wrapper ClassLoader to create a 454 // separate scope for bundles loaded on behalf of the Java 455 // runtime so that these bundles cannot be returned from the 456 // cache to the application (5048280). 457 cl = RBClassLoader.INSTANCE; 458 } 459 return cl; 460 } 461 462 /** 463 * A wrapper of ClassLoader.getSystemClassLoader(). 464 */ 465 private static class RBClassLoader extends ClassLoader { 466 private static final RBClassLoader INSTANCE = AccessController.doPrivileged( 467 new PrivilegedAction<RBClassLoader>() { 468 public RBClassLoader run() { 469 return new RBClassLoader(); 470 } 471 }); 472 private static final ClassLoader loader = ClassLoader.getSystemClassLoader(); 473 474 private RBClassLoader() { 475 } 476 public Class<?> loadClass(String name) throws ClassNotFoundException { 477 if (loader != null) { 478 return loader.loadClass(name); 479 } 480 return Class.forName(name); 481 } 482 public URL getResource(String name) { 483 if (loader != null) { 484 return loader.getResource(name); 485 } 486 return ClassLoader.getSystemResource(name); 487 } 488 public InputStream getResourceAsStream(String name) { 489 if (loader != null) { 490 return loader.getResourceAsStream(name); 491 } 492 return ClassLoader.getSystemResourceAsStream(name); 493 } 494 } 495 496 /** 497 * Sets the parent bundle of this bundle. 498 * The parent bundle is searched by {@link #getObject getObject} 499 * when this bundle does not contain a particular resource. 500 * 501 * @param parent this bundle's parent bundle. 502 */ 503 protected void setParent(ResourceBundle parent) { 504 assert parent != NONEXISTENT_BUNDLE; 505 this.parent = parent; 506 } 507 508 /** 509 * Key used for cached resource bundles. The key checks the base 510 * name, the locale, and the class loader to determine if the 511 * resource is a match to the requested one. The loader may be 512 * null, but the base name and the locale must have a non-null 513 * value. 514 */ 515 private static class CacheKey implements Cloneable { 516 // These three are the actual keys for lookup in Map. 517 private String name; 518 private Locale locale; 519 private LoaderReference loaderRef; 520 521 // bundle format which is necessary for calling 522 // Control.needsReload(). 523 private String format; 524 525 // These time values are in CacheKey so that NONEXISTENT_BUNDLE 526 // doesn't need to be cloned for caching. 527 528 // The time when the bundle has been loaded 529 private volatile long loadTime; 530 531 // The time when the bundle expires in the cache, or either 532 // Control.TTL_DONT_CACHE or Control.TTL_NO_EXPIRATION_CONTROL. 533 private volatile long expirationTime; 534 535 // Placeholder for an error report by a Throwable 536 private Throwable cause; 537 538 // Hash code value cache to avoid recalculating the hash code 539 // of this instance. 540 private int hashCodeCache; 541 542 CacheKey(String baseName, Locale locale, ClassLoader loader) { 543 this.name = baseName; 544 this.locale = locale; 545 if (loader == null) { 546 this.loaderRef = null; 547 } else { 548 loaderRef = new LoaderReference(loader, referenceQueue, this); 549 } 550 calculateHashCode(); 551 } 552 553 String getName() { 554 return name; 555 } 556 557 CacheKey setName(String baseName) { 558 if (!this.name.equals(baseName)) { 559 this.name = baseName; 560 calculateHashCode(); 561 } 562 return this; 563 } 564 565 Locale getLocale() { 566 return locale; 567 } 568 569 CacheKey setLocale(Locale locale) { 570 if (!this.locale.equals(locale)) { 571 this.locale = locale; 572 calculateHashCode(); 573 } 574 return this; 575 } 576 577 ClassLoader getLoader() { 578 return (loaderRef != null) ? loaderRef.get() : null; 579 } 580 581 public boolean equals(Object other) { 582 if (this == other) { 583 return true; 584 } 585 try { 586 final CacheKey otherEntry = (CacheKey)other; 587 //quick check to see if they are not equal 588 if (hashCodeCache != otherEntry.hashCodeCache) { 589 return false; 590 } 591 //are the names the same? 592 if (!name.equals(otherEntry.name)) { 593 return false; 594 } 595 // are the locales the same? 596 if (!locale.equals(otherEntry.locale)) { 597 return false; 598 } 599 //are refs (both non-null) or (both null)? 600 if (loaderRef == null) { 601 return otherEntry.loaderRef == null; 602 } 603 ClassLoader loader = loaderRef.get(); 604 return (otherEntry.loaderRef != null) 605 // with a null reference we can no longer find 606 // out which class loader was referenced; so 607 // treat it as unequal 608 && (loader != null) 609 && (loader == otherEntry.loaderRef.get()); 610 } catch ( NullPointerException | ClassCastException e) { 611 } 612 return false; 613 } 614 615 public int hashCode() { 616 return hashCodeCache; 617 } 618 619 private void calculateHashCode() { 620 hashCodeCache = name.hashCode() << 3; 621 hashCodeCache ^= locale.hashCode(); 622 ClassLoader loader = getLoader(); 623 if (loader != null) { 624 hashCodeCache ^= loader.hashCode(); 625 } 626 } 627 628 public Object clone() { 629 try { 630 CacheKey clone = (CacheKey) super.clone(); 631 if (loaderRef != null) { 632 clone.loaderRef = new LoaderReference(loaderRef.get(), 633 referenceQueue, clone); 634 } 635 // Clear the reference to a Throwable 636 clone.cause = null; 637 return clone; 638 } catch (CloneNotSupportedException e) { 639 //this should never happen 640 throw new InternalError(e); 641 } 642 } 643 644 String getFormat() { 645 return format; 646 } 647 648 void setFormat(String format) { 649 this.format = format; 650 } 651 652 private void setCause(Throwable cause) { 653 if (this.cause == null) { 654 this.cause = cause; 655 } else { 656 // Override the cause if the previous one is 657 // ClassNotFoundException. 658 if (this.cause instanceof ClassNotFoundException) { 659 this.cause = cause; 660 } 661 } 662 } 663 664 private Throwable getCause() { 665 return cause; 666 } 667 668 public String toString() { 669 String l = locale.toString(); 670 if (l.length() == 0) { 671 if (locale.getVariant().length() != 0) { 672 l = "__" + locale.getVariant(); 673 } else { 674 l = "\"\""; 675 } 676 } 677 return "CacheKey[" + name + ", lc=" + l + ", ldr=" + getLoader() 678 + "(format=" + format + ")]"; 679 } 680 } 681 682 /** 683 * The common interface to get a CacheKey in LoaderReference and 684 * BundleReference. 685 */ 686 private static interface CacheKeyReference { 687 public CacheKey getCacheKey(); 688 } 689 690 /** 691 * References to class loaders are weak references, so that they can be 692 * garbage collected when nobody else is using them. The ResourceBundle 693 * class has no reason to keep class loaders alive. 694 */ 695 private static class LoaderReference extends WeakReference<ClassLoader> 696 implements CacheKeyReference { 697 private CacheKey cacheKey; 698 699 LoaderReference(ClassLoader referent, ReferenceQueue<Object> q, CacheKey key) { 700 super(referent, q); 701 cacheKey = key; 702 } 703 704 public CacheKey getCacheKey() { 705 return cacheKey; 706 } 707 } 708 709 /** 710 * References to bundles are soft references so that they can be garbage 711 * collected when they have no hard references. 712 */ 713 private static class BundleReference extends SoftReference<ResourceBundle> 714 implements CacheKeyReference { 715 private CacheKey cacheKey; 716 717 BundleReference(ResourceBundle referent, ReferenceQueue<Object> q, CacheKey key) { 718 super(referent, q); 719 cacheKey = key; 720 } 721 722 public CacheKey getCacheKey() { 723 return cacheKey; 724 } 725 } 726 727 /** 728 * Gets a resource bundle using the specified base name, the default locale, 729 * and the caller's class loader. Calling this method is equivalent to calling 730 * <blockquote> 731 * <code>getBundle(baseName, Locale.getDefault(), this.getClass().getClassLoader())</code>, 732 * </blockquote> 733 * except that <code>getClassLoader()</code> is run with the security 734 * privileges of <code>ResourceBundle</code>. 735 * See {@link #getBundle(String, Locale, ClassLoader) getBundle} 736 * for a complete description of the search and instantiation strategy. 737 * 738 * @param baseName the base name of the resource bundle, a fully qualified class name 739 * @exception java.lang.NullPointerException 740 * if <code>baseName</code> is <code>null</code> 741 * @exception MissingResourceException 742 * if no resource bundle for the specified base name can be found 743 * @return a resource bundle for the given base name and the default locale 744 */ 745 @CallerSensitive 746 public static final ResourceBundle getBundle(String baseName) 747 { 748 return getBundleImpl(baseName, Locale.getDefault(), 749 getLoader(Reflection.getCallerClass()), 750 getDefaultControl(baseName)); 751 } 752 753 /** 754 * Returns a resource bundle using the specified base name, the 755 * default locale and the specified control. Calling this method 756 * is equivalent to calling 757 * <pre> 758 * getBundle(baseName, Locale.getDefault(), 759 * this.getClass().getClassLoader(), control), 760 * </pre> 761 * except that <code>getClassLoader()</code> is run with the security 762 * privileges of <code>ResourceBundle</code>. See {@link 763 * #getBundle(String, Locale, ClassLoader, Control) getBundle} for the 764 * complete description of the resource bundle loading process with a 765 * <code>ResourceBundle.Control</code>. 766 * 767 * @param baseName 768 * the base name of the resource bundle, a fully qualified class 769 * name 770 * @param control 771 * the control which gives information for the resource bundle 772 * loading process 773 * @return a resource bundle for the given base name and the default 774 * locale 775 * @exception NullPointerException 776 * if <code>baseName</code> or <code>control</code> is 777 * <code>null</code> 778 * @exception MissingResourceException 779 * if no resource bundle for the specified base name can be found 780 * @exception IllegalArgumentException 781 * if the given <code>control</code> doesn't perform properly 782 * (e.g., <code>control.getCandidateLocales</code> returns null.) 783 * Note that validation of <code>control</code> is performed as 784 * needed. 785 * @since 1.6 786 */ 787 @CallerSensitive 788 public static final ResourceBundle getBundle(String baseName, 789 Control control) { 790 return getBundleImpl(baseName, Locale.getDefault(), 791 getLoader(Reflection.getCallerClass()), 792 control); 793 } 794 795 /** 796 * Gets a resource bundle using the specified base name and locale, 797 * and the caller's class loader. Calling this method is equivalent to calling 798 * <blockquote> 799 * <code>getBundle(baseName, locale, this.getClass().getClassLoader())</code>, 800 * </blockquote> 801 * except that <code>getClassLoader()</code> is run with the security 802 * privileges of <code>ResourceBundle</code>. 803 * See {@link #getBundle(String, Locale, ClassLoader) getBundle} 804 * for a complete description of the search and instantiation strategy. 805 * 806 * @param baseName 807 * the base name of the resource bundle, a fully qualified class name 808 * @param locale 809 * the locale for which a resource bundle is desired 810 * @exception NullPointerException 811 * if <code>baseName</code> or <code>locale</code> is <code>null</code> 812 * @exception MissingResourceException 813 * if no resource bundle for the specified base name can be found 814 * @return a resource bundle for the given base name and locale 815 */ 816 @CallerSensitive 817 public static final ResourceBundle getBundle(String baseName, 818 Locale locale) 819 { 820 return getBundleImpl(baseName, locale, 821 getLoader(Reflection.getCallerClass()), 822 getDefaultControl(baseName)); 823 } 824 825 /** 826 * Returns a resource bundle using the specified base name, target 827 * locale and control, and the caller's class loader. Calling this 828 * method is equivalent to calling 829 * <pre> 830 * getBundle(baseName, targetLocale, this.getClass().getClassLoader(), 831 * control), 832 * </pre> 833 * except that <code>getClassLoader()</code> is run with the security 834 * privileges of <code>ResourceBundle</code>. See {@link 835 * #getBundle(String, Locale, ClassLoader, Control) getBundle} for the 836 * complete description of the resource bundle loading process with a 837 * <code>ResourceBundle.Control</code>. 838 * 839 * @param baseName 840 * the base name of the resource bundle, a fully qualified 841 * class name 842 * @param targetLocale 843 * the locale for which a resource bundle is desired 844 * @param control 845 * the control which gives information for the resource 846 * bundle loading process 847 * @return a resource bundle for the given base name and a 848 * <code>Locale</code> in <code>locales</code> 849 * @exception NullPointerException 850 * if <code>baseName</code>, <code>locales</code> or 851 * <code>control</code> is <code>null</code> 852 * @exception MissingResourceException 853 * if no resource bundle for the specified base name in any 854 * of the <code>locales</code> can be found. 855 * @exception IllegalArgumentException 856 * if the given <code>control</code> doesn't perform properly 857 * (e.g., <code>control.getCandidateLocales</code> returns null.) 858 * Note that validation of <code>control</code> is performed as 859 * needed. 860 * @since 1.6 861 */ 862 @CallerSensitive 863 public static final ResourceBundle getBundle(String baseName, Locale targetLocale, 864 Control control) { 865 return getBundleImpl(baseName, targetLocale, 866 getLoader(Reflection.getCallerClass()), 867 control); 868 } 869 870 /** 871 * Gets a resource bundle using the specified base name, locale, and class 872 * loader. 873 * 874 * <p>This method behaves the same as calling 875 * {@link #getBundle(String, Locale, ClassLoader, Control)} passing a 876 * default instance of {@link Control} unless another {@link Control} is 877 * provided with the {@link ResourceBundleControlProvider} SPI. Refer to the 878 * description of <a href="#modify_default_behavior">modifying the default 879 * behavior</a>. 880 * 881 * <p><a name="default_behavior"/>The following describes the default 882 * behavior. 883 * 884 * <p><code>getBundle</code> uses the base name, the specified locale, and 885 * the default locale (obtained from {@link java.util.Locale#getDefault() 886 * Locale.getDefault}) to generate a sequence of <a 887 * name="candidates"><em>candidate bundle names</em></a>. If the specified 888 * locale's language, script, country, and variant are all empty strings, 889 * then the base name is the only candidate bundle name. Otherwise, a list 890 * of candidate locales is generated from the attribute values of the 891 * specified locale (language, script, country and variant) and appended to 892 * the base name. Typically, this will look like the following: 893 * 894 * <pre> 895 * baseName + "_" + language + "_" + script + "_" + country + "_" + variant 896 * baseName + "_" + language + "_" + script + "_" + country 897 * baseName + "_" + language + "_" + script 898 * baseName + "_" + language + "_" + country + "_" + variant 899 * baseName + "_" + language + "_" + country 900 * baseName + "_" + language 901 * </pre> 902 * 903 * <p>Candidate bundle names where the final component is an empty string 904 * are omitted, along with the underscore. For example, if country is an 905 * empty string, the second and the fifth candidate bundle names above 906 * would be omitted. Also, if script is an empty string, the candidate names 907 * including script are omitted. For example, a locale with language "de" 908 * and variant "JAVA" will produce candidate names with base name 909 * "MyResource" below. 910 * 911 * <pre> 912 * MyResource_de__JAVA 913 * MyResource_de 914 * </pre> 915 * 916 * In the case that the variant contains one or more underscores ('_'), a 917 * sequence of bundle names generated by truncating the last underscore and 918 * the part following it is inserted after a candidate bundle name with the 919 * original variant. For example, for a locale with language "en", script 920 * "Latn, country "US" and variant "WINDOWS_VISTA", and bundle base name 921 * "MyResource", the list of candidate bundle names below is generated: 922 * 923 * <pre> 924 * MyResource_en_Latn_US_WINDOWS_VISTA 925 * MyResource_en_Latn_US_WINDOWS 926 * MyResource_en_Latn_US 927 * MyResource_en_Latn 928 * MyResource_en_US_WINDOWS_VISTA 929 * MyResource_en_US_WINDOWS 930 * MyResource_en_US 931 * MyResource_en 932 * </pre> 933 * 934 * <blockquote><b>Note:</b> For some <code>Locale</code>s, the list of 935 * candidate bundle names contains extra names, or the order of bundle names 936 * is slightly modified. See the description of the default implementation 937 * of {@link Control#getCandidateLocales(String, Locale) 938 * getCandidateLocales} for details.</blockquote> 939 * 940 * <p><code>getBundle</code> then iterates over the candidate bundle names 941 * to find the first one for which it can <em>instantiate</em> an actual 942 * resource bundle. It uses the default controls' {@link Control#getFormats 943 * getFormats} method, which generates two bundle names for each generated 944 * name, the first a class name and the second a properties file name. For 945 * each candidate bundle name, it attempts to create a resource bundle: 946 * 947 * <ul><li>First, it attempts to load a class using the generated class name. 948 * If such a class can be found and loaded using the specified class 949 * loader, is assignment compatible with ResourceBundle, is accessible from 950 * ResourceBundle, and can be instantiated, <code>getBundle</code> creates a 951 * new instance of this class and uses it as the <em>result resource 952 * bundle</em>. 953 * 954 * <li>Otherwise, <code>getBundle</code> attempts to locate a property 955 * resource file using the generated properties file name. It generates a 956 * path name from the candidate bundle name by replacing all "." characters 957 * with "/" and appending the string ".properties". It attempts to find a 958 * "resource" with this name using {@link 959 * java.lang.ClassLoader#getResource(java.lang.String) 960 * ClassLoader.getResource}. (Note that a "resource" in the sense of 961 * <code>getResource</code> has nothing to do with the contents of a 962 * resource bundle, it is just a container of data, such as a file.) If it 963 * finds a "resource", it attempts to create a new {@link 964 * PropertyResourceBundle} instance from its contents. If successful, this 965 * instance becomes the <em>result resource bundle</em>. </ul> 966 * 967 * <p>This continues until a result resource bundle is instantiated or the 968 * list of candidate bundle names is exhausted. If no matching resource 969 * bundle is found, the default control's {@link Control#getFallbackLocale 970 * getFallbackLocale} method is called, which returns the current default 971 * locale. A new sequence of candidate locale names is generated using this 972 * locale and and searched again, as above. 973 * 974 * <p>If still no result bundle is found, the base name alone is looked up. If 975 * this still fails, a <code>MissingResourceException</code> is thrown. 976 * 977 * <p><a name="parent_chain"/> Once a result resource bundle has been found, 978 * its <em>parent chain</em> is instantiated. If the result bundle already 979 * has a parent (perhaps because it was returned from a cache) the chain is 980 * complete. 981 * 982 * <p>Otherwise, <code>getBundle</code> examines the remainder of the 983 * candidate locale list that was used during the pass that generated the 984 * result resource bundle. (As before, candidate bundle names where the 985 * final component is an empty string are omitted.) When it comes to the 986 * end of the candidate list, it tries the plain bundle name. With each of the 987 * candidate bundle names it attempts to instantiate a resource bundle (first 988 * looking for a class and then a properties file, as described above). 989 * 990 * <p>Whenever it succeeds, it calls the previously instantiated resource 991 * bundle's {@link #setParent(java.util.ResourceBundle) setParent} method 992 * with the new resource bundle. This continues until the list of names 993 * is exhausted or the current bundle already has a non-null parent. 994 * 995 * <p>Once the parent chain is complete, the bundle is returned. 996 * 997 * <p><b>Note:</b> <code>getBundle</code> caches instantiated resource 998 * bundles and might return the same resource bundle instance multiple times. 999 * 1000 * <p><b>Note:</b>The <code>baseName</code> argument should be a fully 1001 * qualified class name. However, for compatibility with earlier versions, 1002 * Sun's Java SE Runtime Environments do not verify this, and so it is 1003 * possible to access <code>PropertyResourceBundle</code>s by specifying a 1004 * path name (using "/") instead of a fully qualified class name (using 1005 * "."). 1006 * 1007 * <p><a name="default_behavior_example"/> 1008 * <strong>Example:</strong> 1009 * <p> 1010 * The following class and property files are provided: 1011 * <pre> 1012 * MyResources.class 1013 * MyResources.properties 1014 * MyResources_fr.properties 1015 * MyResources_fr_CH.class 1016 * MyResources_fr_CH.properties 1017 * MyResources_en.properties 1018 * MyResources_es_ES.class 1019 * </pre> 1020 * 1021 * The contents of all files are valid (that is, public non-abstract 1022 * subclasses of <code>ResourceBundle</code> for the ".class" files, 1023 * syntactically correct ".properties" files). The default locale is 1024 * <code>Locale("en", "GB")</code>. 1025 * 1026 * <p>Calling <code>getBundle</code> with the locale arguments below will 1027 * instantiate resource bundles as follows: 1028 * 1029 * <table> 1030 * <tr><td>Locale("fr", "CH")</td><td>MyResources_fr_CH.class, parent MyResources_fr.properties, parent MyResources.class</td></tr> 1031 * <tr><td>Locale("fr", "FR")</td><td>MyResources_fr.properties, parent MyResources.class</td></tr> 1032 * <tr><td>Locale("de", "DE")</td><td>MyResources_en.properties, parent MyResources.class</td></tr> 1033 * <tr><td>Locale("en", "US")</td><td>MyResources_en.properties, parent MyResources.class</td></tr> 1034 * <tr><td>Locale("es", "ES")</td><td>MyResources_es_ES.class, parent MyResources.class</td></tr> 1035 * </table> 1036 * 1037 * <p>The file MyResources_fr_CH.properties is never used because it is 1038 * hidden by the MyResources_fr_CH.class. Likewise, MyResources.properties 1039 * is also hidden by MyResources.class. 1040 * 1041 * @param baseName the base name of the resource bundle, a fully qualified class name 1042 * @param locale the locale for which a resource bundle is desired 1043 * @param loader the class loader from which to load the resource bundle 1044 * @return a resource bundle for the given base name and locale 1045 * @exception java.lang.NullPointerException 1046 * if <code>baseName</code>, <code>locale</code>, or <code>loader</code> is <code>null</code> 1047 * @exception MissingResourceException 1048 * if no resource bundle for the specified base name can be found 1049 * @since 1.2 1050 */ 1051 public static ResourceBundle getBundle(String baseName, Locale locale, 1052 ClassLoader loader) 1053 { 1054 if (loader == null) { 1055 throw new NullPointerException(); 1056 } 1057 return getBundleImpl(baseName, locale, loader, getDefaultControl(baseName)); 1058 } 1059 1060 /** 1061 * Returns a resource bundle using the specified base name, target 1062 * locale, class loader and control. Unlike the {@linkplain 1063 * #getBundle(String, Locale, ClassLoader) <code>getBundle</code> 1064 * factory methods with no <code>control</code> argument}, the given 1065 * <code>control</code> specifies how to locate and instantiate resource 1066 * bundles. Conceptually, the bundle loading process with the given 1067 * <code>control</code> is performed in the following steps. 1068 * 1069 * <p> 1070 * <ol> 1071 * <li>This factory method looks up the resource bundle in the cache for 1072 * the specified <code>baseName</code>, <code>targetLocale</code> and 1073 * <code>loader</code>. If the requested resource bundle instance is 1074 * found in the cache and the time-to-live periods of the instance and 1075 * all of its parent instances have not expired, the instance is returned 1076 * to the caller. Otherwise, this factory method proceeds with the 1077 * loading process below.</li> 1078 * 1079 * <li>The {@link ResourceBundle.Control#getFormats(String) 1080 * control.getFormats} method is called to get resource bundle formats 1081 * to produce bundle or resource names. The strings 1082 * <code>"java.class"</code> and <code>"java.properties"</code> 1083 * designate class-based and {@linkplain PropertyResourceBundle 1084 * property}-based resource bundles, respectively. Other strings 1085 * starting with <code>"java."</code> are reserved for future extensions 1086 * and must not be used for application-defined formats. Other strings 1087 * designate application-defined formats.</li> 1088 * 1089 * <li>The {@link ResourceBundle.Control#getCandidateLocales(String, 1090 * Locale) control.getCandidateLocales} method is called with the target 1091 * locale to get a list of <em>candidate <code>Locale</code>s</em> for 1092 * which resource bundles are searched.</li> 1093 * 1094 * <li>The {@link ResourceBundle.Control#newBundle(String, Locale, 1095 * String, ClassLoader, boolean) control.newBundle} method is called to 1096 * instantiate a <code>ResourceBundle</code> for the base bundle name, a 1097 * candidate locale, and a format. (Refer to the note on the cache 1098 * lookup below.) This step is iterated over all combinations of the 1099 * candidate locales and formats until the <code>newBundle</code> method 1100 * returns a <code>ResourceBundle</code> instance or the iteration has 1101 * used up all the combinations. For example, if the candidate locales 1102 * are <code>Locale("de", "DE")</code>, <code>Locale("de")</code> and 1103 * <code>Locale("")</code> and the formats are <code>"java.class"</code> 1104 * and <code>"java.properties"</code>, then the following is the 1105 * sequence of locale-format combinations to be used to call 1106 * <code>control.newBundle</code>. 1107 * 1108 * <table style="width: 50%; text-align: left; margin-left: 40px;" 1109 * border="0" cellpadding="2" cellspacing="2"> 1110 * <tbody><code> 1111 * <tr> 1112 * <td 1113 * style="vertical-align: top; text-align: left; font-weight: bold; width: 50%;">Locale<br> 1114 * </td> 1115 * <td 1116 * style="vertical-align: top; text-align: left; font-weight: bold; width: 50%;">format<br> 1117 * </td> 1118 * </tr> 1119 * <tr> 1120 * <td style="vertical-align: top; width: 50%;">Locale("de", "DE")<br> 1121 * </td> 1122 * <td style="vertical-align: top; width: 50%;">java.class<br> 1123 * </td> 1124 * </tr> 1125 * <tr> 1126 * <td style="vertical-align: top; width: 50%;">Locale("de", "DE")</td> 1127 * <td style="vertical-align: top; width: 50%;">java.properties<br> 1128 * </td> 1129 * </tr> 1130 * <tr> 1131 * <td style="vertical-align: top; width: 50%;">Locale("de")</td> 1132 * <td style="vertical-align: top; width: 50%;">java.class</td> 1133 * </tr> 1134 * <tr> 1135 * <td style="vertical-align: top; width: 50%;">Locale("de")</td> 1136 * <td style="vertical-align: top; width: 50%;">java.properties</td> 1137 * </tr> 1138 * <tr> 1139 * <td style="vertical-align: top; width: 50%;">Locale("")<br> 1140 * </td> 1141 * <td style="vertical-align: top; width: 50%;">java.class</td> 1142 * </tr> 1143 * <tr> 1144 * <td style="vertical-align: top; width: 50%;">Locale("")</td> 1145 * <td style="vertical-align: top; width: 50%;">java.properties</td> 1146 * </tr> 1147 * </code></tbody> 1148 * </table> 1149 * </li> 1150 * 1151 * <li>If the previous step has found no resource bundle, proceed to 1152 * Step 6. If a bundle has been found that is a base bundle (a bundle 1153 * for <code>Locale("")</code>), and the candidate locale list only contained 1154 * <code>Locale("")</code>, return the bundle to the caller. If a bundle 1155 * has been found that is a base bundle, but the candidate locale list 1156 * contained locales other than Locale(""), put the bundle on hold and 1157 * proceed to Step 6. If a bundle has been found that is not a base 1158 * bundle, proceed to Step 7.</li> 1159 * 1160 * <li>The {@link ResourceBundle.Control#getFallbackLocale(String, 1161 * Locale) control.getFallbackLocale} method is called to get a fallback 1162 * locale (alternative to the current target locale) to try further 1163 * finding a resource bundle. If the method returns a non-null locale, 1164 * it becomes the next target locale and the loading process starts over 1165 * from Step 3. Otherwise, if a base bundle was found and put on hold in 1166 * a previous Step 5, it is returned to the caller now. Otherwise, a 1167 * MissingResourceException is thrown.</li> 1168 * 1169 * <li>At this point, we have found a resource bundle that's not the 1170 * base bundle. If this bundle set its parent during its instantiation, 1171 * it is returned to the caller. Otherwise, its <a 1172 * href="./ResourceBundle.html#parent_chain">parent chain</a> is 1173 * instantiated based on the list of candidate locales from which it was 1174 * found. Finally, the bundle is returned to the caller.</li> 1175 * </ol> 1176 * 1177 * <p>During the resource bundle loading process above, this factory 1178 * method looks up the cache before calling the {@link 1179 * Control#newBundle(String, Locale, String, ClassLoader, boolean) 1180 * control.newBundle} method. If the time-to-live period of the 1181 * resource bundle found in the cache has expired, the factory method 1182 * calls the {@link ResourceBundle.Control#needsReload(String, Locale, 1183 * String, ClassLoader, ResourceBundle, long) control.needsReload} 1184 * method to determine whether the resource bundle needs to be reloaded. 1185 * If reloading is required, the factory method calls 1186 * <code>control.newBundle</code> to reload the resource bundle. If 1187 * <code>control.newBundle</code> returns <code>null</code>, the factory 1188 * method puts a dummy resource bundle in the cache as a mark of 1189 * nonexistent resource bundles in order to avoid lookup overhead for 1190 * subsequent requests. Such dummy resource bundles are under the same 1191 * expiration control as specified by <code>control</code>. 1192 * 1193 * <p>All resource bundles loaded are cached by default. Refer to 1194 * {@link Control#getTimeToLive(String,Locale) 1195 * control.getTimeToLive} for details. 1196 * 1197 * <p>The following is an example of the bundle loading process with the 1198 * default <code>ResourceBundle.Control</code> implementation. 1199 * 1200 * <p>Conditions: 1201 * <ul> 1202 * <li>Base bundle name: <code>foo.bar.Messages</code> 1203 * <li>Requested <code>Locale</code>: {@link Locale#ITALY}</li> 1204 * <li>Default <code>Locale</code>: {@link Locale#FRENCH}</li> 1205 * <li>Available resource bundles: 1206 * <code>foo/bar/Messages_fr.properties</code> and 1207 * <code>foo/bar/Messages.properties</code></li> 1208 * </ul> 1209 * 1210 * <p>First, <code>getBundle</code> tries loading a resource bundle in 1211 * the following sequence. 1212 * 1213 * <ul> 1214 * <li>class <code>foo.bar.Messages_it_IT</code> 1215 * <li>file <code>foo/bar/Messages_it_IT.properties</code> 1216 * <li>class <code>foo.bar.Messages_it</code></li> 1217 * <li>file <code>foo/bar/Messages_it.properties</code></li> 1218 * <li>class <code>foo.bar.Messages</code></li> 1219 * <li>file <code>foo/bar/Messages.properties</code></li> 1220 * </ul> 1221 * 1222 * <p>At this point, <code>getBundle</code> finds 1223 * <code>foo/bar/Messages.properties</code>, which is put on hold 1224 * because it's the base bundle. <code>getBundle</code> calls {@link 1225 * Control#getFallbackLocale(String, Locale) 1226 * control.getFallbackLocale("foo.bar.Messages", Locale.ITALY)} which 1227 * returns <code>Locale.FRENCH</code>. Next, <code>getBundle</code> 1228 * tries loading a bundle in the following sequence. 1229 * 1230 * <ul> 1231 * <li>class <code>foo.bar.Messages_fr</code></li> 1232 * <li>file <code>foo/bar/Messages_fr.properties</code></li> 1233 * <li>class <code>foo.bar.Messages</code></li> 1234 * <li>file <code>foo/bar/Messages.properties</code></li> 1235 * </ul> 1236 * 1237 * <p><code>getBundle</code> finds 1238 * <code>foo/bar/Messages_fr.properties</code> and creates a 1239 * <code>ResourceBundle</code> instance. Then, <code>getBundle</code> 1240 * sets up its parent chain from the list of the candiate locales. Only 1241 * <code>foo/bar/Messages.properties</code> is found in the list and 1242 * <code>getBundle</code> creates a <code>ResourceBundle</code> instance 1243 * that becomes the parent of the instance for 1244 * <code>foo/bar/Messages_fr.properties</code>. 1245 * 1246 * @param baseName 1247 * the base name of the resource bundle, a fully qualified 1248 * class name 1249 * @param targetLocale 1250 * the locale for which a resource bundle is desired 1251 * @param loader 1252 * the class loader from which to load the resource bundle 1253 * @param control 1254 * the control which gives information for the resource 1255 * bundle loading process 1256 * @return a resource bundle for the given base name and locale 1257 * @exception NullPointerException 1258 * if <code>baseName</code>, <code>targetLocale</code>, 1259 * <code>loader</code>, or <code>control</code> is 1260 * <code>null</code> 1261 * @exception MissingResourceException 1262 * if no resource bundle for the specified base name can be found 1263 * @exception IllegalArgumentException 1264 * if the given <code>control</code> doesn't perform properly 1265 * (e.g., <code>control.getCandidateLocales</code> returns null.) 1266 * Note that validation of <code>control</code> is performed as 1267 * needed. 1268 * @since 1.6 1269 */ 1270 public static ResourceBundle getBundle(String baseName, Locale targetLocale, 1271 ClassLoader loader, Control control) { 1272 if (loader == null || control == null) { 1273 throw new NullPointerException(); 1274 } 1275 return getBundleImpl(baseName, targetLocale, loader, control); 1276 } 1277 1278 private static Control getDefaultControl(String baseName) { 1279 if (providers != null) { 1280 for (ResourceBundleControlProvider provider : providers) { 1281 Control control = provider.getControl(baseName); 1282 if (control != null) { 1283 return control; 1284 } 1285 } 1286 } 1287 return Control.INSTANCE; 1288 } 1289 1290 private static ResourceBundle getBundleImpl(String baseName, Locale locale, 1291 ClassLoader loader, Control control) { 1292 if (locale == null || control == null) { 1293 throw new NullPointerException(); 1294 } 1295 1296 // We create a CacheKey here for use by this call. The base 1297 // name and loader will never change during the bundle loading 1298 // process. We have to make sure that the locale is set before 1299 // using it as a cache key. 1300 CacheKey cacheKey = new CacheKey(baseName, locale, loader); 1301 ResourceBundle bundle = null; 1302 1303 // Quick lookup of the cache. 1304 BundleReference bundleRef = cacheList.get(cacheKey); 1305 if (bundleRef != null) { 1306 bundle = bundleRef.get(); 1307 bundleRef = null; 1308 } 1309 1310 // If this bundle and all of its parents are valid (not expired), 1311 // then return this bundle. If any of the bundles is expired, we 1312 // don't call control.needsReload here but instead drop into the 1313 // complete loading process below. 1314 if (isValidBundle(bundle) && hasValidParentChain(bundle)) { 1315 return bundle; 1316 } 1317 1318 // No valid bundle was found in the cache, so we need to load the 1319 // resource bundle and its parents. 1320 1321 boolean isKnownControl = (control == Control.INSTANCE) || 1322 (control instanceof SingleFormatControl); 1323 List<String> formats = control.getFormats(baseName); 1324 if (!isKnownControl && !checkList(formats)) { 1325 throw new IllegalArgumentException("Invalid Control: getFormats"); 1326 } 1327 1328 ResourceBundle baseBundle = null; 1329 for (Locale targetLocale = locale; 1330 targetLocale != null; 1331 targetLocale = control.getFallbackLocale(baseName, targetLocale)) { 1332 List<Locale> candidateLocales = control.getCandidateLocales(baseName, targetLocale); 1333 if (!isKnownControl && !checkList(candidateLocales)) { 1334 throw new IllegalArgumentException("Invalid Control: getCandidateLocales"); 1335 } 1336 1337 bundle = findBundle(cacheKey, candidateLocales, formats, 0, control, baseBundle); 1338 1339 // If the loaded bundle is the base bundle and exactly for the 1340 // requested locale or the only candidate locale, then take the 1341 // bundle as the resulting one. If the loaded bundle is the base 1342 // bundle, it's put on hold until we finish processing all 1343 // fallback locales. 1344 if (isValidBundle(bundle)) { 1345 boolean isBaseBundle = Locale.ROOT.equals(bundle.locale); 1346 if (!isBaseBundle || bundle.locale.equals(locale) 1347 || (candidateLocales.size() == 1 1348 && bundle.locale.equals(candidateLocales.get(0)))) { 1349 break; 1350 } 1351 1352 // If the base bundle has been loaded, keep the reference in 1353 // baseBundle so that we can avoid any redundant loading in case 1354 // the control specify not to cache bundles. 1355 if (isBaseBundle && baseBundle == null) { 1356 baseBundle = bundle; 1357 } 1358 } 1359 } 1360 1361 if (bundle == null) { 1362 if (baseBundle == null) { 1363 throwMissingResourceException(baseName, locale, cacheKey.getCause()); 1364 } 1365 bundle = baseBundle; 1366 } 1367 1368 return bundle; 1369 } 1370 1371 /** 1372 * Checks if the given <code>List</code> is not null, not empty, 1373 * not having null in its elements. 1374 */ 1375 private static boolean checkList(List<?> a) { 1376 boolean valid = (a != null && !a.isEmpty()); 1377 if (valid) { 1378 int size = a.size(); 1379 for (int i = 0; valid && i < size; i++) { 1380 valid = (a.get(i) != null); 1381 } 1382 } 1383 return valid; 1384 } 1385 1386 private static ResourceBundle findBundle(CacheKey cacheKey, 1387 List<Locale> candidateLocales, 1388 List<String> formats, 1389 int index, 1390 Control control, 1391 ResourceBundle baseBundle) { 1392 Locale targetLocale = candidateLocales.get(index); 1393 ResourceBundle parent = null; 1394 if (index != candidateLocales.size() - 1) { 1395 parent = findBundle(cacheKey, candidateLocales, formats, index + 1, 1396 control, baseBundle); 1397 } else if (baseBundle != null && Locale.ROOT.equals(targetLocale)) { 1398 return baseBundle; 1399 } 1400 1401 // Before we do the real loading work, see whether we need to 1402 // do some housekeeping: If references to class loaders or 1403 // resource bundles have been nulled out, remove all related 1404 // information from the cache. 1405 Object ref; 1406 while ((ref = referenceQueue.poll()) != null) { 1407 cacheList.remove(((CacheKeyReference)ref).getCacheKey()); 1408 } 1409 1410 // flag indicating the resource bundle has expired in the cache 1411 boolean expiredBundle = false; 1412 1413 // First, look up the cache to see if it's in the cache, without 1414 // attempting to load bundle. 1415 cacheKey.setLocale(targetLocale); 1416 ResourceBundle bundle = findBundleInCache(cacheKey, control); 1417 if (isValidBundle(bundle)) { 1418 expiredBundle = bundle.expired; 1419 if (!expiredBundle) { 1420 // If its parent is the one asked for by the candidate 1421 // locales (the runtime lookup path), we can take the cached 1422 // one. (If it's not identical, then we'd have to check the 1423 // parent's parents to be consistent with what's been 1424 // requested.) 1425 if (bundle.parent == parent) { 1426 return bundle; 1427 } 1428 // Otherwise, remove the cached one since we can't keep 1429 // the same bundles having different parents. 1430 BundleReference bundleRef = cacheList.get(cacheKey); 1431 if (bundleRef != null && bundleRef.get() == bundle) { 1432 cacheList.remove(cacheKey, bundleRef); 1433 } 1434 } 1435 } 1436 1437 if (bundle != NONEXISTENT_BUNDLE) { 1438 CacheKey constKey = (CacheKey) cacheKey.clone(); 1439 1440 try { 1441 bundle = loadBundle(cacheKey, formats, control, expiredBundle); 1442 if (bundle != null) { 1443 if (bundle.parent == null) { 1444 bundle.setParent(parent); 1445 } 1446 bundle.locale = targetLocale; 1447 bundle = putBundleInCache(cacheKey, bundle, control); 1448 return bundle; 1449 } 1450 1451 // Put NONEXISTENT_BUNDLE in the cache as a mark that there's no bundle 1452 // instance for the locale. 1453 putBundleInCache(cacheKey, NONEXISTENT_BUNDLE, control); 1454 } finally { 1455 if (constKey.getCause() instanceof InterruptedException) { 1456 Thread.currentThread().interrupt(); 1457 } 1458 } 1459 } 1460 return parent; 1461 } 1462 1463 private static ResourceBundle loadBundle(CacheKey cacheKey, 1464 List<String> formats, 1465 Control control, 1466 boolean reload) { 1467 1468 // Here we actually load the bundle in the order of formats 1469 // specified by the getFormats() value. 1470 Locale targetLocale = cacheKey.getLocale(); 1471 1472 ResourceBundle bundle = null; 1473 int size = formats.size(); 1474 for (int i = 0; i < size; i++) { 1475 String format = formats.get(i); 1476 try { 1477 bundle = control.newBundle(cacheKey.getName(), targetLocale, format, 1478 cacheKey.getLoader(), reload); 1479 } catch (LinkageError error) { 1480 // We need to handle the LinkageError case due to 1481 // inconsistent case-sensitivity in ClassLoader. 1482 // See 6572242 for details. 1483 cacheKey.setCause(error); 1484 } catch (Exception cause) { 1485 cacheKey.setCause(cause); 1486 } 1487 if (bundle != null) { 1488 // Set the format in the cache key so that it can be 1489 // used when calling needsReload later. 1490 cacheKey.setFormat(format); 1491 bundle.name = cacheKey.getName(); 1492 bundle.locale = targetLocale; 1493 // Bundle provider might reuse instances. So we should make 1494 // sure to clear the expired flag here. 1495 bundle.expired = false; 1496 break; 1497 } 1498 } 1499 1500 return bundle; 1501 } 1502 1503 private static boolean isValidBundle(ResourceBundle bundle) { 1504 return bundle != null && bundle != NONEXISTENT_BUNDLE; 1505 } 1506 1507 /** 1508 * Determines whether any of resource bundles in the parent chain, 1509 * including the leaf, have expired. 1510 */ 1511 private static boolean hasValidParentChain(ResourceBundle bundle) { 1512 long now = System.currentTimeMillis(); 1513 while (bundle != null) { 1514 if (bundle.expired) { 1515 return false; 1516 } 1517 CacheKey key = bundle.cacheKey; 1518 if (key != null) { 1519 long expirationTime = key.expirationTime; 1520 if (expirationTime >= 0 && expirationTime <= now) { 1521 return false; 1522 } 1523 } 1524 bundle = bundle.parent; 1525 } 1526 return true; 1527 } 1528 1529 /** 1530 * Throw a MissingResourceException with proper message 1531 */ 1532 private static void throwMissingResourceException(String baseName, 1533 Locale locale, 1534 Throwable cause) { 1535 // If the cause is a MissingResourceException, avoid creating 1536 // a long chain. (6355009) 1537 if (cause instanceof MissingResourceException) { 1538 cause = null; 1539 } 1540 throw new MissingResourceException("Can't find bundle for base name " 1541 + baseName + ", locale " + locale, 1542 baseName + "_" + locale, // className 1543 "", // key 1544 cause); 1545 } 1546 1547 /** 1548 * Finds a bundle in the cache. Any expired bundles are marked as 1549 * `expired' and removed from the cache upon return. 1550 * 1551 * @param cacheKey the key to look up the cache 1552 * @param control the Control to be used for the expiration control 1553 * @return the cached bundle, or null if the bundle is not found in the 1554 * cache or its parent has expired. <code>bundle.expire</code> is true 1555 * upon return if the bundle in the cache has expired. 1556 */ 1557 private static ResourceBundle findBundleInCache(CacheKey cacheKey, 1558 Control control) { 1559 BundleReference bundleRef = cacheList.get(cacheKey); 1560 if (bundleRef == null) { 1561 return null; 1562 } 1563 ResourceBundle bundle = bundleRef.get(); 1564 if (bundle == null) { 1565 return null; 1566 } 1567 ResourceBundle p = bundle.parent; 1568 assert p != NONEXISTENT_BUNDLE; 1569 // If the parent has expired, then this one must also expire. We 1570 // check only the immediate parent because the actual loading is 1571 // done from the root (base) to leaf (child) and the purpose of 1572 // checking is to propagate expiration towards the leaf. For 1573 // example, if the requested locale is ja_JP_JP and there are 1574 // bundles for all of the candidates in the cache, we have a list, 1575 // 1576 // base <- ja <- ja_JP <- ja_JP_JP 1577 // 1578 // If ja has expired, then it will reload ja and the list becomes a 1579 // tree. 1580 // 1581 // base <- ja (new) 1582 // " <- ja (expired) <- ja_JP <- ja_JP_JP 1583 // 1584 // When looking up ja_JP in the cache, it finds ja_JP in the cache 1585 // which references to the expired ja. Then, ja_JP is marked as 1586 // expired and removed from the cache. This will be propagated to 1587 // ja_JP_JP. 1588 // 1589 // Now, it's possible, for example, that while loading new ja_JP, 1590 // someone else has started loading the same bundle and finds the 1591 // base bundle has expired. Then, what we get from the first 1592 // getBundle call includes the expired base bundle. However, if 1593 // someone else didn't start its loading, we wouldn't know if the 1594 // base bundle has expired at the end of the loading process. The 1595 // expiration control doesn't guarantee that the returned bundle and 1596 // its parents haven't expired. 1597 // 1598 // We could check the entire parent chain to see if there's any in 1599 // the chain that has expired. But this process may never end. An 1600 // extreme case would be that getTimeToLive returns 0 and 1601 // needsReload always returns true. 1602 if (p != null && p.expired) { 1603 assert bundle != NONEXISTENT_BUNDLE; 1604 bundle.expired = true; 1605 bundle.cacheKey = null; 1606 cacheList.remove(cacheKey, bundleRef); 1607 bundle = null; 1608 } else { 1609 CacheKey key = bundleRef.getCacheKey(); 1610 long expirationTime = key.expirationTime; 1611 if (!bundle.expired && expirationTime >= 0 && 1612 expirationTime <= System.currentTimeMillis()) { 1613 // its TTL period has expired. 1614 if (bundle != NONEXISTENT_BUNDLE) { 1615 // Synchronize here to call needsReload to avoid 1616 // redundant concurrent calls for the same bundle. 1617 synchronized (bundle) { 1618 expirationTime = key.expirationTime; 1619 if (!bundle.expired && expirationTime >= 0 && 1620 expirationTime <= System.currentTimeMillis()) { 1621 try { 1622 bundle.expired = control.needsReload(key.getName(), 1623 key.getLocale(), 1624 key.getFormat(), 1625 key.getLoader(), 1626 bundle, 1627 key.loadTime); 1628 } catch (Exception e) { 1629 cacheKey.setCause(e); 1630 } 1631 if (bundle.expired) { 1632 // If the bundle needs to be reloaded, then 1633 // remove the bundle from the cache, but 1634 // return the bundle with the expired flag 1635 // on. 1636 bundle.cacheKey = null; 1637 cacheList.remove(cacheKey, bundleRef); 1638 } else { 1639 // Update the expiration control info. and reuse 1640 // the same bundle instance 1641 setExpirationTime(key, control); 1642 } 1643 } 1644 } 1645 } else { 1646 // We just remove NONEXISTENT_BUNDLE from the cache. 1647 cacheList.remove(cacheKey, bundleRef); 1648 bundle = null; 1649 } 1650 } 1651 } 1652 return bundle; 1653 } 1654 1655 /** 1656 * Put a new bundle in the cache. 1657 * 1658 * @param cacheKey the key for the resource bundle 1659 * @param bundle the resource bundle to be put in the cache 1660 * @return the ResourceBundle for the cacheKey; if someone has put 1661 * the bundle before this call, the one found in the cache is 1662 * returned. 1663 */ 1664 private static ResourceBundle putBundleInCache(CacheKey cacheKey, 1665 ResourceBundle bundle, 1666 Control control) { 1667 setExpirationTime(cacheKey, control); 1668 if (cacheKey.expirationTime != Control.TTL_DONT_CACHE) { 1669 CacheKey key = (CacheKey) cacheKey.clone(); 1670 BundleReference bundleRef = new BundleReference(bundle, referenceQueue, key); 1671 bundle.cacheKey = key; 1672 1673 // Put the bundle in the cache if it's not been in the cache. 1674 BundleReference result = cacheList.putIfAbsent(key, bundleRef); 1675 1676 // If someone else has put the same bundle in the cache before 1677 // us and it has not expired, we should use the one in the cache. 1678 if (result != null) { 1679 ResourceBundle rb = result.get(); 1680 if (rb != null && !rb.expired) { 1681 // Clear the back link to the cache key 1682 bundle.cacheKey = null; 1683 bundle = rb; 1684 // Clear the reference in the BundleReference so that 1685 // it won't be enqueued. 1686 bundleRef.clear(); 1687 } else { 1688 // Replace the invalid (garbage collected or expired) 1689 // instance with the valid one. 1690 cacheList.put(key, bundleRef); 1691 } 1692 } 1693 } 1694 return bundle; 1695 } 1696 1697 private static void setExpirationTime(CacheKey cacheKey, Control control) { 1698 long ttl = control.getTimeToLive(cacheKey.getName(), 1699 cacheKey.getLocale()); 1700 if (ttl >= 0) { 1701 // If any expiration time is specified, set the time to be 1702 // expired in the cache. 1703 long now = System.currentTimeMillis(); 1704 cacheKey.loadTime = now; 1705 cacheKey.expirationTime = now + ttl; 1706 } else if (ttl >= Control.TTL_NO_EXPIRATION_CONTROL) { 1707 cacheKey.expirationTime = ttl; 1708 } else { 1709 throw new IllegalArgumentException("Invalid Control: TTL=" + ttl); 1710 } 1711 } 1712 1713 /** 1714 * Removes all resource bundles from the cache that have been loaded 1715 * using the caller's class loader. 1716 * 1717 * @since 1.6 1718 * @see ResourceBundle.Control#getTimeToLive(String,Locale) 1719 */ 1720 @CallerSensitive 1721 public static final void clearCache() { 1722 clearCache(getLoader(Reflection.getCallerClass())); 1723 } 1724 1725 /** 1726 * Removes all resource bundles from the cache that have been loaded 1727 * using the given class loader. 1728 * 1729 * @param loader the class loader 1730 * @exception NullPointerException if <code>loader</code> is null 1731 * @since 1.6 1732 * @see ResourceBundle.Control#getTimeToLive(String,Locale) 1733 */ 1734 public static final void clearCache(ClassLoader loader) { 1735 if (loader == null) { 1736 throw new NullPointerException(); 1737 } 1738 Set<CacheKey> set = cacheList.keySet(); 1739 for (CacheKey key : set) { 1740 if (key.getLoader() == loader) { 1741 set.remove(key); 1742 } 1743 } 1744 } 1745 1746 /** 1747 * Gets an object for the given key from this resource bundle. 1748 * Returns null if this resource bundle does not contain an 1749 * object for the given key. 1750 * 1751 * @param key the key for the desired object 1752 * @exception NullPointerException if <code>key</code> is <code>null</code> 1753 * @return the object for the given key, or null 1754 */ 1755 protected abstract Object handleGetObject(String key); 1756 1757 /** 1758 * Returns an enumeration of the keys. 1759 * 1760 * @return an <code>Enumeration</code> of the keys contained in 1761 * this <code>ResourceBundle</code> and its parent bundles. 1762 */ 1763 public abstract Enumeration<String> getKeys(); 1764 1765 /** 1766 * Determines whether the given <code>key</code> is contained in 1767 * this <code>ResourceBundle</code> or its parent bundles. 1768 * 1769 * @param key 1770 * the resource <code>key</code> 1771 * @return <code>true</code> if the given <code>key</code> is 1772 * contained in this <code>ResourceBundle</code> or its 1773 * parent bundles; <code>false</code> otherwise. 1774 * @exception NullPointerException 1775 * if <code>key</code> is <code>null</code> 1776 * @since 1.6 1777 */ 1778 public boolean containsKey(String key) { 1779 if (key == null) { 1780 throw new NullPointerException(); 1781 } 1782 for (ResourceBundle rb = this; rb != null; rb = rb.parent) { 1783 if (rb.handleKeySet().contains(key)) { 1784 return true; 1785 } 1786 } 1787 return false; 1788 } 1789 1790 /** 1791 * Returns a <code>Set</code> of all keys contained in this 1792 * <code>ResourceBundle</code> and its parent bundles. 1793 * 1794 * @return a <code>Set</code> of all keys contained in this 1795 * <code>ResourceBundle</code> and its parent bundles. 1796 * @since 1.6 1797 */ 1798 public Set<String> keySet() { 1799 Set<String> keys = new HashSet<>(); 1800 for (ResourceBundle rb = this; rb != null; rb = rb.parent) { 1801 keys.addAll(rb.handleKeySet()); 1802 } 1803 return keys; 1804 } 1805 1806 /** 1807 * Returns a <code>Set</code> of the keys contained <em>only</em> 1808 * in this <code>ResourceBundle</code>. 1809 * 1810 * <p>The default implementation returns a <code>Set</code> of the 1811 * keys returned by the {@link #getKeys() getKeys} method except 1812 * for the ones for which the {@link #handleGetObject(String) 1813 * handleGetObject} method returns <code>null</code>. Once the 1814 * <code>Set</code> has been created, the value is kept in this 1815 * <code>ResourceBundle</code> in order to avoid producing the 1816 * same <code>Set</code> in subsequent calls. Subclasses can 1817 * override this method for faster handling. 1818 * 1819 * @return a <code>Set</code> of the keys contained only in this 1820 * <code>ResourceBundle</code> 1821 * @since 1.6 1822 */ 1823 protected Set<String> handleKeySet() { 1824 if (keySet == null) { 1825 synchronized (this) { 1826 if (keySet == null) { 1827 Set<String> keys = new HashSet<>(); 1828 Enumeration<String> enumKeys = getKeys(); 1829 while (enumKeys.hasMoreElements()) { 1830 String key = enumKeys.nextElement(); 1831 if (handleGetObject(key) != null) { 1832 keys.add(key); 1833 } 1834 } 1835 keySet = keys; 1836 } 1837 } 1838 } 1839 return keySet; 1840 } 1841 1842 1843 1844 /** 1845 * <code>ResourceBundle.Control</code> defines a set of callback methods 1846 * that are invoked by the {@link ResourceBundle#getBundle(String, 1847 * Locale, ClassLoader, Control) ResourceBundle.getBundle} factory 1848 * methods during the bundle loading process. In other words, a 1849 * <code>ResourceBundle.Control</code> collaborates with the factory 1850 * methods for loading resource bundles. The default implementation of 1851 * the callback methods provides the information necessary for the 1852 * factory methods to perform the <a 1853 * href="./ResourceBundle.html#default_behavior">default behavior</a>. 1854 * 1855 * <p>In addition to the callback methods, the {@link 1856 * #toBundleName(String, Locale) toBundleName} and {@link 1857 * #toResourceName(String, String) toResourceName} methods are defined 1858 * primarily for convenience in implementing the callback 1859 * methods. However, the <code>toBundleName</code> method could be 1860 * overridden to provide different conventions in the organization and 1861 * packaging of localized resources. The <code>toResourceName</code> 1862 * method is <code>final</code> to avoid use of wrong resource and class 1863 * name separators. 1864 * 1865 * <p>Two factory methods, {@link #getControl(List)} and {@link 1866 * #getNoFallbackControl(List)}, provide 1867 * <code>ResourceBundle.Control</code> instances that implement common 1868 * variations of the default bundle loading process. 1869 * 1870 * <p>The formats returned by the {@link Control#getFormats(String) 1871 * getFormats} method and candidate locales returned by the {@link 1872 * ResourceBundle.Control#getCandidateLocales(String, Locale) 1873 * getCandidateLocales} method must be consistent in all 1874 * <code>ResourceBundle.getBundle</code> invocations for the same base 1875 * bundle. Otherwise, the <code>ResourceBundle.getBundle</code> methods 1876 * may return unintended bundles. For example, if only 1877 * <code>"java.class"</code> is returned by the <code>getFormats</code> 1878 * method for the first call to <code>ResourceBundle.getBundle</code> 1879 * and only <code>"java.properties"</code> for the second call, then the 1880 * second call will return the class-based one that has been cached 1881 * during the first call. 1882 * 1883 * <p>A <code>ResourceBundle.Control</code> instance must be thread-safe 1884 * if it's simultaneously used by multiple threads. 1885 * <code>ResourceBundle.getBundle</code> does not synchronize to call 1886 * the <code>ResourceBundle.Control</code> methods. The default 1887 * implementations of the methods are thread-safe. 1888 * 1889 * <p>Applications can specify <code>ResourceBundle.Control</code> 1890 * instances returned by the <code>getControl</code> factory methods or 1891 * created from a subclass of <code>ResourceBundle.Control</code> to 1892 * customize the bundle loading process. The following are examples of 1893 * changing the default bundle loading process. 1894 * 1895 * <p><b>Example 1</b> 1896 * 1897 * <p>The following code lets <code>ResourceBundle.getBundle</code> look 1898 * up only properties-based resources. 1899 * 1900 * <pre> 1901 * import java.util.*; 1902 * import static java.util.ResourceBundle.Control.*; 1903 * ... 1904 * ResourceBundle bundle = 1905 * ResourceBundle.getBundle("MyResources", new Locale("fr", "CH"), 1906 * ResourceBundle.Control.getControl(FORMAT_PROPERTIES)); 1907 * </pre> 1908 * 1909 * Given the resource bundles in the <a 1910 * href="./ResourceBundle.html#default_behavior_example">example</a> in 1911 * the <code>ResourceBundle.getBundle</code> description, this 1912 * <code>ResourceBundle.getBundle</code> call loads 1913 * <code>MyResources_fr_CH.properties</code> whose parent is 1914 * <code>MyResources_fr.properties</code> whose parent is 1915 * <code>MyResources.properties</code>. (<code>MyResources_fr_CH.properties</code> 1916 * is not hidden, but <code>MyResources_fr_CH.class</code> is.) 1917 * 1918 * <p><b>Example 2</b> 1919 * 1920 * <p>The following is an example of loading XML-based bundles 1921 * using {@link Properties#loadFromXML(java.io.InputStream) 1922 * Properties.loadFromXML}. 1923 * 1924 * <pre> 1925 * ResourceBundle rb = ResourceBundle.getBundle("Messages", 1926 * new ResourceBundle.Control() { 1927 * public List<String> getFormats(String baseName) { 1928 * if (baseName == null) 1929 * throw new NullPointerException(); 1930 * return Arrays.asList("xml"); 1931 * } 1932 * public ResourceBundle newBundle(String baseName, 1933 * Locale locale, 1934 * String format, 1935 * ClassLoader loader, 1936 * boolean reload) 1937 * throws IllegalAccessException, 1938 * InstantiationException, 1939 * IOException { 1940 * if (baseName == null || locale == null 1941 * || format == null || loader == null) 1942 * throw new NullPointerException(); 1943 * ResourceBundle bundle = null; 1944 * if (format.equals("xml")) { 1945 * String bundleName = toBundleName(baseName, locale); 1946 * String resourceName = toResourceName(bundleName, format); 1947 * InputStream stream = null; 1948 * if (reload) { 1949 * URL url = loader.getResource(resourceName); 1950 * if (url != null) { 1951 * URLConnection connection = url.openConnection(); 1952 * if (connection != null) { 1953 * // Disable caches to get fresh data for 1954 * // reloading. 1955 * connection.setUseCaches(false); 1956 * stream = connection.getInputStream(); 1957 * } 1958 * } 1959 * } else { 1960 * stream = loader.getResourceAsStream(resourceName); 1961 * } 1962 * if (stream != null) { 1963 * BufferedInputStream bis = new BufferedInputStream(stream); 1964 * bundle = new XMLResourceBundle(bis); 1965 * bis.close(); 1966 * } 1967 * } 1968 * return bundle; 1969 * } 1970 * }); 1971 * 1972 * ... 1973 * 1974 * private static class XMLResourceBundle extends ResourceBundle { 1975 * private Properties props; 1976 * XMLResourceBundle(InputStream stream) throws IOException { 1977 * props = new Properties(); 1978 * props.loadFromXML(stream); 1979 * } 1980 * protected Object handleGetObject(String key) { 1981 * return props.getProperty(key); 1982 * } 1983 * public Enumeration<String> getKeys() { 1984 * ... 1985 * } 1986 * } 1987 * </pre> 1988 * 1989 * @since 1.6 1990 */ 1991 public static class Control { 1992 /** 1993 * The default format <code>List</code>, which contains the strings 1994 * <code>"java.class"</code> and <code>"java.properties"</code>, in 1995 * this order. This <code>List</code> is {@linkplain 1996 * Collections#unmodifiableList(List) unmodifiable}. 1997 * 1998 * @see #getFormats(String) 1999 */ 2000 public static final List<String> FORMAT_DEFAULT 2001 = Collections.unmodifiableList(Arrays.asList("java.class", 2002 "java.properties")); 2003 2004 /** 2005 * The class-only format <code>List</code> containing 2006 * <code>"java.class"</code>. This <code>List</code> is {@linkplain 2007 * Collections#unmodifiableList(List) unmodifiable}. 2008 * 2009 * @see #getFormats(String) 2010 */ 2011 public static final List<String> FORMAT_CLASS 2012 = Collections.unmodifiableList(Arrays.asList("java.class")); 2013 2014 /** 2015 * The properties-only format <code>List</code> containing 2016 * <code>"java.properties"</code>. This <code>List</code> is 2017 * {@linkplain Collections#unmodifiableList(List) unmodifiable}. 2018 * 2019 * @see #getFormats(String) 2020 */ 2021 public static final List<String> FORMAT_PROPERTIES 2022 = Collections.unmodifiableList(Arrays.asList("java.properties")); 2023 2024 /** 2025 * The time-to-live constant for not caching loaded resource bundle 2026 * instances. 2027 * 2028 * @see #getTimeToLive(String, Locale) 2029 */ 2030 public static final long TTL_DONT_CACHE = -1; 2031 2032 /** 2033 * The time-to-live constant for disabling the expiration control 2034 * for loaded resource bundle instances in the cache. 2035 * 2036 * @see #getTimeToLive(String, Locale) 2037 */ 2038 public static final long TTL_NO_EXPIRATION_CONTROL = -2; 2039 2040 private static final Control INSTANCE = new Control(); 2041 2042 /** 2043 * Sole constructor. (For invocation by subclass constructors, 2044 * typically implicit.) 2045 */ 2046 protected Control() { 2047 } 2048 2049 /** 2050 * Returns a <code>ResourceBundle.Control</code> in which the {@link 2051 * #getFormats(String) getFormats} method returns the specified 2052 * <code>formats</code>. The <code>formats</code> must be equal to 2053 * one of {@link Control#FORMAT_PROPERTIES}, {@link 2054 * Control#FORMAT_CLASS} or {@link 2055 * Control#FORMAT_DEFAULT}. <code>ResourceBundle.Control</code> 2056 * instances returned by this method are singletons and thread-safe. 2057 * 2058 * <p>Specifying {@link Control#FORMAT_DEFAULT} is equivalent to 2059 * instantiating the <code>ResourceBundle.Control</code> class, 2060 * except that this method returns a singleton. 2061 * 2062 * @param formats 2063 * the formats to be returned by the 2064 * <code>ResourceBundle.Control.getFormats</code> method 2065 * @return a <code>ResourceBundle.Control</code> supporting the 2066 * specified <code>formats</code> 2067 * @exception NullPointerException 2068 * if <code>formats</code> is <code>null</code> 2069 * @exception IllegalArgumentException 2070 * if <code>formats</code> is unknown 2071 */ 2072 public static final Control getControl(List<String> formats) { 2073 if (formats.equals(Control.FORMAT_PROPERTIES)) { 2074 return SingleFormatControl.PROPERTIES_ONLY; 2075 } 2076 if (formats.equals(Control.FORMAT_CLASS)) { 2077 return SingleFormatControl.CLASS_ONLY; 2078 } 2079 if (formats.equals(Control.FORMAT_DEFAULT)) { 2080 return Control.INSTANCE; 2081 } 2082 throw new IllegalArgumentException(); 2083 } 2084 2085 /** 2086 * Returns a <code>ResourceBundle.Control</code> in which the {@link 2087 * #getFormats(String) getFormats} method returns the specified 2088 * <code>formats</code> and the {@link 2089 * Control#getFallbackLocale(String, Locale) getFallbackLocale} 2090 * method returns <code>null</code>. The <code>formats</code> must 2091 * be equal to one of {@link Control#FORMAT_PROPERTIES}, {@link 2092 * Control#FORMAT_CLASS} or {@link Control#FORMAT_DEFAULT}. 2093 * <code>ResourceBundle.Control</code> instances returned by this 2094 * method are singletons and thread-safe. 2095 * 2096 * @param formats 2097 * the formats to be returned by the 2098 * <code>ResourceBundle.Control.getFormats</code> method 2099 * @return a <code>ResourceBundle.Control</code> supporting the 2100 * specified <code>formats</code> with no fallback 2101 * <code>Locale</code> support 2102 * @exception NullPointerException 2103 * if <code>formats</code> is <code>null</code> 2104 * @exception IllegalArgumentException 2105 * if <code>formats</code> is unknown 2106 */ 2107 public static final Control getNoFallbackControl(List<String> formats) { 2108 if (formats.equals(Control.FORMAT_DEFAULT)) { 2109 return NoFallbackControl.NO_FALLBACK; 2110 } 2111 if (formats.equals(Control.FORMAT_PROPERTIES)) { 2112 return NoFallbackControl.PROPERTIES_ONLY_NO_FALLBACK; 2113 } 2114 if (formats.equals(Control.FORMAT_CLASS)) { 2115 return NoFallbackControl.CLASS_ONLY_NO_FALLBACK; 2116 } 2117 throw new IllegalArgumentException(); 2118 } 2119 2120 /** 2121 * Returns a <code>List</code> of <code>String</code>s containing 2122 * formats to be used to load resource bundles for the given 2123 * <code>baseName</code>. The <code>ResourceBundle.getBundle</code> 2124 * factory method tries to load resource bundles with formats in the 2125 * order specified by the list. The list returned by this method 2126 * must have at least one <code>String</code>. The predefined 2127 * formats are <code>"java.class"</code> for class-based resource 2128 * bundles and <code>"java.properties"</code> for {@linkplain 2129 * PropertyResourceBundle properties-based} ones. Strings starting 2130 * with <code>"java."</code> are reserved for future extensions and 2131 * must not be used by application-defined formats. 2132 * 2133 * <p>It is not a requirement to return an immutable (unmodifiable) 2134 * <code>List</code>. However, the returned <code>List</code> must 2135 * not be mutated after it has been returned by 2136 * <code>getFormats</code>. 2137 * 2138 * <p>The default implementation returns {@link #FORMAT_DEFAULT} so 2139 * that the <code>ResourceBundle.getBundle</code> factory method 2140 * looks up first class-based resource bundles, then 2141 * properties-based ones. 2142 * 2143 * @param baseName 2144 * the base name of the resource bundle, a fully qualified class 2145 * name 2146 * @return a <code>List</code> of <code>String</code>s containing 2147 * formats for loading resource bundles. 2148 * @exception NullPointerException 2149 * if <code>baseName</code> is null 2150 * @see #FORMAT_DEFAULT 2151 * @see #FORMAT_CLASS 2152 * @see #FORMAT_PROPERTIES 2153 */ 2154 public List<String> getFormats(String baseName) { 2155 if (baseName == null) { 2156 throw new NullPointerException(); 2157 } 2158 return FORMAT_DEFAULT; 2159 } 2160 2161 /** 2162 * Returns a <code>List</code> of <code>Locale</code>s as candidate 2163 * locales for <code>baseName</code> and <code>locale</code>. This 2164 * method is called by the <code>ResourceBundle.getBundle</code> 2165 * factory method each time the factory method tries finding a 2166 * resource bundle for a target <code>Locale</code>. 2167 * 2168 * <p>The sequence of the candidate locales also corresponds to the 2169 * runtime resource lookup path (also known as the <I>parent 2170 * chain</I>), if the corresponding resource bundles for the 2171 * candidate locales exist and their parents are not defined by 2172 * loaded resource bundles themselves. The last element of the list 2173 * must be a {@linkplain Locale#ROOT root locale} if it is desired to 2174 * have the base bundle as the terminal of the parent chain. 2175 * 2176 * <p>If the given locale is equal to <code>Locale.ROOT</code> (the 2177 * root locale), a <code>List</code> containing only the root 2178 * <code>Locale</code> must be returned. In this case, the 2179 * <code>ResourceBundle.getBundle</code> factory method loads only 2180 * the base bundle as the resulting resource bundle. 2181 * 2182 * <p>It is not a requirement to return an immutable (unmodifiable) 2183 * <code>List</code>. However, the returned <code>List</code> must not 2184 * be mutated after it has been returned by 2185 * <code>getCandidateLocales</code>. 2186 * 2187 * <p>The default implementation returns a <code>List</code> containing 2188 * <code>Locale</code>s using the rules described below. In the 2189 * description below, <em>L</em>, <em>S</em>, <em>C</em> and <em>V</em> 2190 * respectively represent non-empty language, script, country, and 2191 * variant. For example, [<em>L</em>, <em>C</em>] represents a 2192 * <code>Locale</code> that has non-empty values only for language and 2193 * country. The form <em>L</em>("xx") represents the (non-empty) 2194 * language value is "xx". For all cases, <code>Locale</code>s whose 2195 * final component values are empty strings are omitted. 2196 * 2197 * <ol><li>For an input <code>Locale</code> with an empty script value, 2198 * append candidate <code>Locale</code>s by omitting the final component 2199 * one by one as below: 2200 * 2201 * <ul> 2202 * <li> [<em>L</em>, <em>C</em>, <em>V</em>] 2203 * <li> [<em>L</em>, <em>C</em>] 2204 * <li> [<em>L</em>] 2205 * <li> <code>Locale.ROOT</code> 2206 * </ul> 2207 * 2208 * <li>For an input <code>Locale</code> with a non-empty script value, 2209 * append candidate <code>Locale</code>s by omitting the final component 2210 * up to language, then append candidates generated from the 2211 * <code>Locale</code> with country and variant restored: 2212 * 2213 * <ul> 2214 * <li> [<em>L</em>, <em>S</em>, <em>C</em>, <em>V</em>] 2215 * <li> [<em>L</em>, <em>S</em>, <em>C</em>] 2216 * <li> [<em>L</em>, <em>S</em>] 2217 * <li> [<em>L</em>, <em>C</em>, <em>V</em>] 2218 * <li> [<em>L</em>, <em>C</em>] 2219 * <li> [<em>L</em>] 2220 * <li> <code>Locale.ROOT</code> 2221 * </ul> 2222 * 2223 * <li>For an input <code>Locale</code> with a variant value consisting 2224 * of multiple subtags separated by underscore, generate candidate 2225 * <code>Locale</code>s by omitting the variant subtags one by one, then 2226 * insert them after every occurence of <code> Locale</code>s with the 2227 * full variant value in the original list. For example, if the 2228 * the variant consists of two subtags <em>V1</em> and <em>V2</em>: 2229 * 2230 * <ul> 2231 * <li> [<em>L</em>, <em>S</em>, <em>C</em>, <em>V1</em>, <em>V2</em>] 2232 * <li> [<em>L</em>, <em>S</em>, <em>C</em>, <em>V1</em>] 2233 * <li> [<em>L</em>, <em>S</em>, <em>C</em>] 2234 * <li> [<em>L</em>, <em>S</em>] 2235 * <li> [<em>L</em>, <em>C</em>, <em>V1</em>, <em>V2</em>] 2236 * <li> [<em>L</em>, <em>C</em>, <em>V1</em>] 2237 * <li> [<em>L</em>, <em>C</em>] 2238 * <li> [<em>L</em>] 2239 * <li> <code>Locale.ROOT</code> 2240 * </ul> 2241 * 2242 * <li>Special cases for Chinese. When an input <code>Locale</code> has the 2243 * language "zh" (Chinese) and an empty script value, either "Hans" (Simplified) or 2244 * "Hant" (Traditional) might be supplied, depending on the country. 2245 * When the country is "CN" (China) or "SG" (Singapore), "Hans" is supplied. 2246 * When the country is "HK" (Hong Kong SAR China), "MO" (Macau SAR China), 2247 * or "TW" (Taiwan), "Hant" is supplied. For all other countries or when the country 2248 * is empty, no script is supplied. For example, for <code>Locale("zh", "CN") 2249 * </code>, the candidate list will be: 2250 * <ul> 2251 * <li> [<em>L</em>("zh"), <em>S</em>("Hans"), <em>C</em>("CN")] 2252 * <li> [<em>L</em>("zh"), <em>S</em>("Hans")] 2253 * <li> [<em>L</em>("zh"), <em>C</em>("CN")] 2254 * <li> [<em>L</em>("zh")] 2255 * <li> <code>Locale.ROOT</code> 2256 * </ul> 2257 * 2258 * For <code>Locale("zh", "TW")</code>, the candidate list will be: 2259 * <ul> 2260 * <li> [<em>L</em>("zh"), <em>S</em>("Hant"), <em>C</em>("TW")] 2261 * <li> [<em>L</em>("zh"), <em>S</em>("Hant")] 2262 * <li> [<em>L</em>("zh"), <em>C</em>("TW")] 2263 * <li> [<em>L</em>("zh")] 2264 * <li> <code>Locale.ROOT</code> 2265 * </ul> 2266 * 2267 * <li>Special cases for Norwegian. Both <code>Locale("no", "NO", 2268 * "NY")</code> and <code>Locale("nn", "NO")</code> represent Norwegian 2269 * Nynorsk. When a locale's language is "nn", the standard candidate 2270 * list is generated up to [<em>L</em>("nn")], and then the following 2271 * candidates are added: 2272 * 2273 * <ul><li> [<em>L</em>("no"), <em>C</em>("NO"), <em>V</em>("NY")] 2274 * <li> [<em>L</em>("no"), <em>C</em>("NO")] 2275 * <li> [<em>L</em>("no")] 2276 * <li> <code>Locale.ROOT</code> 2277 * </ul> 2278 * 2279 * If the locale is exactly <code>Locale("no", "NO", "NY")</code>, it is first 2280 * converted to <code>Locale("nn", "NO")</code> and then the above procedure is 2281 * followed. 2282 * 2283 * <p>Also, Java treats the language "no" as a synonym of Norwegian 2284 * Bokmål "nb". Except for the single case <code>Locale("no", 2285 * "NO", "NY")</code> (handled above), when an input <code>Locale</code> 2286 * has language "no" or "nb", candidate <code>Locale</code>s with 2287 * language code "no" and "nb" are interleaved, first using the 2288 * requested language, then using its synonym. For example, 2289 * <code>Locale("nb", "NO", "POSIX")</code> generates the following 2290 * candidate list: 2291 * 2292 * <ul> 2293 * <li> [<em>L</em>("nb"), <em>C</em>("NO"), <em>V</em>("POSIX")] 2294 * <li> [<em>L</em>("no"), <em>C</em>("NO"), <em>V</em>("POSIX")] 2295 * <li> [<em>L</em>("nb"), <em>C</em>("NO")] 2296 * <li> [<em>L</em>("no"), <em>C</em>("NO")] 2297 * <li> [<em>L</em>("nb")] 2298 * <li> [<em>L</em>("no")] 2299 * <li> <code>Locale.ROOT</code> 2300 * </ul> 2301 * 2302 * <code>Locale("no", "NO", "POSIX")</code> would generate the same list 2303 * except that locales with "no" would appear before the corresponding 2304 * locales with "nb".</li> 2305 * 2306 * </li> 2307 * </ol> 2308 * 2309 * <p>The default implementation uses an {@link ArrayList} that 2310 * overriding implementations may modify before returning it to the 2311 * caller. However, a subclass must not modify it after it has 2312 * been returned by <code>getCandidateLocales</code>. 2313 * 2314 * <p>For example, if the given <code>baseName</code> is "Messages" 2315 * and the given <code>locale</code> is 2316 * <code>Locale("ja", "", "XX")</code>, then a 2317 * <code>List</code> of <code>Locale</code>s: 2318 * <pre> 2319 * Locale("ja", "", "XX") 2320 * Locale("ja") 2321 * Locale.ROOT 2322 * </pre> 2323 * is returned. And if the resource bundles for the "ja" and 2324 * "" <code>Locale</code>s are found, then the runtime resource 2325 * lookup path (parent chain) is: 2326 * <pre>{@code 2327 * Messages_ja -> Messages 2328 * }</pre> 2329 * 2330 * @param baseName 2331 * the base name of the resource bundle, a fully 2332 * qualified class name 2333 * @param locale 2334 * the locale for which a resource bundle is desired 2335 * @return a <code>List</code> of candidate 2336 * <code>Locale</code>s for the given <code>locale</code> 2337 * @exception NullPointerException 2338 * if <code>baseName</code> or <code>locale</code> is 2339 * <code>null</code> 2340 */ 2341 public List<Locale> getCandidateLocales(String baseName, Locale locale) { 2342 if (baseName == null) { 2343 throw new NullPointerException(); 2344 } 2345 return new ArrayList<>(CANDIDATES_CACHE.get(locale.getBaseLocale())); 2346 } 2347 2348 private static final CandidateListCache CANDIDATES_CACHE = new CandidateListCache(); 2349 2350 private static class CandidateListCache extends LocaleObjectCache<BaseLocale, List<Locale>> { 2351 protected List<Locale> createObject(BaseLocale base) { 2352 String language = base.getLanguage(); 2353 String script = base.getScript(); 2354 String region = base.getRegion(); 2355 String variant = base.getVariant(); 2356 2357 // Special handling for Norwegian 2358 boolean isNorwegianBokmal = false; 2359 boolean isNorwegianNynorsk = false; 2360 if (language.equals("no")) { 2361 if (region.equals("NO") && variant.equals("NY")) { 2362 variant = ""; 2363 isNorwegianNynorsk = true; 2364 } else { 2365 isNorwegianBokmal = true; 2366 } 2367 } 2368 if (language.equals("nb") || isNorwegianBokmal) { 2369 List<Locale> tmpList = getDefaultList("nb", script, region, variant); 2370 // Insert a locale replacing "nb" with "no" for every list entry 2371 List<Locale> bokmalList = new LinkedList<>(); 2372 for (Locale l : tmpList) { 2373 bokmalList.add(l); 2374 if (l.getLanguage().length() == 0) { 2375 break; 2376 } 2377 bokmalList.add(Locale.getInstance("no", l.getScript(), l.getCountry(), 2378 l.getVariant(), null)); 2379 } 2380 return bokmalList; 2381 } else if (language.equals("nn") || isNorwegianNynorsk) { 2382 // Insert no_NO_NY, no_NO, no after nn 2383 List<Locale> nynorskList = getDefaultList("nn", script, region, variant); 2384 int idx = nynorskList.size() - 1; 2385 nynorskList.add(idx++, Locale.getInstance("no", "NO", "NY")); 2386 nynorskList.add(idx++, Locale.getInstance("no", "NO", "")); 2387 nynorskList.add(idx++, Locale.getInstance("no", "", "")); 2388 return nynorskList; 2389 } 2390 // Special handling for Chinese 2391 else if (language.equals("zh")) { 2392 if (script.length() == 0 && region.length() > 0) { 2393 // Supply script for users who want to use zh_Hans/zh_Hant 2394 // as bundle names (recommended for Java7+) 2395 switch (region) { 2396 case "TW": 2397 case "HK": 2398 case "MO": 2399 script = "Hant"; 2400 break; 2401 case "CN": 2402 case "SG": 2403 script = "Hans"; 2404 break; 2405 } 2406 } else if (script.length() > 0 && region.length() == 0) { 2407 // Supply region(country) for users who still package Chinese 2408 // bundles using old convension. 2409 switch (script) { 2410 case "Hans": 2411 region = "CN"; 2412 break; 2413 case "Hant": 2414 region = "TW"; 2415 break; 2416 } 2417 } 2418 } 2419 2420 return getDefaultList(language, script, region, variant); 2421 } 2422 2423 private static List<Locale> getDefaultList(String language, String script, String region, String variant) { 2424 List<String> variants = null; 2425 2426 if (variant.length() > 0) { 2427 variants = new LinkedList<>(); 2428 int idx = variant.length(); 2429 while (idx != -1) { 2430 variants.add(variant.substring(0, idx)); 2431 idx = variant.lastIndexOf('_', --idx); 2432 } 2433 } 2434 2435 List<Locale> list = new LinkedList<>(); 2436 2437 if (variants != null) { 2438 for (String v : variants) { 2439 list.add(Locale.getInstance(language, script, region, v, null)); 2440 } 2441 } 2442 if (region.length() > 0) { 2443 list.add(Locale.getInstance(language, script, region, "", null)); 2444 } 2445 if (script.length() > 0) { 2446 list.add(Locale.getInstance(language, script, "", "", null)); 2447 2448 // With script, after truncating variant, region and script, 2449 // start over without script. 2450 if (variants != null) { 2451 for (String v : variants) { 2452 list.add(Locale.getInstance(language, "", region, v, null)); 2453 } 2454 } 2455 if (region.length() > 0) { 2456 list.add(Locale.getInstance(language, "", region, "", null)); 2457 } 2458 } 2459 if (language.length() > 0) { 2460 list.add(Locale.getInstance(language, "", "", "", null)); 2461 } 2462 // Add root locale at the end 2463 list.add(Locale.ROOT); 2464 2465 return list; 2466 } 2467 } 2468 2469 /** 2470 * Returns a <code>Locale</code> to be used as a fallback locale for 2471 * further resource bundle searches by the 2472 * <code>ResourceBundle.getBundle</code> factory method. This method 2473 * is called from the factory method every time when no resulting 2474 * resource bundle has been found for <code>baseName</code> and 2475 * <code>locale</code>, where locale is either the parameter for 2476 * <code>ResourceBundle.getBundle</code> or the previous fallback 2477 * locale returned by this method. 2478 * 2479 * <p>The method returns <code>null</code> if no further fallback 2480 * search is desired. 2481 * 2482 * <p>The default implementation returns the {@linkplain 2483 * Locale#getDefault() default <code>Locale</code>} if the given 2484 * <code>locale</code> isn't the default one. Otherwise, 2485 * <code>null</code> is returned. 2486 * 2487 * @param baseName 2488 * the base name of the resource bundle, a fully 2489 * qualified class name for which 2490 * <code>ResourceBundle.getBundle</code> has been 2491 * unable to find any resource bundles (except for the 2492 * base bundle) 2493 * @param locale 2494 * the <code>Locale</code> for which 2495 * <code>ResourceBundle.getBundle</code> has been 2496 * unable to find any resource bundles (except for the 2497 * base bundle) 2498 * @return a <code>Locale</code> for the fallback search, 2499 * or <code>null</code> if no further fallback search 2500 * is desired. 2501 * @exception NullPointerException 2502 * if <code>baseName</code> or <code>locale</code> 2503 * is <code>null</code> 2504 */ 2505 public Locale getFallbackLocale(String baseName, Locale locale) { 2506 if (baseName == null) { 2507 throw new NullPointerException(); 2508 } 2509 Locale defaultLocale = Locale.getDefault(); 2510 return locale.equals(defaultLocale) ? null : defaultLocale; 2511 } 2512 2513 /** 2514 * Instantiates a resource bundle for the given bundle name of the 2515 * given format and locale, using the given class loader if 2516 * necessary. This method returns <code>null</code> if there is no 2517 * resource bundle available for the given parameters. If a resource 2518 * bundle can't be instantiated due to an unexpected error, the 2519 * error must be reported by throwing an <code>Error</code> or 2520 * <code>Exception</code> rather than simply returning 2521 * <code>null</code>. 2522 * 2523 * <p>If the <code>reload</code> flag is <code>true</code>, it 2524 * indicates that this method is being called because the previously 2525 * loaded resource bundle has expired. 2526 * 2527 * <p>The default implementation instantiates a 2528 * <code>ResourceBundle</code> as follows. 2529 * 2530 * <ul> 2531 * 2532 * <li>The bundle name is obtained by calling {@link 2533 * #toBundleName(String, Locale) toBundleName(baseName, 2534 * locale)}.</li> 2535 * 2536 * <li>If <code>format</code> is <code>"java.class"</code>, the 2537 * {@link Class} specified by the bundle name is loaded by calling 2538 * {@link ClassLoader#loadClass(String)}. Then, a 2539 * <code>ResourceBundle</code> is instantiated by calling {@link 2540 * Class#newInstance()}. Note that the <code>reload</code> flag is 2541 * ignored for loading class-based resource bundles in this default 2542 * implementation.</li> 2543 * 2544 * <li>If <code>format</code> is <code>"java.properties"</code>, 2545 * {@link #toResourceName(String, String) toResourceName(bundlename, 2546 * "properties")} is called to get the resource name. 2547 * If <code>reload</code> is <code>true</code>, {@link 2548 * ClassLoader#getResource(String) load.getResource} is called 2549 * to get a {@link URL} for creating a {@link 2550 * URLConnection}. This <code>URLConnection</code> is used to 2551 * {@linkplain URLConnection#setUseCaches(boolean) disable the 2552 * caches} of the underlying resource loading layers, 2553 * and to {@linkplain URLConnection#getInputStream() get an 2554 * <code>InputStream</code>}. 2555 * Otherwise, {@link ClassLoader#getResourceAsStream(String) 2556 * loader.getResourceAsStream} is called to get an {@link 2557 * InputStream}. Then, a {@link 2558 * PropertyResourceBundle} is constructed with the 2559 * <code>InputStream</code>.</li> 2560 * 2561 * <li>If <code>format</code> is neither <code>"java.class"</code> 2562 * nor <code>"java.properties"</code>, an 2563 * <code>IllegalArgumentException</code> is thrown.</li> 2564 * 2565 * </ul> 2566 * 2567 * @param baseName 2568 * the base bundle name of the resource bundle, a fully 2569 * qualified class name 2570 * @param locale 2571 * the locale for which the resource bundle should be 2572 * instantiated 2573 * @param format 2574 * the resource bundle format to be loaded 2575 * @param loader 2576 * the <code>ClassLoader</code> to use to load the bundle 2577 * @param reload 2578 * the flag to indicate bundle reloading; <code>true</code> 2579 * if reloading an expired resource bundle, 2580 * <code>false</code> otherwise 2581 * @return the resource bundle instance, 2582 * or <code>null</code> if none could be found. 2583 * @exception NullPointerException 2584 * if <code>bundleName</code>, <code>locale</code>, 2585 * <code>format</code>, or <code>loader</code> is 2586 * <code>null</code>, or if <code>null</code> is returned by 2587 * {@link #toBundleName(String, Locale) toBundleName} 2588 * @exception IllegalArgumentException 2589 * if <code>format</code> is unknown, or if the resource 2590 * found for the given parameters contains malformed data. 2591 * @exception ClassCastException 2592 * if the loaded class cannot be cast to <code>ResourceBundle</code> 2593 * @exception IllegalAccessException 2594 * if the class or its nullary constructor is not 2595 * accessible. 2596 * @exception InstantiationException 2597 * if the instantiation of a class fails for some other 2598 * reason. 2599 * @exception ExceptionInInitializerError 2600 * if the initialization provoked by this method fails. 2601 * @exception SecurityException 2602 * If a security manager is present and creation of new 2603 * instances is denied. See {@link Class#newInstance()} 2604 * for details. 2605 * @exception IOException 2606 * if an error occurred when reading resources using 2607 * any I/O operations 2608 */ 2609 public ResourceBundle newBundle(String baseName, Locale locale, String format, 2610 ClassLoader loader, boolean reload) 2611 throws IllegalAccessException, InstantiationException, IOException { 2612 String bundleName = toBundleName(baseName, locale); 2613 ResourceBundle bundle = null; 2614 if (format.equals("java.class")) { 2615 try { 2616 @SuppressWarnings("unchecked") 2617 Class<? extends ResourceBundle> bundleClass 2618 = (Class<? extends ResourceBundle>)loader.loadClass(bundleName); 2619 2620 // If the class isn't a ResourceBundle subclass, throw a 2621 // ClassCastException. 2622 if (ResourceBundle.class.isAssignableFrom(bundleClass)) { 2623 bundle = bundleClass.newInstance(); 2624 } else { 2625 throw new ClassCastException(bundleClass.getName() 2626 + " cannot be cast to ResourceBundle"); 2627 } 2628 } catch (ClassNotFoundException e) { 2629 } 2630 } else if (format.equals("java.properties")) { 2631 final String resourceName = toResourceName(bundleName, "properties"); 2632 final ClassLoader classLoader = loader; 2633 final boolean reloadFlag = reload; 2634 InputStream stream = null; 2635 try { 2636 stream = AccessController.doPrivileged( 2637 new PrivilegedExceptionAction<InputStream>() { 2638 public InputStream run() throws IOException { 2639 InputStream is = null; 2640 if (reloadFlag) { 2641 URL url = classLoader.getResource(resourceName); 2642 if (url != null) { 2643 URLConnection connection = url.openConnection(); 2644 if (connection != null) { 2645 // Disable caches to get fresh data for 2646 // reloading. 2647 connection.setUseCaches(false); 2648 is = connection.getInputStream(); 2649 } 2650 } 2651 } else { 2652 is = classLoader.getResourceAsStream(resourceName); 2653 } 2654 return is; 2655 } 2656 }); 2657 } catch (PrivilegedActionException e) { 2658 throw (IOException) e.getException(); 2659 } 2660 if (stream != null) { 2661 try { 2662 bundle = new PropertyResourceBundle(stream); 2663 } finally { 2664 stream.close(); 2665 } 2666 } 2667 } else { 2668 throw new IllegalArgumentException("unknown format: " + format); 2669 } 2670 return bundle; 2671 } 2672 2673 /** 2674 * Returns the time-to-live (TTL) value for resource bundles that 2675 * are loaded under this 2676 * <code>ResourceBundle.Control</code>. Positive time-to-live values 2677 * specify the number of milliseconds a bundle can remain in the 2678 * cache without being validated against the source data from which 2679 * it was constructed. The value 0 indicates that a bundle must be 2680 * validated each time it is retrieved from the cache. {@link 2681 * #TTL_DONT_CACHE} specifies that loaded resource bundles are not 2682 * put in the cache. {@link #TTL_NO_EXPIRATION_CONTROL} specifies 2683 * that loaded resource bundles are put in the cache with no 2684 * expiration control. 2685 * 2686 * <p>The expiration affects only the bundle loading process by the 2687 * <code>ResourceBundle.getBundle</code> factory method. That is, 2688 * if the factory method finds a resource bundle in the cache that 2689 * has expired, the factory method calls the {@link 2690 * #needsReload(String, Locale, String, ClassLoader, ResourceBundle, 2691 * long) needsReload} method to determine whether the resource 2692 * bundle needs to be reloaded. If <code>needsReload</code> returns 2693 * <code>true</code>, the cached resource bundle instance is removed 2694 * from the cache. Otherwise, the instance stays in the cache, 2695 * updated with the new TTL value returned by this method. 2696 * 2697 * <p>All cached resource bundles are subject to removal from the 2698 * cache due to memory constraints of the runtime environment. 2699 * Returning a large positive value doesn't mean to lock loaded 2700 * resource bundles in the cache. 2701 * 2702 * <p>The default implementation returns {@link #TTL_NO_EXPIRATION_CONTROL}. 2703 * 2704 * @param baseName 2705 * the base name of the resource bundle for which the 2706 * expiration value is specified. 2707 * @param locale 2708 * the locale of the resource bundle for which the 2709 * expiration value is specified. 2710 * @return the time (0 or a positive millisecond offset from the 2711 * cached time) to get loaded bundles expired in the cache, 2712 * {@link #TTL_NO_EXPIRATION_CONTROL} to disable the 2713 * expiration control, or {@link #TTL_DONT_CACHE} to disable 2714 * caching. 2715 * @exception NullPointerException 2716 * if <code>baseName</code> or <code>locale</code> is 2717 * <code>null</code> 2718 */ 2719 public long getTimeToLive(String baseName, Locale locale) { 2720 if (baseName == null || locale == null) { 2721 throw new NullPointerException(); 2722 } 2723 return TTL_NO_EXPIRATION_CONTROL; 2724 } 2725 2726 /** 2727 * Determines if the expired <code>bundle</code> in the cache needs 2728 * to be reloaded based on the loading time given by 2729 * <code>loadTime</code> or some other criteria. The method returns 2730 * <code>true</code> if reloading is required; <code>false</code> 2731 * otherwise. <code>loadTime</code> is a millisecond offset since 2732 * the <a href="Calendar.html#Epoch"> <code>Calendar</code> 2733 * Epoch</a>. 2734 * 2735 * The calling <code>ResourceBundle.getBundle</code> factory method 2736 * calls this method on the <code>ResourceBundle.Control</code> 2737 * instance used for its current invocation, not on the instance 2738 * used in the invocation that originally loaded the resource 2739 * bundle. 2740 * 2741 * <p>The default implementation compares <code>loadTime</code> and 2742 * the last modified time of the source data of the resource 2743 * bundle. If it's determined that the source data has been modified 2744 * since <code>loadTime</code>, <code>true</code> is 2745 * returned. Otherwise, <code>false</code> is returned. This 2746 * implementation assumes that the given <code>format</code> is the 2747 * same string as its file suffix if it's not one of the default 2748 * formats, <code>"java.class"</code> or 2749 * <code>"java.properties"</code>. 2750 * 2751 * @param baseName 2752 * the base bundle name of the resource bundle, a 2753 * fully qualified class name 2754 * @param locale 2755 * the locale for which the resource bundle 2756 * should be instantiated 2757 * @param format 2758 * the resource bundle format to be loaded 2759 * @param loader 2760 * the <code>ClassLoader</code> to use to load the bundle 2761 * @param bundle 2762 * the resource bundle instance that has been expired 2763 * in the cache 2764 * @param loadTime 2765 * the time when <code>bundle</code> was loaded and put 2766 * in the cache 2767 * @return <code>true</code> if the expired bundle needs to be 2768 * reloaded; <code>false</code> otherwise. 2769 * @exception NullPointerException 2770 * if <code>baseName</code>, <code>locale</code>, 2771 * <code>format</code>, <code>loader</code>, or 2772 * <code>bundle</code> is <code>null</code> 2773 */ 2774 public boolean needsReload(String baseName, Locale locale, 2775 String format, ClassLoader loader, 2776 ResourceBundle bundle, long loadTime) { 2777 if (bundle == null) { 2778 throw new NullPointerException(); 2779 } 2780 if (format.equals("java.class") || format.equals("java.properties")) { 2781 format = format.substring(5); 2782 } 2783 boolean result = false; 2784 try { 2785 String resourceName = toResourceName(toBundleName(baseName, locale), format); 2786 URL url = loader.getResource(resourceName); 2787 if (url != null) { 2788 long lastModified = 0; 2789 URLConnection connection = url.openConnection(); 2790 if (connection != null) { 2791 // disable caches to get the correct data 2792 connection.setUseCaches(false); 2793 if (connection instanceof JarURLConnection) { 2794 JarEntry ent = ((JarURLConnection)connection).getJarEntry(); 2795 if (ent != null) { 2796 lastModified = ent.getTime(); 2797 if (lastModified == -1) { 2798 lastModified = 0; 2799 } 2800 } 2801 } else { 2802 lastModified = connection.getLastModified(); 2803 } 2804 } 2805 result = lastModified >= loadTime; 2806 } 2807 } catch (NullPointerException npe) { 2808 throw npe; 2809 } catch (Exception e) { 2810 // ignore other exceptions 2811 } 2812 return result; 2813 } 2814 2815 /** 2816 * Converts the given <code>baseName</code> and <code>locale</code> 2817 * to the bundle name. This method is called from the default 2818 * implementation of the {@link #newBundle(String, Locale, String, 2819 * ClassLoader, boolean) newBundle} and {@link #needsReload(String, 2820 * Locale, String, ClassLoader, ResourceBundle, long) needsReload} 2821 * methods. 2822 * 2823 * <p>This implementation returns the following value: 2824 * <pre> 2825 * baseName + "_" + language + "_" + script + "_" + country + "_" + variant 2826 * </pre> 2827 * where <code>language</code>, <code>script</code>, <code>country</code>, 2828 * and <code>variant</code> are the language, script, country, and variant 2829 * values of <code>locale</code>, respectively. Final component values that 2830 * are empty Strings are omitted along with the preceding '_'. When the 2831 * script is empty, the script value is ommitted along with the preceding '_'. 2832 * If all of the values are empty strings, then <code>baseName</code> 2833 * is returned. 2834 * 2835 * <p>For example, if <code>baseName</code> is 2836 * <code>"baseName"</code> and <code>locale</code> is 2837 * <code>Locale("ja", "", "XX")</code>, then 2838 * <code>"baseName_ja_ _XX"</code> is returned. If the given 2839 * locale is <code>Locale("en")</code>, then 2840 * <code>"baseName_en"</code> is returned. 2841 * 2842 * <p>Overriding this method allows applications to use different 2843 * conventions in the organization and packaging of localized 2844 * resources. 2845 * 2846 * @param baseName 2847 * the base name of the resource bundle, a fully 2848 * qualified class name 2849 * @param locale 2850 * the locale for which a resource bundle should be 2851 * loaded 2852 * @return the bundle name for the resource bundle 2853 * @exception NullPointerException 2854 * if <code>baseName</code> or <code>locale</code> 2855 * is <code>null</code> 2856 */ 2857 public String toBundleName(String baseName, Locale locale) { 2858 if (locale == Locale.ROOT) { 2859 return baseName; 2860 } 2861 2862 String language = locale.getLanguage(); 2863 String script = locale.getScript(); 2864 String country = locale.getCountry(); 2865 String variant = locale.getVariant(); 2866 2867 if (language == "" && country == "" && variant == "") { 2868 return baseName; 2869 } 2870 2871 StringBuilder sb = new StringBuilder(baseName); 2872 sb.append('_'); 2873 if (script != "") { 2874 if (variant != "") { 2875 sb.append(language).append('_').append(script).append('_').append(country).append('_').append(variant); 2876 } else if (country != "") { 2877 sb.append(language).append('_').append(script).append('_').append(country); 2878 } else { 2879 sb.append(language).append('_').append(script); 2880 } 2881 } else { 2882 if (variant != "") { 2883 sb.append(language).append('_').append(country).append('_').append(variant); 2884 } else if (country != "") { 2885 sb.append(language).append('_').append(country); 2886 } else { 2887 sb.append(language); 2888 } 2889 } 2890 return sb.toString(); 2891 2892 } 2893 2894 /** 2895 * Converts the given <code>bundleName</code> to the form required 2896 * by the {@link ClassLoader#getResource ClassLoader.getResource} 2897 * method by replacing all occurrences of <code>'.'</code> in 2898 * <code>bundleName</code> with <code>'/'</code> and appending a 2899 * <code>'.'</code> and the given file <code>suffix</code>. For 2900 * example, if <code>bundleName</code> is 2901 * <code>"foo.bar.MyResources_ja_JP"</code> and <code>suffix</code> 2902 * is <code>"properties"</code>, then 2903 * <code>"foo/bar/MyResources_ja_JP.properties"</code> is returned. 2904 * 2905 * @param bundleName 2906 * the bundle name 2907 * @param suffix 2908 * the file type suffix 2909 * @return the converted resource name 2910 * @exception NullPointerException 2911 * if <code>bundleName</code> or <code>suffix</code> 2912 * is <code>null</code> 2913 */ 2914 public final String toResourceName(String bundleName, String suffix) { 2915 StringBuilder sb = new StringBuilder(bundleName.length() + 1 + suffix.length()); 2916 sb.append(bundleName.replace('.', '/')).append('.').append(suffix); 2917 return sb.toString(); 2918 } 2919 } 2920 2921 private static class SingleFormatControl extends Control { 2922 private static final Control PROPERTIES_ONLY 2923 = new SingleFormatControl(FORMAT_PROPERTIES); 2924 2925 private static final Control CLASS_ONLY 2926 = new SingleFormatControl(FORMAT_CLASS); 2927 2928 private final List<String> formats; 2929 2930 protected SingleFormatControl(List<String> formats) { 2931 this.formats = formats; 2932 } 2933 2934 public List<String> getFormats(String baseName) { 2935 if (baseName == null) { 2936 throw new NullPointerException(); 2937 } 2938 return formats; 2939 } 2940 } 2941 2942 private static final class NoFallbackControl extends SingleFormatControl { 2943 private static final Control NO_FALLBACK 2944 = new NoFallbackControl(FORMAT_DEFAULT); 2945 2946 private static final Control PROPERTIES_ONLY_NO_FALLBACK 2947 = new NoFallbackControl(FORMAT_PROPERTIES); 2948 2949 private static final Control CLASS_ONLY_NO_FALLBACK 2950 = new NoFallbackControl(FORMAT_CLASS); 2951 2952 protected NoFallbackControl(List<String> formats) { 2953 super(formats); 2954 } 2955 2956 public Locale getFallbackLocale(String baseName, Locale locale) { 2957 if (baseName == null || locale == null) { 2958 throw new NullPointerException(); 2959 } 2960 return null; 2961 } 2962 } 2963 }