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