Locale.getDefault() reads real value from navigator.language & co.
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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;
53 * Resource bundles contain locale-specific objects. When your program needs a
54 * locale-specific resource, a <code>String</code> for example, your program can
55 * load it from the resource bundle that is appropriate for the current user's
56 * locale. In this way, you can write program code that is largely independent
57 * of the user's locale isolating most, if not all, of the locale-specific
58 * information in resource bundles.
61 * This allows you to write programs that can:
63 * <LI> be easily localized, or translated, into different languages
64 * <LI> handle multiple locales at once
65 * <LI> be easily modified later to support even more locales
69 * Resource bundles belong to families whose members share a common base
70 * name, but whose names also have additional components that identify
71 * their locales. For example, the base name of a family of resource
72 * bundles might be "MyResources". The family should have a default
73 * resource bundle which simply has the same name as its family -
74 * "MyResources" - and will be used as the bundle of last resort if a
75 * specific locale is not supported. The family can then provide as
76 * many locale-specific members as needed, for example a German one
77 * named "MyResources_de".
80 * Each resource bundle in a family contains the same items, but the items have
81 * been translated for the locale represented by that resource bundle.
82 * For example, both "MyResources" and "MyResources_de" may have a
83 * <code>String</code> that's used on a button for canceling operations.
84 * In "MyResources" the <code>String</code> may contain "Cancel" and in
85 * "MyResources_de" it may contain "Abbrechen".
88 * If there are different resources for different countries, you
89 * can make specializations: for example, "MyResources_de_CH" contains objects for
90 * the German language (de) in Switzerland (CH). If you want to only
91 * modify some of the resources
92 * in the specialization, you can do so.
95 * When your program needs a locale-specific object, it loads
96 * the <code>ResourceBundle</code> class using the
97 * {@link #getBundle(java.lang.String, java.util.Locale) getBundle}
101 * ResourceBundle myResources =
102 * ResourceBundle.getBundle("MyResources", currentLocale);
107 * Resource bundles contain key/value pairs. The keys uniquely
108 * identify a locale-specific object in the bundle. Here's an
109 * example of a <code>ListResourceBundle</code> that contains
110 * two key/value pairs:
113 * public class MyResources extends ListResourceBundle {
114 * protected Object[][] getContents() {
115 * return new Object[][] {
116 * // LOCALIZE THE SECOND STRING OF EACH ARRAY (e.g., "OK")
118 * {"CancelKey", "Cancel"},
119 * // END OF MATERIAL TO LOCALIZE
125 * Keys are always <code>String</code>s.
126 * In this example, the keys are "OkKey" and "CancelKey".
127 * In the above example, the values
128 * are also <code>String</code>s--"OK" and "Cancel"--but
129 * they don't have to be. The values can be any type of object.
132 * You retrieve an object from resource bundle using the appropriate
133 * getter method. Because "OkKey" and "CancelKey"
134 * are both strings, you would use <code>getString</code> to retrieve them:
137 * button1 = new Button(myResources.getString("OkKey"));
138 * button2 = new Button(myResources.getString("CancelKey"));
141 * The getter methods all require the key as an argument and return
142 * the object if found. If the object is not found, the getter method
143 * throws a <code>MissingResourceException</code>.
146 * Besides <code>getString</code>, <code>ResourceBundle</code> also provides
147 * a method for getting string arrays, <code>getStringArray</code>,
148 * as well as a generic <code>getObject</code> method for any other
149 * type of object. When using <code>getObject</code>, you'll
150 * have to cast the result to the appropriate type. For example:
153 * int[] myIntegers = (int[]) myResources.getObject("intList");
158 * The Java Platform provides two subclasses of <code>ResourceBundle</code>,
159 * <code>ListResourceBundle</code> and <code>PropertyResourceBundle</code>,
160 * that provide a fairly simple way to create resources.
161 * As you saw briefly in a previous example, <code>ListResourceBundle</code>
162 * manages its resource as a list of key/value pairs.
163 * <code>PropertyResourceBundle</code> uses a properties file to manage
167 * If <code>ListResourceBundle</code> or <code>PropertyResourceBundle</code>
168 * do not suit your needs, you can write your own <code>ResourceBundle</code>
169 * subclass. Your subclasses must override two methods: <code>handleGetObject</code>
170 * and <code>getKeys()</code>.
172 * <h4>ResourceBundle.Control</h4>
174 * The {@link ResourceBundle.Control} class provides information necessary
175 * to perform the bundle loading process by the <code>getBundle</code>
176 * factory methods that take a <code>ResourceBundle.Control</code>
177 * instance. You can implement your own subclass in order to enable
178 * non-standard resource bundle formats, change the search strategy, or
179 * define caching parameters. Refer to the descriptions of the class and the
180 * {@link #getBundle(String, Locale, ClassLoader, Control) getBundle}
181 * factory method for details.
183 * <h4>Cache Management</h4>
185 * Resource bundle instances created by the <code>getBundle</code> factory
186 * methods are cached by default, and the factory methods return the same
187 * resource bundle instance multiple times if it has been
188 * cached. <code>getBundle</code> clients may clear the cache, manage the
189 * lifetime of cached resource bundle instances using time-to-live values,
190 * or specify not to cache resource bundle instances. Refer to the
191 * descriptions of the {@linkplain #getBundle(String, Locale, ClassLoader,
192 * Control) <code>getBundle</code> factory method}, {@link
193 * #clearCache(ClassLoader) clearCache}, {@link
194 * Control#getTimeToLive(String, Locale)
195 * ResourceBundle.Control.getTimeToLive}, and {@link
196 * Control#needsReload(String, Locale, String, ClassLoader, ResourceBundle,
197 * long) ResourceBundle.Control.needsReload} for details.
201 * The following is a very simple example of a <code>ResourceBundle</code>
202 * subclass, <code>MyResources</code>, that manages two resources (for a larger number of
203 * resources you would probably use a <code>Map</code>).
204 * Notice that you don't need to supply a value if
205 * a "parent-level" <code>ResourceBundle</code> handles the same
206 * key with the same value (as for the okKey below).
209 * // default (English language, United States)
210 * public class MyResources extends ResourceBundle {
211 * public Object handleGetObject(String key) {
212 * if (key.equals("okKey")) return "Ok";
213 * if (key.equals("cancelKey")) return "Cancel";
217 * public Enumeration<String> getKeys() {
218 * return Collections.enumeration(keySet());
221 * // Overrides handleKeySet() so that the getKeys() implementation
222 * // can rely on the keySet() value.
223 * protected Set<String> handleKeySet() {
224 * return new HashSet<String>(Arrays.asList("okKey", "cancelKey"));
229 * public class MyResources_de extends MyResources {
230 * public Object handleGetObject(String key) {
231 * // don't need okKey, since parent level handles it.
232 * if (key.equals("cancelKey")) return "Abbrechen";
236 * protected Set<String> handleKeySet() {
237 * return new HashSet<String>(Arrays.asList("cancelKey"));
242 * You do not have to restrict yourself to using a single family of
243 * <code>ResourceBundle</code>s. For example, you could have a set of bundles for
244 * exception messages, <code>ExceptionResources</code>
245 * (<code>ExceptionResources_fr</code>, <code>ExceptionResources_de</code>, ...),
246 * and one for widgets, <code>WidgetResource</code> (<code>WidgetResources_fr</code>,
247 * <code>WidgetResources_de</code>, ...); breaking up the resources however you like.
249 * @see ListResourceBundle
250 * @see PropertyResourceBundle
251 * @see MissingResourceException
254 public abstract class ResourceBundle {
256 /** initial size of the bundle cache */
257 private static final int INITIAL_CACHE_SIZE = 32;
259 /** constant indicating that no resource bundle exists */
260 private static final ResourceBundle NONEXISTENT_BUNDLE = new ResourceBundle() {
261 public Enumeration<String> getKeys() { return null; }
262 protected Object handleGetObject(String key) { return null; }
263 public String toString() { return "NONEXISTENT_BUNDLE"; }
268 * The cache is a map from cache keys (with bundle base name, locale, and
269 * class loader) to either a resource bundle or NONEXISTENT_BUNDLE wrapped by a
272 * The cache is a ConcurrentMap, allowing the cache to be searched
273 * concurrently by multiple threads. This will also allow the cache keys
274 * to be reclaimed along with the ClassLoaders they reference.
276 * This variable would be better named "cache", but we keep the old
277 * name for compatibility with some workarounds for bug 4212439.
279 private static final Map<CacheKey, BundleReference> cacheList
280 = new HashMap<>(INITIAL_CACHE_SIZE);
283 * Queue for reference objects referring to class loaders or bundles.
285 private static final ReferenceQueue referenceQueue = new ReferenceQueue();
288 * The parent bundle of this bundle.
289 * The parent bundle is searched by {@link #getObject getObject}
290 * when this bundle does not contain a particular resource.
292 protected ResourceBundle parent = null;
295 * The locale for this bundle.
297 private Locale locale = null;
300 * The base bundle name for this bundle.
305 * The flag indicating this bundle has expired in the cache.
307 private volatile boolean expired;
310 * The back link to the cache key. null if this bundle isn't in
311 * the cache (yet) or has expired.
313 private volatile CacheKey cacheKey;
316 * A Set of the keys contained only in this ResourceBundle.
318 private volatile Set<String> keySet;
321 * Sole constructor. (For invocation by subclass constructors, typically
324 public ResourceBundle() {
328 * Gets a string for the given key from this resource bundle or one of its parents.
329 * Calling this method is equivalent to calling
331 * <code>(String) {@link #getObject(java.lang.String) getObject}(key)</code>.
334 * @param key the key for the desired string
335 * @exception NullPointerException if <code>key</code> is <code>null</code>
336 * @exception MissingResourceException if no object for the given key can be found
337 * @exception ClassCastException if the object found for the given key is not a string
338 * @return the string for the given key
340 public final String getString(String key) {
341 return (String) getObject(key);
345 * Gets a string array for the given key from this resource bundle or one of its parents.
346 * Calling this method is equivalent to calling
348 * <code>(String[]) {@link #getObject(java.lang.String) getObject}(key)</code>.
351 * @param key the key for the desired string array
352 * @exception NullPointerException if <code>key</code> is <code>null</code>
353 * @exception MissingResourceException if no object for the given key can be found
354 * @exception ClassCastException if the object found for the given key is not a string array
355 * @return the string array for the given key
357 public final String[] getStringArray(String key) {
358 return (String[]) getObject(key);
362 * Gets an object for the given key from this resource bundle or one of its parents.
363 * This method first tries to obtain the object from this resource bundle using
364 * {@link #handleGetObject(java.lang.String) handleGetObject}.
365 * If not successful, and the parent resource bundle is not null,
366 * it calls the parent's <code>getObject</code> method.
367 * If still not successful, it throws a MissingResourceException.
369 * @param key the key for the desired object
370 * @exception NullPointerException if <code>key</code> is <code>null</code>
371 * @exception MissingResourceException if no object for the given key can be found
372 * @return the object for the given key
374 public final Object getObject(String key) {
375 Object obj = handleGetObject(key);
377 if (parent != null) {
378 obj = parent.getObject(key);
381 throw new MissingResourceException("Can't find resource for bundle "
382 +this.getClass().getName()
384 this.getClass().getName(),
391 * Returns the locale of this resource bundle. This method can be used after a
392 * call to getBundle() to determine whether the resource bundle returned really
393 * corresponds to the requested locale or is a fallback.
395 * @return the locale of this resource bundle
397 public Locale getLocale() {
402 * Sets the parent bundle of this bundle.
403 * The parent bundle is searched by {@link #getObject getObject}
404 * when this bundle does not contain a particular resource.
406 * @param parent this bundle's parent bundle.
408 protected void setParent(ResourceBundle parent) {
409 assert parent != NONEXISTENT_BUNDLE;
410 this.parent = parent;
414 * Key used for cached resource bundles. The key checks the base
415 * name, the locale, and the class loader to determine if the
416 * resource is a match to the requested one. The loader may be
417 * null, but the base name and the locale must have a non-null
420 private static final class CacheKey implements Cloneable {
421 // These three are the actual keys for lookup in Map.
423 private Locale locale;
425 // bundle format which is necessary for calling
426 // Control.needsReload().
427 private String format;
429 // These time values are in CacheKey so that NONEXISTENT_BUNDLE
430 // doesn't need to be cloned for caching.
432 // The time when the bundle has been loaded
433 private volatile long loadTime;
435 // The time when the bundle expires in the cache, or either
436 // Control.TTL_DONT_CACHE or Control.TTL_NO_EXPIRATION_CONTROL.
437 private volatile long expirationTime;
439 // Placeholder for an error report by a Throwable
440 private Throwable cause;
442 // Hash code value cache to avoid recalculating the hash code
444 private int hashCodeCache;
446 CacheKey(String baseName, Locale locale) {
447 this.name = baseName;
448 this.locale = locale;
456 CacheKey setName(String baseName) {
457 if (!this.name.equals(baseName)) {
458 this.name = baseName;
468 CacheKey setLocale(Locale locale) {
469 if (!this.locale.equals(locale)) {
470 this.locale = locale;
476 public boolean equals(Object other) {
481 final CacheKey otherEntry = (CacheKey)other;
482 //quick check to see if they are not equal
483 if (hashCodeCache != otherEntry.hashCodeCache) {
486 //are the names the same?
487 if (!name.equals(otherEntry.name)) {
490 // are the locales the same?
491 if (!locale.equals(otherEntry.locale)) {
495 } catch (NullPointerException e) {
496 } catch (ClassCastException e) {
501 public int hashCode() {
502 return hashCodeCache;
505 private void calculateHashCode() {
506 hashCodeCache = name.hashCode() << 3;
507 hashCodeCache ^= locale.hashCode();
510 public Object clone() {
512 CacheKey clone = (CacheKey) super.clone();
513 // Clear the reference to a Throwable
516 } catch (CloneNotSupportedException e) {
517 //this should never happen
518 throw new InternalError();
526 void setFormat(String format) {
527 this.format = format;
530 private void setCause(Throwable cause) {
531 if (this.cause == null) {
534 // Override the cause if the previous one is
535 // ClassNotFoundException.
536 if (this.cause instanceof ClassNotFoundException) {
542 private Throwable getCause() {
546 public String toString() {
547 String l = locale.toString();
548 if (l.length() == 0) {
549 if (locale.getVariant().length() != 0) {
550 l = "__" + locale.getVariant();
555 return "CacheKey[" + name + ", lc=" + l
556 + "(format=" + format + ")]";
561 * The common interface to get a CacheKey in LoaderReference and
564 private static interface CacheKeyReference {
565 public CacheKey getCacheKey();
569 * References to bundles are soft references so that they can be garbage
570 * collected when they have no hard references.
572 private static final class BundleReference extends SoftReference<ResourceBundle>
573 implements CacheKeyReference {
574 private CacheKey cacheKey;
576 BundleReference(ResourceBundle referent, ReferenceQueue q, CacheKey key) {
581 public CacheKey getCacheKey() {
587 * Gets a resource bundle using the specified base name, the default locale,
588 * and the caller's class loader. Calling this method is equivalent to calling
590 * <code>getBundle(baseName, Locale.getDefault(), this.getClass().getClassLoader())</code>,
592 * except that <code>getClassLoader()</code> is run with the security
593 * privileges of <code>ResourceBundle</code>.
594 * See {@link #getBundle(String, Locale, ClassLoader) getBundle}
595 * for a complete description of the search and instantiation strategy.
597 * @param baseName the base name of the resource bundle, a fully qualified class name
598 * @exception java.lang.NullPointerException
599 * if <code>baseName</code> is <code>null</code>
600 * @exception MissingResourceException
601 * if no resource bundle for the specified base name can be found
602 * @return a resource bundle for the given base name and the default locale
604 public static final ResourceBundle getBundle(String baseName)
606 return getBundleImpl(baseName, Locale.getDefault(),
611 * Returns a resource bundle using the specified base name, the
612 * default locale and the specified control. Calling this method
613 * is equivalent to calling
615 * getBundle(baseName, Locale.getDefault(),
616 * this.getClass().getClassLoader(), control),
618 * except that <code>getClassLoader()</code> is run with the security
619 * privileges of <code>ResourceBundle</code>. See {@link
620 * #getBundle(String, Locale, ClassLoader, Control) getBundle} for the
621 * complete description of the resource bundle loading process with a
622 * <code>ResourceBundle.Control</code>.
625 * the base name of the resource bundle, a fully qualified class
628 * the control which gives information for the resource bundle
630 * @return a resource bundle for the given base name and the default
632 * @exception NullPointerException
633 * if <code>baseName</code> or <code>control</code> is
635 * @exception MissingResourceException
636 * if no resource bundle for the specified base name can be found
637 * @exception IllegalArgumentException
638 * if the given <code>control</code> doesn't perform properly
639 * (e.g., <code>control.getCandidateLocales</code> returns null.)
640 * Note that validation of <code>control</code> is performed as
644 public static final ResourceBundle getBundle(String baseName,
646 return getBundleImpl(baseName, Locale.getDefault(),
647 /* must determine loader here, else we break stack invariant */
652 * Gets a resource bundle using the specified base name and locale,
653 * and the caller's class loader. Calling this method is equivalent to calling
655 * <code>getBundle(baseName, locale, this.getClass().getClassLoader())</code>,
657 * except that <code>getClassLoader()</code> is run with the security
658 * privileges of <code>ResourceBundle</code>.
659 * See {@link #getBundle(String, Locale, ClassLoader) getBundle}
660 * for a complete description of the search and instantiation strategy.
663 * the base name of the resource bundle, a fully qualified class name
665 * the locale for which a resource bundle is desired
666 * @exception NullPointerException
667 * if <code>baseName</code> or <code>locale</code> is <code>null</code>
668 * @exception MissingResourceException
669 * if no resource bundle for the specified base name can be found
670 * @return a resource bundle for the given base name and locale
672 public static final ResourceBundle getBundle(String baseName,
675 return getBundleImpl(baseName, locale,
676 /* must determine loader here, else we break stack invariant */
681 * Returns a resource bundle using the specified base name, target
682 * locale and control, and the caller's class loader. Calling this
683 * method is equivalent to calling
685 * getBundle(baseName, targetLocale, this.getClass().getClassLoader(),
688 * except that <code>getClassLoader()</code> is run with the security
689 * privileges of <code>ResourceBundle</code>. See {@link
690 * #getBundle(String, Locale, ClassLoader, Control) getBundle} for the
691 * complete description of the resource bundle loading process with a
692 * <code>ResourceBundle.Control</code>.
695 * the base name of the resource bundle, a fully qualified
697 * @param targetLocale
698 * the locale for which a resource bundle is desired
700 * the control which gives information for the resource
701 * bundle loading process
702 * @return a resource bundle for the given base name and a
703 * <code>Locale</code> in <code>locales</code>
704 * @exception NullPointerException
705 * if <code>baseName</code>, <code>locales</code> or
706 * <code>control</code> is <code>null</code>
707 * @exception MissingResourceException
708 * if no resource bundle for the specified base name in any
709 * of the <code>locales</code> can be found.
710 * @exception IllegalArgumentException
711 * if the given <code>control</code> doesn't perform properly
712 * (e.g., <code>control.getCandidateLocales</code> returns null.)
713 * Note that validation of <code>control</code> is performed as
717 public static final ResourceBundle getBundle(String baseName, Locale targetLocale,
719 return getBundleImpl(baseName, targetLocale,
720 /* must determine loader here, else we break stack invariant */
725 * Gets a resource bundle using the specified base name, locale, and class
728 * <p><a name="default_behavior"/>This method behaves the same as calling
729 * {@link #getBundle(String, Locale, ClassLoader, Control)} passing a
730 * default instance of {@link Control}. The following describes this behavior.
732 * <p><code>getBundle</code> uses the base name, the specified locale, and
733 * the default locale (obtained from {@link java.util.Locale#getDefault()
734 * Locale.getDefault}) to generate a sequence of <a
735 * name="candidates"><em>candidate bundle names</em></a>. If the specified
736 * locale's language, script, country, and variant are all empty strings,
737 * then the base name is the only candidate bundle name. Otherwise, a list
738 * of candidate locales is generated from the attribute values of the
739 * specified locale (language, script, country and variant) and appended to
740 * the base name. Typically, this will look like the following:
743 * baseName + "_" + language + "_" + script + "_" + country + "_" + variant
744 * baseName + "_" + language + "_" + script + "_" + country
745 * baseName + "_" + language + "_" + script
746 * baseName + "_" + language + "_" + country + "_" + variant
747 * baseName + "_" + language + "_" + country
748 * baseName + "_" + language
751 * <p>Candidate bundle names where the final component is an empty string
752 * are omitted, along with the underscore. For example, if country is an
753 * empty string, the second and the fifth candidate bundle names above
754 * would be omitted. Also, if script is an empty string, the candidate names
755 * including script are omitted. For example, a locale with language "de"
756 * and variant "JAVA" will produce candidate names with base name
757 * "MyResource" below.
760 * MyResource_de__JAVA
764 * In the case that the variant contains one or more underscores ('_'), a
765 * sequence of bundle names generated by truncating the last underscore and
766 * the part following it is inserted after a candidate bundle name with the
767 * original variant. For example, for a locale with language "en", script
768 * "Latn, country "US" and variant "WINDOWS_VISTA", and bundle base name
769 * "MyResource", the list of candidate bundle names below is generated:
772 * MyResource_en_Latn_US_WINDOWS_VISTA
773 * MyResource_en_Latn_US_WINDOWS
774 * MyResource_en_Latn_US
776 * MyResource_en_US_WINDOWS_VISTA
777 * MyResource_en_US_WINDOWS
782 * <blockquote><b>Note:</b> For some <code>Locale</code>s, the list of
783 * candidate bundle names contains extra names, or the order of bundle names
784 * is slightly modified. See the description of the default implementation
785 * of {@link Control#getCandidateLocales(String, Locale)
786 * getCandidateLocales} for details.</blockquote>
788 * <p><code>getBundle</code> then iterates over the candidate bundle names
789 * to find the first one for which it can <em>instantiate</em> an actual
790 * resource bundle. It uses the default controls' {@link Control#getFormats
791 * getFormats} method, which generates two bundle names for each generated
792 * name, the first a class name and the second a properties file name. For
793 * each candidate bundle name, it attempts to create a resource bundle:
795 * <ul><li>First, it attempts to load a class using the generated class name.
796 * If such a class can be found and loaded using the specified class
797 * loader, is assignment compatible with ResourceBundle, is accessible from
798 * ResourceBundle, and can be instantiated, <code>getBundle</code> creates a
799 * new instance of this class and uses it as the <em>result resource
802 * <li>Otherwise, <code>getBundle</code> attempts to locate a property
803 * resource file using the generated properties file name. It generates a
804 * path name from the candidate bundle name by replacing all "." characters
805 * with "/" and appending the string ".properties". It attempts to find a
806 * "resource" with this name using {@link
807 * java.lang.ClassLoader#getResource(java.lang.String)
808 * ClassLoader.getResource}. (Note that a "resource" in the sense of
809 * <code>getResource</code> has nothing to do with the contents of a
810 * resource bundle, it is just a container of data, such as a file.) If it
811 * finds a "resource", it attempts to create a new {@link
812 * PropertyResourceBundle} instance from its contents. If successful, this
813 * instance becomes the <em>result resource bundle</em>. </ul>
815 * <p>This continues until a result resource bundle is instantiated or the
816 * list of candidate bundle names is exhausted. If no matching resource
817 * bundle is found, the default control's {@link Control#getFallbackLocale
818 * getFallbackLocale} method is called, which returns the current default
819 * locale. A new sequence of candidate locale names is generated using this
820 * locale and and searched again, as above.
822 * <p>If still no result bundle is found, the base name alone is looked up. If
823 * this still fails, a <code>MissingResourceException</code> is thrown.
825 * <p><a name="parent_chain"/> Once a result resource bundle has been found,
826 * its <em>parent chain</em> is instantiated. If the result bundle already
827 * has a parent (perhaps because it was returned from a cache) the chain is
830 * <p>Otherwise, <code>getBundle</code> examines the remainder of the
831 * candidate locale list that was used during the pass that generated the
832 * result resource bundle. (As before, candidate bundle names where the
833 * final component is an empty string are omitted.) When it comes to the
834 * end of the candidate list, it tries the plain bundle name. With each of the
835 * candidate bundle names it attempts to instantiate a resource bundle (first
836 * looking for a class and then a properties file, as described above).
838 * <p>Whenever it succeeds, it calls the previously instantiated resource
839 * bundle's {@link #setParent(java.util.ResourceBundle) setParent} method
840 * with the new resource bundle. This continues until the list of names
841 * is exhausted or the current bundle already has a non-null parent.
843 * <p>Once the parent chain is complete, the bundle is returned.
845 * <p><b>Note:</b> <code>getBundle</code> caches instantiated resource
846 * bundles and might return the same resource bundle instance multiple times.
848 * <p><b>Note:</b>The <code>baseName</code> argument should be a fully
849 * qualified class name. However, for compatibility with earlier versions,
850 * Sun's Java SE Runtime Environments do not verify this, and so it is
851 * possible to access <code>PropertyResourceBundle</code>s by specifying a
852 * path name (using "/") instead of a fully qualified class name (using
855 * <p><a name="default_behavior_example"/>
856 * <strong>Example:</strong>
858 * The following class and property files are provided:
861 * MyResources.properties
862 * MyResources_fr.properties
863 * MyResources_fr_CH.class
864 * MyResources_fr_CH.properties
865 * MyResources_en.properties
866 * MyResources_es_ES.class
869 * The contents of all files are valid (that is, public non-abstract
870 * subclasses of <code>ResourceBundle</code> for the ".class" files,
871 * syntactically correct ".properties" files). The default locale is
872 * <code>Locale("en", "GB")</code>.
874 * <p>Calling <code>getBundle</code> with the locale arguments below will
875 * instantiate resource bundles as follows:
878 * <tr><td>Locale("fr", "CH")</td><td>MyResources_fr_CH.class, parent MyResources_fr.properties, parent MyResources.class</td></tr>
879 * <tr><td>Locale("fr", "FR")</td><td>MyResources_fr.properties, parent MyResources.class</td></tr>
880 * <tr><td>Locale("de", "DE")</td><td>MyResources_en.properties, parent MyResources.class</td></tr>
881 * <tr><td>Locale("en", "US")</td><td>MyResources_en.properties, parent MyResources.class</td></tr>
882 * <tr><td>Locale("es", "ES")</td><td>MyResources_es_ES.class, parent MyResources.class</td></tr>
885 * <p>The file MyResources_fr_CH.properties is never used because it is
886 * hidden by the MyResources_fr_CH.class. Likewise, MyResources.properties
887 * is also hidden by MyResources.class.
889 * @param baseName the base name of the resource bundle, a fully qualified class name
890 * @param locale the locale for which a resource bundle is desired
891 * @param loader the class loader from which to load the resource bundle
892 * @return a resource bundle for the given base name and locale
893 * @exception java.lang.NullPointerException
894 * if <code>baseName</code>, <code>locale</code>, or <code>loader</code> is <code>null</code>
895 * @exception MissingResourceException
896 * if no resource bundle for the specified base name can be found
899 public static ResourceBundle getBundle(String baseName, Locale locale,
902 if (loader == null) {
903 throw new NullPointerException();
905 return getBundleImpl(baseName, locale, Control.INSTANCE);
909 * Returns a resource bundle using the specified base name, target
910 * locale, class loader and control. Unlike the {@linkplain
911 * #getBundle(String, Locale, ClassLoader) <code>getBundle</code>
912 * factory methods with no <code>control</code> argument}, the given
913 * <code>control</code> specifies how to locate and instantiate resource
914 * bundles. Conceptually, the bundle loading process with the given
915 * <code>control</code> is performed in the following steps.
919 * <li>This factory method looks up the resource bundle in the cache for
920 * the specified <code>baseName</code>, <code>targetLocale</code> and
921 * <code>loader</code>. If the requested resource bundle instance is
922 * found in the cache and the time-to-live periods of the instance and
923 * all of its parent instances have not expired, the instance is returned
924 * to the caller. Otherwise, this factory method proceeds with the
925 * loading process below.</li>
927 * <li>The {@link ResourceBundle.Control#getFormats(String)
928 * control.getFormats} method is called to get resource bundle formats
929 * to produce bundle or resource names. The strings
930 * <code>"java.class"</code> and <code>"java.properties"</code>
931 * designate class-based and {@linkplain PropertyResourceBundle
932 * property}-based resource bundles, respectively. Other strings
933 * starting with <code>"java."</code> are reserved for future extensions
934 * and must not be used for application-defined formats. Other strings
935 * designate application-defined formats.</li>
937 * <li>The {@link ResourceBundle.Control#getCandidateLocales(String,
938 * Locale) control.getCandidateLocales} method is called with the target
939 * locale to get a list of <em>candidate <code>Locale</code>s</em> for
940 * which resource bundles are searched.</li>
942 * <li>The {@link ResourceBundle.Control#newBundle(String, Locale,
943 * String, ClassLoader, boolean) control.newBundle} method is called to
944 * instantiate a <code>ResourceBundle</code> for the base bundle name, a
945 * candidate locale, and a format. (Refer to the note on the cache
946 * lookup below.) This step is iterated over all combinations of the
947 * candidate locales and formats until the <code>newBundle</code> method
948 * returns a <code>ResourceBundle</code> instance or the iteration has
949 * used up all the combinations. For example, if the candidate locales
950 * are <code>Locale("de", "DE")</code>, <code>Locale("de")</code> and
951 * <code>Locale("")</code> and the formats are <code>"java.class"</code>
952 * and <code>"java.properties"</code>, then the following is the
953 * sequence of locale-format combinations to be used to call
954 * <code>control.newBundle</code>.
956 * <table style="width: 50%; text-align: left; margin-left: 40px;"
957 * border="0" cellpadding="2" cellspacing="2">
961 * style="vertical-align: top; text-align: left; font-weight: bold; width: 50%;">Locale<br>
964 * style="vertical-align: top; text-align: left; font-weight: bold; width: 50%;">format<br>
968 * <td style="vertical-align: top; width: 50%;">Locale("de", "DE")<br>
970 * <td style="vertical-align: top; width: 50%;">java.class<br>
974 * <td style="vertical-align: top; width: 50%;">Locale("de", "DE")</td>
975 * <td style="vertical-align: top; width: 50%;">java.properties<br>
979 * <td style="vertical-align: top; width: 50%;">Locale("de")</td>
980 * <td style="vertical-align: top; width: 50%;">java.class</td>
983 * <td style="vertical-align: top; width: 50%;">Locale("de")</td>
984 * <td style="vertical-align: top; width: 50%;">java.properties</td>
987 * <td style="vertical-align: top; width: 50%;">Locale("")<br>
989 * <td style="vertical-align: top; width: 50%;">java.class</td>
992 * <td style="vertical-align: top; width: 50%;">Locale("")</td>
993 * <td style="vertical-align: top; width: 50%;">java.properties</td>
999 * <li>If the previous step has found no resource bundle, proceed to
1000 * Step 6. If a bundle has been found that is a base bundle (a bundle
1001 * for <code>Locale("")</code>), and the candidate locale list only contained
1002 * <code>Locale("")</code>, return the bundle to the caller. If a bundle
1003 * has been found that is a base bundle, but the candidate locale list
1004 * contained locales other than Locale(""), put the bundle on hold and
1005 * proceed to Step 6. If a bundle has been found that is not a base
1006 * bundle, proceed to Step 7.</li>
1008 * <li>The {@link ResourceBundle.Control#getFallbackLocale(String,
1009 * Locale) control.getFallbackLocale} method is called to get a fallback
1010 * locale (alternative to the current target locale) to try further
1011 * finding a resource bundle. If the method returns a non-null locale,
1012 * it becomes the next target locale and the loading process starts over
1013 * from Step 3. Otherwise, if a base bundle was found and put on hold in
1014 * a previous Step 5, it is returned to the caller now. Otherwise, a
1015 * MissingResourceException is thrown.</li>
1017 * <li>At this point, we have found a resource bundle that's not the
1018 * base bundle. If this bundle set its parent during its instantiation,
1019 * it is returned to the caller. Otherwise, its <a
1020 * href="./ResourceBundle.html#parent_chain">parent chain</a> is
1021 * instantiated based on the list of candidate locales from which it was
1022 * found. Finally, the bundle is returned to the caller.</li>
1025 * <p>During the resource bundle loading process above, this factory
1026 * method looks up the cache before calling the {@link
1027 * Control#newBundle(String, Locale, String, ClassLoader, boolean)
1028 * control.newBundle} method. If the time-to-live period of the
1029 * resource bundle found in the cache has expired, the factory method
1030 * calls the {@link ResourceBundle.Control#needsReload(String, Locale,
1031 * String, ClassLoader, ResourceBundle, long) control.needsReload}
1032 * method to determine whether the resource bundle needs to be reloaded.
1033 * If reloading is required, the factory method calls
1034 * <code>control.newBundle</code> to reload the resource bundle. If
1035 * <code>control.newBundle</code> returns <code>null</code>, the factory
1036 * method puts a dummy resource bundle in the cache as a mark of
1037 * nonexistent resource bundles in order to avoid lookup overhead for
1038 * subsequent requests. Such dummy resource bundles are under the same
1039 * expiration control as specified by <code>control</code>.
1041 * <p>All resource bundles loaded are cached by default. Refer to
1042 * {@link Control#getTimeToLive(String,Locale)
1043 * control.getTimeToLive} for details.
1045 * <p>The following is an example of the bundle loading process with the
1046 * default <code>ResourceBundle.Control</code> implementation.
1050 * <li>Base bundle name: <code>foo.bar.Messages</code>
1051 * <li>Requested <code>Locale</code>: {@link Locale#ITALY}</li>
1052 * <li>Default <code>Locale</code>: {@link Locale#FRENCH}</li>
1053 * <li>Available resource bundles:
1054 * <code>foo/bar/Messages_fr.properties</code> and
1055 * <code>foo/bar/Messages.properties</code></li>
1058 * <p>First, <code>getBundle</code> tries loading a resource bundle in
1059 * the following sequence.
1062 * <li>class <code>foo.bar.Messages_it_IT</code>
1063 * <li>file <code>foo/bar/Messages_it_IT.properties</code>
1064 * <li>class <code>foo.bar.Messages_it</code></li>
1065 * <li>file <code>foo/bar/Messages_it.properties</code></li>
1066 * <li>class <code>foo.bar.Messages</code></li>
1067 * <li>file <code>foo/bar/Messages.properties</code></li>
1070 * <p>At this point, <code>getBundle</code> finds
1071 * <code>foo/bar/Messages.properties</code>, which is put on hold
1072 * because it's the base bundle. <code>getBundle</code> calls {@link
1073 * Control#getFallbackLocale(String, Locale)
1074 * control.getFallbackLocale("foo.bar.Messages", Locale.ITALY)} which
1075 * returns <code>Locale.FRENCH</code>. Next, <code>getBundle</code>
1076 * tries loading a bundle in the following sequence.
1079 * <li>class <code>foo.bar.Messages_fr</code></li>
1080 * <li>file <code>foo/bar/Messages_fr.properties</code></li>
1081 * <li>class <code>foo.bar.Messages</code></li>
1082 * <li>file <code>foo/bar/Messages.properties</code></li>
1085 * <p><code>getBundle</code> finds
1086 * <code>foo/bar/Messages_fr.properties</code> and creates a
1087 * <code>ResourceBundle</code> instance. Then, <code>getBundle</code>
1088 * sets up its parent chain from the list of the candiate locales. Only
1089 * <code>foo/bar/Messages.properties</code> is found in the list and
1090 * <code>getBundle</code> creates a <code>ResourceBundle</code> instance
1091 * that becomes the parent of the instance for
1092 * <code>foo/bar/Messages_fr.properties</code>.
1095 * the base name of the resource bundle, a fully qualified
1097 * @param targetLocale
1098 * the locale for which a resource bundle is desired
1100 * the class loader from which to load the resource bundle
1102 * the control which gives information for the resource
1103 * bundle loading process
1104 * @return a resource bundle for the given base name and locale
1105 * @exception NullPointerException
1106 * if <code>baseName</code>, <code>targetLocale</code>,
1107 * <code>loader</code>, or <code>control</code> is
1109 * @exception MissingResourceException
1110 * if no resource bundle for the specified base name can be found
1111 * @exception IllegalArgumentException
1112 * if the given <code>control</code> doesn't perform properly
1113 * (e.g., <code>control.getCandidateLocales</code> returns null.)
1114 * Note that validation of <code>control</code> is performed as
1118 public static ResourceBundle getBundle(String baseName, Locale targetLocale,
1119 ClassLoader loader, Control control) {
1120 if (loader == null || control == null) {
1121 throw new NullPointerException();
1123 return getBundleImpl(baseName, targetLocale, control);
1126 private static ResourceBundle getBundleImpl(String baseName, Locale locale,
1128 if (locale == null || control == null) {
1129 throw new NullPointerException();
1132 // We create a CacheKey here for use by this call. The base
1133 // name and loader will never change during the bundle loading
1134 // process. We have to make sure that the locale is set before
1135 // using it as a cache key.
1136 CacheKey cacheKey = new CacheKey(baseName, locale);
1137 ResourceBundle bundle = null;
1139 // Quick lookup of the cache.
1140 BundleReference bundleRef = cacheList.get(cacheKey);
1141 if (bundleRef != null) {
1142 bundle = bundleRef.get();
1146 // If this bundle and all of its parents are valid (not expired),
1147 // then return this bundle. If any of the bundles is expired, we
1148 // don't call control.needsReload here but instead drop into the
1149 // complete loading process below.
1150 if (isValidBundle(bundle) && hasValidParentChain(bundle)) {
1154 // No valid bundle was found in the cache, so we need to load the
1155 // resource bundle and its parents.
1157 boolean isKnownControl = (control == Control.INSTANCE) ||
1158 (control instanceof SingleFormatControl);
1159 List<String> formats = control.getFormats(baseName);
1160 if (!isKnownControl && !checkList(formats)) {
1161 throw new IllegalArgumentException("Invalid Control: getFormats");
1164 ResourceBundle baseBundle = null;
1165 for (Locale targetLocale = locale;
1166 targetLocale != null;
1167 targetLocale = control.getFallbackLocale(baseName, targetLocale)) {
1168 List<Locale> candidateLocales = control.getCandidateLocales(baseName, targetLocale);
1169 if (!isKnownControl && !checkList(candidateLocales)) {
1170 throw new IllegalArgumentException("Invalid Control: getCandidateLocales");
1173 bundle = findBundle(cacheKey, candidateLocales, formats, 0, control, baseBundle);
1175 // If the loaded bundle is the base bundle and exactly for the
1176 // requested locale or the only candidate locale, then take the
1177 // bundle as the resulting one. If the loaded bundle is the base
1178 // bundle, it's put on hold until we finish processing all
1179 // fallback locales.
1180 if (isValidBundle(bundle)) {
1181 boolean isBaseBundle = Locale.ROOT.equals(bundle.locale);
1182 if (!isBaseBundle || bundle.locale.equals(locale)
1183 || (candidateLocales.size() == 1
1184 && bundle.locale.equals(candidateLocales.get(0)))) {
1188 // If the base bundle has been loaded, keep the reference in
1189 // baseBundle so that we can avoid any redundant loading in case
1190 // the control specify not to cache bundles.
1191 if (isBaseBundle && baseBundle == null) {
1192 baseBundle = bundle;
1197 if (bundle == null) {
1198 if (baseBundle == null) {
1199 throwMissingResourceException(baseName, locale, cacheKey.getCause());
1201 bundle = baseBundle;
1208 * Checks if the given <code>List</code> is not null, not empty,
1209 * not having null in its elements.
1211 private static final boolean checkList(List a) {
1212 boolean valid = (a != null && a.size() != 0);
1214 int size = a.size();
1215 for (int i = 0; valid && i < size; i++) {
1216 valid = (a.get(i) != null);
1222 private static final ResourceBundle findBundle(CacheKey cacheKey,
1223 List<Locale> candidateLocales,
1224 List<String> formats,
1227 ResourceBundle baseBundle) {
1228 Locale targetLocale = candidateLocales.get(index);
1229 ResourceBundle parent = null;
1230 if (index != candidateLocales.size() - 1) {
1231 parent = findBundle(cacheKey, candidateLocales, formats, index + 1,
1232 control, baseBundle);
1233 } else if (baseBundle != null && Locale.ROOT.equals(targetLocale)) {
1237 // Before we do the real loading work, see whether we need to
1238 // do some housekeeping: If references to class loaders or
1239 // resource bundles have been nulled out, remove all related
1240 // information from the cache.
1242 while ((ref = referenceQueue.poll()) != null) {
1243 cacheList.remove(((CacheKeyReference)ref).getCacheKey());
1246 // flag indicating the resource bundle has expired in the cache
1247 boolean expiredBundle = false;
1249 // First, look up the cache to see if it's in the cache, without
1250 // attempting to load bundle.
1251 cacheKey.setLocale(targetLocale);
1252 ResourceBundle bundle = findBundleInCache(cacheKey, control);
1253 if (isValidBundle(bundle)) {
1254 expiredBundle = bundle.expired;
1255 if (!expiredBundle) {
1256 // If its parent is the one asked for by the candidate
1257 // locales (the runtime lookup path), we can take the cached
1258 // one. (If it's not identical, then we'd have to check the
1259 // parent's parents to be consistent with what's been
1261 if (bundle.parent == parent) {
1264 // Otherwise, remove the cached one since we can't keep
1265 // the same bundles having different parents.
1266 BundleReference bundleRef = cacheList.get(cacheKey);
1267 if (bundleRef != null && bundleRef.get() == bundle) {
1268 cacheList.remove(cacheKey);
1273 if (bundle != NONEXISTENT_BUNDLE) {
1274 CacheKey constKey = (CacheKey) cacheKey.clone();
1277 bundle = loadBundle(cacheKey, formats, control, expiredBundle);
1278 if (bundle != null) {
1279 if (bundle.parent == null) {
1280 bundle.setParent(parent);
1282 bundle.locale = targetLocale;
1283 bundle = putBundleInCache(cacheKey, bundle, control);
1287 // Put NONEXISTENT_BUNDLE in the cache as a mark that there's no bundle
1288 // instance for the locale.
1289 putBundleInCache(cacheKey, NONEXISTENT_BUNDLE, control);
1291 if (constKey.getCause() instanceof InterruptedException) {
1292 Thread.currentThread().interrupt();
1299 private static final ResourceBundle loadBundle(CacheKey cacheKey,
1300 List<String> formats,
1304 // Here we actually load the bundle in the order of formats
1305 // specified by the getFormats() value.
1306 Locale targetLocale = cacheKey.getLocale();
1308 ResourceBundle bundle = null;
1309 int size = formats.size();
1310 for (int i = 0; i < size; i++) {
1311 String format = formats.get(i);
1313 bundle = control.newBundle(cacheKey.getName(), targetLocale, format,
1315 } catch (LinkageError error) {
1316 // We need to handle the LinkageError case due to
1317 // inconsistent case-sensitivity in ClassLoader.
1318 // See 6572242 for details.
1319 cacheKey.setCause(error);
1320 } catch (Exception cause) {
1321 cacheKey.setCause(cause);
1323 if (bundle != null) {
1324 // Set the format in the cache key so that it can be
1325 // used when calling needsReload later.
1326 cacheKey.setFormat(format);
1327 bundle.name = cacheKey.getName();
1328 bundle.locale = targetLocale;
1329 // Bundle provider might reuse instances. So we should make
1330 // sure to clear the expired flag here.
1331 bundle.expired = false;
1339 private static final boolean isValidBundle(ResourceBundle bundle) {
1340 return bundle != null && bundle != NONEXISTENT_BUNDLE;
1344 * Determines whether any of resource bundles in the parent chain,
1345 * including the leaf, have expired.
1347 private static final boolean hasValidParentChain(ResourceBundle bundle) {
1348 long now = System.currentTimeMillis();
1349 while (bundle != null) {
1350 if (bundle.expired) {
1353 CacheKey key = bundle.cacheKey;
1355 long expirationTime = key.expirationTime;
1356 if (expirationTime >= 0 && expirationTime <= now) {
1360 bundle = bundle.parent;
1366 * Throw a MissingResourceException with proper message
1368 private static final void throwMissingResourceException(String baseName,
1371 // If the cause is a MissingResourceException, avoid creating
1372 // a long chain. (6355009)
1373 if (cause instanceof MissingResourceException) {
1376 throw new MissingResourceException("Can't find bundle for base name "
1377 + baseName + ", locale " + locale,
1378 baseName + "_" + locale, // className
1384 * Finds a bundle in the cache. Any expired bundles are marked as
1385 * `expired' and removed from the cache upon return.
1387 * @param cacheKey the key to look up the cache
1388 * @param control the Control to be used for the expiration control
1389 * @return the cached bundle, or null if the bundle is not found in the
1390 * cache or its parent has expired. <code>bundle.expire</code> is true
1391 * upon return if the bundle in the cache has expired.
1393 private static final ResourceBundle findBundleInCache(CacheKey cacheKey,
1395 BundleReference bundleRef = cacheList.get(cacheKey);
1396 if (bundleRef == null) {
1399 ResourceBundle bundle = bundleRef.get();
1400 if (bundle == null) {
1403 ResourceBundle p = bundle.parent;
1404 assert p != NONEXISTENT_BUNDLE;
1405 // If the parent has expired, then this one must also expire. We
1406 // check only the immediate parent because the actual loading is
1407 // done from the root (base) to leaf (child) and the purpose of
1408 // checking is to propagate expiration towards the leaf. For
1409 // example, if the requested locale is ja_JP_JP and there are
1410 // bundles for all of the candidates in the cache, we have a list,
1412 // base <- ja <- ja_JP <- ja_JP_JP
1414 // If ja has expired, then it will reload ja and the list becomes a
1418 // " <- ja (expired) <- ja_JP <- ja_JP_JP
1420 // When looking up ja_JP in the cache, it finds ja_JP in the cache
1421 // which references to the expired ja. Then, ja_JP is marked as
1422 // expired and removed from the cache. This will be propagated to
1425 // Now, it's possible, for example, that while loading new ja_JP,
1426 // someone else has started loading the same bundle and finds the
1427 // base bundle has expired. Then, what we get from the first
1428 // getBundle call includes the expired base bundle. However, if
1429 // someone else didn't start its loading, we wouldn't know if the
1430 // base bundle has expired at the end of the loading process. The
1431 // expiration control doesn't guarantee that the returned bundle and
1432 // its parents haven't expired.
1434 // We could check the entire parent chain to see if there's any in
1435 // the chain that has expired. But this process may never end. An
1436 // extreme case would be that getTimeToLive returns 0 and
1437 // needsReload always returns true.
1438 if (p != null && p.expired) {
1439 assert bundle != NONEXISTENT_BUNDLE;
1440 bundle.expired = true;
1441 bundle.cacheKey = null;
1442 cacheList.remove(cacheKey);
1445 CacheKey key = bundleRef.getCacheKey();
1446 long expirationTime = key.expirationTime;
1447 if (!bundle.expired && expirationTime >= 0 &&
1448 expirationTime <= System.currentTimeMillis()) {
1449 // its TTL period has expired.
1450 if (bundle != NONEXISTENT_BUNDLE) {
1451 // Synchronize here to call needsReload to avoid
1452 // redundant concurrent calls for the same bundle.
1453 synchronized (bundle) {
1454 expirationTime = key.expirationTime;
1455 if (!bundle.expired && expirationTime >= 0 &&
1456 expirationTime <= System.currentTimeMillis()) {
1458 bundle.expired = control.needsReload(key.getName(),
1464 } catch (Exception e) {
1465 cacheKey.setCause(e);
1467 if (bundle.expired) {
1468 // If the bundle needs to be reloaded, then
1469 // remove the bundle from the cache, but
1470 // return the bundle with the expired flag
1472 bundle.cacheKey = null;
1473 cacheList.remove(cacheKey);
1475 // Update the expiration control info. and reuse
1476 // the same bundle instance
1477 setExpirationTime(key, control);
1482 // We just remove NONEXISTENT_BUNDLE from the cache.
1483 cacheList.remove(cacheKey);
1492 * Put a new bundle in the cache.
1494 * @param cacheKey the key for the resource bundle
1495 * @param bundle the resource bundle to be put in the cache
1496 * @return the ResourceBundle for the cacheKey; if someone has put
1497 * the bundle before this call, the one found in the cache is
1500 private static final ResourceBundle putBundleInCache(CacheKey cacheKey,
1501 ResourceBundle bundle,
1503 setExpirationTime(cacheKey, control);
1504 if (cacheKey.expirationTime != Control.TTL_DONT_CACHE) {
1505 CacheKey key = (CacheKey) cacheKey.clone();
1506 BundleReference bundleRef = new BundleReference(bundle, referenceQueue, key);
1507 bundle.cacheKey = key;
1509 // Put the bundle in the cache if it's not been in the cache.
1510 BundleReference result = cacheList.put(key, bundleRef);
1512 // If someone else has put the same bundle in the cache before
1513 // us and it has not expired, we should use the one in the cache.
1514 if (result != null) {
1515 ResourceBundle rb = result.get();
1516 if (rb != null && !rb.expired) {
1517 // Clear the back link to the cache key
1518 bundle.cacheKey = null;
1520 // Clear the reference in the BundleReference so that
1521 // it won't be enqueued.
1524 // Replace the invalid (garbage collected or expired)
1525 // instance with the valid one.
1526 cacheList.put(key, bundleRef);
1533 private static final void setExpirationTime(CacheKey cacheKey, Control control) {
1534 long ttl = control.getTimeToLive(cacheKey.getName(),
1535 cacheKey.getLocale());
1537 // If any expiration time is specified, set the time to be
1538 // expired in the cache.
1539 long now = System.currentTimeMillis();
1540 cacheKey.loadTime = now;
1541 cacheKey.expirationTime = now + ttl;
1542 } else if (ttl >= Control.TTL_NO_EXPIRATION_CONTROL) {
1543 cacheKey.expirationTime = ttl;
1545 throw new IllegalArgumentException("Invalid Control: TTL=" + ttl);
1550 * Removes all resource bundles from the cache that have been loaded
1551 * using the caller's class loader.
1554 * @see ResourceBundle.Control#getTimeToLive(String,Locale)
1556 public static final void clearCache() {
1561 * Removes all resource bundles from the cache that have been loaded
1562 * using the given class loader.
1564 * @param loader the class loader
1565 * @exception NullPointerException if <code>loader</code> is null
1567 * @see ResourceBundle.Control#getTimeToLive(String,Locale)
1569 public static final void clearCache(ClassLoader loader) {
1570 if (loader == null) {
1571 throw new NullPointerException();
1573 Set<CacheKey> set = cacheList.keySet();
1574 for (CacheKey key : set) {
1580 * Gets an object for the given key from this resource bundle.
1581 * Returns null if this resource bundle does not contain an
1582 * object for the given key.
1584 * @param key the key for the desired object
1585 * @exception NullPointerException if <code>key</code> is <code>null</code>
1586 * @return the object for the given key, or null
1588 protected abstract Object handleGetObject(String key);
1591 * Returns an enumeration of the keys.
1593 * @return an <code>Enumeration</code> of the keys contained in
1594 * this <code>ResourceBundle</code> and its parent bundles.
1596 public abstract Enumeration<String> getKeys();
1599 * Determines whether the given <code>key</code> is contained in
1600 * this <code>ResourceBundle</code> or its parent bundles.
1603 * the resource <code>key</code>
1604 * @return <code>true</code> if the given <code>key</code> is
1605 * contained in this <code>ResourceBundle</code> or its
1606 * parent bundles; <code>false</code> otherwise.
1607 * @exception NullPointerException
1608 * if <code>key</code> is <code>null</code>
1611 public boolean containsKey(String key) {
1613 throw new NullPointerException();
1615 for (ResourceBundle rb = this; rb != null; rb = rb.parent) {
1616 if (rb.handleKeySet().contains(key)) {
1624 * Returns a <code>Set</code> of all keys contained in this
1625 * <code>ResourceBundle</code> and its parent bundles.
1627 * @return a <code>Set</code> of all keys contained in this
1628 * <code>ResourceBundle</code> and its parent bundles.
1631 public Set<String> keySet() {
1632 Set<String> keys = new HashSet<>();
1633 for (ResourceBundle rb = this; rb != null; rb = rb.parent) {
1634 keys.addAll(rb.handleKeySet());
1640 * Returns a <code>Set</code> of the keys contained <em>only</em>
1641 * in this <code>ResourceBundle</code>.
1643 * <p>The default implementation returns a <code>Set</code> of the
1644 * keys returned by the {@link #getKeys() getKeys} method except
1645 * for the ones for which the {@link #handleGetObject(String)
1646 * handleGetObject} method returns <code>null</code>. Once the
1647 * <code>Set</code> has been created, the value is kept in this
1648 * <code>ResourceBundle</code> in order to avoid producing the
1649 * same <code>Set</code> in subsequent calls. Subclasses can
1650 * override this method for faster handling.
1652 * @return a <code>Set</code> of the keys contained only in this
1653 * <code>ResourceBundle</code>
1656 protected Set<String> handleKeySet() {
1657 if (keySet == null) {
1658 synchronized (this) {
1659 if (keySet == null) {
1660 Set<String> keys = new HashSet<>();
1661 Enumeration<String> enumKeys = getKeys();
1662 while (enumKeys.hasMoreElements()) {
1663 String key = enumKeys.nextElement();
1664 if (handleGetObject(key) != null) {
1678 * <code>ResourceBundle.Control</code> defines a set of callback methods
1679 * that are invoked by the {@link ResourceBundle#getBundle(String,
1680 * Locale, ClassLoader, Control) ResourceBundle.getBundle} factory
1681 * methods during the bundle loading process. In other words, a
1682 * <code>ResourceBundle.Control</code> collaborates with the factory
1683 * methods for loading resource bundles. The default implementation of
1684 * the callback methods provides the information necessary for the
1685 * factory methods to perform the <a
1686 * href="./ResourceBundle.html#default_behavior">default behavior</a>.
1688 * <p>In addition to the callback methods, the {@link
1689 * #toBundleName(String, Locale) toBundleName} and {@link
1690 * #toResourceName(String, String) toResourceName} methods are defined
1691 * primarily for convenience in implementing the callback
1692 * methods. However, the <code>toBundleName</code> method could be
1693 * overridden to provide different conventions in the organization and
1694 * packaging of localized resources. The <code>toResourceName</code>
1695 * method is <code>final</code> to avoid use of wrong resource and class
1698 * <p>Two factory methods, {@link #getControl(List)} and {@link
1699 * #getNoFallbackControl(List)}, provide
1700 * <code>ResourceBundle.Control</code> instances that implement common
1701 * variations of the default bundle loading process.
1703 * <p>The formats returned by the {@link Control#getFormats(String)
1704 * getFormats} method and candidate locales returned by the {@link
1705 * ResourceBundle.Control#getCandidateLocales(String, Locale)
1706 * getCandidateLocales} method must be consistent in all
1707 * <code>ResourceBundle.getBundle</code> invocations for the same base
1708 * bundle. Otherwise, the <code>ResourceBundle.getBundle</code> methods
1709 * may return unintended bundles. For example, if only
1710 * <code>"java.class"</code> is returned by the <code>getFormats</code>
1711 * method for the first call to <code>ResourceBundle.getBundle</code>
1712 * and only <code>"java.properties"</code> for the second call, then the
1713 * second call will return the class-based one that has been cached
1714 * during the first call.
1716 * <p>A <code>ResourceBundle.Control</code> instance must be thread-safe
1717 * if it's simultaneously used by multiple threads.
1718 * <code>ResourceBundle.getBundle</code> does not synchronize to call
1719 * the <code>ResourceBundle.Control</code> methods. The default
1720 * implementations of the methods are thread-safe.
1722 * <p>Applications can specify <code>ResourceBundle.Control</code>
1723 * instances returned by the <code>getControl</code> factory methods or
1724 * created from a subclass of <code>ResourceBundle.Control</code> to
1725 * customize the bundle loading process. The following are examples of
1726 * changing the default bundle loading process.
1728 * <p><b>Example 1</b>
1730 * <p>The following code lets <code>ResourceBundle.getBundle</code> look
1731 * up only properties-based resources.
1734 * import java.util.*;
1735 * import static java.util.ResourceBundle.Control.*;
1737 * ResourceBundle bundle =
1738 * ResourceBundle.getBundle("MyResources", new Locale("fr", "CH"),
1739 * ResourceBundle.Control.getControl(FORMAT_PROPERTIES));
1742 * Given the resource bundles in the <a
1743 * href="./ResourceBundle.html#default_behavior_example">example</a> in
1744 * the <code>ResourceBundle.getBundle</code> description, this
1745 * <code>ResourceBundle.getBundle</code> call loads
1746 * <code>MyResources_fr_CH.properties</code> whose parent is
1747 * <code>MyResources_fr.properties</code> whose parent is
1748 * <code>MyResources.properties</code>. (<code>MyResources_fr_CH.properties</code>
1749 * is not hidden, but <code>MyResources_fr_CH.class</code> is.)
1751 * <p><b>Example 2</b>
1753 * <p>The following is an example of loading XML-based bundles
1754 * using {@link Properties#loadFromXML(java.io.InputStream)
1755 * Properties.loadFromXML}.
1758 * ResourceBundle rb = ResourceBundle.getBundle("Messages",
1759 * new ResourceBundle.Control() {
1760 * public List<String> getFormats(String baseName) {
1761 * if (baseName == null)
1762 * throw new NullPointerException();
1763 * return Arrays.asList("xml");
1765 * public ResourceBundle newBundle(String baseName,
1768 * ClassLoader loader,
1770 * throws IllegalAccessException,
1771 * InstantiationException,
1773 * if (baseName == null || locale == null
1774 * || format == null || loader == null)
1775 * throw new NullPointerException();
1776 * ResourceBundle bundle = null;
1777 * if (format.equals("xml")) {
1778 * String bundleName = toBundleName(baseName, locale);
1779 * String resourceName = toResourceName(bundleName, format);
1780 * InputStream stream = null;
1782 * URL url = loader.getResource(resourceName);
1783 * if (url != null) {
1784 * URLConnection connection = url.openConnection();
1785 * if (connection != null) {
1786 * // Disable caches to get fresh data for
1788 * connection.setUseCaches(false);
1789 * stream = connection.getInputStream();
1793 * stream = loader.getResourceAsStream(resourceName);
1795 * if (stream != null) {
1796 * BufferedInputStream bis = new BufferedInputStream(stream);
1797 * bundle = new XMLResourceBundle(bis);
1807 * private static class XMLResourceBundle extends ResourceBundle {
1808 * private Properties props;
1809 * XMLResourceBundle(InputStream stream) throws IOException {
1810 * props = new Properties();
1811 * props.loadFromXML(stream);
1813 * protected Object handleGetObject(String key) {
1814 * return props.getProperty(key);
1816 * public Enumeration<String> getKeys() {
1824 public static class Control {
1826 * The default format <code>List</code>, which contains the strings
1827 * <code>"java.class"</code> and <code>"java.properties"</code>, in
1828 * this order. This <code>List</code> is {@linkplain
1829 * Collections#unmodifiableList(List) unmodifiable}.
1831 * @see #getFormats(String)
1833 public static final List<String> FORMAT_DEFAULT
1834 = Collections.unmodifiableList(Arrays.asList("java.class",
1835 "java.properties"));
1838 * The class-only format <code>List</code> containing
1839 * <code>"java.class"</code>. This <code>List</code> is {@linkplain
1840 * Collections#unmodifiableList(List) unmodifiable}.
1842 * @see #getFormats(String)
1844 public static final List<String> FORMAT_CLASS
1845 = Collections.unmodifiableList(Arrays.asList("java.class"));
1848 * The properties-only format <code>List</code> containing
1849 * <code>"java.properties"</code>. This <code>List</code> is
1850 * {@linkplain Collections#unmodifiableList(List) unmodifiable}.
1852 * @see #getFormats(String)
1854 public static final List<String> FORMAT_PROPERTIES
1855 = Collections.unmodifiableList(Arrays.asList("java.properties"));
1858 * The time-to-live constant for not caching loaded resource bundle
1861 * @see #getTimeToLive(String, Locale)
1863 public static final long TTL_DONT_CACHE = -1;
1866 * The time-to-live constant for disabling the expiration control
1867 * for loaded resource bundle instances in the cache.
1869 * @see #getTimeToLive(String, Locale)
1871 public static final long TTL_NO_EXPIRATION_CONTROL = -2;
1873 private static final Control INSTANCE = new Control();
1876 * Sole constructor. (For invocation by subclass constructors,
1877 * typically implicit.)
1879 protected Control() {
1883 * Returns a <code>ResourceBundle.Control</code> in which the {@link
1884 * #getFormats(String) getFormats} method returns the specified
1885 * <code>formats</code>. The <code>formats</code> must be equal to
1886 * one of {@link Control#FORMAT_PROPERTIES}, {@link
1887 * Control#FORMAT_CLASS} or {@link
1888 * Control#FORMAT_DEFAULT}. <code>ResourceBundle.Control</code>
1889 * instances returned by this method are singletons and thread-safe.
1891 * <p>Specifying {@link Control#FORMAT_DEFAULT} is equivalent to
1892 * instantiating the <code>ResourceBundle.Control</code> class,
1893 * except that this method returns a singleton.
1896 * the formats to be returned by the
1897 * <code>ResourceBundle.Control.getFormats</code> method
1898 * @return a <code>ResourceBundle.Control</code> supporting the
1899 * specified <code>formats</code>
1900 * @exception NullPointerException
1901 * if <code>formats</code> is <code>null</code>
1902 * @exception IllegalArgumentException
1903 * if <code>formats</code> is unknown
1905 public static final Control getControl(List<String> formats) {
1906 if (formats.equals(Control.FORMAT_PROPERTIES)) {
1907 return SingleFormatControl.PROPERTIES_ONLY;
1909 if (formats.equals(Control.FORMAT_CLASS)) {
1910 return SingleFormatControl.CLASS_ONLY;
1912 if (formats.equals(Control.FORMAT_DEFAULT)) {
1913 return Control.INSTANCE;
1915 throw new IllegalArgumentException();
1919 * Returns a <code>ResourceBundle.Control</code> in which the {@link
1920 * #getFormats(String) getFormats} method returns the specified
1921 * <code>formats</code> and the {@link
1922 * Control#getFallbackLocale(String, Locale) getFallbackLocale}
1923 * method returns <code>null</code>. The <code>formats</code> must
1924 * be equal to one of {@link Control#FORMAT_PROPERTIES}, {@link
1925 * Control#FORMAT_CLASS} or {@link Control#FORMAT_DEFAULT}.
1926 * <code>ResourceBundle.Control</code> instances returned by this
1927 * method are singletons and thread-safe.
1930 * the formats to be returned by the
1931 * <code>ResourceBundle.Control.getFormats</code> method
1932 * @return a <code>ResourceBundle.Control</code> supporting the
1933 * specified <code>formats</code> with no fallback
1934 * <code>Locale</code> support
1935 * @exception NullPointerException
1936 * if <code>formats</code> is <code>null</code>
1937 * @exception IllegalArgumentException
1938 * if <code>formats</code> is unknown
1940 public static final Control getNoFallbackControl(List<String> formats) {
1941 if (formats.equals(Control.FORMAT_DEFAULT)) {
1942 return NoFallbackControl.NO_FALLBACK;
1944 if (formats.equals(Control.FORMAT_PROPERTIES)) {
1945 return NoFallbackControl.PROPERTIES_ONLY_NO_FALLBACK;
1947 if (formats.equals(Control.FORMAT_CLASS)) {
1948 return NoFallbackControl.CLASS_ONLY_NO_FALLBACK;
1950 throw new IllegalArgumentException();
1954 * Returns a <code>List</code> of <code>String</code>s containing
1955 * formats to be used to load resource bundles for the given
1956 * <code>baseName</code>. The <code>ResourceBundle.getBundle</code>
1957 * factory method tries to load resource bundles with formats in the
1958 * order specified by the list. The list returned by this method
1959 * must have at least one <code>String</code>. The predefined
1960 * formats are <code>"java.class"</code> for class-based resource
1961 * bundles and <code>"java.properties"</code> for {@linkplain
1962 * PropertyResourceBundle properties-based} ones. Strings starting
1963 * with <code>"java."</code> are reserved for future extensions and
1964 * must not be used by application-defined formats.
1966 * <p>It is not a requirement to return an immutable (unmodifiable)
1967 * <code>List</code>. However, the returned <code>List</code> must
1968 * not be mutated after it has been returned by
1969 * <code>getFormats</code>.
1971 * <p>The default implementation returns {@link #FORMAT_DEFAULT} so
1972 * that the <code>ResourceBundle.getBundle</code> factory method
1973 * looks up first class-based resource bundles, then
1974 * properties-based ones.
1977 * the base name of the resource bundle, a fully qualified class
1979 * @return a <code>List</code> of <code>String</code>s containing
1980 * formats for loading resource bundles.
1981 * @exception NullPointerException
1982 * if <code>baseName</code> is null
1983 * @see #FORMAT_DEFAULT
1984 * @see #FORMAT_CLASS
1985 * @see #FORMAT_PROPERTIES
1987 public List<String> getFormats(String baseName) {
1988 if (baseName == null) {
1989 throw new NullPointerException();
1991 return FORMAT_DEFAULT;
1995 * Returns a <code>List</code> of <code>Locale</code>s as candidate
1996 * locales for <code>baseName</code> and <code>locale</code>. This
1997 * method is called by the <code>ResourceBundle.getBundle</code>
1998 * factory method each time the factory method tries finding a
1999 * resource bundle for a target <code>Locale</code>.
2001 * <p>The sequence of the candidate locales also corresponds to the
2002 * runtime resource lookup path (also known as the <I>parent
2003 * chain</I>), if the corresponding resource bundles for the
2004 * candidate locales exist and their parents are not defined by
2005 * loaded resource bundles themselves. The last element of the list
2006 * must be a {@linkplain Locale#ROOT root locale} if it is desired to
2007 * have the base bundle as the terminal of the parent chain.
2009 * <p>If the given locale is equal to <code>Locale.ROOT</code> (the
2010 * root locale), a <code>List</code> containing only the root
2011 * <code>Locale</code> must be returned. In this case, the
2012 * <code>ResourceBundle.getBundle</code> factory method loads only
2013 * the base bundle as the resulting resource bundle.
2015 * <p>It is not a requirement to return an immutable (unmodifiable)
2016 * <code>List</code>. However, the returned <code>List</code> must not
2017 * be mutated after it has been returned by
2018 * <code>getCandidateLocales</code>.
2020 * <p>The default implementation returns a <code>List</code> containing
2021 * <code>Locale</code>s using the rules described below. In the
2022 * description below, <em>L</em>, <em>S</em>, <em>C</em> and <em>V</em>
2023 * respectively represent non-empty language, script, country, and
2024 * variant. For example, [<em>L</em>, <em>C</em>] represents a
2025 * <code>Locale</code> that has non-empty values only for language and
2026 * country. The form <em>L</em>("xx") represents the (non-empty)
2027 * language value is "xx". For all cases, <code>Locale</code>s whose
2028 * final component values are empty strings are omitted.
2030 * <ol><li>For an input <code>Locale</code> with an empty script value,
2031 * append candidate <code>Locale</code>s by omitting the final component
2032 * one by one as below:
2035 * <li> [<em>L</em>, <em>C</em>, <em>V</em>]
2036 * <li> [<em>L</em>, <em>C</em>]
2038 * <li> <code>Locale.ROOT</code>
2041 * <li>For an input <code>Locale</code> with a non-empty script value,
2042 * append candidate <code>Locale</code>s by omitting the final component
2043 * up to language, then append candidates generated from the
2044 * <code>Locale</code> with country and variant restored:
2047 * <li> [<em>L</em>, <em>S</em>, <em>C</em>, <em>V</em>]
2048 * <li> [<em>L</em>, <em>S</em>, <em>C</em>]
2049 * <li> [<em>L</em>, <em>S</em>]
2050 * <li> [<em>L</em>, <em>C</em>, <em>V</em>]
2051 * <li> [<em>L</em>, <em>C</em>]
2053 * <li> <code>Locale.ROOT</code>
2056 * <li>For an input <code>Locale</code> with a variant value consisting
2057 * of multiple subtags separated by underscore, generate candidate
2058 * <code>Locale</code>s by omitting the variant subtags one by one, then
2059 * insert them after every occurence of <code> Locale</code>s with the
2060 * full variant value in the original list. For example, if the
2061 * the variant consists of two subtags <em>V1</em> and <em>V2</em>:
2064 * <li> [<em>L</em>, <em>S</em>, <em>C</em>, <em>V1</em>, <em>V2</em>]
2065 * <li> [<em>L</em>, <em>S</em>, <em>C</em>, <em>V1</em>]
2066 * <li> [<em>L</em>, <em>S</em>, <em>C</em>]
2067 * <li> [<em>L</em>, <em>S</em>]
2068 * <li> [<em>L</em>, <em>C</em>, <em>V1</em>, <em>V2</em>]
2069 * <li> [<em>L</em>, <em>C</em>, <em>V1</em>]
2070 * <li> [<em>L</em>, <em>C</em>]
2072 * <li> <code>Locale.ROOT</code>
2075 * <li>Special cases for Chinese. When an input <code>Locale</code> has the
2076 * language "zh" (Chinese) and an empty script value, either "Hans" (Simplified) or
2077 * "Hant" (Traditional) might be supplied, depending on the country.
2078 * When the country is "CN" (China) or "SG" (Singapore), "Hans" is supplied.
2079 * When the country is "HK" (Hong Kong SAR China), "MO" (Macau SAR China),
2080 * or "TW" (Taiwan), "Hant" is supplied. For all other countries or when the country
2081 * is empty, no script is supplied. For example, for <code>Locale("zh", "CN")
2082 * </code>, the candidate list will be:
2084 * <li> [<em>L</em>("zh"), <em>S</em>("Hans"), <em>C</em>("CN")]
2085 * <li> [<em>L</em>("zh"), <em>S</em>("Hans")]
2086 * <li> [<em>L</em>("zh"), <em>C</em>("CN")]
2087 * <li> [<em>L</em>("zh")]
2088 * <li> <code>Locale.ROOT</code>
2091 * For <code>Locale("zh", "TW")</code>, the candidate list will be:
2093 * <li> [<em>L</em>("zh"), <em>S</em>("Hant"), <em>C</em>("TW")]
2094 * <li> [<em>L</em>("zh"), <em>S</em>("Hant")]
2095 * <li> [<em>L</em>("zh"), <em>C</em>("TW")]
2096 * <li> [<em>L</em>("zh")]
2097 * <li> <code>Locale.ROOT</code>
2100 * <li>Special cases for Norwegian. Both <code>Locale("no", "NO",
2101 * "NY")</code> and <code>Locale("nn", "NO")</code> represent Norwegian
2102 * Nynorsk. When a locale's language is "nn", the standard candidate
2103 * list is generated up to [<em>L</em>("nn")], and then the following
2104 * candidates are added:
2106 * <ul><li> [<em>L</em>("no"), <em>C</em>("NO"), <em>V</em>("NY")]
2107 * <li> [<em>L</em>("no"), <em>C</em>("NO")]
2108 * <li> [<em>L</em>("no")]
2109 * <li> <code>Locale.ROOT</code>
2112 * If the locale is exactly <code>Locale("no", "NO", "NY")</code>, it is first
2113 * converted to <code>Locale("nn", "NO")</code> and then the above procedure is
2116 * <p>Also, Java treats the language "no" as a synonym of Norwegian
2117 * Bokmål "nb". Except for the single case <code>Locale("no",
2118 * "NO", "NY")</code> (handled above), when an input <code>Locale</code>
2119 * has language "no" or "nb", candidate <code>Locale</code>s with
2120 * language code "no" and "nb" are interleaved, first using the
2121 * requested language, then using its synonym. For example,
2122 * <code>Locale("nb", "NO", "POSIX")</code> generates the following
2126 * <li> [<em>L</em>("nb"), <em>C</em>("NO"), <em>V</em>("POSIX")]
2127 * <li> [<em>L</em>("no"), <em>C</em>("NO"), <em>V</em>("POSIX")]
2128 * <li> [<em>L</em>("nb"), <em>C</em>("NO")]
2129 * <li> [<em>L</em>("no"), <em>C</em>("NO")]
2130 * <li> [<em>L</em>("nb")]
2131 * <li> [<em>L</em>("no")]
2132 * <li> <code>Locale.ROOT</code>
2135 * <code>Locale("no", "NO", "POSIX")</code> would generate the same list
2136 * except that locales with "no" would appear before the corresponding
2137 * locales with "nb".</li>
2142 * <p>The default implementation uses an {@link ArrayList} that
2143 * overriding implementations may modify before returning it to the
2144 * caller. However, a subclass must not modify it after it has
2145 * been returned by <code>getCandidateLocales</code>.
2147 * <p>For example, if the given <code>baseName</code> is "Messages"
2148 * and the given <code>locale</code> is
2149 * <code>Locale("ja", "", "XX")</code>, then a
2150 * <code>List</code> of <code>Locale</code>s:
2152 * Locale("ja", "", "XX")
2156 * is returned. And if the resource bundles for the "ja" and
2157 * "" <code>Locale</code>s are found, then the runtime resource
2158 * lookup path (parent chain) is:
2160 * Messages_ja -> Messages
2164 * the base name of the resource bundle, a fully
2165 * qualified class name
2167 * the locale for which a resource bundle is desired
2168 * @return a <code>List</code> of candidate
2169 * <code>Locale</code>s for the given <code>locale</code>
2170 * @exception NullPointerException
2171 * if <code>baseName</code> or <code>locale</code> is
2174 public List<Locale> getCandidateLocales(String baseName, Locale locale) {
2175 if (baseName == null) {
2176 throw new NullPointerException();
2178 return new ArrayList<>(CANDIDATES_CACHE.get(locale));
2181 private static final CandidateListCache CANDIDATES_CACHE = new CandidateListCache();
2183 private static class CandidateListCache {
2184 private Locale prevQuery;
2185 private List<Locale> prevResult;
2187 public List<Locale> get(Locale l) {
2188 if (prevQuery == l) {
2191 prevResult = createObject(l);
2196 protected List<Locale> createObject(Locale base) {
2197 String language = base.getLanguage();
2198 String script = base.getScript();
2199 String region = base.getRegion();
2200 String variant = base.getVariant();
2202 // Special handling for Norwegian
2203 boolean isNorwegianBokmal = false;
2204 boolean isNorwegianNynorsk = false;
2205 if (language.equals("no")) {
2206 if (region.equals("NO") && variant.equals("NY")) {
2208 isNorwegianNynorsk = true;
2210 isNorwegianBokmal = true;
2213 if (language.equals("nb") || isNorwegianBokmal) {
2214 List<Locale> tmpList = getDefaultList("nb", script, region, variant);
2215 // Insert a locale replacing "nb" with "no" for every list entry
2216 List<Locale> bokmalList = new LinkedList<>();
2217 for (Locale l : tmpList) {
2219 if (l.getLanguage().length() == 0) {
2222 bokmalList.add(Locale.getInstance("no", l.getScript(), l.getCountry(),
2223 l.getVariant(), null));
2226 } else if (language.equals("nn") || isNorwegianNynorsk) {
2227 // Insert no_NO_NY, no_NO, no after nn
2228 List<Locale> nynorskList = getDefaultList("nn", script, region, variant);
2229 int idx = nynorskList.size() - 1;
2230 nynorskList.add(idx++, Locale.getInstance("no", "NO", "NY"));
2231 nynorskList.add(idx++, Locale.getInstance("no", "NO", ""));
2232 nynorskList.add(idx++, Locale.getInstance("no", "", ""));
2235 // Special handling for Chinese
2236 else if (language.equals("zh")) {
2237 if (script.length() == 0 && region.length() > 0) {
2238 // Supply script for users who want to use zh_Hans/zh_Hant
2239 // as bundle names (recommended for Java7+)
2240 if (region.equals("TW") || region.equals("HK") || region.equals("MO")) {
2242 } else if (region.equals("CN") || region.equals("SG")) {
2245 } else if (script.length() > 0 && region.length() == 0) {
2246 // Supply region(country) for users who still package Chinese
2247 // bundles using old convension.
2248 if (script.equals("Hans")) {
2250 } else if (script.equals("Hant")) {
2256 return getDefaultList(language, script, region, variant);
2259 private static List<Locale> getDefaultList(String language, String script, String region, String variant) {
2260 List<String> variants = null;
2262 if (variant.length() > 0) {
2263 variants = new LinkedList<>();
2264 int idx = variant.length();
2266 variants.add(variant.substring(0, idx));
2267 idx = variant.lastIndexOf('_', --idx);
2271 List<Locale> list = new LinkedList<>();
2273 if (variants != null) {
2274 for (String v : variants) {
2275 list.add(Locale.getInstance(language, script, region, v, null));
2278 if (region.length() > 0) {
2279 list.add(Locale.getInstance(language, script, region, "", null));
2281 if (script.length() > 0) {
2282 list.add(Locale.getInstance(language, script, "", "", null));
2284 // With script, after truncating variant, region and script,
2285 // start over without script.
2286 if (variants != null) {
2287 for (String v : variants) {
2288 list.add(Locale.getInstance(language, "", region, v, null));
2291 if (region.length() > 0) {
2292 list.add(Locale.getInstance(language, "", region, "", null));
2295 if (language.length() > 0) {
2296 list.add(Locale.getInstance(language, "", "", "", null));
2298 // Add root locale at the end
2299 list.add(Locale.ROOT);
2306 * Returns a <code>Locale</code> to be used as a fallback locale for
2307 * further resource bundle searches by the
2308 * <code>ResourceBundle.getBundle</code> factory method. This method
2309 * is called from the factory method every time when no resulting
2310 * resource bundle has been found for <code>baseName</code> and
2311 * <code>locale</code>, where locale is either the parameter for
2312 * <code>ResourceBundle.getBundle</code> or the previous fallback
2313 * locale returned by this method.
2315 * <p>The method returns <code>null</code> if no further fallback
2316 * search is desired.
2318 * <p>The default implementation returns the {@linkplain
2319 * Locale#getDefault() default <code>Locale</code>} if the given
2320 * <code>locale</code> isn't the default one. Otherwise,
2321 * <code>null</code> is returned.
2324 * the base name of the resource bundle, a fully
2325 * qualified class name for which
2326 * <code>ResourceBundle.getBundle</code> has been
2327 * unable to find any resource bundles (except for the
2330 * the <code>Locale</code> for which
2331 * <code>ResourceBundle.getBundle</code> has been
2332 * unable to find any resource bundles (except for the
2334 * @return a <code>Locale</code> for the fallback search,
2335 * or <code>null</code> if no further fallback search
2337 * @exception NullPointerException
2338 * if <code>baseName</code> or <code>locale</code>
2339 * is <code>null</code>
2341 public Locale getFallbackLocale(String baseName, Locale locale) {
2342 if (baseName == null) {
2343 throw new NullPointerException();
2345 Locale defaultLocale = Locale.getDefault();
2346 return locale.equals(defaultLocale) ? null : defaultLocale;
2350 * Instantiates a resource bundle for the given bundle name of the
2351 * given format and locale, using the given class loader if
2352 * necessary. This method returns <code>null</code> if there is no
2353 * resource bundle available for the given parameters. If a resource
2354 * bundle can't be instantiated due to an unexpected error, the
2355 * error must be reported by throwing an <code>Error</code> or
2356 * <code>Exception</code> rather than simply returning
2357 * <code>null</code>.
2359 * <p>If the <code>reload</code> flag is <code>true</code>, it
2360 * indicates that this method is being called because the previously
2361 * loaded resource bundle has expired.
2363 * <p>The default implementation instantiates a
2364 * <code>ResourceBundle</code> as follows.
2368 * <li>The bundle name is obtained by calling {@link
2369 * #toBundleName(String, Locale) toBundleName(baseName,
2372 * <li>If <code>format</code> is <code>"java.class"</code>, the
2373 * {@link Class} specified by the bundle name is loaded by calling
2374 * {@link ClassLoader#loadClass(String)}. Then, a
2375 * <code>ResourceBundle</code> is instantiated by calling {@link
2376 * Class#newInstance()}. Note that the <code>reload</code> flag is
2377 * ignored for loading class-based resource bundles in this default
2378 * implementation.</li>
2380 * <li>If <code>format</code> is <code>"java.properties"</code>,
2381 * {@link #toResourceName(String, String) toResourceName(bundlename,
2382 * "properties")} is called to get the resource name.
2383 * If <code>reload</code> is <code>true</code>, {@link
2384 * ClassLoader#getResource(String) load.getResource} is called
2385 * to get a {@link URL} for creating a {@link
2386 * URLConnection}. This <code>URLConnection</code> is used to
2387 * {@linkplain URLConnection#setUseCaches(boolean) disable the
2388 * caches} of the underlying resource loading layers,
2389 * and to {@linkplain URLConnection#getInputStream() get an
2390 * <code>InputStream</code>}.
2391 * Otherwise, {@link ClassLoader#getResourceAsStream(String)
2392 * loader.getResourceAsStream} is called to get an {@link
2393 * InputStream}. Then, a {@link
2394 * PropertyResourceBundle} is constructed with the
2395 * <code>InputStream</code>.</li>
2397 * <li>If <code>format</code> is neither <code>"java.class"</code>
2398 * nor <code>"java.properties"</code>, an
2399 * <code>IllegalArgumentException</code> is thrown.</li>
2404 * the base bundle name of the resource bundle, a fully
2405 * qualified class name
2407 * the locale for which the resource bundle should be
2410 * the resource bundle format to be loaded
2412 * the <code>ClassLoader</code> to use to load the bundle
2414 * the flag to indicate bundle reloading; <code>true</code>
2415 * if reloading an expired resource bundle,
2416 * <code>false</code> otherwise
2417 * @return the resource bundle instance,
2418 * or <code>null</code> if none could be found.
2419 * @exception NullPointerException
2420 * if <code>bundleName</code>, <code>locale</code>,
2421 * <code>format</code>, or <code>loader</code> is
2422 * <code>null</code>, or if <code>null</code> is returned by
2423 * {@link #toBundleName(String, Locale) toBundleName}
2424 * @exception IllegalArgumentException
2425 * if <code>format</code> is unknown, or if the resource
2426 * found for the given parameters contains malformed data.
2427 * @exception ClassCastException
2428 * if the loaded class cannot be cast to <code>ResourceBundle</code>
2429 * @exception IllegalAccessException
2430 * if the class or its nullary constructor is not
2432 * @exception InstantiationException
2433 * if the instantiation of a class fails for some other
2435 * @exception ExceptionInInitializerError
2436 * if the initialization provoked by this method fails.
2437 * @exception SecurityException
2438 * If a security manager is present and creation of new
2439 * instances is denied. See {@link Class#newInstance()}
2441 * @exception IOException
2442 * if an error occurred when reading resources using
2443 * any I/O operations
2445 public ResourceBundle newBundle(String baseName, Locale locale, String format,
2446 ClassLoader loader, boolean reload)
2447 throws IllegalAccessException, InstantiationException, IOException {
2448 String bundleName = toBundleName(baseName, locale);
2449 ResourceBundle bundle = null;
2450 if (format.equals("java.class")) {
2452 Class<? extends ResourceBundle> bundleClass
2453 = (Class<? extends ResourceBundle>)(loader != null ?
2454 loader.loadClass(bundleName) :
2455 Class.forName(bundleName));
2457 // If the class isn't a ResourceBundle subclass, throw a
2458 // ClassCastException.
2459 if (ResourceBundle.class.isAssignableFrom(bundleClass)) {
2460 bundle = bundleClass.newInstance();
2462 throw new ClassCastException(bundleClass.getName()
2463 + " cannot be cast to ResourceBundle");
2465 } catch (ClassNotFoundException e) {
2467 } else if (format.equals("java.properties")) {
2468 final String resourceName = toResourceName(bundleName, "properties");
2469 final ClassLoader classLoader = loader;
2470 final boolean reloadFlag = reload;
2471 InputStream stream = classLoader != null ? classLoader.getResourceAsStream(resourceName) :
2472 ResourceBundle.class.getResourceAsStream("/" + resourceName);
2473 if (stream != null) {
2475 bundle = new PropertyResourceBundle(stream);
2481 throw new IllegalArgumentException("unknown format: " + format);
2487 * Returns the time-to-live (TTL) value for resource bundles that
2488 * are loaded under this
2489 * <code>ResourceBundle.Control</code>. Positive time-to-live values
2490 * specify the number of milliseconds a bundle can remain in the
2491 * cache without being validated against the source data from which
2492 * it was constructed. The value 0 indicates that a bundle must be
2493 * validated each time it is retrieved from the cache. {@link
2494 * #TTL_DONT_CACHE} specifies that loaded resource bundles are not
2495 * put in the cache. {@link #TTL_NO_EXPIRATION_CONTROL} specifies
2496 * that loaded resource bundles are put in the cache with no
2497 * expiration control.
2499 * <p>The expiration affects only the bundle loading process by the
2500 * <code>ResourceBundle.getBundle</code> factory method. That is,
2501 * if the factory method finds a resource bundle in the cache that
2502 * has expired, the factory method calls the {@link
2503 * #needsReload(String, Locale, String, ClassLoader, ResourceBundle,
2504 * long) needsReload} method to determine whether the resource
2505 * bundle needs to be reloaded. If <code>needsReload</code> returns
2506 * <code>true</code>, the cached resource bundle instance is removed
2507 * from the cache. Otherwise, the instance stays in the cache,
2508 * updated with the new TTL value returned by this method.
2510 * <p>All cached resource bundles are subject to removal from the
2511 * cache due to memory constraints of the runtime environment.
2512 * Returning a large positive value doesn't mean to lock loaded
2513 * resource bundles in the cache.
2515 * <p>The default implementation returns {@link #TTL_NO_EXPIRATION_CONTROL}.
2518 * the base name of the resource bundle for which the
2519 * expiration value is specified.
2521 * the locale of the resource bundle for which the
2522 * expiration value is specified.
2523 * @return the time (0 or a positive millisecond offset from the
2524 * cached time) to get loaded bundles expired in the cache,
2525 * {@link #TTL_NO_EXPIRATION_CONTROL} to disable the
2526 * expiration control, or {@link #TTL_DONT_CACHE} to disable
2528 * @exception NullPointerException
2529 * if <code>baseName</code> or <code>locale</code> is
2532 public long getTimeToLive(String baseName, Locale locale) {
2533 if (baseName == null || locale == null) {
2534 throw new NullPointerException();
2536 return TTL_NO_EXPIRATION_CONTROL;
2540 * Determines if the expired <code>bundle</code> in the cache needs
2541 * to be reloaded based on the loading time given by
2542 * <code>loadTime</code> or some other criteria. The method returns
2543 * <code>true</code> if reloading is required; <code>false</code>
2544 * otherwise. <code>loadTime</code> is a millisecond offset since
2545 * the <a href="Calendar.html#Epoch"> <code>Calendar</code>
2548 * The calling <code>ResourceBundle.getBundle</code> factory method
2549 * calls this method on the <code>ResourceBundle.Control</code>
2550 * instance used for its current invocation, not on the instance
2551 * used in the invocation that originally loaded the resource
2554 * <p>The default implementation compares <code>loadTime</code> and
2555 * the last modified time of the source data of the resource
2556 * bundle. If it's determined that the source data has been modified
2557 * since <code>loadTime</code>, <code>true</code> is
2558 * returned. Otherwise, <code>false</code> is returned. This
2559 * implementation assumes that the given <code>format</code> is the
2560 * same string as its file suffix if it's not one of the default
2561 * formats, <code>"java.class"</code> or
2562 * <code>"java.properties"</code>.
2565 * the base bundle name of the resource bundle, a
2566 * fully qualified class name
2568 * the locale for which the resource bundle
2569 * should be instantiated
2571 * the resource bundle format to be loaded
2573 * the <code>ClassLoader</code> to use to load the bundle
2575 * the resource bundle instance that has been expired
2578 * the time when <code>bundle</code> was loaded and put
2580 * @return <code>true</code> if the expired bundle needs to be
2581 * reloaded; <code>false</code> otherwise.
2582 * @exception NullPointerException
2583 * if <code>baseName</code>, <code>locale</code>,
2584 * <code>format</code>, <code>loader</code>, or
2585 * <code>bundle</code> is <code>null</code>
2587 public boolean needsReload(String baseName, Locale locale,
2588 String format, ClassLoader loader,
2589 ResourceBundle bundle, long loadTime) {
2590 if (bundle == null) {
2591 throw new NullPointerException();
2593 if (format.equals("java.class") || format.equals("java.properties")) {
2594 format = format.substring(5);
2596 boolean result = false;
2599 String resourceName = toResourceName(toBundleName(baseName, locale), format);
2600 URL url = loader.getResource(resourceName);
2602 long lastModified = 0;
2603 URLConnection connection = url.openConnection();
2604 if (connection != null) {
2605 // disable caches to get the correct data
2606 connection.setUseCaches(false);
2607 if (connection instanceof JarURLConnection) {
2608 JarEntry ent = ((JarURLConnection)connection).getJarEntry();
2610 lastModified = ent.getTime();
2611 if (lastModified == -1) {
2616 lastModified = connection.getLastModified();
2619 result = lastModified >= loadTime;
2622 } catch (NullPointerException npe) {
2624 } catch (Exception e) {
2625 // ignore other exceptions
2631 * Converts the given <code>baseName</code> and <code>locale</code>
2632 * to the bundle name. This method is called from the default
2633 * implementation of the {@link #newBundle(String, Locale, String,
2634 * ClassLoader, boolean) newBundle} and {@link #needsReload(String,
2635 * Locale, String, ClassLoader, ResourceBundle, long) needsReload}
2638 * <p>This implementation returns the following value:
2640 * baseName + "_" + language + "_" + script + "_" + country + "_" + variant
2642 * where <code>language</code>, <code>script</code>, <code>country</code>,
2643 * and <code>variant</code> are the language, script, country, and variant
2644 * values of <code>locale</code>, respectively. Final component values that
2645 * are empty Strings are omitted along with the preceding '_'. When the
2646 * script is empty, the script value is ommitted along with the preceding '_'.
2647 * If all of the values are empty strings, then <code>baseName</code>
2650 * <p>For example, if <code>baseName</code> is
2651 * <code>"baseName"</code> and <code>locale</code> is
2652 * <code>Locale("ja", "", "XX")</code>, then
2653 * <code>"baseName_ja_ _XX"</code> is returned. If the given
2654 * locale is <code>Locale("en")</code>, then
2655 * <code>"baseName_en"</code> is returned.
2657 * <p>Overriding this method allows applications to use different
2658 * conventions in the organization and packaging of localized
2662 * the base name of the resource bundle, a fully
2663 * qualified class name
2665 * the locale for which a resource bundle should be
2667 * @return the bundle name for the resource bundle
2668 * @exception NullPointerException
2669 * if <code>baseName</code> or <code>locale</code>
2670 * is <code>null</code>
2672 public String toBundleName(String baseName, Locale locale) {
2673 if (locale == Locale.ROOT) {
2677 String language = locale.getLanguage();
2678 String script = locale.getScript();
2679 String country = locale.getCountry();
2680 String variant = locale.getVariant();
2682 if (language == "" && country == "" && variant == "") {
2686 StringBuilder sb = new StringBuilder(baseName);
2689 if (variant != "") {
2690 sb.append(language).append('_').append(script).append('_').append(country).append('_').append(variant);
2691 } else if (country != "") {
2692 sb.append(language).append('_').append(script).append('_').append(country);
2694 sb.append(language).append('_').append(script);
2697 if (variant != "") {
2698 sb.append(language).append('_').append(country).append('_').append(variant);
2699 } else if (country != "") {
2700 sb.append(language).append('_').append(country);
2702 sb.append(language);
2705 return sb.toString();
2710 * Converts the given <code>bundleName</code> to the form required
2711 * by the {@link ClassLoader#getResource ClassLoader.getResource}
2712 * method by replacing all occurrences of <code>'.'</code> in
2713 * <code>bundleName</code> with <code>'/'</code> and appending a
2714 * <code>'.'</code> and the given file <code>suffix</code>. For
2715 * example, if <code>bundleName</code> is
2716 * <code>"foo.bar.MyResources_ja_JP"</code> and <code>suffix</code>
2717 * is <code>"properties"</code>, then
2718 * <code>"foo/bar/MyResources_ja_JP.properties"</code> is returned.
2723 * the file type suffix
2724 * @return the converted resource name
2725 * @exception NullPointerException
2726 * if <code>bundleName</code> or <code>suffix</code>
2727 * is <code>null</code>
2729 public final String toResourceName(String bundleName, String suffix) {
2730 StringBuilder sb = new StringBuilder(bundleName.length() + 1 + suffix.length());
2731 sb.append(bundleName.replace('.', '/')).append('.').append(suffix);
2732 return sb.toString();
2736 private static class SingleFormatControl extends Control {
2737 private static final Control PROPERTIES_ONLY
2738 = new SingleFormatControl(FORMAT_PROPERTIES);
2740 private static final Control CLASS_ONLY
2741 = new SingleFormatControl(FORMAT_CLASS);
2743 private final List<String> formats;
2745 protected SingleFormatControl(List<String> formats) {
2746 this.formats = formats;
2749 public List<String> getFormats(String baseName) {
2750 if (baseName == null) {
2751 throw new NullPointerException();
2757 private static final class NoFallbackControl extends SingleFormatControl {
2758 private static final Control NO_FALLBACK
2759 = new NoFallbackControl(FORMAT_DEFAULT);
2761 private static final Control PROPERTIES_ONLY_NO_FALLBACK
2762 = new NoFallbackControl(FORMAT_PROPERTIES);
2764 private static final Control CLASS_ONLY_NO_FALLBACK
2765 = new NoFallbackControl(FORMAT_CLASS);
2767 protected NoFallbackControl(List<String> formats) {
2771 public Locale getFallbackLocale(String baseName, Locale locale) {
2772 if (baseName == null || locale == null) {
2773 throw new NullPointerException();