1 /*
   2  * Copyright (c) 1996, 2016, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.  Oracle designates this
   8  * particular file as subject to the "Classpath" exception as provided
   9  * by Oracle in the LICENSE file that accompanied this code.
  10  *
  11  * This code is distributed in the hope that it will be useful, but WITHOUT
  12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  14  * version 2 for more details (a copy is included in the LICENSE file that
  15  * accompanied this code).
  16  *
  17  * You should have received a copy of the GNU General Public License version
  18  * 2 along with this work; if not, write to the Free Software Foundation,
  19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  20  *
  21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  22  * or visit www.oracle.com if you need additional information or have any
  23  * questions.
  24  */
  25 
  26 /*
  27  * (C) Copyright Taligent, Inc. 1996, 1997 - All Rights Reserved
  28  * (C) Copyright IBM Corp. 1996 - 1999 - All Rights Reserved
  29  *
  30  * The original version of this source code and documentation
  31  * is copyrighted and owned by Taligent, Inc., a wholly-owned
  32  * subsidiary of IBM. These materials are provided under terms
  33  * of a License Agreement between Taligent and Sun. This technology
  34  * is protected by multiple US and International patents.
  35  *
  36  * This notice and attribution to Taligent may not be removed.
  37  * Taligent is a registered trademark of Taligent, Inc.
  38  *
  39  */
  40 
  41 package java.util;
  42 
  43 import java.io.IOException;
  44 import java.io.InputStream;
  45 import java.io.UncheckedIOException;
  46 import java.lang.ref.ReferenceQueue;
  47 import java.lang.ref.SoftReference;
  48 import java.lang.ref.WeakReference;
  49 import java.lang.reflect.Constructor;
  50 import java.lang.reflect.InvocationTargetException;
  51 import java.lang.reflect.Modifier;
  52 import java.lang.reflect.Module;
  53 import java.net.JarURLConnection;
  54 import java.net.URL;
  55 import java.net.URLConnection;
  56 import java.security.AccessController;
  57 import java.security.PrivilegedAction;
  58 import java.security.PrivilegedActionException;
  59 import java.security.PrivilegedExceptionAction;
  60 import java.util.concurrent.ConcurrentHashMap;
  61 import java.util.concurrent.ConcurrentMap;
  62 import java.util.jar.JarEntry;
  63 import java.util.spi.ResourceBundleControlProvider;
  64 import java.util.spi.ResourceBundleProvider;
  65 
  66 import jdk.internal.loader.BootLoader;
  67 import jdk.internal.misc.JavaUtilResourceBundleAccess;
  68 import jdk.internal.misc.SharedSecrets;
  69 import jdk.internal.reflect.CallerSensitive;
  70 import jdk.internal.reflect.Reflection;
  71 import sun.security.action.GetPropertyAction;
  72 import sun.util.locale.BaseLocale;
  73 import sun.util.locale.LocaleObjectCache;
  74 import static sun.security.util.SecurityConstants.GET_CLASSLOADER_PERMISSION;
  75 
  76 
  77 /**
  78  *
  79  * Resource bundles contain locale-specific objects.  When your program needs a
  80  * locale-specific resource, a <code>String</code> for example, your program can
  81  * load it from the resource bundle that is appropriate for the current user's
  82  * locale. In this way, you can write program code that is largely independent
  83  * of the user's locale isolating most, if not all, of the locale-specific
  84  * information in resource bundles.
  85  *
  86  * <p>
  87  * This allows you to write programs that can:
  88  * <UL>
  89  * <LI> be easily localized, or translated, into different languages
  90  * <LI> handle multiple locales at once
  91  * <LI> be easily modified later to support even more locales
  92  * </UL>
  93  *
  94  * <P>
  95  * Resource bundles belong to families whose members share a common base
  96  * name, but whose names also have additional components that identify
  97  * their locales. For example, the base name of a family of resource
  98  * bundles might be "MyResources". The family should have a default
  99  * resource bundle which simply has the same name as its family -
 100  * "MyResources" - and will be used as the bundle of last resort if a
 101  * specific locale is not supported. The family can then provide as
 102  * many locale-specific members as needed, for example a German one
 103  * named "MyResources_de".
 104  *
 105  * <P>
 106  * Each resource bundle in a family contains the same items, but the items have
 107  * been translated for the locale represented by that resource bundle.
 108  * For example, both "MyResources" and "MyResources_de" may have a
 109  * <code>String</code> that's used on a button for canceling operations.
 110  * In "MyResources" the <code>String</code> may contain "Cancel" and in
 111  * "MyResources_de" it may contain "Abbrechen".
 112  *
 113  * <P>
 114  * If there are different resources for different countries, you
 115  * can make specializations: for example, "MyResources_de_CH" contains objects for
 116  * the German language (de) in Switzerland (CH). If you want to only
 117  * modify some of the resources
 118  * in the specialization, you can do so.
 119  *
 120  * <P>
 121  * When your program needs a locale-specific object, it loads
 122  * the <code>ResourceBundle</code> class using the
 123  * {@link #getBundle(java.lang.String, java.util.Locale) getBundle}
 124  * method:
 125  * <blockquote>
 126  * <pre>
 127  * ResourceBundle myResources =
 128  *      ResourceBundle.getBundle("MyResources", currentLocale);
 129  * </pre>
 130  * </blockquote>
 131  *
 132  * <P>
 133  * Resource bundles contain key/value pairs. The keys uniquely
 134  * identify a locale-specific object in the bundle. Here's an
 135  * example of a <code>ListResourceBundle</code> that contains
 136  * two key/value pairs:
 137  * <blockquote>
 138  * <pre>
 139  * public class MyResources extends ListResourceBundle {
 140  *     protected Object[][] getContents() {
 141  *         return new Object[][] {
 142  *             // LOCALIZE THE SECOND STRING OF EACH ARRAY (e.g., "OK")
 143  *             {"OkKey", "OK"},
 144  *             {"CancelKey", "Cancel"},
 145  *             // END OF MATERIAL TO LOCALIZE
 146  *        };
 147  *     }
 148  * }
 149  * </pre>
 150  * </blockquote>
 151  * Keys are always <code>String</code>s.
 152  * In this example, the keys are "OkKey" and "CancelKey".
 153  * In the above example, the values
 154  * are also <code>String</code>s--"OK" and "Cancel"--but
 155  * they don't have to be. The values can be any type of object.
 156  *
 157  * <P>
 158  * You retrieve an object from resource bundle using the appropriate
 159  * getter method. Because "OkKey" and "CancelKey"
 160  * are both strings, you would use <code>getString</code> to retrieve them:
 161  * <blockquote>
 162  * <pre>
 163  * button1 = new Button(myResources.getString("OkKey"));
 164  * button2 = new Button(myResources.getString("CancelKey"));
 165  * </pre>
 166  * </blockquote>
 167  * The getter methods all require the key as an argument and return
 168  * the object if found. If the object is not found, the getter method
 169  * throws a <code>MissingResourceException</code>.
 170  *
 171  * <P>
 172  * Besides <code>getString</code>, <code>ResourceBundle</code> also provides
 173  * a method for getting string arrays, <code>getStringArray</code>,
 174  * as well as a generic <code>getObject</code> method for any other
 175  * type of object. When using <code>getObject</code>, you'll
 176  * have to cast the result to the appropriate type. For example:
 177  * <blockquote>
 178  * <pre>
 179  * int[] myIntegers = (int[]) myResources.getObject("intList");
 180  * </pre>
 181  * </blockquote>
 182  *
 183  * <P>
 184  * The Java Platform provides two subclasses of <code>ResourceBundle</code>,
 185  * <code>ListResourceBundle</code> and <code>PropertyResourceBundle</code>,
 186  * that provide a fairly simple way to create resources.
 187  * As you saw briefly in a previous example, <code>ListResourceBundle</code>
 188  * manages its resource as a list of key/value pairs.
 189  * <code>PropertyResourceBundle</code> uses a properties file to manage
 190  * its resources.
 191  *
 192  * <p>
 193  * If <code>ListResourceBundle</code> or <code>PropertyResourceBundle</code>
 194  * do not suit your needs, you can write your own <code>ResourceBundle</code>
 195  * subclass.  Your subclasses must override two methods: <code>handleGetObject</code>
 196  * and <code>getKeys()</code>.
 197  *
 198  * <p>
 199  * The implementation of a {@code ResourceBundle} subclass must be thread-safe
 200  * if it's simultaneously used by multiple threads. The default implementations
 201  * of the non-abstract methods in this class, and the methods in the direct
 202  * known concrete subclasses {@code ListResourceBundle} and
 203  * {@code PropertyResourceBundle} are thread-safe.
 204  *
 205  * <h3><a name="bundleprovider">Resource Bundles in Named Modules</a></h3>
 206  *
 207  * When resource bundles are deployed in named modules, the following
 208  * module-specific requirements and restrictions are applied.
 209  *
 210  * <ul>
 211  * <li>Code in a named module that calls {@link #getBundle(String, Locale)}
 212  * will locate resource bundles in the caller's module (<em>caller module</em>).</li>
 213  * <li>If resource bundles are deployed in named modules separate from
 214  * the caller module, those resource bundles need to be loaded from service
 215  * providers of {@link ResourceBundleProvider}. The caller module must declare
 216  * "{@code uses}" and the service interface name is the concatenation of the
 217  * base name of the bundles and the string "{@code Provider}". The
 218  * <em>bundle provider modules</em> containing resource bundles must
 219  * declare "{@code provides}" with the service interface name and
 220  * its implementation class name. For example, if the base name is
 221  * "{@code com.example.app.MyResources}", the caller module must declare
 222  * "{@code uses com.example.app.MyResourcesProvider;}" and a module containing resource
 223  * bundles must declare "{@code provides com.example.app.MyResourcesProvider
 224  * with com.example.app.internal.MyResourcesProviderImpl;}"
 225  * where {@code com.example.app.internal.MyResourcesProviderImpl} is an
 226  * implementation class of {@code com.example.app.MyResourcesProvider}.</li>
 227  * <li>If you want to use non-standard formats in named modules, such as XML,
 228  * {@link ResourceBundleProvider} needs to be used.</li>
 229  * <li>The {@code getBundle} method with a {@code ClassLoader} may not be able to
 230  * find resource bundles using the given {@code ClassLoader} in named modules.
 231  * The {@code getBundle} method with a {@code Module} can be used, instead.</li>
 232  * <li>{@code ResourceBundle.Control} is <em>not</em> supported in named modules.
 233  * If the {@code getBundle} method with a {@code ResourceBundle.Control} is called
 234  * in a named module, the method will throw an {@code UnsupportedOperationException}.
 235  * Any service providers of {@link ResourceBundleControlProvider} are ignored in
 236  * named modules.
 237  * </li>
 238  * </ul>
 239  *
 240  * <h3><a name="RBP_support">ResourceBundleProvider Service Providers</a></h3>
 241  *
 242  * The {@code getBundle} factory methods load service providers of
 243  * {@link ResourceBundleProvider}, if available, using {@link ServiceLoader}.
 244  * The service type is designated by {@code basename+"Provider"}. For
 245  * example, if the base name is "{@code com.example.app.MyResources}", the service
 246  * type is {@code com.example.app.MyResourcesProvider}.
 247  * <p>
 248  * In named modules, the loaded service providers for the given base name are
 249  * used to load resource bundles. If no service provider is available, or if
 250  * none of the service providers returns a resource bundle and the caller module
 251  * doesn't have its own service provider, the {@code getBundle} factory method
 252  * searches for resource bundles that are local in the caller module and that
 253  * are visible to the class loader of the caller module.  The resource bundle
 254  * formats for local module searching are "java.class" and "java.properties".
 255  *
 256  * <h3>ResourceBundle.Control</h3>
 257  *
 258  * The {@link ResourceBundle.Control} class provides information necessary
 259  * to perform the bundle loading process by the <code>getBundle</code>
 260  * factory methods that take a <code>ResourceBundle.Control</code>
 261  * instance. You can implement your own subclass in order to enable
 262  * non-standard resource bundle formats, change the search strategy, or
 263  * define caching parameters. Refer to the descriptions of the class and the
 264  * {@link #getBundle(String, Locale, ClassLoader, Control) getBundle}
 265  * factory method for details.
 266  *
 267  * <p><a name="modify_default_behavior">For the {@code getBundle} factory</a>
 268  * methods that take no {@link Control} instance, their <a
 269  * href="#default_behavior"> default behavior</a> of resource bundle loading
 270  * can be modified with <em>installed</em> {@link
 271  * ResourceBundleControlProvider} implementations. Any installed providers are
 272  * detected at the {@code ResourceBundle} class loading time. If any of the
 273  * providers provides a {@link Control} for the given base name, that {@link
 274  * Control} will be used instead of the default {@link Control}. If there is
 275  * more than one service provider installed for supporting the same base name,
 276  * the first one returned from {@link ServiceLoader} will be used.
 277  *
 278  * <h3>Cache Management</h3>
 279  *
 280  * Resource bundle instances created by the <code>getBundle</code> factory
 281  * methods are cached by default, and the factory methods return the same
 282  * resource bundle instance multiple times if it has been
 283  * cached. <code>getBundle</code> clients may clear the cache, manage the
 284  * lifetime of cached resource bundle instances using time-to-live values,
 285  * or specify not to cache resource bundle instances. Refer to the
 286  * descriptions of the {@linkplain #getBundle(String, Locale, ClassLoader,
 287  * Control) <code>getBundle</code> factory method}, {@link
 288  * #clearCache(ClassLoader) clearCache}, {@link
 289  * Control#getTimeToLive(String, Locale)
 290  * ResourceBundle.Control.getTimeToLive}, and {@link
 291  * Control#needsReload(String, Locale, String, ClassLoader, ResourceBundle,
 292  * long) ResourceBundle.Control.needsReload} for details.
 293  *
 294  * <h3>Example</h3>
 295  *
 296  * The following is a very simple example of a <code>ResourceBundle</code>
 297  * subclass, <code>MyResources</code>, that manages two resources (for a larger number of
 298  * resources you would probably use a <code>Map</code>).
 299  * Notice that you don't need to supply a value if
 300  * a "parent-level" <code>ResourceBundle</code> handles the same
 301  * key with the same value (as for the okKey below).
 302  * <blockquote>
 303  * <pre>
 304  * // default (English language, United States)
 305  * public class MyResources extends ResourceBundle {
 306  *     public Object handleGetObject(String key) {
 307  *         if (key.equals("okKey")) return "Ok";
 308  *         if (key.equals("cancelKey")) return "Cancel";
 309  *         return null;
 310  *     }
 311  *
 312  *     public Enumeration&lt;String&gt; getKeys() {
 313  *         return Collections.enumeration(keySet());
 314  *     }
 315  *
 316  *     // Overrides handleKeySet() so that the getKeys() implementation
 317  *     // can rely on the keySet() value.
 318  *     protected Set&lt;String&gt; handleKeySet() {
 319  *         return new HashSet&lt;String&gt;(Arrays.asList("okKey", "cancelKey"));
 320  *     }
 321  * }
 322  *
 323  * // German language
 324  * public class MyResources_de extends MyResources {
 325  *     public Object handleGetObject(String key) {
 326  *         // don't need okKey, since parent level handles it.
 327  *         if (key.equals("cancelKey")) return "Abbrechen";
 328  *         return null;
 329  *     }
 330  *
 331  *     protected Set&lt;String&gt; handleKeySet() {
 332  *         return new HashSet&lt;String&gt;(Arrays.asList("cancelKey"));
 333  *     }
 334  * }
 335  * </pre>
 336  * </blockquote>
 337  * You do not have to restrict yourself to using a single family of
 338  * <code>ResourceBundle</code>s. For example, you could have a set of bundles for
 339  * exception messages, <code>ExceptionResources</code>
 340  * (<code>ExceptionResources_fr</code>, <code>ExceptionResources_de</code>, ...),
 341  * and one for widgets, <code>WidgetResource</code> (<code>WidgetResources_fr</code>,
 342  * <code>WidgetResources_de</code>, ...); breaking up the resources however you like.
 343  *
 344  * @see ListResourceBundle
 345  * @see PropertyResourceBundle
 346  * @see MissingResourceException
 347  * @see ResourceBundleProvider
 348  * @since 1.1
 349  */
 350 public abstract class ResourceBundle {
 351 
 352     /** initial size of the bundle cache */
 353     private static final int INITIAL_CACHE_SIZE = 32;
 354 
 355     static {
 356         SharedSecrets.setJavaUtilResourceBundleAccess(
 357             new JavaUtilResourceBundleAccess() {
 358                 @Override
 359                 public void setParent(ResourceBundle bundle,
 360                                       ResourceBundle parent) {
 361                     bundle.setParent(parent);
 362                 }
 363 
 364                 @Override
 365                 public ResourceBundle getParent(ResourceBundle bundle) {
 366                     return bundle.parent;
 367                 }
 368 
 369                 @Override
 370                 public void setLocale(ResourceBundle bundle, Locale locale) {
 371                     bundle.locale = locale;
 372                 }
 373 
 374                 @Override
 375                 public void setName(ResourceBundle bundle, String name) {
 376                     bundle.name = name;
 377                 }
 378 
 379                 @Override
 380                 public ResourceBundle getBundle(String baseName, Locale locale, Module module) {
 381                     // use the given module as the caller to bypass the access check
 382                     return getBundleImpl(module, module, getLoader(module),
 383                                          baseName, locale, Control.INSTANCE);
 384                 }
 385 
 386                 @Override
 387                 public ResourceBundle newResourceBundle(Class<? extends ResourceBundle> bundleClass) {
 388                     return ResourceBundleProviderHelper.newResourceBundle(bundleClass);
 389                 }
 390             });
 391     }
 392 
 393     /** constant indicating that no resource bundle exists */
 394     private static final ResourceBundle NONEXISTENT_BUNDLE = new ResourceBundle() {
 395             public Enumeration<String> getKeys() { return null; }
 396             protected Object handleGetObject(String key) { return null; }
 397             public String toString() { return "NONEXISTENT_BUNDLE"; }
 398         };
 399 
 400 
 401     /**
 402      * The cache is a map from cache keys (with bundle base name, locale, and
 403      * class loader) to either a resource bundle or NONEXISTENT_BUNDLE wrapped by a
 404      * BundleReference.
 405      *
 406      * The cache is a ConcurrentMap, allowing the cache to be searched
 407      * concurrently by multiple threads.  This will also allow the cache keys
 408      * to be reclaimed along with the ClassLoaders they reference.
 409      *
 410      * This variable would be better named "cache", but we keep the old
 411      * name for compatibility with some workarounds for bug 4212439.
 412      */
 413     private static final ConcurrentMap<CacheKey, BundleReference> cacheList
 414         = new ConcurrentHashMap<>(INITIAL_CACHE_SIZE);
 415 
 416     /**
 417      * Queue for reference objects referring to class loaders or bundles.
 418      */
 419     private static final ReferenceQueue<Object> referenceQueue = new ReferenceQueue<>();
 420 
 421     /**
 422      * Returns the base name of this bundle, if known, or {@code null} if unknown.
 423      *
 424      * If not null, then this is the value of the {@code baseName} parameter
 425      * that was passed to the {@code ResourceBundle.getBundle(...)} method
 426      * when the resource bundle was loaded.
 427      *
 428      * @return The base name of the resource bundle, as provided to and expected
 429      * by the {@code ResourceBundle.getBundle(...)} methods.
 430      *
 431      * @see #getBundle(java.lang.String, java.util.Locale, java.lang.ClassLoader)
 432      *
 433      * @since 1.8
 434      */
 435     public String getBaseBundleName() {
 436         return name;
 437     }
 438 
 439     /**
 440      * The parent bundle of this bundle.
 441      * The parent bundle is searched by {@link #getObject getObject}
 442      * when this bundle does not contain a particular resource.
 443      */
 444     protected ResourceBundle parent = null;
 445 
 446     /**
 447      * The locale for this bundle.
 448      */
 449     private Locale locale = null;
 450 
 451     /**
 452      * The base bundle name for this bundle.
 453      */
 454     private String name;
 455 
 456     /**
 457      * The flag indicating this bundle has expired in the cache.
 458      */
 459     private volatile boolean expired;
 460 
 461     /**
 462      * The back link to the cache key. null if this bundle isn't in
 463      * the cache (yet) or has expired.
 464      */
 465     private volatile CacheKey cacheKey;
 466 
 467     /**
 468      * A Set of the keys contained only in this ResourceBundle.
 469      */
 470     private volatile Set<String> keySet;
 471 
 472     private static final List<ResourceBundleControlProvider> providers;
 473 
 474     static {
 475         List<ResourceBundleControlProvider> list = null;
 476         ServiceLoader<ResourceBundleControlProvider> serviceLoaders
 477                 = ServiceLoader.loadInstalled(ResourceBundleControlProvider.class);
 478         for (ResourceBundleControlProvider provider : serviceLoaders) {
 479             if (list == null) {
 480                 list = new ArrayList<>();
 481             }
 482             list.add(provider);
 483         }
 484         providers = list;
 485     }
 486 
 487     /**
 488      * Sole constructor.  (For invocation by subclass constructors, typically
 489      * implicit.)
 490      */
 491     public ResourceBundle() {
 492     }
 493 
 494     /**
 495      * Gets a string for the given key from this resource bundle or one of its parents.
 496      * Calling this method is equivalent to calling
 497      * <blockquote>
 498      * <code>(String) {@link #getObject(java.lang.String) getObject}(key)</code>.
 499      * </blockquote>
 500      *
 501      * @param key the key for the desired string
 502      * @exception NullPointerException if <code>key</code> is <code>null</code>
 503      * @exception MissingResourceException if no object for the given key can be found
 504      * @exception ClassCastException if the object found for the given key is not a string
 505      * @return the string for the given key
 506      */
 507     public final String getString(String key) {
 508         return (String) getObject(key);
 509     }
 510 
 511     /**
 512      * Gets a string array for the given key from this resource bundle or one of its parents.
 513      * Calling this method is equivalent to calling
 514      * <blockquote>
 515      * <code>(String[]) {@link #getObject(java.lang.String) getObject}(key)</code>.
 516      * </blockquote>
 517      *
 518      * @param key the key for the desired string array
 519      * @exception NullPointerException if <code>key</code> is <code>null</code>
 520      * @exception MissingResourceException if no object for the given key can be found
 521      * @exception ClassCastException if the object found for the given key is not a string array
 522      * @return the string array for the given key
 523      */
 524     public final String[] getStringArray(String key) {
 525         return (String[]) getObject(key);
 526     }
 527 
 528     /**
 529      * Gets an object for the given key from this resource bundle or one of its parents.
 530      * This method first tries to obtain the object from this resource bundle using
 531      * {@link #handleGetObject(java.lang.String) handleGetObject}.
 532      * If not successful, and the parent resource bundle is not null,
 533      * it calls the parent's <code>getObject</code> method.
 534      * If still not successful, it throws a MissingResourceException.
 535      *
 536      * @param key the key for the desired object
 537      * @exception NullPointerException if <code>key</code> is <code>null</code>
 538      * @exception MissingResourceException if no object for the given key can be found
 539      * @return the object for the given key
 540      */
 541     public final Object getObject(String key) {
 542         Object obj = handleGetObject(key);
 543         if (obj == null) {
 544             if (parent != null) {
 545                 obj = parent.getObject(key);
 546             }
 547             if (obj == null) {
 548                 throw new MissingResourceException("Can't find resource for bundle "
 549                                                    +this.getClass().getName()
 550                                                    +", key "+key,
 551                                                    this.getClass().getName(),
 552                                                    key);
 553             }
 554         }
 555         return obj;
 556     }
 557 
 558     /**
 559      * Returns the locale of this resource bundle. This method can be used after a
 560      * call to getBundle() to determine whether the resource bundle returned really
 561      * corresponds to the requested locale or is a fallback.
 562      *
 563      * @return the locale of this resource bundle
 564      */
 565     public Locale getLocale() {
 566         return locale;
 567     }
 568 
 569     /*
 570      * Automatic determination of the ClassLoader to be used to load
 571      * resources on behalf of the client.
 572      */
 573     private static ClassLoader getLoader(Class<?> caller) {
 574         ClassLoader cl = caller == null ? null : caller.getClassLoader();
 575         if (cl == null) {
 576             // When the caller's loader is the boot class loader, cl is null
 577             // here. In that case, ClassLoader.getSystemClassLoader() may
 578             // return the same class loader that the application is
 579             // using. We therefore use a wrapper ClassLoader to create a
 580             // separate scope for bundles loaded on behalf of the Java
 581             // runtime so that these bundles cannot be returned from the
 582             // cache to the application (5048280).
 583             cl = RBClassLoader.INSTANCE;
 584         }
 585         return cl;
 586     }
 587 
 588     private static ClassLoader getLoader(Module module) {
 589         PrivilegedAction<ClassLoader> pa = module::getClassLoader;
 590         return AccessController.doPrivileged(pa);
 591     }
 592 
 593     /**
 594      * A wrapper of ClassLoader.getSystemClassLoader().
 595      */
 596     private static class RBClassLoader extends ClassLoader {
 597         private static final RBClassLoader INSTANCE = AccessController.doPrivileged(
 598                     new PrivilegedAction<RBClassLoader>() {
 599                         public RBClassLoader run() {
 600                             return new RBClassLoader();
 601                         }
 602                     });
 603         private RBClassLoader() {
 604         }
 605         public Class<?> loadClass(String name) throws ClassNotFoundException {
 606             ClassLoader loader = ClassLoader.getSystemClassLoader();
 607             if (loader != null) {
 608                 return loader.loadClass(name);
 609             }
 610             return Class.forName(name);
 611         }
 612         public URL getResource(String name) {
 613             ClassLoader loader = ClassLoader.getSystemClassLoader();
 614             if (loader != null) {
 615                 return loader.getResource(name);
 616             }
 617             return ClassLoader.getSystemResource(name);
 618         }
 619         public InputStream getResourceAsStream(String name) {
 620             ClassLoader loader = ClassLoader.getSystemClassLoader();
 621             if (loader != null) {
 622                 return loader.getResourceAsStream(name);
 623             }
 624             return ClassLoader.getSystemResourceAsStream(name);
 625         }
 626     }
 627 
 628     /**
 629      * Sets the parent bundle of this bundle.
 630      * The parent bundle is searched by {@link #getObject getObject}
 631      * when this bundle does not contain a particular resource.
 632      *
 633      * @param parent this bundle's parent bundle.
 634      */
 635     protected void setParent(ResourceBundle parent) {
 636         assert parent != NONEXISTENT_BUNDLE;
 637         this.parent = parent;
 638     }
 639 
 640     /**
 641      * Key used for cached resource bundles.  The key checks the base
 642      * name, the locale, the class loader, and the caller module
 643      * to determine if the resource is a match to the requested one.
 644      * The loader may be null, but the base name, the locale and
 645      * module must have a non-null value.
 646      */
 647     private static class CacheKey implements Cloneable {
 648         // These four are the actual keys for lookup in Map.
 649         private String name;
 650         private Locale locale;
 651         private KeyElementReference<ClassLoader> loaderRef;
 652         private KeyElementReference<Module> moduleRef;
 653         private KeyElementReference<Module> callerRef;
 654 
 655 
 656         // bundle format which is necessary for calling
 657         // Control.needsReload().
 658         private String format;
 659 
 660         // These time values are in CacheKey so that NONEXISTENT_BUNDLE
 661         // doesn't need to be cloned for caching.
 662 
 663         // The time when the bundle has been loaded
 664         private volatile long loadTime;
 665 
 666         // The time when the bundle expires in the cache, or either
 667         // Control.TTL_DONT_CACHE or Control.TTL_NO_EXPIRATION_CONTROL.
 668         private volatile long expirationTime;
 669 
 670         // Placeholder for an error report by a Throwable
 671         private Throwable cause;
 672 
 673         // Hash code value cache to avoid recalculating the hash code
 674         // of this instance.
 675         private int hashCodeCache;
 676 
 677         // ResourceBundleProviders for loading ResourceBundles
 678         private ServiceLoader<ResourceBundleProvider> providers;
 679         private boolean providersChecked;
 680 
 681         // Boolean.TRUE if the factory method caller provides a ResourceBundleProvier.
 682         private Boolean callerHasProvider;
 683 
 684         CacheKey(String baseName, Locale locale, ClassLoader loader, Module module, Module caller) {
 685             Objects.requireNonNull(module);
 686 
 687             this.name = baseName;
 688             this.locale = locale;
 689             if (loader == null) {
 690                 this.loaderRef = null;
 691             } else {
 692                 this.loaderRef = new KeyElementReference<>(loader, referenceQueue, this);
 693             }
 694             this.moduleRef = new KeyElementReference<>(module, referenceQueue, this);
 695             this.callerRef = new KeyElementReference<>(caller, referenceQueue, this);
 696 
 697             calculateHashCode();
 698         }
 699 
 700         String getName() {
 701             return name;
 702         }
 703 
 704         CacheKey setName(String baseName) {
 705             if (!this.name.equals(baseName)) {
 706                 this.name = baseName;
 707                 calculateHashCode();
 708             }
 709             return this;
 710         }
 711 
 712         Locale getLocale() {
 713             return locale;
 714         }
 715 
 716         CacheKey setLocale(Locale locale) {
 717             if (!this.locale.equals(locale)) {
 718                 this.locale = locale;
 719                 calculateHashCode();
 720             }
 721             return this;
 722         }
 723 
 724         ClassLoader getLoader() {
 725             return (loaderRef != null) ? loaderRef.get() : null;
 726         }
 727 
 728         Module getModule() {
 729             return moduleRef.get();
 730         }
 731 
 732         Module getCallerModule() {
 733             return callerRef.get();
 734         }
 735 
 736         ServiceLoader<ResourceBundleProvider> getProviders() {
 737             if (!providersChecked) {
 738                 providers = getServiceLoader(getModule(), name);
 739                 providersChecked = true;
 740             }
 741             return providers;
 742         }
 743 
 744         boolean hasProviders() {
 745             return getProviders() != null;
 746         }
 747 
 748         boolean callerHasProvider() {
 749             return callerHasProvider == Boolean.TRUE;
 750         }
 751 
 752         @Override
 753         public boolean equals(Object other) {
 754             if (this == other) {
 755                 return true;
 756             }
 757             try {
 758                 final CacheKey otherEntry = (CacheKey)other;
 759                 //quick check to see if they are not equal
 760                 if (hashCodeCache != otherEntry.hashCodeCache) {
 761                     return false;
 762                 }
 763                 //are the names the same?
 764                 if (!name.equals(otherEntry.name)) {
 765                     return false;
 766                 }
 767                 // are the locales the same?
 768                 if (!locale.equals(otherEntry.locale)) {
 769                     return false;
 770                 }
 771                 //are refs (both non-null) or (both null)?
 772                 if (loaderRef == null) {
 773                     return otherEntry.loaderRef == null;
 774                 }
 775                 ClassLoader loader = getLoader();
 776                 Module module = getModule();
 777                 Module caller = getCallerModule();
 778 
 779                 return (otherEntry.loaderRef != null)
 780                         // with a null reference we can no longer find
 781                         // out which class loader or module was referenced; so
 782                         // treat it as unequal
 783                         && (loader != null)
 784                         && (loader == otherEntry.getLoader())
 785                         && (module != null)
 786                         && (module.equals(otherEntry.getModule()))
 787                         && (caller != null)
 788                         && (caller.equals(otherEntry.getCallerModule()));
 789             } catch (NullPointerException | ClassCastException e) {
 790             }
 791             return false;
 792         }
 793 
 794         @Override
 795         public int hashCode() {
 796             return hashCodeCache;
 797         }
 798 
 799         private void calculateHashCode() {
 800             hashCodeCache = name.hashCode() << 3;
 801             hashCodeCache ^= locale.hashCode();
 802             ClassLoader loader = getLoader();
 803             if (loader != null) {
 804                 hashCodeCache ^= loader.hashCode();
 805             }
 806             Module module = getModule();
 807             if (module != null) {
 808                 hashCodeCache ^= module.hashCode();
 809             }
 810             Module caller = getCallerModule();
 811             if (caller != null) {
 812                 hashCodeCache ^= caller.hashCode();
 813             }
 814         }
 815 
 816         @Override
 817         public Object clone() {
 818             try {
 819                 CacheKey clone = (CacheKey) super.clone();
 820                 if (loaderRef != null) {
 821                     clone.loaderRef = new KeyElementReference<>(getLoader(),
 822                                                                 referenceQueue, clone);
 823                 }
 824                 clone.moduleRef = new KeyElementReference<>(getModule(),
 825                                                             referenceQueue, clone);
 826                 clone.callerRef = new KeyElementReference<>(getCallerModule(),
 827                                                             referenceQueue, clone);
 828 
 829                 // Clear the reference to ResourceBundleProviders and the flag
 830                 clone.providers = null;
 831                 clone.providersChecked = false;
 832                 // Clear the reference to a Throwable
 833                 clone.cause = null;
 834                 // Clear callerHasProvider
 835                 clone.callerHasProvider = null;
 836                 return clone;
 837             } catch (CloneNotSupportedException e) {
 838                 //this should never happen
 839                 throw new InternalError(e);
 840             }
 841         }
 842 
 843         String getFormat() {
 844             return format;
 845         }
 846 
 847         void setFormat(String format) {
 848             this.format = format;
 849         }
 850 
 851         private void setCause(Throwable cause) {
 852             if (this.cause == null) {
 853                 this.cause = cause;
 854             } else {
 855                 // Override the cause if the previous one is
 856                 // ClassNotFoundException.
 857                 if (this.cause instanceof ClassNotFoundException) {
 858                     this.cause = cause;
 859                 }
 860             }
 861         }
 862 
 863         private Throwable getCause() {
 864             return cause;
 865         }
 866 
 867         @Override
 868         public String toString() {
 869             String l = locale.toString();
 870             if (l.length() == 0) {
 871                 if (locale.getVariant().length() != 0) {
 872                     l = "__" + locale.getVariant();
 873                 } else {
 874                     l = "\"\"";
 875                 }
 876             }
 877             return "CacheKey[" + name + ", lc=" + l + ", ldr=" + getLoader()
 878                 + "(format=" + format + ")]";
 879         }
 880     }
 881 
 882     /**
 883      * The common interface to get a CacheKey in LoaderReference and
 884      * BundleReference.
 885      */
 886     private static interface CacheKeyReference {
 887         public CacheKey getCacheKey();
 888     }
 889 
 890     /**
 891      * References to a CacheKey element as a WeakReference so that it can be
 892      * garbage collected when nobody else is using it.
 893      */
 894     private static class KeyElementReference<T> extends WeakReference<T>
 895                                                 implements CacheKeyReference {
 896         private final CacheKey cacheKey;
 897 
 898         KeyElementReference(T referent, ReferenceQueue<Object> q, CacheKey key) {
 899             super(referent, q);
 900             cacheKey = key;
 901         }
 902 
 903         @Override
 904         public CacheKey getCacheKey() {
 905             return cacheKey;
 906         }
 907     }
 908 
 909     /**
 910      * References to bundles are soft references so that they can be garbage
 911      * collected when they have no hard references.
 912      */
 913     private static class BundleReference extends SoftReference<ResourceBundle>
 914                                          implements CacheKeyReference {
 915         private final CacheKey cacheKey;
 916 
 917         BundleReference(ResourceBundle referent, ReferenceQueue<Object> q, CacheKey key) {
 918             super(referent, q);
 919             cacheKey = key;
 920         }
 921 
 922         @Override
 923         public CacheKey getCacheKey() {
 924             return cacheKey;
 925         }
 926     }
 927 
 928     /**
 929      * Gets a resource bundle using the specified base name, the default locale,
 930      * and the caller's class loader. Calling this method is equivalent to calling
 931      * <blockquote>
 932      * <code>getBundle(baseName, Locale.getDefault(), this.getClass().getClassLoader())</code>,
 933      * </blockquote>
 934      * except that <code>getClassLoader()</code> is run with the security
 935      * privileges of <code>ResourceBundle</code>.
 936      * See {@link #getBundle(String, Locale, ClassLoader) getBundle}
 937      * for a complete description of the search and instantiation strategy.
 938      *
 939      * @param baseName the base name of the resource bundle, a fully qualified class name
 940      * @exception java.lang.NullPointerException
 941      *     if <code>baseName</code> is <code>null</code>
 942      * @exception MissingResourceException
 943      *     if no resource bundle for the specified base name can be found
 944      * @return a resource bundle for the given base name and the default locale
 945      */
 946     @CallerSensitive
 947     public static final ResourceBundle getBundle(String baseName)
 948     {
 949         Class<?> caller = Reflection.getCallerClass();
 950         return getBundleImpl(baseName, Locale.getDefault(),
 951                              caller, getDefaultControl(caller, baseName));
 952     }
 953 
 954     /**
 955      * Returns a resource bundle using the specified base name, the
 956      * default locale and the specified control. Calling this method
 957      * is equivalent to calling
 958      * <pre>
 959      * getBundle(baseName, Locale.getDefault(),
 960      *           this.getClass().getClassLoader(), control),
 961      * </pre>
 962      * except that <code>getClassLoader()</code> is run with the security
 963      * privileges of <code>ResourceBundle</code>.  See {@link
 964      * #getBundle(String, Locale, ClassLoader, Control) getBundle} for the
 965      * complete description of the resource bundle loading process with a
 966      * <code>ResourceBundle.Control</code>.
 967      *
 968      * @param baseName
 969      *        the base name of the resource bundle, a fully qualified class
 970      *        name
 971      * @param control
 972      *        the control which gives information for the resource bundle
 973      *        loading process
 974      * @return a resource bundle for the given base name and the default locale
 975      * @throws NullPointerException
 976      *         if <code>baseName</code> or <code>control</code> is
 977      *         <code>null</code>
 978      * @throws MissingResourceException
 979      *         if no resource bundle for the specified base name can be found
 980      * @throws IllegalArgumentException
 981      *         if the given <code>control</code> doesn't perform properly
 982      *         (e.g., <code>control.getCandidateLocales</code> returns null.)
 983      *         Note that validation of <code>control</code> is performed as
 984      *         needed.
 985      * @throws UnsupportedOperationException
 986      *         if this method is called in a named module
 987      * @since 1.6
 988      */
 989     @CallerSensitive
 990     public static final ResourceBundle getBundle(String baseName,
 991                                                  Control control) {
 992         Class<?> caller = Reflection.getCallerClass();
 993         Locale targetLocale = Locale.getDefault();
 994         checkNamedModule(caller);
 995         return getBundleImpl(baseName, targetLocale, caller, control);
 996     }
 997 
 998     /**
 999      * Gets a resource bundle using the specified base name and locale,
1000      * and the caller's class loader. Calling this method is equivalent to calling
1001      * <blockquote>
1002      * <code>getBundle(baseName, locale, this.getClass().getClassLoader())</code>,
1003      * </blockquote>
1004      * except that <code>getClassLoader()</code> is run with the security
1005      * privileges of <code>ResourceBundle</code>.
1006      * See {@link #getBundle(String, Locale, ClassLoader) getBundle}
1007      * for a complete description of the search and instantiation strategy.
1008      *
1009      * @param baseName
1010      *        the base name of the resource bundle, a fully qualified class name
1011      * @param locale
1012      *        the locale for which a resource bundle is desired
1013      * @exception NullPointerException
1014      *        if <code>baseName</code> or <code>locale</code> is <code>null</code>
1015      * @exception MissingResourceException
1016      *        if no resource bundle for the specified base name can be found
1017      * @return a resource bundle for the given base name and locale
1018      */
1019     @CallerSensitive
1020     public static final ResourceBundle getBundle(String baseName,
1021                                                  Locale locale)
1022     {
1023         Class<?> caller = Reflection.getCallerClass();
1024         return getBundleImpl(baseName, locale,
1025                              caller, getDefaultControl(caller, baseName));
1026     }
1027 
1028     /**
1029      * Gets a resource bundle using the specified base name and the default locale
1030      * on behalf of the specified module. This method is equivalent to calling
1031      * <blockquote>
1032      * <code>getBundle(baseName, Locale.getDefault(), module)</code>
1033      * </blockquote>
1034      *
1035      * <p> Resource bundles in named modules may be encapsulated.  When
1036      * the resource bundle is loaded from a provider, the caller module
1037      * must have an appropriate <i>uses</i> clause in its <i>module descriptor</i>
1038      * to declare that the module uses implementations of {@code "baseName"Provider}.
1039      * When the resource bundle is loaded from the specified module, it is
1040      * subject to the encapsulation rules specified by
1041      * {@link Module#getResourceAsStream Module.getResourceAsStream}.
1042      *
1043      * @param baseName the base name of the resource bundle,
1044      *                 a fully qualified class name
1045      * @param module   the module for which the resource bundle is searched
1046      * @throws NullPointerException
1047      *         if {@code baseName} or {@code module} is {@code null}
1048      * @throws SecurityException
1049      *         if a security manager exists and the caller is not the specified
1050      *         module and doesn't have {@code RuntimePermission("getClassLoader")}
1051      * @throws MissingResourceException
1052      *         if no resource bundle for the specified base name can be found in the
1053      *         specified module
1054      * @return a resource bundle for the given base name and the default locale
1055      * @since 9
1056      * @see ResourceBundleProvider
1057      */
1058     @CallerSensitive
1059     public static ResourceBundle getBundle(String baseName, Module module) {
1060         return getBundleFromModule(Reflection.getCallerClass(), module, baseName,
1061                                    Locale.getDefault(), Control.INSTANCE);
1062     }
1063 
1064     /**
1065      * Gets a resource bundle using the specified base name and locale
1066      * on behalf of the specified module.
1067      *
1068      * <p> Resource bundles in named modules may be encapsulated.  When
1069      * the resource bundle is loaded from a provider, the caller module
1070      * must have an appropriate <i>uses</i> clause in its <i>module descriptor</i>
1071      * to declare that the module uses implementations of {@code "baseName"Provider}.
1072      * When the resource bundle is loaded from the specified module, it is
1073      * subject to the encapsulation rules specified by
1074      * {@link Module#getResourceAsStream Module.getResourceAsStream}.
1075      *
1076      * <p>
1077      * If the given {@code module} is a named module, this method will
1078      * load the service providers for {@link java.util.spi.ResourceBundleProvider}
1079      * and also resource bundles that are local in the given module or that
1080      * are visible to the class loader of the given module (refer to the
1081      * <a href="#bundleprovider">Resource Bundles in Named Modules</a> section
1082      * for details).
1083      *
1084      * <p>
1085      * If the given {@code module} is an unnamed module, then this method is
1086      * equivalent to calling {@link #getBundle(String, Locale, ClassLoader)
1087      * getBundle(baseName, targetLocale, module.getClassLoader()} to load
1088      * resource bundles that are visible to the class loader of the given
1089      * unnamed module.
1090      *
1091      * @param baseName the base name of the resource bundle,
1092      *                 a fully qualified class name
1093      * @param targetLocale the locale for which a resource bundle is desired
1094      * @param module   the module for which the resource bundle is searched
1095      * @throws NullPointerException
1096      *         if {@code baseName}, {@code targetLocale}, or {@code module} is
1097      *         {@code null}
1098      * @throws SecurityException
1099      *         if a security manager exists and the caller is not the specified
1100      *         module and doesn't have {@code RuntimePermission("getClassLoader")}
1101      * @throws MissingResourceException
1102      *         if no resource bundle for the specified base name and locale can
1103      *         be found in the specified {@code module}
1104      * @return a resource bundle for the given base name and locale in the module
1105      * @since 9
1106      */
1107     @CallerSensitive
1108     public static ResourceBundle getBundle(String baseName, Locale targetLocale, Module module) {
1109         return getBundleFromModule(Reflection.getCallerClass(), module, baseName, targetLocale,
1110                                    Control.INSTANCE);
1111     }
1112 
1113     /**
1114      * Returns a resource bundle using the specified base name, target
1115      * locale and control, and the caller's class loader. Calling this
1116      * method is equivalent to calling
1117      * <pre>
1118      * getBundle(baseName, targetLocale, this.getClass().getClassLoader(),
1119      *           control),
1120      * </pre>
1121      * except that <code>getClassLoader()</code> is run with the security
1122      * privileges of <code>ResourceBundle</code>.  See {@link
1123      * #getBundle(String, Locale, ClassLoader, Control) getBundle} for the
1124      * complete description of the resource bundle loading process with a
1125      * <code>ResourceBundle.Control</code>.
1126      *
1127      * @param baseName
1128      *        the base name of the resource bundle, a fully qualified
1129      *        class name
1130      * @param targetLocale
1131      *        the locale for which a resource bundle is desired
1132      * @param control
1133      *        the control which gives information for the resource
1134      *        bundle loading process
1135      * @return a resource bundle for the given base name and a
1136      *         <code>Locale</code> in <code>locales</code>
1137      * @throws NullPointerException
1138      *         if <code>baseName</code>, <code>locales</code> or
1139      *         <code>control</code> is <code>null</code>
1140      * @throws MissingResourceException
1141      *         if no resource bundle for the specified base name in any
1142      *         of the <code>locales</code> can be found.
1143      * @throws IllegalArgumentException
1144      *         if the given <code>control</code> doesn't perform properly
1145      *         (e.g., <code>control.getCandidateLocales</code> returns null.)
1146      *         Note that validation of <code>control</code> is performed as
1147      *         needed.
1148      * @throws UnsupportedOperationException
1149      *         if this method is called in a named module
1150      * @since 1.6
1151      */
1152     @CallerSensitive
1153     public static final ResourceBundle getBundle(String baseName, Locale targetLocale,
1154                                                  Control control) {
1155         Class<?> caller = Reflection.getCallerClass();
1156         checkNamedModule(caller);
1157         return getBundleImpl(baseName, targetLocale, caller, control);
1158     }
1159 
1160     /**
1161      * Gets a resource bundle using the specified base name, locale, and class
1162      * loader.
1163      *
1164      * <p>This method behaves the same as calling
1165      * {@link #getBundle(String, Locale, ClassLoader, Control)} passing a
1166      * default instance of {@link Control} unless another {@link Control} is
1167      * provided with the {@link ResourceBundleControlProvider} SPI. Refer to the
1168      * description of <a href="#modify_default_behavior">modifying the default
1169      * behavior</a>.
1170      *
1171      * <p><a name="default_behavior">The following describes the default
1172      * behavior</a>.
1173      *
1174      * <p>
1175      * Resource bundles in a named module are private to that module.  If
1176      * the caller is in a named module, this method will find resource bundles
1177      * from the service providers of {@link java.util.spi.ResourceBundleProvider}
1178      * and also find resource bundles that are in the caller's module or
1179      * that are visible to the given class loader.
1180      * If the caller is in a named module and the given {@code loader} is
1181      * different than the caller's class loader, or if the caller is not in
1182      * a named module, this method will not find resource bundles from named
1183      * modules.
1184      *
1185      * <p><code>getBundle</code> uses the base name, the specified locale, and
1186      * the default locale (obtained from {@link java.util.Locale#getDefault()
1187      * Locale.getDefault}) to generate a sequence of <a
1188      * name="candidates"><em>candidate bundle names</em></a>.  If the specified
1189      * locale's language, script, country, and variant are all empty strings,
1190      * then the base name is the only candidate bundle name.  Otherwise, a list
1191      * of candidate locales is generated from the attribute values of the
1192      * specified locale (language, script, country and variant) and appended to
1193      * the base name.  Typically, this will look like the following:
1194      *
1195      * <pre>
1196      *     baseName + "_" + language + "_" + script + "_" + country + "_" + variant
1197      *     baseName + "_" + language + "_" + script + "_" + country
1198      *     baseName + "_" + language + "_" + script
1199      *     baseName + "_" + language + "_" + country + "_" + variant
1200      *     baseName + "_" + language + "_" + country
1201      *     baseName + "_" + language
1202      * </pre>
1203      *
1204      * <p>Candidate bundle names where the final component is an empty string
1205      * are omitted, along with the underscore.  For example, if country is an
1206      * empty string, the second and the fifth candidate bundle names above
1207      * would be omitted.  Also, if script is an empty string, the candidate names
1208      * including script are omitted.  For example, a locale with language "de"
1209      * and variant "JAVA" will produce candidate names with base name
1210      * "MyResource" below.
1211      *
1212      * <pre>
1213      *     MyResource_de__JAVA
1214      *     MyResource_de
1215      * </pre>
1216      *
1217      * In the case that the variant contains one or more underscores ('_'), a
1218      * sequence of bundle names generated by truncating the last underscore and
1219      * the part following it is inserted after a candidate bundle name with the
1220      * original variant.  For example, for a locale with language "en", script
1221      * "Latn, country "US" and variant "WINDOWS_VISTA", and bundle base name
1222      * "MyResource", the list of candidate bundle names below is generated:
1223      *
1224      * <pre>
1225      * MyResource_en_Latn_US_WINDOWS_VISTA
1226      * MyResource_en_Latn_US_WINDOWS
1227      * MyResource_en_Latn_US
1228      * MyResource_en_Latn
1229      * MyResource_en_US_WINDOWS_VISTA
1230      * MyResource_en_US_WINDOWS
1231      * MyResource_en_US
1232      * MyResource_en
1233      * </pre>
1234      *
1235      * <blockquote><b>Note:</b> For some <code>Locale</code>s, the list of
1236      * candidate bundle names contains extra names, or the order of bundle names
1237      * is slightly modified.  See the description of the default implementation
1238      * of {@link Control#getCandidateLocales(String, Locale)
1239      * getCandidateLocales} for details.</blockquote>
1240      *
1241      * <p><code>getBundle</code> then iterates over the candidate bundle names
1242      * to find the first one for which it can <em>instantiate</em> an actual
1243      * resource bundle. It uses the default controls' {@link Control#getFormats
1244      * getFormats} method, which generates two bundle names for each generated
1245      * name, the first a class name and the second a properties file name. For
1246      * each candidate bundle name, it attempts to create a resource bundle:
1247      *
1248      * <ul><li>First, it attempts to load a class using the generated class name.
1249      * If such a class can be found and loaded using the specified class
1250      * loader, is assignment compatible with ResourceBundle, is accessible from
1251      * ResourceBundle, and can be instantiated, <code>getBundle</code> creates a
1252      * new instance of this class and uses it as the <em>result resource
1253      * bundle</em>.
1254      *
1255      * <li>Otherwise, <code>getBundle</code> attempts to locate a property
1256      * resource file using the generated properties file name.  It generates a
1257      * path name from the candidate bundle name by replacing all "." characters
1258      * with "/" and appending the string ".properties".  It attempts to find a
1259      * "resource" with this name using {@link
1260      * java.lang.ClassLoader#getResource(java.lang.String)
1261      * ClassLoader.getResource}.  (Note that a "resource" in the sense of
1262      * <code>getResource</code> has nothing to do with the contents of a
1263      * resource bundle, it is just a container of data, such as a file.)  If it
1264      * finds a "resource", it attempts to create a new {@link
1265      * PropertyResourceBundle} instance from its contents.  If successful, this
1266      * instance becomes the <em>result resource bundle</em>.  </ul>
1267      *
1268      * <p>This continues until a result resource bundle is instantiated or the
1269      * list of candidate bundle names is exhausted.  If no matching resource
1270      * bundle is found, the default control's {@link Control#getFallbackLocale
1271      * getFallbackLocale} method is called, which returns the current default
1272      * locale.  A new sequence of candidate locale names is generated using this
1273      * locale and searched again, as above.
1274      *
1275      * <p>If still no result bundle is found, the base name alone is looked up. If
1276      * this still fails, a <code>MissingResourceException</code> is thrown.
1277      *
1278      * <p><a name="parent_chain"> Once a result resource bundle has been found,
1279      * its <em>parent chain</em> is instantiated</a>.  If the result bundle already
1280      * has a parent (perhaps because it was returned from a cache) the chain is
1281      * complete.
1282      *
1283      * <p>Otherwise, <code>getBundle</code> examines the remainder of the
1284      * candidate locale list that was used during the pass that generated the
1285      * result resource bundle.  (As before, candidate bundle names where the
1286      * final component is an empty string are omitted.)  When it comes to the
1287      * end of the candidate list, it tries the plain bundle name.  With each of the
1288      * candidate bundle names it attempts to instantiate a resource bundle (first
1289      * looking for a class and then a properties file, as described above).
1290      *
1291      * <p>Whenever it succeeds, it calls the previously instantiated resource
1292      * bundle's {@link #setParent(java.util.ResourceBundle) setParent} method
1293      * with the new resource bundle.  This continues until the list of names
1294      * is exhausted or the current bundle already has a non-null parent.
1295      *
1296      * <p>Once the parent chain is complete, the bundle is returned.
1297      *
1298      * <p><b>Note:</b> <code>getBundle</code> caches instantiated resource
1299      * bundles and might return the same resource bundle instance multiple times.
1300      *
1301      * <p><b>Note:</b>The <code>baseName</code> argument should be a fully
1302      * qualified class name. However, for compatibility with earlier versions,
1303      * Sun's Java SE Runtime Environments do not verify this, and so it is
1304      * possible to access <code>PropertyResourceBundle</code>s by specifying a
1305      * path name (using "/") instead of a fully qualified class name (using
1306      * ".").
1307      *
1308      * <p><a name="default_behavior_example">
1309      * <strong>Example:</strong></a>
1310      * <p>
1311      * The following class and property files are provided:
1312      * <pre>
1313      *     MyResources.class
1314      *     MyResources.properties
1315      *     MyResources_fr.properties
1316      *     MyResources_fr_CH.class
1317      *     MyResources_fr_CH.properties
1318      *     MyResources_en.properties
1319      *     MyResources_es_ES.class
1320      * </pre>
1321      *
1322      * The contents of all files are valid (that is, public non-abstract
1323      * subclasses of <code>ResourceBundle</code> for the ".class" files,
1324      * syntactically correct ".properties" files).  The default locale is
1325      * <code>Locale("en", "GB")</code>.
1326      *
1327      * <p>Calling <code>getBundle</code> with the locale arguments below will
1328      * instantiate resource bundles as follows:
1329      *
1330      * <table summary="getBundle() locale to resource bundle mapping">
1331      * <tr><td>Locale("fr", "CH")</td><td>MyResources_fr_CH.class, parent MyResources_fr.properties, parent MyResources.class</td></tr>
1332      * <tr><td>Locale("fr", "FR")</td><td>MyResources_fr.properties, parent MyResources.class</td></tr>
1333      * <tr><td>Locale("de", "DE")</td><td>MyResources_en.properties, parent MyResources.class</td></tr>
1334      * <tr><td>Locale("en", "US")</td><td>MyResources_en.properties, parent MyResources.class</td></tr>
1335      * <tr><td>Locale("es", "ES")</td><td>MyResources_es_ES.class, parent MyResources.class</td></tr>
1336      * </table>
1337      *
1338      * <p>The file MyResources_fr_CH.properties is never used because it is
1339      * hidden by the MyResources_fr_CH.class. Likewise, MyResources.properties
1340      * is also hidden by MyResources.class.
1341      *
1342      * @apiNote If the caller module is a named module and the given
1343      * {@code loader} is the caller module's class loader, this method is
1344      * equivalent to {@code getBundle(baseName, locale)}; otherwise, it will not
1345      * find resource bundles from named modules.
1346      * Use {@link #getBundle(String, Locale, Module)} to load resource bundles
1347      * on behalf on a specific module instead.
1348      *
1349      * @param baseName the base name of the resource bundle, a fully qualified class name
1350      * @param locale the locale for which a resource bundle is desired
1351      * @param loader the class loader from which to load the resource bundle
1352      * @return a resource bundle for the given base name and locale
1353      * @exception java.lang.NullPointerException
1354      *        if <code>baseName</code>, <code>locale</code>, or <code>loader</code> is <code>null</code>
1355      * @exception MissingResourceException
1356      *        if no resource bundle for the specified base name can be found
1357      * @since 1.2
1358      */
1359     @CallerSensitive
1360     public static ResourceBundle getBundle(String baseName, Locale locale,
1361                                            ClassLoader loader)
1362     {
1363         if (loader == null) {
1364             throw new NullPointerException();
1365         }
1366         Class<?> caller = Reflection.getCallerClass();
1367         return getBundleImpl(baseName, locale, caller, loader, getDefaultControl(caller, baseName));
1368     }
1369 
1370     /**
1371      * Returns a resource bundle using the specified base name, target
1372      * locale, class loader and control. Unlike the {@linkplain
1373      * #getBundle(String, Locale, ClassLoader) <code>getBundle</code>
1374      * factory methods with no <code>control</code> argument}, the given
1375      * <code>control</code> specifies how to locate and instantiate resource
1376      * bundles. Conceptually, the bundle loading process with the given
1377      * <code>control</code> is performed in the following steps.
1378      *
1379      * <ol>
1380      * <li>This factory method looks up the resource bundle in the cache for
1381      * the specified <code>baseName</code>, <code>targetLocale</code> and
1382      * <code>loader</code>.  If the requested resource bundle instance is
1383      * found in the cache and the time-to-live periods of the instance and
1384      * all of its parent instances have not expired, the instance is returned
1385      * to the caller. Otherwise, this factory method proceeds with the
1386      * loading process below.</li>
1387      *
1388      * <li>The {@link ResourceBundle.Control#getFormats(String)
1389      * control.getFormats} method is called to get resource bundle formats
1390      * to produce bundle or resource names. The strings
1391      * <code>"java.class"</code> and <code>"java.properties"</code>
1392      * designate class-based and {@linkplain PropertyResourceBundle
1393      * property}-based resource bundles, respectively. Other strings
1394      * starting with <code>"java."</code> are reserved for future extensions
1395      * and must not be used for application-defined formats. Other strings
1396      * designate application-defined formats.</li>
1397      *
1398      * <li>The {@link ResourceBundle.Control#getCandidateLocales(String,
1399      * Locale) control.getCandidateLocales} method is called with the target
1400      * locale to get a list of <em>candidate <code>Locale</code>s</em> for
1401      * which resource bundles are searched.</li>
1402      *
1403      * <li>The {@link ResourceBundle.Control#newBundle(String, Locale,
1404      * String, ClassLoader, boolean) control.newBundle} method is called to
1405      * instantiate a <code>ResourceBundle</code> for the base bundle name, a
1406      * candidate locale, and a format. (Refer to the note on the cache
1407      * lookup below.) This step is iterated over all combinations of the
1408      * candidate locales and formats until the <code>newBundle</code> method
1409      * returns a <code>ResourceBundle</code> instance or the iteration has
1410      * used up all the combinations. For example, if the candidate locales
1411      * are <code>Locale("de", "DE")</code>, <code>Locale("de")</code> and
1412      * <code>Locale("")</code> and the formats are <code>"java.class"</code>
1413      * and <code>"java.properties"</code>, then the following is the
1414      * sequence of locale-format combinations to be used to call
1415      * <code>control.newBundle</code>.
1416      *
1417      * <table style="width: 50%; text-align: left; margin-left: 40px;"
1418      *  border="0" cellpadding="2" cellspacing="2" summary="locale-format combinations for newBundle">
1419      * <tbody>
1420      * <tr>
1421      * <td
1422      * style="vertical-align: top; text-align: left; font-weight: bold; width: 50%;"><code>Locale</code><br>
1423      * </td>
1424      * <td
1425      * style="vertical-align: top; text-align: left; font-weight: bold; width: 50%;"><code>format</code><br>
1426      * </td>
1427      * </tr>
1428      * <tr>
1429      * <td style="vertical-align: top; width: 50%;"><code>Locale("de", "DE")</code><br>
1430      * </td>
1431      * <td style="vertical-align: top; width: 50%;"><code>java.class</code><br>
1432      * </td>
1433      * </tr>
1434      * <tr>
1435      * <td style="vertical-align: top; width: 50%;"><code>Locale("de", "DE")</code></td>
1436      * <td style="vertical-align: top; width: 50%;"><code>java.properties</code><br>
1437      * </td>
1438      * </tr>
1439      * <tr>
1440      * <td style="vertical-align: top; width: 50%;"><code>Locale("de")</code></td>
1441      * <td style="vertical-align: top; width: 50%;"><code>java.class</code></td>
1442      * </tr>
1443      * <tr>
1444      * <td style="vertical-align: top; width: 50%;"><code>Locale("de")</code></td>
1445      * <td style="vertical-align: top; width: 50%;"><code>java.properties</code></td>
1446      * </tr>
1447      * <tr>
1448      * <td style="vertical-align: top; width: 50%;"><code>Locale("")</code><br>
1449      * </td>
1450      * <td style="vertical-align: top; width: 50%;"><code>java.class</code></td>
1451      * </tr>
1452      * <tr>
1453      * <td style="vertical-align: top; width: 50%;"><code>Locale("")</code></td>
1454      * <td style="vertical-align: top; width: 50%;"><code>java.properties</code></td>
1455      * </tr>
1456      * </tbody>
1457      * </table>
1458      * </li>
1459      *
1460      * <li>If the previous step has found no resource bundle, proceed to
1461      * Step 6. If a bundle has been found that is a base bundle (a bundle
1462      * for <code>Locale("")</code>), and the candidate locale list only contained
1463      * <code>Locale("")</code>, return the bundle to the caller. If a bundle
1464      * has been found that is a base bundle, but the candidate locale list
1465      * contained locales other than Locale(""), put the bundle on hold and
1466      * proceed to Step 6. If a bundle has been found that is not a base
1467      * bundle, proceed to Step 7.</li>
1468      *
1469      * <li>The {@link ResourceBundle.Control#getFallbackLocale(String,
1470      * Locale) control.getFallbackLocale} method is called to get a fallback
1471      * locale (alternative to the current target locale) to try further
1472      * finding a resource bundle. If the method returns a non-null locale,
1473      * it becomes the next target locale and the loading process starts over
1474      * from Step 3. Otherwise, if a base bundle was found and put on hold in
1475      * a previous Step 5, it is returned to the caller now. Otherwise, a
1476      * MissingResourceException is thrown.</li>
1477      *
1478      * <li>At this point, we have found a resource bundle that's not the
1479      * base bundle. If this bundle set its parent during its instantiation,
1480      * it is returned to the caller. Otherwise, its <a
1481      * href="./ResourceBundle.html#parent_chain">parent chain</a> is
1482      * instantiated based on the list of candidate locales from which it was
1483      * found. Finally, the bundle is returned to the caller.</li>
1484      * </ol>
1485      *
1486      * <p>During the resource bundle loading process above, this factory
1487      * method looks up the cache before calling the {@link
1488      * Control#newBundle(String, Locale, String, ClassLoader, boolean)
1489      * control.newBundle} method.  If the time-to-live period of the
1490      * resource bundle found in the cache has expired, the factory method
1491      * calls the {@link ResourceBundle.Control#needsReload(String, Locale,
1492      * String, ClassLoader, ResourceBundle, long) control.needsReload}
1493      * method to determine whether the resource bundle needs to be reloaded.
1494      * If reloading is required, the factory method calls
1495      * <code>control.newBundle</code> to reload the resource bundle.  If
1496      * <code>control.newBundle</code> returns <code>null</code>, the factory
1497      * method puts a dummy resource bundle in the cache as a mark of
1498      * nonexistent resource bundles in order to avoid lookup overhead for
1499      * subsequent requests. Such dummy resource bundles are under the same
1500      * expiration control as specified by <code>control</code>.
1501      *
1502      * <p>All resource bundles loaded are cached by default. Refer to
1503      * {@link Control#getTimeToLive(String,Locale)
1504      * control.getTimeToLive} for details.
1505      *
1506      * <p>The following is an example of the bundle loading process with the
1507      * default <code>ResourceBundle.Control</code> implementation.
1508      *
1509      * <p>Conditions:
1510      * <ul>
1511      * <li>Base bundle name: <code>foo.bar.Messages</code>
1512      * <li>Requested <code>Locale</code>: {@link Locale#ITALY}</li>
1513      * <li>Default <code>Locale</code>: {@link Locale#FRENCH}</li>
1514      * <li>Available resource bundles:
1515      * <code>foo/bar/Messages_fr.properties</code> and
1516      * <code>foo/bar/Messages.properties</code></li>
1517      * </ul>
1518      *
1519      * <p>First, <code>getBundle</code> tries loading a resource bundle in
1520      * the following sequence.
1521      *
1522      * <ul>
1523      * <li>class <code>foo.bar.Messages_it_IT</code>
1524      * <li>file <code>foo/bar/Messages_it_IT.properties</code>
1525      * <li>class <code>foo.bar.Messages_it</code></li>
1526      * <li>file <code>foo/bar/Messages_it.properties</code></li>
1527      * <li>class <code>foo.bar.Messages</code></li>
1528      * <li>file <code>foo/bar/Messages.properties</code></li>
1529      * </ul>
1530      *
1531      * <p>At this point, <code>getBundle</code> finds
1532      * <code>foo/bar/Messages.properties</code>, which is put on hold
1533      * because it's the base bundle.  <code>getBundle</code> calls {@link
1534      * Control#getFallbackLocale(String, Locale)
1535      * control.getFallbackLocale("foo.bar.Messages", Locale.ITALY)} which
1536      * returns <code>Locale.FRENCH</code>. Next, <code>getBundle</code>
1537      * tries loading a bundle in the following sequence.
1538      *
1539      * <ul>
1540      * <li>class <code>foo.bar.Messages_fr</code></li>
1541      * <li>file <code>foo/bar/Messages_fr.properties</code></li>
1542      * <li>class <code>foo.bar.Messages</code></li>
1543      * <li>file <code>foo/bar/Messages.properties</code></li>
1544      * </ul>
1545      *
1546      * <p><code>getBundle</code> finds
1547      * <code>foo/bar/Messages_fr.properties</code> and creates a
1548      * <code>ResourceBundle</code> instance. Then, <code>getBundle</code>
1549      * sets up its parent chain from the list of the candidate locales.  Only
1550      * <code>foo/bar/Messages.properties</code> is found in the list and
1551      * <code>getBundle</code> creates a <code>ResourceBundle</code> instance
1552      * that becomes the parent of the instance for
1553      * <code>foo/bar/Messages_fr.properties</code>.
1554      *
1555      * @param baseName
1556      *        the base name of the resource bundle, a fully qualified
1557      *        class name
1558      * @param targetLocale
1559      *        the locale for which a resource bundle is desired
1560      * @param loader
1561      *        the class loader from which to load the resource bundle
1562      * @param control
1563      *        the control which gives information for the resource
1564      *        bundle loading process
1565      * @return a resource bundle for the given base name and locale
1566      * @throws NullPointerException
1567      *         if <code>baseName</code>, <code>targetLocale</code>,
1568      *         <code>loader</code>, or <code>control</code> is
1569      *         <code>null</code>
1570      * @throws MissingResourceException
1571      *         if no resource bundle for the specified base name can be found
1572      * @throws IllegalArgumentException
1573      *         if the given <code>control</code> doesn't perform properly
1574      *         (e.g., <code>control.getCandidateLocales</code> returns null.)
1575      *         Note that validation of <code>control</code> is performed as
1576      *         needed.
1577      * @throws UnsupportedOperationException
1578      *         if this method is called in a named module
1579      * @since 1.6
1580      */
1581     @CallerSensitive
1582     public static ResourceBundle getBundle(String baseName, Locale targetLocale,
1583                                            ClassLoader loader, Control control) {
1584         if (loader == null || control == null) {
1585             throw new NullPointerException();
1586         }
1587         Class<?> caller = Reflection.getCallerClass();
1588         checkNamedModule(caller);
1589         return getBundleImpl(baseName, targetLocale, caller, loader, control);
1590     }
1591 
1592     private static Control getDefaultControl(Class<?> caller, String baseName) {
1593         if (providers != null && !caller.getModule().isNamed()) {
1594             for (ResourceBundleControlProvider provider : providers) {
1595                 Control control = provider.getControl(baseName);
1596                 if (control != null) {
1597                     return control;
1598                 }
1599             }
1600         }
1601         return Control.INSTANCE;
1602     }
1603 
1604     private static void checkNamedModule(Class<?> caller) {
1605         if (caller.getModule().isNamed()) {
1606             throw new UnsupportedOperationException(
1607                     "ResourceBundle.Control not supported in named modules");
1608         }
1609     }
1610 
1611     private static ResourceBundle getBundleImpl(String baseName,
1612                                                 Locale locale,
1613                                                 Class<?> caller,
1614                                                 Control control) {
1615         return getBundleImpl(baseName, locale, caller, getLoader(caller), control);
1616     }
1617 
1618     /**
1619      * This method will find resource bundles using the legacy mechanism
1620      * if the caller is unnamed module or the given class loader is
1621      * not the class loader of the caller module getting the resource
1622      * bundle, i.e. find the class that is visible to the class loader
1623      * and properties from unnamed module.
1624      *
1625      * The module-aware resource bundle lookup mechanism will load
1626      * the service providers using the service loader mechanism
1627      * as well as properties local in the caller module.
1628      */
1629     private static ResourceBundle getBundleImpl(String baseName,
1630                                                 Locale locale,
1631                                                 Class<?> caller,
1632                                                 ClassLoader loader,
1633                                                 Control control) {
1634         if (caller != null && caller.getModule().isNamed()) {
1635             Module module = caller.getModule();
1636             ClassLoader ml = getLoader(module);
1637             // get resource bundles for a named module only
1638             // if loader is the module's class loader
1639             if (loader == ml || (ml == null && loader == RBClassLoader.INSTANCE)) {
1640                 return getBundleImpl(module, module, loader, baseName, locale, control);
1641             }
1642         }
1643         // find resource bundles from unnamed module
1644         Module unnamedModule = loader != null
1645             ? loader.getUnnamedModule()
1646             : ClassLoader.getSystemClassLoader().getUnnamedModule();
1647 
1648         if (caller == null) {
1649             throw new InternalError("null caller");
1650         }
1651 
1652         Module callerModule = caller.getModule();
1653         return getBundleImpl(callerModule, unnamedModule, loader, baseName, locale, control);
1654     }
1655 
1656     private static ResourceBundle getBundleFromModule(Class<?> caller,
1657                                                       Module module,
1658                                                       String baseName,
1659                                                       Locale locale,
1660                                                       Control control) {
1661         Objects.requireNonNull(module);
1662         Module callerModule = caller.getModule();
1663         if (callerModule != module) {
1664             SecurityManager sm = System.getSecurityManager();
1665             if (sm != null) {
1666                 sm.checkPermission(GET_CLASSLOADER_PERMISSION);
1667             }
1668         }
1669         return getBundleImpl(callerModule, module, getLoader(module), baseName, locale, control);
1670     }
1671 
1672     private static ResourceBundle getBundleImpl(Module callerModule,
1673                                                 Module module,
1674                                                 ClassLoader loader,
1675                                                 String baseName,
1676                                                 Locale locale,
1677                                                 Control control) {
1678         if (locale == null || control == null) {
1679             throw new NullPointerException();
1680         }
1681 
1682         // We create a CacheKey here for use by this call. The base name
1683         // loader, and module will never change during the bundle loading
1684         // process. We have to make sure that the locale is set before
1685         // using it as a cache key.
1686         CacheKey cacheKey = new CacheKey(baseName, locale, loader, module, callerModule);
1687         ResourceBundle bundle = null;
1688 
1689         // Quick lookup of the cache.
1690         BundleReference bundleRef = cacheList.get(cacheKey);
1691         if (bundleRef != null) {
1692             bundle = bundleRef.get();
1693             bundleRef = null;
1694         }
1695 
1696         // If this bundle and all of its parents are valid (not expired),
1697         // then return this bundle. If any of the bundles is expired, we
1698         // don't call control.needsReload here but instead drop into the
1699         // complete loading process below.
1700         if (isValidBundle(bundle) && hasValidParentChain(bundle)) {
1701             return bundle;
1702         }
1703 
1704         // No valid bundle was found in the cache, so we need to load the
1705         // resource bundle and its parents.
1706 
1707         boolean isKnownControl = (control == Control.INSTANCE) ||
1708                                    (control instanceof SingleFormatControl);
1709         List<String> formats = control.getFormats(baseName);
1710         if (!isKnownControl && !checkList(formats)) {
1711             throw new IllegalArgumentException("Invalid Control: getFormats");
1712         }
1713 
1714         ResourceBundle baseBundle = null;
1715         for (Locale targetLocale = locale;
1716              targetLocale != null;
1717              targetLocale = control.getFallbackLocale(baseName, targetLocale)) {
1718             List<Locale> candidateLocales = control.getCandidateLocales(baseName, targetLocale);
1719             if (!isKnownControl && !checkList(candidateLocales)) {
1720                 throw new IllegalArgumentException("Invalid Control: getCandidateLocales");
1721             }
1722 
1723             bundle = findBundle(callerModule, module, cacheKey,
1724                                 candidateLocales, formats, 0, control, baseBundle);
1725 
1726             // If the loaded bundle is the base bundle and exactly for the
1727             // requested locale or the only candidate locale, then take the
1728             // bundle as the resulting one. If the loaded bundle is the base
1729             // bundle, it's put on hold until we finish processing all
1730             // fallback locales.
1731             if (isValidBundle(bundle)) {
1732                 boolean isBaseBundle = Locale.ROOT.equals(bundle.locale);
1733                 if (!isBaseBundle || bundle.locale.equals(locale)
1734                     || (candidateLocales.size() == 1
1735                         && bundle.locale.equals(candidateLocales.get(0)))) {
1736                     break;
1737                 }
1738 
1739                 // If the base bundle has been loaded, keep the reference in
1740                 // baseBundle so that we can avoid any redundant loading in case
1741                 // the control specify not to cache bundles.
1742                 if (isBaseBundle && baseBundle == null) {
1743                     baseBundle = bundle;
1744                 }
1745             }
1746         }
1747 
1748         if (bundle == null) {
1749             if (baseBundle == null) {
1750                 throwMissingResourceException(baseName, locale, cacheKey.getCause());
1751             }
1752             bundle = baseBundle;
1753         }
1754 
1755         return bundle;
1756     }
1757 
1758     /**
1759      * Checks if the given <code>List</code> is not null, not empty,
1760      * not having null in its elements.
1761      */
1762     private static boolean checkList(List<?> a) {
1763         boolean valid = (a != null && !a.isEmpty());
1764         if (valid) {
1765             int size = a.size();
1766             for (int i = 0; valid && i < size; i++) {
1767                 valid = (a.get(i) != null);
1768             }
1769         }
1770         return valid;
1771     }
1772 
1773     private static ResourceBundle findBundle(Module callerModule,
1774                                              Module module,
1775                                              CacheKey cacheKey,
1776                                              List<Locale> candidateLocales,
1777                                              List<String> formats,
1778                                              int index,
1779                                              Control control,
1780                                              ResourceBundle baseBundle) {
1781         Locale targetLocale = candidateLocales.get(index);
1782         ResourceBundle parent = null;
1783         if (index != candidateLocales.size() - 1) {
1784             parent = findBundle(callerModule, module, cacheKey,
1785                                 candidateLocales, formats, index + 1,
1786                                 control, baseBundle);
1787         } else if (baseBundle != null && Locale.ROOT.equals(targetLocale)) {
1788             return baseBundle;
1789         }
1790 
1791         // Before we do the real loading work, see whether we need to
1792         // do some housekeeping: If references to class loaders or
1793         // resource bundles have been nulled out, remove all related
1794         // information from the cache.
1795         Object ref;
1796         while ((ref = referenceQueue.poll()) != null) {
1797             cacheList.remove(((CacheKeyReference)ref).getCacheKey());
1798         }
1799 
1800         // flag indicating the resource bundle has expired in the cache
1801         boolean expiredBundle = false;
1802 
1803         // First, look up the cache to see if it's in the cache, without
1804         // attempting to load bundle.
1805         cacheKey.setLocale(targetLocale);
1806         ResourceBundle bundle = findBundleInCache(cacheKey, control);
1807         if (isValidBundle(bundle)) {
1808             expiredBundle = bundle.expired;
1809             if (!expiredBundle) {
1810                 // If its parent is the one asked for by the candidate
1811                 // locales (the runtime lookup path), we can take the cached
1812                 // one. (If it's not identical, then we'd have to check the
1813                 // parent's parents to be consistent with what's been
1814                 // requested.)
1815                 if (bundle.parent == parent) {
1816                     return bundle;
1817                 }
1818                 // Otherwise, remove the cached one since we can't keep
1819                 // the same bundles having different parents.
1820                 BundleReference bundleRef = cacheList.get(cacheKey);
1821                 if (bundleRef != null && bundleRef.get() == bundle) {
1822                     cacheList.remove(cacheKey, bundleRef);
1823                 }
1824             }
1825         }
1826 
1827         if (bundle != NONEXISTENT_BUNDLE) {
1828             CacheKey constKey = (CacheKey) cacheKey.clone();
1829             trace("findBundle: %d %s %s formats: %s%n", index, candidateLocales, cacheKey, formats);
1830             try {
1831                 if (module.isNamed()) {
1832                     bundle = loadBundle(cacheKey, formats, control, module, callerModule);
1833                 } else {
1834                     bundle = loadBundle(cacheKey, formats, control, expiredBundle);
1835                 }
1836                 if (bundle != null) {
1837                     if (bundle.parent == null) {
1838                         bundle.setParent(parent);
1839                     }
1840                     bundle.locale = targetLocale;
1841                     bundle = putBundleInCache(cacheKey, bundle, control);
1842                     return bundle;
1843                 }
1844 
1845                 // Put NONEXISTENT_BUNDLE in the cache as a mark that there's no bundle
1846                 // instance for the locale.
1847                 putBundleInCache(cacheKey, NONEXISTENT_BUNDLE, control);
1848             } finally {
1849                 if (constKey.getCause() instanceof InterruptedException) {
1850                     Thread.currentThread().interrupt();
1851                 }
1852             }
1853         }
1854         return parent;
1855     }
1856 
1857     private static final String UNKNOWN_FORMAT = "";
1858 
1859 
1860     /*
1861      * Loads a ResourceBundle in named modules
1862      */
1863     private static ResourceBundle loadBundle(CacheKey cacheKey,
1864                                              List<String> formats,
1865                                              Control control,
1866                                              Module module,
1867                                              Module callerModule) {
1868         String baseName = cacheKey.getName();
1869         Locale targetLocale = cacheKey.getLocale();
1870 
1871         ResourceBundle bundle = null;
1872         if (cacheKey.hasProviders()) {
1873             if (callerModule == module) {
1874                 bundle = loadBundleFromProviders(baseName,
1875                                                  targetLocale,
1876                                                  cacheKey.getProviders(),
1877                                                  cacheKey);
1878             } else {
1879                 // load from provider if the caller module has access to the
1880                 // service type and also declares `uses`
1881                 ClassLoader loader = getLoader(module);
1882                 Class<ResourceBundleProvider> svc =
1883                     getResourceBundleProviderType(baseName, loader);
1884                 if (svc != null
1885                         && Reflection.verifyModuleAccess(callerModule, svc)
1886                         && callerModule.canUse(svc)) {
1887                     bundle = loadBundleFromProviders(baseName,
1888                                                      targetLocale,
1889                                                      cacheKey.getProviders(),
1890                                                      cacheKey);
1891                 }
1892             }
1893 
1894             if (bundle != null) {
1895                 cacheKey.setFormat(UNKNOWN_FORMAT);
1896             }
1897         }
1898 
1899         // If none of providers returned a bundle and the caller has no provider,
1900         // look up module-local bundles or from the class path
1901         if (bundle == null && !cacheKey.callerHasProvider()) {
1902             for (String format : formats) {
1903                 try {
1904                     switch (format) {
1905                     case "java.class":
1906                         bundle = ResourceBundleProviderHelper
1907                             .loadResourceBundle(callerModule, module, baseName, targetLocale);
1908 
1909                         break;
1910                     case "java.properties":
1911                         bundle = ResourceBundleProviderHelper
1912                             .loadPropertyResourceBundle(callerModule, module, baseName, targetLocale);
1913                         break;
1914                     default:
1915                         throw new InternalError("unexpected format: " + format);
1916                     }
1917 
1918                     if (bundle != null) {
1919                         cacheKey.setFormat(format);
1920                         break;
1921                     }
1922                 } catch (Exception e) {
1923                     cacheKey.setCause(e);
1924                 }
1925             }
1926         }
1927         return bundle;
1928     }
1929 
1930     /**
1931      * Returns a ServiceLoader that will find providers that are bound to
1932      * a given named module.
1933      */
1934     private static ServiceLoader<ResourceBundleProvider> getServiceLoader(Module module,
1935                                                                           String baseName)
1936     {
1937         if (!module.isNamed()) {
1938             return null;
1939         }
1940 
1941         ClassLoader loader = getLoader(module);
1942         Class<ResourceBundleProvider> service =
1943                 getResourceBundleProviderType(baseName, loader);
1944         if (service != null && Reflection.verifyModuleAccess(module, service)) {
1945             try {
1946                 // locate providers that are visible to the class loader
1947                 // ServiceConfigurationError will be thrown if the module
1948                 // does not declare `uses` the service type
1949                 return ServiceLoader.load(service, loader, module);
1950             } catch (ServiceConfigurationError e) {
1951                 // "uses" not declared
1952                 return null;
1953             }
1954         }
1955         return null;
1956     }
1957 
1958     /**
1959      * Returns the service type of the given baseName that is visible
1960      * to the given class loader
1961      */
1962     private static Class<ResourceBundleProvider>
1963             getResourceBundleProviderType(String baseName, ClassLoader loader)
1964     {
1965         // Look up <baseName> + "Provider"
1966         String providerName = baseName + "Provider";
1967         // Use the class loader of the getBundle caller so that the caller's
1968         // visibility of the provider type is checked.
1969         return AccessController.doPrivileged(
1970             new PrivilegedAction<>() {
1971                 @Override
1972                 public Class<ResourceBundleProvider> run() {
1973                     try {
1974                         Class<?> c = Class.forName(providerName, false, loader);
1975                         if (ResourceBundleProvider.class.isAssignableFrom(c)) {
1976                             @SuppressWarnings("unchecked")
1977                             Class<ResourceBundleProvider> s = (Class<ResourceBundleProvider>) c;
1978                             return s;
1979                         }
1980                     } catch (ClassNotFoundException e) {}
1981                     return null;
1982                 }
1983             });
1984     }
1985 
1986     /**
1987      * Loads ResourceBundle from service providers.
1988      */
1989     private static ResourceBundle loadBundleFromProviders(String baseName,
1990                                                           Locale locale,
1991                                                           ServiceLoader<ResourceBundleProvider> providers,
1992                                                           CacheKey cacheKey)
1993     {
1994         if (providers == null) return null;
1995 
1996         return AccessController.doPrivileged(
1997                 new PrivilegedAction<>() {
1998                     public ResourceBundle run() {
1999                         for (Iterator<ResourceBundleProvider> itr = providers.iterator(); itr.hasNext(); ) {
2000                             try {
2001                                 ResourceBundleProvider provider = itr.next();
2002                                 if (cacheKey != null && cacheKey.callerHasProvider == null
2003                                         && cacheKey.getModule() == provider.getClass().getModule()) {
2004                                     cacheKey.callerHasProvider = Boolean.TRUE;
2005                                 }
2006                                 ResourceBundle bundle = provider.getBundle(baseName, locale);
2007                                 trace("provider %s %s locale: %s bundle: %s%n", provider, baseName, locale, bundle);
2008                                 if (bundle != null) {
2009                                     return bundle;
2010                                 }
2011                             } catch (ServiceConfigurationError | SecurityException e) {
2012                                 if (cacheKey != null) {
2013                                     cacheKey.setCause(e);
2014                                 }
2015                             }
2016                         }
2017                         if (cacheKey != null && cacheKey.callerHasProvider == null) {
2018                             cacheKey.callerHasProvider = Boolean.FALSE;
2019                         }
2020                         return null;
2021                     }
2022                 });
2023 
2024     }
2025 
2026     /*
2027      * Legacy mechanism to load resource bundles
2028      */
2029     private static ResourceBundle loadBundle(CacheKey cacheKey,
2030                                              List<String> formats,
2031                                              Control control,
2032                                              boolean reload) {
2033 
2034         // Here we actually load the bundle in the order of formats
2035         // specified by the getFormats() value.
2036         Locale targetLocale = cacheKey.getLocale();
2037 
2038         ResourceBundle bundle = null;
2039         for (String format : formats) {
2040             try {
2041                 // ResourceBundle.Control.newBundle may be overridden
2042                 bundle = control.newBundle(cacheKey.getName(), targetLocale, format,
2043                                            cacheKey.getLoader(), reload);
2044             } catch (LinkageError | Exception error) {
2045                 // We need to handle the LinkageError case due to
2046                 // inconsistent case-sensitivity in ClassLoader.
2047                 // See 6572242 for details.
2048                 cacheKey.setCause(error);
2049             }
2050             if (bundle != null) {
2051                 // Set the format in the cache key so that it can be
2052                 // used when calling needsReload later.
2053                 cacheKey.setFormat(format);
2054                 bundle.name = cacheKey.getName();
2055                 bundle.locale = targetLocale;
2056                 // Bundle provider might reuse instances. So we should make
2057                 // sure to clear the expired flag here.
2058                 bundle.expired = false;
2059                 break;
2060             }
2061         }
2062 
2063         return bundle;
2064     }
2065 
2066     private static boolean isValidBundle(ResourceBundle bundle) {
2067         return bundle != null && bundle != NONEXISTENT_BUNDLE;
2068     }
2069 
2070     /**
2071      * Determines whether any of resource bundles in the parent chain,
2072      * including the leaf, have expired.
2073      */
2074     private static boolean hasValidParentChain(ResourceBundle bundle) {
2075         long now = System.currentTimeMillis();
2076         while (bundle != null) {
2077             if (bundle.expired) {
2078                 return false;
2079             }
2080             CacheKey key = bundle.cacheKey;
2081             if (key != null) {
2082                 long expirationTime = key.expirationTime;
2083                 if (expirationTime >= 0 && expirationTime <= now) {
2084                     return false;
2085                 }
2086             }
2087             bundle = bundle.parent;
2088         }
2089         return true;
2090     }
2091 
2092     /**
2093      * Throw a MissingResourceException with proper message
2094      */
2095     private static void throwMissingResourceException(String baseName,
2096                                                       Locale locale,
2097                                                       Throwable cause) {
2098         // If the cause is a MissingResourceException, avoid creating
2099         // a long chain. (6355009)
2100         if (cause instanceof MissingResourceException) {
2101             cause = null;
2102         }
2103         throw new MissingResourceException("Can't find bundle for base name "
2104                                            + baseName + ", locale " + locale,
2105                                            baseName + "_" + locale, // className
2106                                            "",                      // key
2107                                            cause);
2108     }
2109 
2110     /**
2111      * Finds a bundle in the cache. Any expired bundles are marked as
2112      * `expired' and removed from the cache upon return.
2113      *
2114      * @param cacheKey the key to look up the cache
2115      * @param control the Control to be used for the expiration control
2116      * @return the cached bundle, or null if the bundle is not found in the
2117      * cache or its parent has expired. <code>bundle.expire</code> is true
2118      * upon return if the bundle in the cache has expired.
2119      */
2120     private static ResourceBundle findBundleInCache(CacheKey cacheKey,
2121                                                     Control control) {
2122         BundleReference bundleRef = cacheList.get(cacheKey);
2123         if (bundleRef == null) {
2124             return null;
2125         }
2126         ResourceBundle bundle = bundleRef.get();
2127         if (bundle == null) {
2128             return null;
2129         }
2130         ResourceBundle p = bundle.parent;
2131         assert p != NONEXISTENT_BUNDLE;
2132         // If the parent has expired, then this one must also expire. We
2133         // check only the immediate parent because the actual loading is
2134         // done from the root (base) to leaf (child) and the purpose of
2135         // checking is to propagate expiration towards the leaf. For
2136         // example, if the requested locale is ja_JP_JP and there are
2137         // bundles for all of the candidates in the cache, we have a list,
2138         //
2139         // base <- ja <- ja_JP <- ja_JP_JP
2140         //
2141         // If ja has expired, then it will reload ja and the list becomes a
2142         // tree.
2143         //
2144         // base <- ja (new)
2145         //  "   <- ja (expired) <- ja_JP <- ja_JP_JP
2146         //
2147         // When looking up ja_JP in the cache, it finds ja_JP in the cache
2148         // which references to the expired ja. Then, ja_JP is marked as
2149         // expired and removed from the cache. This will be propagated to
2150         // ja_JP_JP.
2151         //
2152         // Now, it's possible, for example, that while loading new ja_JP,
2153         // someone else has started loading the same bundle and finds the
2154         // base bundle has expired. Then, what we get from the first
2155         // getBundle call includes the expired base bundle. However, if
2156         // someone else didn't start its loading, we wouldn't know if the
2157         // base bundle has expired at the end of the loading process. The
2158         // expiration control doesn't guarantee that the returned bundle and
2159         // its parents haven't expired.
2160         //
2161         // We could check the entire parent chain to see if there's any in
2162         // the chain that has expired. But this process may never end. An
2163         // extreme case would be that getTimeToLive returns 0 and
2164         // needsReload always returns true.
2165         if (p != null && p.expired) {
2166             assert bundle != NONEXISTENT_BUNDLE;
2167             bundle.expired = true;
2168             bundle.cacheKey = null;
2169             cacheList.remove(cacheKey, bundleRef);
2170             bundle = null;
2171         } else {
2172             CacheKey key = bundleRef.getCacheKey();
2173             long expirationTime = key.expirationTime;
2174             if (!bundle.expired && expirationTime >= 0 &&
2175                 expirationTime <= System.currentTimeMillis()) {
2176                 // its TTL period has expired.
2177                 if (bundle != NONEXISTENT_BUNDLE) {
2178                     // Synchronize here to call needsReload to avoid
2179                     // redundant concurrent calls for the same bundle.
2180                     synchronized (bundle) {
2181                         expirationTime = key.expirationTime;
2182                         if (!bundle.expired && expirationTime >= 0 &&
2183                             expirationTime <= System.currentTimeMillis()) {
2184                             try {
2185                                 bundle.expired = control.needsReload(key.getName(),
2186                                                                      key.getLocale(),
2187                                                                      key.getFormat(),
2188                                                                      key.getLoader(),
2189                                                                      bundle,
2190                                                                      key.loadTime);
2191                             } catch (Exception e) {
2192                                 cacheKey.setCause(e);
2193                             }
2194                             if (bundle.expired) {
2195                                 // If the bundle needs to be reloaded, then
2196                                 // remove the bundle from the cache, but
2197                                 // return the bundle with the expired flag
2198                                 // on.
2199                                 bundle.cacheKey = null;
2200                                 cacheList.remove(cacheKey, bundleRef);
2201                             } else {
2202                                 // Update the expiration control info. and reuse
2203                                 // the same bundle instance
2204                                 setExpirationTime(key, control);
2205                             }
2206                         }
2207                     }
2208                 } else {
2209                     // We just remove NONEXISTENT_BUNDLE from the cache.
2210                     cacheList.remove(cacheKey, bundleRef);
2211                     bundle = null;
2212                 }
2213             }
2214         }
2215         return bundle;
2216     }
2217 
2218     /**
2219      * Put a new bundle in the cache.
2220      *
2221      * @param cacheKey the key for the resource bundle
2222      * @param bundle the resource bundle to be put in the cache
2223      * @return the ResourceBundle for the cacheKey; if someone has put
2224      * the bundle before this call, the one found in the cache is
2225      * returned.
2226      */
2227     private static ResourceBundle putBundleInCache(CacheKey cacheKey,
2228                                                    ResourceBundle bundle,
2229                                                    Control control) {
2230         setExpirationTime(cacheKey, control);
2231         if (cacheKey.expirationTime != Control.TTL_DONT_CACHE) {
2232             CacheKey key = (CacheKey) cacheKey.clone();
2233             BundleReference bundleRef = new BundleReference(bundle, referenceQueue, key);
2234             bundle.cacheKey = key;
2235 
2236             // Put the bundle in the cache if it's not been in the cache.
2237             BundleReference result = cacheList.putIfAbsent(key, bundleRef);
2238 
2239             // If someone else has put the same bundle in the cache before
2240             // us and it has not expired, we should use the one in the cache.
2241             if (result != null) {
2242                 ResourceBundle rb = result.get();
2243                 if (rb != null && !rb.expired) {
2244                     // Clear the back link to the cache key
2245                     bundle.cacheKey = null;
2246                     bundle = rb;
2247                     // Clear the reference in the BundleReference so that
2248                     // it won't be enqueued.
2249                     bundleRef.clear();
2250                 } else {
2251                     // Replace the invalid (garbage collected or expired)
2252                     // instance with the valid one.
2253                     cacheList.put(key, bundleRef);
2254                 }
2255             }
2256         }
2257         return bundle;
2258     }
2259 
2260     private static void setExpirationTime(CacheKey cacheKey, Control control) {
2261         long ttl = control.getTimeToLive(cacheKey.getName(),
2262                                          cacheKey.getLocale());
2263         if (ttl >= 0) {
2264             // If any expiration time is specified, set the time to be
2265             // expired in the cache.
2266             long now = System.currentTimeMillis();
2267             cacheKey.loadTime = now;
2268             cacheKey.expirationTime = now + ttl;
2269         } else if (ttl >= Control.TTL_NO_EXPIRATION_CONTROL) {
2270             cacheKey.expirationTime = ttl;
2271         } else {
2272             throw new IllegalArgumentException("Invalid Control: TTL=" + ttl);
2273         }
2274     }
2275 
2276     /**
2277      * Removes all resource bundles from the cache that have been loaded
2278      * by the caller's module using the caller's class loader.
2279      *
2280      * @since 1.6
2281      * @see ResourceBundle.Control#getTimeToLive(String,Locale)
2282      */
2283     @CallerSensitive
2284     public static final void clearCache() {
2285         Class<?> caller = Reflection.getCallerClass();
2286         clearCache(getLoader(caller), caller.getModule());
2287     }
2288 
2289     /**
2290      * Removes all resource bundles from the cache that have been loaded
2291      * by the caller's module using the given class loader.
2292      *
2293      * @param loader the class loader
2294      * @exception NullPointerException if <code>loader</code> is null
2295      * @since 1.6
2296      * @see ResourceBundle.Control#getTimeToLive(String,Locale)
2297      */
2298     @CallerSensitive
2299     public static final void clearCache(ClassLoader loader) {
2300         Objects.requireNonNull(loader);
2301         clearCache(loader, Reflection.getCallerClass().getModule());
2302     }
2303 
2304     /**
2305      * Removes all resource bundles from the cache that have been loaded by the
2306      * given {@code module}.
2307      *
2308      * @param module the module
2309      * @throws NullPointerException
2310      *         if {@code module} is {@code null}
2311      * @throws SecurityException
2312      *         if the caller doesn't have the permission to
2313      *         {@linkplain Module#getClassLoader() get the class loader}
2314      *         of the given {@code module}
2315      * @since 9
2316      * @see ResourceBundle.Control#getTimeToLive(String,Locale)
2317      */
2318     public static final void clearCache(Module module) {
2319         clearCache(module.getClassLoader(), module);
2320     }
2321 
2322     private static void clearCache(ClassLoader loader, Module module) {
2323         Set<CacheKey> set = cacheList.keySet();
2324         set.stream()
2325            .filter((key) -> (key.getLoader() == loader && key.getModule() == module))
2326            .forEach(set::remove);
2327     }
2328 
2329     /**
2330      * Gets an object for the given key from this resource bundle.
2331      * Returns null if this resource bundle does not contain an
2332      * object for the given key.
2333      *
2334      * @param key the key for the desired object
2335      * @exception NullPointerException if <code>key</code> is <code>null</code>
2336      * @return the object for the given key, or null
2337      */
2338     protected abstract Object handleGetObject(String key);
2339 
2340     /**
2341      * Returns an enumeration of the keys.
2342      *
2343      * @return an <code>Enumeration</code> of the keys contained in
2344      *         this <code>ResourceBundle</code> and its parent bundles.
2345      */
2346     public abstract Enumeration<String> getKeys();
2347 
2348     /**
2349      * Determines whether the given <code>key</code> is contained in
2350      * this <code>ResourceBundle</code> or its parent bundles.
2351      *
2352      * @param key
2353      *        the resource <code>key</code>
2354      * @return <code>true</code> if the given <code>key</code> is
2355      *        contained in this <code>ResourceBundle</code> or its
2356      *        parent bundles; <code>false</code> otherwise.
2357      * @exception NullPointerException
2358      *         if <code>key</code> is <code>null</code>
2359      * @since 1.6
2360      */
2361     public boolean containsKey(String key) {
2362         if (key == null) {
2363             throw new NullPointerException();
2364         }
2365         for (ResourceBundle rb = this; rb != null; rb = rb.parent) {
2366             if (rb.handleKeySet().contains(key)) {
2367                 return true;
2368             }
2369         }
2370         return false;
2371     }
2372 
2373     /**
2374      * Returns a <code>Set</code> of all keys contained in this
2375      * <code>ResourceBundle</code> and its parent bundles.
2376      *
2377      * @return a <code>Set</code> of all keys contained in this
2378      *         <code>ResourceBundle</code> and its parent bundles.
2379      * @since 1.6
2380      */
2381     public Set<String> keySet() {
2382         Set<String> keys = new HashSet<>();
2383         for (ResourceBundle rb = this; rb != null; rb = rb.parent) {
2384             keys.addAll(rb.handleKeySet());
2385         }
2386         return keys;
2387     }
2388 
2389     /**
2390      * Returns a <code>Set</code> of the keys contained <em>only</em>
2391      * in this <code>ResourceBundle</code>.
2392      *
2393      * <p>The default implementation returns a <code>Set</code> of the
2394      * keys returned by the {@link #getKeys() getKeys} method except
2395      * for the ones for which the {@link #handleGetObject(String)
2396      * handleGetObject} method returns <code>null</code>. Once the
2397      * <code>Set</code> has been created, the value is kept in this
2398      * <code>ResourceBundle</code> in order to avoid producing the
2399      * same <code>Set</code> in subsequent calls. Subclasses can
2400      * override this method for faster handling.
2401      *
2402      * @return a <code>Set</code> of the keys contained only in this
2403      *        <code>ResourceBundle</code>
2404      * @since 1.6
2405      */
2406     protected Set<String> handleKeySet() {
2407         if (keySet == null) {
2408             synchronized (this) {
2409                 if (keySet == null) {
2410                     Set<String> keys = new HashSet<>();
2411                     Enumeration<String> enumKeys = getKeys();
2412                     while (enumKeys.hasMoreElements()) {
2413                         String key = enumKeys.nextElement();
2414                         if (handleGetObject(key) != null) {
2415                             keys.add(key);
2416                         }
2417                     }
2418                     keySet = keys;
2419                 }
2420             }
2421         }
2422         return keySet;
2423     }
2424 
2425 
2426 
2427     /**
2428      * <code>ResourceBundle.Control</code> defines a set of callback methods
2429      * that are invoked by the {@link ResourceBundle#getBundle(String,
2430      * Locale, ClassLoader, Control) ResourceBundle.getBundle} factory
2431      * methods during the bundle loading process. In other words, a
2432      * <code>ResourceBundle.Control</code> collaborates with the factory
2433      * methods for loading resource bundles. The default implementation of
2434      * the callback methods provides the information necessary for the
2435      * factory methods to perform the <a
2436      * href="./ResourceBundle.html#default_behavior">default behavior</a>.
2437      * <a href="#note">Note that this class is not supported in named modules.</a>
2438      *
2439      * <p>In addition to the callback methods, the {@link
2440      * #toBundleName(String, Locale) toBundleName} and {@link
2441      * #toResourceName(String, String) toResourceName} methods are defined
2442      * primarily for convenience in implementing the callback
2443      * methods. However, the <code>toBundleName</code> method could be
2444      * overridden to provide different conventions in the organization and
2445      * packaging of localized resources.  The <code>toResourceName</code>
2446      * method is <code>final</code> to avoid use of wrong resource and class
2447      * name separators.
2448      *
2449      * <p>Two factory methods, {@link #getControl(List)} and {@link
2450      * #getNoFallbackControl(List)}, provide
2451      * <code>ResourceBundle.Control</code> instances that implement common
2452      * variations of the default bundle loading process.
2453      *
2454      * <p>The formats returned by the {@link Control#getFormats(String)
2455      * getFormats} method and candidate locales returned by the {@link
2456      * ResourceBundle.Control#getCandidateLocales(String, Locale)
2457      * getCandidateLocales} method must be consistent in all
2458      * <code>ResourceBundle.getBundle</code> invocations for the same base
2459      * bundle. Otherwise, the <code>ResourceBundle.getBundle</code> methods
2460      * may return unintended bundles. For example, if only
2461      * <code>"java.class"</code> is returned by the <code>getFormats</code>
2462      * method for the first call to <code>ResourceBundle.getBundle</code>
2463      * and only <code>"java.properties"</code> for the second call, then the
2464      * second call will return the class-based one that has been cached
2465      * during the first call.
2466      *
2467      * <p>A <code>ResourceBundle.Control</code> instance must be thread-safe
2468      * if it's simultaneously used by multiple threads.
2469      * <code>ResourceBundle.getBundle</code> does not synchronize to call
2470      * the <code>ResourceBundle.Control</code> methods. The default
2471      * implementations of the methods are thread-safe.
2472      *
2473      * <p>Applications can specify <code>ResourceBundle.Control</code>
2474      * instances returned by the <code>getControl</code> factory methods or
2475      * created from a subclass of <code>ResourceBundle.Control</code> to
2476      * customize the bundle loading process. The following are examples of
2477      * changing the default bundle loading process.
2478      *
2479      * <p><b>Example 1</b>
2480      *
2481      * <p>The following code lets <code>ResourceBundle.getBundle</code> look
2482      * up only properties-based resources.
2483      *
2484      * <pre>
2485      * import java.util.*;
2486      * import static java.util.ResourceBundle.Control.*;
2487      * ...
2488      * ResourceBundle bundle =
2489      *   ResourceBundle.getBundle("MyResources", new Locale("fr", "CH"),
2490      *                            ResourceBundle.Control.getControl(FORMAT_PROPERTIES));
2491      * </pre>
2492      *
2493      * Given the resource bundles in the <a
2494      * href="./ResourceBundle.html#default_behavior_example">example</a> in
2495      * the <code>ResourceBundle.getBundle</code> description, this
2496      * <code>ResourceBundle.getBundle</code> call loads
2497      * <code>MyResources_fr_CH.properties</code> whose parent is
2498      * <code>MyResources_fr.properties</code> whose parent is
2499      * <code>MyResources.properties</code>. (<code>MyResources_fr_CH.properties</code>
2500      * is not hidden, but <code>MyResources_fr_CH.class</code> is.)
2501      *
2502      * <p><b>Example 2</b>
2503      *
2504      * <p>The following is an example of loading XML-based bundles
2505      * using {@link Properties#loadFromXML(java.io.InputStream)
2506      * Properties.loadFromXML}.
2507      *
2508      * <pre>
2509      * ResourceBundle rb = ResourceBundle.getBundle("Messages",
2510      *     new ResourceBundle.Control() {
2511      *         public List&lt;String&gt; getFormats(String baseName) {
2512      *             if (baseName == null)
2513      *                 throw new NullPointerException();
2514      *             return Arrays.asList("xml");
2515      *         }
2516      *         public ResourceBundle newBundle(String baseName,
2517      *                                         Locale locale,
2518      *                                         String format,
2519      *                                         ClassLoader loader,
2520      *                                         boolean reload)
2521      *                          throws IllegalAccessException,
2522      *                                 InstantiationException,
2523      *                                 IOException {
2524      *             if (baseName == null || locale == null
2525      *                   || format == null || loader == null)
2526      *                 throw new NullPointerException();
2527      *             ResourceBundle bundle = null;
2528      *             if (format.equals("xml")) {
2529      *                 String bundleName = toBundleName(baseName, locale);
2530      *                 String resourceName = toResourceName(bundleName, format);
2531      *                 InputStream stream = null;
2532      *                 if (reload) {
2533      *                     URL url = loader.getResource(resourceName);
2534      *                     if (url != null) {
2535      *                         URLConnection connection = url.openConnection();
2536      *                         if (connection != null) {
2537      *                             // Disable caches to get fresh data for
2538      *                             // reloading.
2539      *                             connection.setUseCaches(false);
2540      *                             stream = connection.getInputStream();
2541      *                         }
2542      *                     }
2543      *                 } else {
2544      *                     stream = loader.getResourceAsStream(resourceName);
2545      *                 }
2546      *                 if (stream != null) {
2547      *                     BufferedInputStream bis = new BufferedInputStream(stream);
2548      *                     bundle = new XMLResourceBundle(bis);
2549      *                     bis.close();
2550      *                 }
2551      *             }
2552      *             return bundle;
2553      *         }
2554      *     });
2555      *
2556      * ...
2557      *
2558      * private static class XMLResourceBundle extends ResourceBundle {
2559      *     private Properties props;
2560      *     XMLResourceBundle(InputStream stream) throws IOException {
2561      *         props = new Properties();
2562      *         props.loadFromXML(stream);
2563      *     }
2564      *     protected Object handleGetObject(String key) {
2565      *         return props.getProperty(key);
2566      *     }
2567      *     public Enumeration&lt;String&gt; getKeys() {
2568      *         ...
2569      *     }
2570      * }
2571      * </pre>
2572      *
2573      * @apiNote <a name="note">{@code ResourceBundle.Control} is not supported
2574      * in named modules.</a> If the {@code ResourceBundle.getBundle} method with
2575      * a {@code ResourceBundle.Control} is called in a named module, the method
2576      * will throw an {@link UnsupportedOperationException}. Any service providers
2577      * of {@link ResourceBundleControlProvider} are ignored in named modules.
2578      *
2579      * @since 1.6
2580      * @see java.util.spi.ResourceBundleProvider
2581      */
2582     public static class Control {
2583         /**
2584          * The default format <code>List</code>, which contains the strings
2585          * <code>"java.class"</code> and <code>"java.properties"</code>, in
2586          * this order. This <code>List</code> is unmodifiable.
2587          *
2588          * @see #getFormats(String)
2589          */
2590         public static final List<String> FORMAT_DEFAULT
2591             = List.of("java.class", "java.properties");
2592 
2593         /**
2594          * The class-only format <code>List</code> containing
2595          * <code>"java.class"</code>. This <code>List</code> is unmodifiable.
2596          *
2597          * @see #getFormats(String)
2598          */
2599         public static final List<String> FORMAT_CLASS = List.of("java.class");
2600 
2601         /**
2602          * The properties-only format <code>List</code> containing
2603          * <code>"java.properties"</code>. This <code>List</code> is unmodifiable.
2604          *
2605          * @see #getFormats(String)
2606          */
2607         public static final List<String> FORMAT_PROPERTIES
2608             = List.of("java.properties");
2609 
2610         /**
2611          * The time-to-live constant for not caching loaded resource bundle
2612          * instances.
2613          *
2614          * @see #getTimeToLive(String, Locale)
2615          */
2616         public static final long TTL_DONT_CACHE = -1;
2617 
2618         /**
2619          * The time-to-live constant for disabling the expiration control
2620          * for loaded resource bundle instances in the cache.
2621          *
2622          * @see #getTimeToLive(String, Locale)
2623          */
2624         public static final long TTL_NO_EXPIRATION_CONTROL = -2;
2625 
2626         private static final Control INSTANCE = new Control();
2627 
2628         /**
2629          * Sole constructor. (For invocation by subclass constructors,
2630          * typically implicit.)
2631          */
2632         protected Control() {
2633         }
2634 
2635         /**
2636          * Returns a <code>ResourceBundle.Control</code> in which the {@link
2637          * #getFormats(String) getFormats} method returns the specified
2638          * <code>formats</code>. The <code>formats</code> must be equal to
2639          * one of {@link Control#FORMAT_PROPERTIES}, {@link
2640          * Control#FORMAT_CLASS} or {@link
2641          * Control#FORMAT_DEFAULT}. <code>ResourceBundle.Control</code>
2642          * instances returned by this method are singletons and thread-safe.
2643          *
2644          * <p>Specifying {@link Control#FORMAT_DEFAULT} is equivalent to
2645          * instantiating the <code>ResourceBundle.Control</code> class,
2646          * except that this method returns a singleton.
2647          *
2648          * @param formats
2649          *        the formats to be returned by the
2650          *        <code>ResourceBundle.Control.getFormats</code> method
2651          * @return a <code>ResourceBundle.Control</code> supporting the
2652          *        specified <code>formats</code>
2653          * @exception NullPointerException
2654          *        if <code>formats</code> is <code>null</code>
2655          * @exception IllegalArgumentException
2656          *        if <code>formats</code> is unknown
2657          */
2658         public static final Control getControl(List<String> formats) {
2659             if (formats.equals(Control.FORMAT_PROPERTIES)) {
2660                 return SingleFormatControl.PROPERTIES_ONLY;
2661             }
2662             if (formats.equals(Control.FORMAT_CLASS)) {
2663                 return SingleFormatControl.CLASS_ONLY;
2664             }
2665             if (formats.equals(Control.FORMAT_DEFAULT)) {
2666                 return Control.INSTANCE;
2667             }
2668             throw new IllegalArgumentException();
2669         }
2670 
2671         /**
2672          * Returns a <code>ResourceBundle.Control</code> in which the {@link
2673          * #getFormats(String) getFormats} method returns the specified
2674          * <code>formats</code> and the {@link
2675          * Control#getFallbackLocale(String, Locale) getFallbackLocale}
2676          * method returns <code>null</code>. The <code>formats</code> must
2677          * be equal to one of {@link Control#FORMAT_PROPERTIES}, {@link
2678          * Control#FORMAT_CLASS} or {@link Control#FORMAT_DEFAULT}.
2679          * <code>ResourceBundle.Control</code> instances returned by this
2680          * method are singletons and thread-safe.
2681          *
2682          * @param formats
2683          *        the formats to be returned by the
2684          *        <code>ResourceBundle.Control.getFormats</code> method
2685          * @return a <code>ResourceBundle.Control</code> supporting the
2686          *        specified <code>formats</code> with no fallback
2687          *        <code>Locale</code> support
2688          * @exception NullPointerException
2689          *        if <code>formats</code> is <code>null</code>
2690          * @exception IllegalArgumentException
2691          *        if <code>formats</code> is unknown
2692          */
2693         public static final Control getNoFallbackControl(List<String> formats) {
2694             if (formats.equals(Control.FORMAT_DEFAULT)) {
2695                 return NoFallbackControl.NO_FALLBACK;
2696             }
2697             if (formats.equals(Control.FORMAT_PROPERTIES)) {
2698                 return NoFallbackControl.PROPERTIES_ONLY_NO_FALLBACK;
2699             }
2700             if (formats.equals(Control.FORMAT_CLASS)) {
2701                 return NoFallbackControl.CLASS_ONLY_NO_FALLBACK;
2702             }
2703             throw new IllegalArgumentException();
2704         }
2705 
2706         /**
2707          * Returns a <code>List</code> of <code>String</code>s containing
2708          * formats to be used to load resource bundles for the given
2709          * <code>baseName</code>. The <code>ResourceBundle.getBundle</code>
2710          * factory method tries to load resource bundles with formats in the
2711          * order specified by the list. The list returned by this method
2712          * must have at least one <code>String</code>. The predefined
2713          * formats are <code>"java.class"</code> for class-based resource
2714          * bundles and <code>"java.properties"</code> for {@linkplain
2715          * PropertyResourceBundle properties-based} ones. Strings starting
2716          * with <code>"java."</code> are reserved for future extensions and
2717          * must not be used by application-defined formats.
2718          *
2719          * <p>It is not a requirement to return an immutable (unmodifiable)
2720          * <code>List</code>.  However, the returned <code>List</code> must
2721          * not be mutated after it has been returned by
2722          * <code>getFormats</code>.
2723          *
2724          * <p>The default implementation returns {@link #FORMAT_DEFAULT} so
2725          * that the <code>ResourceBundle.getBundle</code> factory method
2726          * looks up first class-based resource bundles, then
2727          * properties-based ones.
2728          *
2729          * @param baseName
2730          *        the base name of the resource bundle, a fully qualified class
2731          *        name
2732          * @return a <code>List</code> of <code>String</code>s containing
2733          *        formats for loading resource bundles.
2734          * @exception NullPointerException
2735          *        if <code>baseName</code> is null
2736          * @see #FORMAT_DEFAULT
2737          * @see #FORMAT_CLASS
2738          * @see #FORMAT_PROPERTIES
2739          */
2740         public List<String> getFormats(String baseName) {
2741             if (baseName == null) {
2742                 throw new NullPointerException();
2743             }
2744             return FORMAT_DEFAULT;
2745         }
2746 
2747         /**
2748          * Returns a <code>List</code> of <code>Locale</code>s as candidate
2749          * locales for <code>baseName</code> and <code>locale</code>. This
2750          * method is called by the <code>ResourceBundle.getBundle</code>
2751          * factory method each time the factory method tries finding a
2752          * resource bundle for a target <code>Locale</code>.
2753          *
2754          * <p>The sequence of the candidate locales also corresponds to the
2755          * runtime resource lookup path (also known as the <I>parent
2756          * chain</I>), if the corresponding resource bundles for the
2757          * candidate locales exist and their parents are not defined by
2758          * loaded resource bundles themselves.  The last element of the list
2759          * must be a {@linkplain Locale#ROOT root locale} if it is desired to
2760          * have the base bundle as the terminal of the parent chain.
2761          *
2762          * <p>If the given locale is equal to <code>Locale.ROOT</code> (the
2763          * root locale), a <code>List</code> containing only the root
2764          * <code>Locale</code> must be returned. In this case, the
2765          * <code>ResourceBundle.getBundle</code> factory method loads only
2766          * the base bundle as the resulting resource bundle.
2767          *
2768          * <p>It is not a requirement to return an immutable (unmodifiable)
2769          * <code>List</code>. However, the returned <code>List</code> must not
2770          * be mutated after it has been returned by
2771          * <code>getCandidateLocales</code>.
2772          *
2773          * <p>The default implementation returns a <code>List</code> containing
2774          * <code>Locale</code>s using the rules described below.  In the
2775          * description below, <em>L</em>, <em>S</em>, <em>C</em> and <em>V</em>
2776          * respectively represent non-empty language, script, country, and
2777          * variant.  For example, [<em>L</em>, <em>C</em>] represents a
2778          * <code>Locale</code> that has non-empty values only for language and
2779          * country.  The form <em>L</em>("xx") represents the (non-empty)
2780          * language value is "xx".  For all cases, <code>Locale</code>s whose
2781          * final component values are empty strings are omitted.
2782          *
2783          * <ol><li>For an input <code>Locale</code> with an empty script value,
2784          * append candidate <code>Locale</code>s by omitting the final component
2785          * one by one as below:
2786          *
2787          * <ul>
2788          * <li> [<em>L</em>, <em>C</em>, <em>V</em>] </li>
2789          * <li> [<em>L</em>, <em>C</em>] </li>
2790          * <li> [<em>L</em>] </li>
2791          * <li> <code>Locale.ROOT</code> </li>
2792          * </ul></li>
2793          *
2794          * <li>For an input <code>Locale</code> with a non-empty script value,
2795          * append candidate <code>Locale</code>s by omitting the final component
2796          * up to language, then append candidates generated from the
2797          * <code>Locale</code> with country and variant restored:
2798          *
2799          * <ul>
2800          * <li> [<em>L</em>, <em>S</em>, <em>C</em>, <em>V</em>]</li>
2801          * <li> [<em>L</em>, <em>S</em>, <em>C</em>]</li>
2802          * <li> [<em>L</em>, <em>S</em>]</li>
2803          * <li> [<em>L</em>, <em>C</em>, <em>V</em>]</li>
2804          * <li> [<em>L</em>, <em>C</em>]</li>
2805          * <li> [<em>L</em>]</li>
2806          * <li> <code>Locale.ROOT</code></li>
2807          * </ul></li>
2808          *
2809          * <li>For an input <code>Locale</code> with a variant value consisting
2810          * of multiple subtags separated by underscore, generate candidate
2811          * <code>Locale</code>s by omitting the variant subtags one by one, then
2812          * insert them after every occurrence of <code> Locale</code>s with the
2813          * full variant value in the original list.  For example, if the
2814          * the variant consists of two subtags <em>V1</em> and <em>V2</em>:
2815          *
2816          * <ul>
2817          * <li> [<em>L</em>, <em>S</em>, <em>C</em>, <em>V1</em>, <em>V2</em>]</li>
2818          * <li> [<em>L</em>, <em>S</em>, <em>C</em>, <em>V1</em>]</li>
2819          * <li> [<em>L</em>, <em>S</em>, <em>C</em>]</li>
2820          * <li> [<em>L</em>, <em>S</em>]</li>
2821          * <li> [<em>L</em>, <em>C</em>, <em>V1</em>, <em>V2</em>]</li>
2822          * <li> [<em>L</em>, <em>C</em>, <em>V1</em>]</li>
2823          * <li> [<em>L</em>, <em>C</em>]</li>
2824          * <li> [<em>L</em>]</li>
2825          * <li> <code>Locale.ROOT</code></li>
2826          * </ul></li>
2827          *
2828          * <li>Special cases for Chinese.  When an input <code>Locale</code> has the
2829          * language "zh" (Chinese) and an empty script value, either "Hans" (Simplified) or
2830          * "Hant" (Traditional) might be supplied, depending on the country.
2831          * When the country is "CN" (China) or "SG" (Singapore), "Hans" is supplied.
2832          * When the country is "HK" (Hong Kong SAR China), "MO" (Macau SAR China),
2833          * or "TW" (Taiwan), "Hant" is supplied.  For all other countries or when the country
2834          * is empty, no script is supplied.  For example, for <code>Locale("zh", "CN")
2835          * </code>, the candidate list will be:
2836          * <ul>
2837          * <li> [<em>L</em>("zh"), <em>S</em>("Hans"), <em>C</em>("CN")]</li>
2838          * <li> [<em>L</em>("zh"), <em>S</em>("Hans")]</li>
2839          * <li> [<em>L</em>("zh"), <em>C</em>("CN")]</li>
2840          * <li> [<em>L</em>("zh")]</li>
2841          * <li> <code>Locale.ROOT</code></li>
2842          * </ul>
2843          *
2844          * For <code>Locale("zh", "TW")</code>, the candidate list will be:
2845          * <ul>
2846          * <li> [<em>L</em>("zh"), <em>S</em>("Hant"), <em>C</em>("TW")]</li>
2847          * <li> [<em>L</em>("zh"), <em>S</em>("Hant")]</li>
2848          * <li> [<em>L</em>("zh"), <em>C</em>("TW")]</li>
2849          * <li> [<em>L</em>("zh")]</li>
2850          * <li> <code>Locale.ROOT</code></li>
2851          * </ul></li>
2852          *
2853          * <li>Special cases for Norwegian.  Both <code>Locale("no", "NO",
2854          * "NY")</code> and <code>Locale("nn", "NO")</code> represent Norwegian
2855          * Nynorsk.  When a locale's language is "nn", the standard candidate
2856          * list is generated up to [<em>L</em>("nn")], and then the following
2857          * candidates are added:
2858          *
2859          * <ul><li> [<em>L</em>("no"), <em>C</em>("NO"), <em>V</em>("NY")]</li>
2860          * <li> [<em>L</em>("no"), <em>C</em>("NO")]</li>
2861          * <li> [<em>L</em>("no")]</li>
2862          * <li> <code>Locale.ROOT</code></li>
2863          * </ul>
2864          *
2865          * If the locale is exactly <code>Locale("no", "NO", "NY")</code>, it is first
2866          * converted to <code>Locale("nn", "NO")</code> and then the above procedure is
2867          * followed.
2868          *
2869          * <p>Also, Java treats the language "no" as a synonym of Norwegian
2870          * Bokmål "nb".  Except for the single case <code>Locale("no",
2871          * "NO", "NY")</code> (handled above), when an input <code>Locale</code>
2872          * has language "no" or "nb", candidate <code>Locale</code>s with
2873          * language code "no" and "nb" are interleaved, first using the
2874          * requested language, then using its synonym. For example,
2875          * <code>Locale("nb", "NO", "POSIX")</code> generates the following
2876          * candidate list:
2877          *
2878          * <ul>
2879          * <li> [<em>L</em>("nb"), <em>C</em>("NO"), <em>V</em>("POSIX")]</li>
2880          * <li> [<em>L</em>("no"), <em>C</em>("NO"), <em>V</em>("POSIX")]</li>
2881          * <li> [<em>L</em>("nb"), <em>C</em>("NO")]</li>
2882          * <li> [<em>L</em>("no"), <em>C</em>("NO")]</li>
2883          * <li> [<em>L</em>("nb")]</li>
2884          * <li> [<em>L</em>("no")]</li>
2885          * <li> <code>Locale.ROOT</code></li>
2886          * </ul>
2887          *
2888          * <code>Locale("no", "NO", "POSIX")</code> would generate the same list
2889          * except that locales with "no" would appear before the corresponding
2890          * locales with "nb".</li>
2891          * </ol>
2892          *
2893          * <p>The default implementation uses an {@link ArrayList} that
2894          * overriding implementations may modify before returning it to the
2895          * caller. However, a subclass must not modify it after it has
2896          * been returned by <code>getCandidateLocales</code>.
2897          *
2898          * <p>For example, if the given <code>baseName</code> is "Messages"
2899          * and the given <code>locale</code> is
2900          * <code>Locale("ja",&nbsp;"",&nbsp;"XX")</code>, then a
2901          * <code>List</code> of <code>Locale</code>s:
2902          * <pre>
2903          *     Locale("ja", "", "XX")
2904          *     Locale("ja")
2905          *     Locale.ROOT
2906          * </pre>
2907          * is returned. And if the resource bundles for the "ja" and
2908          * "" <code>Locale</code>s are found, then the runtime resource
2909          * lookup path (parent chain) is:
2910          * <pre>{@code
2911          *     Messages_ja -> Messages
2912          * }</pre>
2913          *
2914          * @param baseName
2915          *        the base name of the resource bundle, a fully
2916          *        qualified class name
2917          * @param locale
2918          *        the locale for which a resource bundle is desired
2919          * @return a <code>List</code> of candidate
2920          *        <code>Locale</code>s for the given <code>locale</code>
2921          * @exception NullPointerException
2922          *        if <code>baseName</code> or <code>locale</code> is
2923          *        <code>null</code>
2924          */
2925         public List<Locale> getCandidateLocales(String baseName, Locale locale) {
2926             if (baseName == null) {
2927                 throw new NullPointerException();
2928             }
2929             return new ArrayList<>(CANDIDATES_CACHE.get(locale.getBaseLocale()));
2930         }
2931 
2932         private static final CandidateListCache CANDIDATES_CACHE = new CandidateListCache();
2933 
2934         private static class CandidateListCache extends LocaleObjectCache<BaseLocale, List<Locale>> {
2935             protected List<Locale> createObject(BaseLocale base) {
2936                 String language = base.getLanguage();
2937                 String script = base.getScript();
2938                 String region = base.getRegion();
2939                 String variant = base.getVariant();
2940 
2941                 // Special handling for Norwegian
2942                 boolean isNorwegianBokmal = false;
2943                 boolean isNorwegianNynorsk = false;
2944                 if (language.equals("no")) {
2945                     if (region.equals("NO") && variant.equals("NY")) {
2946                         variant = "";
2947                         isNorwegianNynorsk = true;
2948                     } else {
2949                         isNorwegianBokmal = true;
2950                     }
2951                 }
2952                 if (language.equals("nb") || isNorwegianBokmal) {
2953                     List<Locale> tmpList = getDefaultList("nb", script, region, variant);
2954                     // Insert a locale replacing "nb" with "no" for every list entry
2955                     List<Locale> bokmalList = new LinkedList<>();
2956                     for (Locale l : tmpList) {
2957                         bokmalList.add(l);
2958                         if (l.getLanguage().length() == 0) {
2959                             break;
2960                         }
2961                         bokmalList.add(Locale.getInstance("no", l.getScript(), l.getCountry(),
2962                                 l.getVariant(), null));
2963                     }
2964                     return bokmalList;
2965                 } else if (language.equals("nn") || isNorwegianNynorsk) {
2966                     // Insert no_NO_NY, no_NO, no after nn
2967                     List<Locale> nynorskList = getDefaultList("nn", script, region, variant);
2968                     int idx = nynorskList.size() - 1;
2969                     nynorskList.add(idx++, Locale.getInstance("no", "NO", "NY"));
2970                     nynorskList.add(idx++, Locale.getInstance("no", "NO", ""));
2971                     nynorskList.add(idx++, Locale.getInstance("no", "", ""));
2972                     return nynorskList;
2973                 }
2974                 // Special handling for Chinese
2975                 else if (language.equals("zh")) {
2976                     if (script.length() == 0 && region.length() > 0) {
2977                         // Supply script for users who want to use zh_Hans/zh_Hant
2978                         // as bundle names (recommended for Java7+)
2979                         switch (region) {
2980                         case "TW":
2981                         case "HK":
2982                         case "MO":
2983                             script = "Hant";
2984                             break;
2985                         case "CN":
2986                         case "SG":
2987                             script = "Hans";
2988                             break;
2989                         }
2990                     } else if (script.length() > 0 && region.length() == 0) {
2991                         // Supply region(country) for users who still package Chinese
2992                         // bundles using old convension.
2993                         switch (script) {
2994                         case "Hans":
2995                             region = "CN";
2996                             break;
2997                         case "Hant":
2998                             region = "TW";
2999                             break;
3000                         }
3001                     }
3002                 }
3003 
3004                 return getDefaultList(language, script, region, variant);
3005             }
3006 
3007             private static List<Locale> getDefaultList(String language, String script, String region, String variant) {
3008                 List<String> variants = null;
3009 
3010                 if (variant.length() > 0) {
3011                     variants = new LinkedList<>();
3012                     int idx = variant.length();
3013                     while (idx != -1) {
3014                         variants.add(variant.substring(0, idx));
3015                         idx = variant.lastIndexOf('_', --idx);
3016                     }
3017                 }
3018 
3019                 List<Locale> list = new LinkedList<>();
3020 
3021                 if (variants != null) {
3022                     for (String v : variants) {
3023                         list.add(Locale.getInstance(language, script, region, v, null));
3024                     }
3025                 }
3026                 if (region.length() > 0) {
3027                     list.add(Locale.getInstance(language, script, region, "", null));
3028                 }
3029                 if (script.length() > 0) {
3030                     list.add(Locale.getInstance(language, script, "", "", null));
3031 
3032                     // With script, after truncating variant, region and script,
3033                     // start over without script.
3034                     if (variants != null) {
3035                         for (String v : variants) {
3036                             list.add(Locale.getInstance(language, "", region, v, null));
3037                         }
3038                     }
3039                     if (region.length() > 0) {
3040                         list.add(Locale.getInstance(language, "", region, "", null));
3041                     }
3042                 }
3043                 if (language.length() > 0) {
3044                     list.add(Locale.getInstance(language, "", "", "", null));
3045                 }
3046                 // Add root locale at the end
3047                 list.add(Locale.ROOT);
3048 
3049                 return list;
3050             }
3051         }
3052 
3053         /**
3054          * Returns a <code>Locale</code> to be used as a fallback locale for
3055          * further resource bundle searches by the
3056          * <code>ResourceBundle.getBundle</code> factory method. This method
3057          * is called from the factory method every time when no resulting
3058          * resource bundle has been found for <code>baseName</code> and
3059          * <code>locale</code>, where locale is either the parameter for
3060          * <code>ResourceBundle.getBundle</code> or the previous fallback
3061          * locale returned by this method.
3062          *
3063          * <p>The method returns <code>null</code> if no further fallback
3064          * search is desired.
3065          *
3066          * <p>The default implementation returns the {@linkplain
3067          * Locale#getDefault() default <code>Locale</code>} if the given
3068          * <code>locale</code> isn't the default one.  Otherwise,
3069          * <code>null</code> is returned.
3070          *
3071          * @param baseName
3072          *        the base name of the resource bundle, a fully
3073          *        qualified class name for which
3074          *        <code>ResourceBundle.getBundle</code> has been
3075          *        unable to find any resource bundles (except for the
3076          *        base bundle)
3077          * @param locale
3078          *        the <code>Locale</code> for which
3079          *        <code>ResourceBundle.getBundle</code> has been
3080          *        unable to find any resource bundles (except for the
3081          *        base bundle)
3082          * @return a <code>Locale</code> for the fallback search,
3083          *        or <code>null</code> if no further fallback search
3084          *        is desired.
3085          * @exception NullPointerException
3086          *        if <code>baseName</code> or <code>locale</code>
3087          *        is <code>null</code>
3088          */
3089         public Locale getFallbackLocale(String baseName, Locale locale) {
3090             if (baseName == null) {
3091                 throw new NullPointerException();
3092             }
3093             Locale defaultLocale = Locale.getDefault();
3094             return locale.equals(defaultLocale) ? null : defaultLocale;
3095         }
3096 
3097         /**
3098          * Instantiates a resource bundle for the given bundle name of the
3099          * given format and locale, using the given class loader if
3100          * necessary. This method returns <code>null</code> if there is no
3101          * resource bundle available for the given parameters. If a resource
3102          * bundle can't be instantiated due to an unexpected error, the
3103          * error must be reported by throwing an <code>Error</code> or
3104          * <code>Exception</code> rather than simply returning
3105          * <code>null</code>.
3106          *
3107          * <p>If the <code>reload</code> flag is <code>true</code>, it
3108          * indicates that this method is being called because the previously
3109          * loaded resource bundle has expired.
3110          *
3111          * @implSpec
3112          *
3113          * Resource bundles in named modules are subject to the encapsulation
3114          * rules specified by {@link Module#getResourceAsStream Module.getResourceAsStream}.
3115          * A resource bundle in a named module visible to the given class loader
3116          * is accessible when the package of the resource file corresponding
3117          * to the resource bundle is open unconditionally.
3118          *
3119          * <p>The default implementation instantiates a
3120          * <code>ResourceBundle</code> as follows.
3121          *
3122          * <ul>
3123          *
3124          * <li>The bundle name is obtained by calling {@link
3125          * #toBundleName(String, Locale) toBundleName(baseName,
3126          * locale)}.</li>
3127          *
3128          * <li>If <code>format</code> is <code>"java.class"</code>, the
3129          * {@link Class} specified by the bundle name is loaded with the
3130          * given class loader. If the {@code Class} is found and accessible
3131          * then the <code>ResourceBundle</code> is instantiated.  The
3132          * resource bundle is accessible if the package of the bundle class file
3133          * is open unconditionally; otherwise, {@code IllegalAccessException}
3134          * will be thrown.
3135          * Note that the <code>reload</code> flag is ignored for loading
3136          * class-based resource bundles in this default implementation.
3137          * </li>
3138          *
3139          * <li>If <code>format</code> is <code>"java.properties"</code>,
3140          * {@link #toResourceName(String, String) toResourceName(bundlename,
3141          * "properties")} is called to get the resource name.
3142          * If <code>reload</code> is <code>true</code>, {@link
3143          * ClassLoader#getResource(String) load.getResource} is called
3144          * to get a {@link URL} for creating a {@link
3145          * URLConnection}. This <code>URLConnection</code> is used to
3146          * {@linkplain URLConnection#setUseCaches(boolean) disable the
3147          * caches} of the underlying resource loading layers,
3148          * and to {@linkplain URLConnection#getInputStream() get an
3149          * <code>InputStream</code>}.
3150          * Otherwise, {@link ClassLoader#getResourceAsStream(String)
3151          * loader.getResourceAsStream} is called to get an {@link
3152          * InputStream}. Then, a {@link
3153          * PropertyResourceBundle} is constructed with the
3154          * <code>InputStream</code>.</li>
3155          *
3156          * <li>If <code>format</code> is neither <code>"java.class"</code>
3157          * nor <code>"java.properties"</code>, an
3158          * <code>IllegalArgumentException</code> is thrown.</li>
3159          *
3160          * </ul>
3161          *
3162          * @param baseName
3163          *        the base bundle name of the resource bundle, a fully
3164          *        qualified class name
3165          * @param locale
3166          *        the locale for which the resource bundle should be
3167          *        instantiated
3168          * @param format
3169          *        the resource bundle format to be loaded
3170          * @param loader
3171          *        the <code>ClassLoader</code> to use to load the bundle
3172          * @param reload
3173          *        the flag to indicate bundle reloading; <code>true</code>
3174          *        if reloading an expired resource bundle,
3175          *        <code>false</code> otherwise
3176          * @return the resource bundle instance,
3177          *        or <code>null</code> if none could be found.
3178          * @exception NullPointerException
3179          *        if <code>bundleName</code>, <code>locale</code>,
3180          *        <code>format</code>, or <code>loader</code> is
3181          *        <code>null</code>, or if <code>null</code> is returned by
3182          *        {@link #toBundleName(String, Locale) toBundleName}
3183          * @exception IllegalArgumentException
3184          *        if <code>format</code> is unknown, or if the resource
3185          *        found for the given parameters contains malformed data.
3186          * @exception ClassCastException
3187          *        if the loaded class cannot be cast to <code>ResourceBundle</code>
3188          * @exception IllegalAccessException
3189          *        if the class or its nullary constructor is not
3190          *        accessible.
3191          * @exception InstantiationException
3192          *        if the instantiation of a class fails for some other
3193          *        reason.
3194          * @exception ExceptionInInitializerError
3195          *        if the initialization provoked by this method fails.
3196          * @exception SecurityException
3197          *        If a security manager is present and creation of new
3198          *        instances is denied. See {@link Class#newInstance()}
3199          *        for details.
3200          * @exception IOException
3201          *        if an error occurred when reading resources using
3202          *        any I/O operations
3203          * @see java.util.spi.ResourceBundleProvider#getBundle(String, Locale)
3204          */
3205         public ResourceBundle newBundle(String baseName, Locale locale, String format,
3206                                         ClassLoader loader, boolean reload)
3207                     throws IllegalAccessException, InstantiationException, IOException {
3208             /*
3209              * Legacy mechanism to locate resource bundle in unnamed module only
3210              * that is visible to the given loader and accessible to the given caller.
3211              */
3212             String bundleName = toBundleName(baseName, locale);
3213             ResourceBundle bundle = null;
3214             if (format.equals("java.class")) {
3215                 try {
3216                     Class<?> c = loader.loadClass(bundleName);
3217                     // If the class isn't a ResourceBundle subclass, throw a
3218                     // ClassCastException.
3219                     if (ResourceBundle.class.isAssignableFrom(c)) {
3220                         @SuppressWarnings("unchecked")
3221                         Class<ResourceBundle> bundleClass = (Class<ResourceBundle>)c;
3222                         Module m = bundleClass.getModule();
3223 
3224                         // To access a resource bundle in a named module,
3225                         // either class-based or properties-based, the resource
3226                         // bundle must be opened unconditionally,
3227                         // same rule as accessing a resource file.
3228                         if (m.isNamed() && !m.isOpen(bundleClass.getPackageName())) {
3229                             throw new IllegalAccessException("unnamed module can't load " +
3230                                 bundleClass.getName() + " in " + m.toString());
3231                         }
3232                         try {
3233                             // bundle in a unnamed module
3234                             Constructor<ResourceBundle> ctor = bundleClass.getConstructor();
3235                             if (!Modifier.isPublic(ctor.getModifiers())) {
3236                                 return null;
3237                             }
3238 
3239                             // java.base may not be able to read the bundleClass's module.
3240                             PrivilegedAction<Void> pa1 = () -> { ctor.setAccessible(true); return null; };
3241                             AccessController.doPrivileged(pa1);
3242                             bundle = ctor.newInstance((Object[]) null);
3243                         } catch (InvocationTargetException e) {
3244                             uncheckedThrow(e);
3245                         }
3246                     } else {
3247                         throw new ClassCastException(c.getName()
3248                                 + " cannot be cast to ResourceBundle");
3249                     }
3250                 } catch (ClassNotFoundException|NoSuchMethodException e) {
3251                 }
3252             } else if (format.equals("java.properties")) {
3253                 final String resourceName = toResourceName0(bundleName, "properties");
3254                 if (resourceName == null) {
3255                     return bundle;
3256                 }
3257 
3258                 final boolean reloadFlag = reload;
3259                 InputStream stream = null;
3260                 try {
3261                     stream = AccessController.doPrivileged(
3262                         new PrivilegedExceptionAction<>() {
3263                             public InputStream run() throws IOException {
3264                                 URL url = loader.getResource(resourceName);
3265                                 if (url == null) return null;
3266 
3267                                 URLConnection connection = url.openConnection();
3268                                 if (reloadFlag) {
3269                                     // Disable caches to get fresh data for
3270                                     // reloading.
3271                                     connection.setUseCaches(false);
3272                                 }
3273                                 return connection.getInputStream();
3274                             }
3275                         });
3276                 } catch (PrivilegedActionException e) {
3277                     throw (IOException) e.getException();
3278                 }
3279                 if (stream != null) {
3280                     try {
3281                         bundle = new PropertyResourceBundle(stream);
3282                     } finally {
3283                         stream.close();
3284                     }
3285                 }
3286             } else {
3287                 throw new IllegalArgumentException("unknown format: " + format);
3288             }
3289             return bundle;
3290         }
3291 
3292         /**
3293          * Returns the time-to-live (TTL) value for resource bundles that
3294          * are loaded under this
3295          * <code>ResourceBundle.Control</code>. Positive time-to-live values
3296          * specify the number of milliseconds a bundle can remain in the
3297          * cache without being validated against the source data from which
3298          * it was constructed. The value 0 indicates that a bundle must be
3299          * validated each time it is retrieved from the cache. {@link
3300          * #TTL_DONT_CACHE} specifies that loaded resource bundles are not
3301          * put in the cache. {@link #TTL_NO_EXPIRATION_CONTROL} specifies
3302          * that loaded resource bundles are put in the cache with no
3303          * expiration control.
3304          *
3305          * <p>The expiration affects only the bundle loading process by the
3306          * <code>ResourceBundle.getBundle</code> factory method.  That is,
3307          * if the factory method finds a resource bundle in the cache that
3308          * has expired, the factory method calls the {@link
3309          * #needsReload(String, Locale, String, ClassLoader, ResourceBundle,
3310          * long) needsReload} method to determine whether the resource
3311          * bundle needs to be reloaded. If <code>needsReload</code> returns
3312          * <code>true</code>, the cached resource bundle instance is removed
3313          * from the cache. Otherwise, the instance stays in the cache,
3314          * updated with the new TTL value returned by this method.
3315          *
3316          * <p>All cached resource bundles are subject to removal from the
3317          * cache due to memory constraints of the runtime environment.
3318          * Returning a large positive value doesn't mean to lock loaded
3319          * resource bundles in the cache.
3320          *
3321          * <p>The default implementation returns {@link #TTL_NO_EXPIRATION_CONTROL}.
3322          *
3323          * @param baseName
3324          *        the base name of the resource bundle for which the
3325          *        expiration value is specified.
3326          * @param locale
3327          *        the locale of the resource bundle for which the
3328          *        expiration value is specified.
3329          * @return the time (0 or a positive millisecond offset from the
3330          *        cached time) to get loaded bundles expired in the cache,
3331          *        {@link #TTL_NO_EXPIRATION_CONTROL} to disable the
3332          *        expiration control, or {@link #TTL_DONT_CACHE} to disable
3333          *        caching.
3334          * @exception NullPointerException
3335          *        if <code>baseName</code> or <code>locale</code> is
3336          *        <code>null</code>
3337          */
3338         public long getTimeToLive(String baseName, Locale locale) {
3339             if (baseName == null || locale == null) {
3340                 throw new NullPointerException();
3341             }
3342             return TTL_NO_EXPIRATION_CONTROL;
3343         }
3344 
3345         /**
3346          * Determines if the expired <code>bundle</code> in the cache needs
3347          * to be reloaded based on the loading time given by
3348          * <code>loadTime</code> or some other criteria. The method returns
3349          * <code>true</code> if reloading is required; <code>false</code>
3350          * otherwise. <code>loadTime</code> is a millisecond offset since
3351          * the <a href="Calendar.html#Epoch"> <code>Calendar</code>
3352          * Epoch</a>.
3353          *
3354          * <p>
3355          * The calling <code>ResourceBundle.getBundle</code> factory method
3356          * calls this method on the <code>ResourceBundle.Control</code>
3357          * instance used for its current invocation, not on the instance
3358          * used in the invocation that originally loaded the resource
3359          * bundle.
3360          *
3361          * <p>The default implementation compares <code>loadTime</code> and
3362          * the last modified time of the source data of the resource
3363          * bundle. If it's determined that the source data has been modified
3364          * since <code>loadTime</code>, <code>true</code> is
3365          * returned. Otherwise, <code>false</code> is returned. This
3366          * implementation assumes that the given <code>format</code> is the
3367          * same string as its file suffix if it's not one of the default
3368          * formats, <code>"java.class"</code> or
3369          * <code>"java.properties"</code>.
3370          *
3371          * @param baseName
3372          *        the base bundle name of the resource bundle, a
3373          *        fully qualified class name
3374          * @param locale
3375          *        the locale for which the resource bundle
3376          *        should be instantiated
3377          * @param format
3378          *        the resource bundle format to be loaded
3379          * @param loader
3380          *        the <code>ClassLoader</code> to use to load the bundle
3381          * @param bundle
3382          *        the resource bundle instance that has been expired
3383          *        in the cache
3384          * @param loadTime
3385          *        the time when <code>bundle</code> was loaded and put
3386          *        in the cache
3387          * @return <code>true</code> if the expired bundle needs to be
3388          *        reloaded; <code>false</code> otherwise.
3389          * @exception NullPointerException
3390          *        if <code>baseName</code>, <code>locale</code>,
3391          *        <code>format</code>, <code>loader</code>, or
3392          *        <code>bundle</code> is <code>null</code>
3393          */
3394         public boolean needsReload(String baseName, Locale locale,
3395                                    String format, ClassLoader loader,
3396                                    ResourceBundle bundle, long loadTime) {
3397             if (bundle == null) {
3398                 throw new NullPointerException();
3399             }
3400             if (format.equals("java.class") || format.equals("java.properties")) {
3401                 format = format.substring(5);
3402             }
3403             boolean result = false;
3404             try {
3405                 String resourceName = toResourceName0(toBundleName(baseName, locale), format);
3406                 if (resourceName == null) {
3407                     return result;
3408                 }
3409                 URL url = loader.getResource(resourceName);
3410                 if (url != null) {
3411                     long lastModified = 0;
3412                     URLConnection connection = url.openConnection();
3413                     if (connection != null) {
3414                         // disable caches to get the correct data
3415                         connection.setUseCaches(false);
3416                         if (connection instanceof JarURLConnection) {
3417                             JarEntry ent = ((JarURLConnection)connection).getJarEntry();
3418                             if (ent != null) {
3419                                 lastModified = ent.getTime();
3420                                 if (lastModified == -1) {
3421                                     lastModified = 0;
3422                                 }
3423                             }
3424                         } else {
3425                             lastModified = connection.getLastModified();
3426                         }
3427                     }
3428                     result = lastModified >= loadTime;
3429                 }
3430             } catch (NullPointerException npe) {
3431                 throw npe;
3432             } catch (Exception e) {
3433                 // ignore other exceptions
3434             }
3435             return result;
3436         }
3437 
3438         /**
3439          * Converts the given <code>baseName</code> and <code>locale</code>
3440          * to the bundle name. This method is called from the default
3441          * implementation of the {@link #newBundle(String, Locale, String,
3442          * ClassLoader, boolean) newBundle} and {@link #needsReload(String,
3443          * Locale, String, ClassLoader, ResourceBundle, long) needsReload}
3444          * methods.
3445          *
3446          * <p>This implementation returns the following value:
3447          * <pre>
3448          *     baseName + "_" + language + "_" + script + "_" + country + "_" + variant
3449          * </pre>
3450          * where <code>language</code>, <code>script</code>, <code>country</code>,
3451          * and <code>variant</code> are the language, script, country, and variant
3452          * values of <code>locale</code>, respectively. Final component values that
3453          * are empty Strings are omitted along with the preceding '_'.  When the
3454          * script is empty, the script value is omitted along with the preceding '_'.
3455          * If all of the values are empty strings, then <code>baseName</code>
3456          * is returned.
3457          *
3458          * <p>For example, if <code>baseName</code> is
3459          * <code>"baseName"</code> and <code>locale</code> is
3460          * <code>Locale("ja",&nbsp;"",&nbsp;"XX")</code>, then
3461          * <code>"baseName_ja_&thinsp;_XX"</code> is returned. If the given
3462          * locale is <code>Locale("en")</code>, then
3463          * <code>"baseName_en"</code> is returned.
3464          *
3465          * <p>Overriding this method allows applications to use different
3466          * conventions in the organization and packaging of localized
3467          * resources.
3468          *
3469          * @param baseName
3470          *        the base name of the resource bundle, a fully
3471          *        qualified class name
3472          * @param locale
3473          *        the locale for which a resource bundle should be
3474          *        loaded
3475          * @return the bundle name for the resource bundle
3476          * @exception NullPointerException
3477          *        if <code>baseName</code> or <code>locale</code>
3478          *        is <code>null</code>
3479          * @see java.util.spi.AbstractResourceBundleProvider#toBundleName(String, Locale)
3480          */
3481         public String toBundleName(String baseName, Locale locale) {
3482             if (locale == Locale.ROOT) {
3483                 return baseName;
3484             }
3485 
3486             String language = locale.getLanguage();
3487             String script = locale.getScript();
3488             String country = locale.getCountry();
3489             String variant = locale.getVariant();
3490 
3491             if (language == "" && country == "" && variant == "") {
3492                 return baseName;
3493             }
3494 
3495             StringBuilder sb = new StringBuilder(baseName);
3496             sb.append('_');
3497             if (script != "") {
3498                 if (variant != "") {
3499                     sb.append(language).append('_').append(script).append('_').append(country).append('_').append(variant);
3500                 } else if (country != "") {
3501                     sb.append(language).append('_').append(script).append('_').append(country);
3502                 } else {
3503                     sb.append(language).append('_').append(script);
3504                 }
3505             } else {
3506                 if (variant != "") {
3507                     sb.append(language).append('_').append(country).append('_').append(variant);
3508                 } else if (country != "") {
3509                     sb.append(language).append('_').append(country);
3510                 } else {
3511                     sb.append(language);
3512                 }
3513             }
3514             return sb.toString();
3515 
3516         }
3517 
3518         /**
3519          * Converts the given <code>bundleName</code> to the form required
3520          * by the {@link ClassLoader#getResource ClassLoader.getResource}
3521          * method by replacing all occurrences of <code>'.'</code> in
3522          * <code>bundleName</code> with <code>'/'</code> and appending a
3523          * <code>'.'</code> and the given file <code>suffix</code>. For
3524          * example, if <code>bundleName</code> is
3525          * <code>"foo.bar.MyResources_ja_JP"</code> and <code>suffix</code>
3526          * is <code>"properties"</code>, then
3527          * <code>"foo/bar/MyResources_ja_JP.properties"</code> is returned.
3528          *
3529          * @param bundleName
3530          *        the bundle name
3531          * @param suffix
3532          *        the file type suffix
3533          * @return the converted resource name
3534          * @exception NullPointerException
3535          *         if <code>bundleName</code> or <code>suffix</code>
3536          *         is <code>null</code>
3537          */
3538         public final String toResourceName(String bundleName, String suffix) {
3539             StringBuilder sb = new StringBuilder(bundleName.length() + 1 + suffix.length());
3540             sb.append(bundleName.replace('.', '/')).append('.').append(suffix);
3541             return sb.toString();
3542         }
3543 
3544         private String toResourceName0(String bundleName, String suffix) {
3545             // application protocol check
3546             if (bundleName.contains("://")) {
3547                 return null;
3548             } else {
3549                 return toResourceName(bundleName, suffix);
3550             }
3551         }
3552     }
3553 
3554     @SuppressWarnings("unchecked")
3555     private static <T extends Throwable> void uncheckedThrow(Throwable t) throws T {
3556         if (t != null)
3557             throw (T)t;
3558         else
3559             throw new Error("Unknown Exception");
3560     }
3561 
3562     private static class SingleFormatControl extends Control {
3563         private static final Control PROPERTIES_ONLY
3564             = new SingleFormatControl(FORMAT_PROPERTIES);
3565 
3566         private static final Control CLASS_ONLY
3567             = new SingleFormatControl(FORMAT_CLASS);
3568 
3569         private final List<String> formats;
3570 
3571         protected SingleFormatControl(List<String> formats) {
3572             this.formats = formats;
3573         }
3574 
3575         public List<String> getFormats(String baseName) {
3576             if (baseName == null) {
3577                 throw new NullPointerException();
3578             }
3579             return formats;
3580         }
3581     }
3582 
3583     private static final class NoFallbackControl extends SingleFormatControl {
3584         private static final Control NO_FALLBACK
3585             = new NoFallbackControl(FORMAT_DEFAULT);
3586 
3587         private static final Control PROPERTIES_ONLY_NO_FALLBACK
3588             = new NoFallbackControl(FORMAT_PROPERTIES);
3589 
3590         private static final Control CLASS_ONLY_NO_FALLBACK
3591             = new NoFallbackControl(FORMAT_CLASS);
3592 
3593         protected NoFallbackControl(List<String> formats) {
3594             super(formats);
3595         }
3596 
3597         public Locale getFallbackLocale(String baseName, Locale locale) {
3598             if (baseName == null || locale == null) {
3599                 throw new NullPointerException();
3600             }
3601             return null;
3602         }
3603     }
3604 
3605     private static class ResourceBundleProviderHelper {
3606         /**
3607          * Returns a new ResourceBundle instance of the given bundleClass
3608          */
3609         static ResourceBundle newResourceBundle(Class<? extends ResourceBundle> bundleClass) {
3610             try {
3611                 @SuppressWarnings("unchecked")
3612                 Constructor<? extends ResourceBundle> ctor =
3613                     bundleClass.getConstructor();
3614                 if (!Modifier.isPublic(ctor.getModifiers())) {
3615                     return null;
3616                 }
3617                 // java.base may not be able to read the bundleClass's module.
3618                 PrivilegedAction<Void> pa = () -> { ctor.setAccessible(true); return null;};
3619                 AccessController.doPrivileged(pa);
3620                 try {
3621                     return ctor.newInstance((Object[]) null);
3622                 } catch (InvocationTargetException e) {
3623                     uncheckedThrow(e);
3624                 } catch (InstantiationException | IllegalAccessException e) {
3625                     throw new InternalError(e);
3626                 }
3627             } catch (NoSuchMethodException e) {
3628                 throw new InternalError(e);
3629             }
3630             return null;
3631         }
3632 
3633         /**
3634          * Loads a {@code ResourceBundle} of the given {@code bundleName} local to
3635          * the given {@code module}. If not found, search the bundle class
3636          * that is visible from the module's class loader.
3637          *
3638          * The caller module is used for access check only.
3639          */
3640         static ResourceBundle loadResourceBundle(Module callerModule,
3641                                                  Module module,
3642                                                  String baseName,
3643                                                  Locale locale)
3644         {
3645             String bundleName = Control.INSTANCE.toBundleName(baseName, locale);
3646             try {
3647                 PrivilegedAction<Class<?>> pa = () -> Class.forName(module, bundleName);
3648                 Class<?> c = AccessController.doPrivileged(pa, null, GET_CLASSLOADER_PERMISSION);
3649                 trace("local in %s %s caller %s: %s%n", module, bundleName, callerModule, c);
3650 
3651                 if (c == null) {
3652                     // if not found from the given module, locate resource bundle
3653                     // that is visible to the module's class loader
3654                     ClassLoader loader = getLoader(module);
3655                     if (loader != null) {
3656                         c = Class.forName(bundleName, false, loader);
3657                     } else {
3658                         c = BootLoader.loadClassOrNull(bundleName);
3659                     }
3660                     trace("loader for %s %s caller %s: %s%n", module, bundleName, callerModule, c);
3661                 }
3662 
3663                 if (c != null && ResourceBundle.class.isAssignableFrom(c)) {
3664                     @SuppressWarnings("unchecked")
3665                     Class<ResourceBundle> bundleClass = (Class<ResourceBundle>) c;
3666                     Module m = bundleClass.getModule();
3667                     if (!isAccessible(callerModule, m, bundleClass.getPackageName())) {
3668                         trace("   %s does not have access to %s/%s%n", callerModule,
3669                               m.getName(), bundleClass.getPackageName());
3670                         return null;
3671                     }
3672 
3673                     return newResourceBundle(bundleClass);
3674                 }
3675             } catch (ClassNotFoundException e) {}
3676             return null;
3677         }
3678 
3679         /**
3680          * Tests if resources of the given package name from the given module are
3681          * open to the caller module.
3682          */
3683         static boolean isAccessible(Module callerModule, Module module, String pn) {
3684             if (!module.isNamed() || callerModule == module)
3685                 return true;
3686 
3687             return module.isOpen(pn, callerModule);
3688         }
3689 
3690         /**
3691          * Loads properties of the given {@code bundleName} local in the given
3692          * {@code module}.  If the .properties is not found or not open
3693          * to the caller module to access, it will find the resource that
3694          * is visible to the module's class loader.
3695          *
3696          * The caller module is used for access check only.
3697          */
3698         static ResourceBundle loadPropertyResourceBundle(Module callerModule,
3699                                                          Module module,
3700                                                          String baseName,
3701                                                          Locale locale)
3702             throws IOException
3703         {
3704             String bundleName = Control.INSTANCE.toBundleName(baseName, locale);
3705 
3706             PrivilegedAction<InputStream> pa = () -> {
3707                 try {
3708                     String resourceName = Control.INSTANCE
3709                         .toResourceName0(bundleName, "properties");
3710                     if (resourceName == null) {
3711                         return null;
3712                     }
3713                     trace("local in %s %s caller %s%n", module, resourceName, callerModule);
3714 
3715                     // if the package is in the given module but not opened
3716                     // locate it from the given module first.
3717                     String pn = toPackageName(bundleName);
3718                     trace("   %s/%s is accessible to %s : %s%n",
3719                             module.getName(), pn, callerModule,
3720                             isAccessible(callerModule, module, pn));
3721                     if (isAccessible(callerModule, module, pn)) {
3722                         InputStream in = module.getResourceAsStream(resourceName);
3723                         if (in != null) {
3724                             return in;
3725                         }
3726                     }
3727 
3728                     ClassLoader loader = module.getClassLoader();
3729                     trace("loader for %s %s caller %s%n", module, resourceName, callerModule);
3730 
3731                     try {
3732                         if (loader != null) {
3733                             return loader.getResourceAsStream(resourceName);
3734                         } else {
3735                             URL url = BootLoader.findResource(resourceName);
3736                             if (url != null) {
3737                                 return url.openStream();
3738                             }
3739                         }
3740                     } catch (Exception e) {}
3741                     return null;
3742 
3743                 } catch (IOException e) {
3744                     throw new UncheckedIOException(e);
3745                 }
3746             };
3747 
3748             try (InputStream stream = AccessController.doPrivileged(pa)) {
3749                 if (stream != null) {
3750                     return new PropertyResourceBundle(stream);
3751                 } else {
3752                     return null;
3753                 }
3754             } catch (UncheckedIOException e) {
3755                 throw e.getCause();
3756             }
3757         }
3758 
3759         private static String toPackageName(String bundleName) {
3760             int i = bundleName.lastIndexOf('.');
3761             return i != -1 ? bundleName.substring(0, i) : "";
3762         }
3763 
3764     }
3765 
3766     private static final boolean TRACE_ON = Boolean.valueOf(
3767         GetPropertyAction.privilegedGetProperty("resource.bundle.debug", "false"));
3768 
3769     private static void trace(String format, Object... params) {
3770         if (TRACE_ON)
3771             System.out.format(format, params);
3772     }
3773 }