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third-party-mirror/openjdk/jdk25u/refs/heads/master/./src/java.base/share/classes/java/util/ResourceBundle.java
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/*
* Copyright (c) 1996, 2025, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
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/*
* (C) Copyright Taligent, Inc. 1996, 1997 - All Rights Reserved
* (C) Copyright IBM Corp. 1996 - 1999 - All Rights Reserved
*
* The original version of this source code and documentation
* is copyrighted and owned by Taligent, Inc., a wholly-owned
* subsidiary of IBM. These materials are provided under terms
* of a License Agreement between Taligent and Sun. This technology
* is protected by multiple US and International patents.
*
* This notice and attribution to Taligent may not be removed.
* Taligent is a registered trademark of Taligent, Inc.
*
*/
package java.util;
import java.io.IOException;
import java.io.InputStream;
import java.lang.ref.Reference;
import java.lang.ref.ReferenceQueue;
import java.lang.ref.SoftReference;
import java.lang.ref.WeakReference;
import java.lang.reflect.Constructor;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Modifier;
import java.net.JarURLConnection;
import java.net.URL;
import java.net.URLConnection;
import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.ConcurrentMap;
import java.util.jar.JarEntry;
import java.util.spi.ResourceBundleControlProvider;
import java.util.spi.ResourceBundleProvider;
import java.util.stream.Stream;
import jdk.internal.loader.BootLoader;
import jdk.internal.access.JavaUtilResourceBundleAccess;
import jdk.internal.access.SharedSecrets;
import jdk.internal.reflect.CallerSensitive;
import jdk.internal.reflect.Reflection;
import jdk.internal.util.ReferencedKeyMap;
import sun.util.locale.BaseLocale;
import sun.util.resources.Bundles;
/**
*
* Resource bundles contain locale-specific objects. When your program needs a
* locale-specific resource, a {@code String} for example, your program can
* load it from the resource bundle that is appropriate for the current user's
* locale. In this way, you can write program code that is largely independent
* of the user's locale isolating most, if not all, of the locale-specific
* information in resource bundles.
*
* <p>
* This allows you to write programs that can:
* <UL>
* <LI> be easily localized, or translated, into different languages
* <LI> handle multiple locales at once
* <LI> be easily modified later to support even more locales
* </UL>
*
* <P>
* Resource bundles belong to families whose members share a common base
* name, but whose names also have additional components that identify
* their locales. For example, the base name of a family of resource
* bundles might be "MyResources". The family should have a default
* resource bundle which simply has the same name as its family -
* "MyResources" - and will be used as the bundle of last resort if a
* specific locale is not supported. The family can then provide as
* many locale-specific members as needed, for example a German one
* named "MyResources_de".
*
* <P>
* Each resource bundle in a family contains the same items, but the items have
* been translated for the locale represented by that resource bundle.
* For example, both "MyResources" and "MyResources_de" may have a
* {@code String} that's used on a button for canceling operations.
* In "MyResources" the {@code String} may contain "Cancel" and in
* "MyResources_de" it may contain "Abbrechen".
*
* <P>
* If there are different resources for different countries, you
* can make specializations: for example, "MyResources_de_CH" contains objects for
* the German language (de) in Switzerland (CH). If you want to only
* modify some of the resources
* in the specialization, you can do so.
*
* <P>
* When your program needs a locale-specific object, it loads
* the {@code ResourceBundle} class using the
* {@link #getBundle(java.lang.String, java.util.Locale) getBundle}
* method:
* {@snippet lang=java :
* ResourceBundle myResources =
* ResourceBundle.getBundle("MyResources", currentLocale);
* }
*
* <P>
* Resource bundles contain key/value pairs. The keys uniquely
* identify a locale-specific object in the bundle. Here's an
* example of a {@code ListResourceBundle} that contains
* two key/value pairs:
* {@snippet lang=java :
* public class MyResources extends ListResourceBundle {
* protected Object[][] getContents() {
* return new Object[][] {
* // LOCALIZE THE SECOND STRING OF EACH ARRAY (e.g., "OK")
* {"OkKey", "OK"},
* {"CancelKey", "Cancel"},
* // END OF MATERIAL TO LOCALIZE
* };
* }
* }
* }
* Keys are always {@code String}s.
* In this example, the keys are "OkKey" and "CancelKey".
* In the above example, the values
* are also {@code String}s--"OK" and "Cancel"--but
* they don't have to be. The values can be any type of object.
*
* <P>
* You retrieve an object from resource bundle using the appropriate
* getter method. Because "OkKey" and "CancelKey"
* are both strings, you would use {@code getString} to retrieve them:
* {@snippet lang=java :
* button1 = new Button(myResources.getString("OkKey"));
* button2 = new Button(myResources.getString("CancelKey"));
* }
* The getter methods all require the key as an argument and return
* the object if found. If the object is not found, the getter method
* throws a {@code MissingResourceException}.
*
* <P>
* Besides {@code getString}, {@code ResourceBundle} also provides
* a method for getting string arrays, {@code getStringArray},
* as well as a generic {@code getObject} method for any other
* type of object. When using {@code getObject}, you'll
* have to cast the result to the appropriate type. For example:
* {@snippet lang=java :
* int[] myIntegers = (int[]) myResources.getObject("intList");
* }
*
* <P>
* The Java Platform provides two subclasses of {@code ResourceBundle},
* {@code ListResourceBundle} and {@code PropertyResourceBundle},
* that provide a fairly simple way to create resources.
* As you saw briefly in a previous example, {@code ListResourceBundle}
* manages its resource as a list of key/value pairs.
* {@code PropertyResourceBundle} uses a properties file to manage
* its resources.
*
* <p>
* If {@code ListResourceBundle} or {@code PropertyResourceBundle}
* do not suit your needs, you can write your own {@code ResourceBundle}
* subclass. Your subclasses must override two methods: {@code handleGetObject}
* and {@code getKeys()}.
*
* <p>
* The implementation of a {@code ResourceBundle} subclass must be thread-safe
* if it's simultaneously used by multiple threads. The default implementations
* of the non-abstract methods in this class, and the methods in the direct
* known concrete subclasses {@code ListResourceBundle} and
* {@code PropertyResourceBundle} are thread-safe.
*
* <h2><a id="resource-bundle-modules">Resource Bundles and Named Modules</a></h2>
*
* Resource bundles can be deployed in modules in the following ways:
*
* <h3>Resource bundles together with an application</h3>
*
* Resource bundles can be deployed together with an application in the same
* module. In that case, the resource bundles are loaded
* by code in the module by calling the {@link #getBundle(String)}
* or {@link #getBundle(String, Locale)} method.
*
* <h3><a id="service-providers">Resource bundles as service providers</a></h3>
*
* Resource bundles can be deployed in one or more <em>service provider modules</em>
* and they can be located using {@link ServiceLoader}.
* A {@linkplain ResourceBundleProvider service} interface or class must be
* defined. The caller module declares that it uses the service, the service
* provider modules declare that they provide implementations of the service.
* Refer to {@link ResourceBundleProvider} for developing resource bundle
* services and deploying resource bundle providers.
* The module obtaining the resource bundle can be a resource bundle
* provider itself; in which case this module only locates the resource bundle
* via service provider mechanism.
*
* <p>A {@linkplain ResourceBundleProvider resource bundle provider} can
* provide resource bundles in any format such XML which replaces the need
* of {@link Control ResourceBundle.Control}.
*
* <h3><a id="other-modules">Resource bundles in other modules and class path</a></h3>
*
* Resource bundles in a named module may be <em>encapsulated</em> so that
* it cannot be located by code in other modules. Resource bundles
* in unnamed modules and class path are open for any module to access.
* Resource bundle follows the resource encapsulation rules as specified
* in {@link Module#getResourceAsStream(String)}.
*
* <p>The {@code getBundle} factory methods with no {@code Control} parameter
* locate and load resource bundles from
* {@linkplain ResourceBundleProvider service providers}.
* It may continue the search as if calling {@link Module#getResourceAsStream(String)}
* to find the named resource from a given module and calling
* {@link ClassLoader#getResourceAsStream(String)}; refer to
* the specification of the {@code getBundle} method for details.
* Only non-encapsulated resource bundles of "{@code java.class}"
* or "{@code java.properties}" format are searched.
*
* <p>If the caller module is a {@linkplain
* ResourceBundleProvider##obtain-resource-bundle resource bundle
* provider}, it does not fall back to the class loader search.
*
* <p>
* In cases where the {@code getBundle} factory method is called from a context
* where there is no caller frame on the stack (e.g. when called directly from
* a JNI attached thread), the caller module is default to the unnamed module for the
* {@linkplain ClassLoader#getSystemClassLoader system class loader}.
*
* <h3>Resource bundles in automatic modules</h3>
*
* A common format of resource bundles is in {@linkplain PropertyResourceBundle
* .properties} file format. Typically {@code .properties} resource bundles
* are packaged in a JAR file. Resource bundle only JAR file can be readily
* deployed as an {@linkplain java.lang.module.ModuleFinder##automatic-modules
* automatic module}. For example, if the JAR file contains the
* entry "{@code p/q/Foo_ja.properties}" and no {@code .class} entry,
* when resolved and defined as an automatic module, no package is derived
* for this module. This allows resource bundles in {@code .properties}
* format packaged in one or more JAR files that may contain entries
* in the same directory and can be resolved successfully as
* automatic modules.
*
* <h3>ResourceBundle.Control</h3>
*
* The {@link ResourceBundle.Control} class provides information necessary
* to perform the bundle loading process by the {@code getBundle}
* factory methods that take a {@code ResourceBundle.Control}
* instance. You can implement your own subclass in order to enable
* non-standard resource bundle formats, change the search strategy, or
* define caching parameters. Refer to the descriptions of the class and the
* {@link #getBundle(String, Locale, ClassLoader, Control) getBundle}
* factory method for details.
*
* <p> {@link ResourceBundle.Control} is designed for an application deployed
* in an unnamed module, for example to support resource bundles in
* non-standard formats or package localized resources in a non-traditional
* convention. {@link ResourceBundleProvider} is the replacement for
* {@code ResourceBundle.Control} when migrating to modules.
* {@code UnsupportedOperationException} will be thrown when a factory
* method that takes the {@code ResourceBundle.Control} parameter is called.
*
* <p><a id="modify_default_behavior">For the {@code getBundle} factory</a>
* methods that take no {@link Control} instance, their <a
* href="#default_behavior"> default behavior</a> of resource bundle loading
* can be modified with custom {@link
* ResourceBundleControlProvider} implementations.
* If any of the
* providers provides a {@link Control} for the given base name, that {@link
* Control} will be used instead of the default {@link Control}. If there is
* more than one service provider for supporting the same base name,
* the first one returned from {@link ServiceLoader} will be used.
* A custom {@link Control} implementation is ignored by named modules.
*
* <h2>Cache Management</h2>
*
* Resource bundle instances created by the {@code getBundle} factory
* methods are cached by default, and the factory methods return the same
* resource bundle instance multiple times if it has been
* cached. {@code getBundle} clients may clear the cache, manage the
* lifetime of cached resource bundle instances using time-to-live values,
* or specify not to cache resource bundle instances. Refer to the
* descriptions of the {@linkplain #getBundle(String, Locale, ClassLoader,
* Control) {@code getBundle} factory method}, {@link
* #clearCache(ClassLoader) clearCache}, {@link
* Control#getTimeToLive(String, Locale)
* ResourceBundle.Control.getTimeToLive}, and {@link
* Control#needsReload(String, Locale, String, ClassLoader, ResourceBundle,
* long) ResourceBundle.Control.needsReload} for details.
*
* <h2>Example</h2>
*
* The following is a very simple example of a {@code ResourceBundle}
* subclass, {@code MyResources}, that manages two resources (for a larger number of
* resources you would probably use a {@code Map}).
* Notice that you don't need to supply a value if
* a "parent-level" {@code ResourceBundle} handles the same
* key with the same value (as for the okKey below).
* {@snippet lang=java :
* // default (English language, United States)
* public class MyResources extends ResourceBundle {
* public Object handleGetObject(String key) {
* if (key.equals("okKey")) {
* return "Ok";
* }
* if (key.equals("cancelKey")) {
* return "Cancel";
* }
* return null;
* }
*
* public Enumeration<String> getKeys() {
* return Collections.enumeration(keySet());
* }
*
* // Overrides handleKeySet() so that the getKeys() implementation
* // can rely on the keySet() value.
* protected Set<String> handleKeySet() {
* return new HashSet<String>(Arrays.asList("okKey", "cancelKey"));
* }
* }
*
* // German language
* public class MyResources_de extends MyResources {
* public Object handleGetObject(String key) {
* // don't need okKey, since parent level handles it.
* if (key.equals("cancelKey")) {
* return "Abbrechen";
* }
* return null;
* }
*
* protected Set<String> handleKeySet() {
* return new HashSet<String>(Arrays.asList("cancelKey"));
* }
* }
* }
* You do not have to restrict yourself to using a single family of
* {@code ResourceBundle}s. For example, you could have a set of bundles for
* exception messages, {@code ExceptionResources}
* ({@code ExceptionResources_fr}, {@code ExceptionResources_de}, ...),
* and one for widgets, {@code WidgetResource} ({@code WidgetResources_fr},
* {@code WidgetResources_de}, ...); breaking up the resources however you like.
*
* @see ListResourceBundle
* @see PropertyResourceBundle
* @see MissingResourceException
* @see ResourceBundleProvider
* @since 1.1
*/
public abstract class ResourceBundle {
/** initial size of the bundle cache */
private static final int INITIAL_CACHE_SIZE = 32;
static {
SharedSecrets.setJavaUtilResourceBundleAccess(
new JavaUtilResourceBundleAccess() {
@Override
public void setParent(ResourceBundle bundle,
ResourceBundle parent) {
bundle.setParent(parent);
}
@Override
public ResourceBundle getParent(ResourceBundle bundle) {
return bundle.parent;
}
@Override
public void setLocale(ResourceBundle bundle, Locale locale) {
bundle.locale = locale;
}
@Override
public void setName(ResourceBundle bundle, String name) {
bundle.name = name;
}
@Override
public ResourceBundle getBundle(String baseName, Locale locale, Module module) {
// use the given module as the caller to bypass the access check
return getBundleImpl(module, module,
baseName, locale,
getDefaultControl(module, baseName));
}
@Override
public ResourceBundle newResourceBundle(Class<? extends ResourceBundle> bundleClass) {
return ResourceBundleProviderHelper.newResourceBundle(bundleClass);
}
});
}
/** constant indicating that no resource bundle exists */
private static final ResourceBundle NONEXISTENT_BUNDLE = new ResourceBundle() {
public Enumeration<String> getKeys() { return null; }
protected Object handleGetObject(String key) { return null; }
public String toString() { return "NONEXISTENT_BUNDLE"; }
};
/**
* The cache is a map from cache keys (with bundle base name, locale, and
* class loader) to either a resource bundle or NONEXISTENT_BUNDLE wrapped by a
* BundleReference.
*
* The cache is a ConcurrentMap, allowing the cache to be searched
* concurrently by multiple threads. This will also allow the cache keys
* to be reclaimed along with the ClassLoaders they reference.
*
* This variable would be better named "cache", but we keep the old
* name for compatibility with some workarounds for bug 4212439.
*/
private static final ConcurrentMap<CacheKey, BundleReference> cacheList
= new ConcurrentHashMap<>(INITIAL_CACHE_SIZE);
/**
* Queue for reference objects referring to class loaders or bundles.
*/
private static final ReferenceQueue<Object> referenceQueue = new ReferenceQueue<>();
/**
* Returns the base name of this bundle, if known, or {@code null} if unknown.
*
* If not null, then this is the value of the {@code baseName} parameter
* that was passed to the {@code ResourceBundle.getBundle(...)} method
* when the resource bundle was loaded.
*
* @return The base name of the resource bundle, as provided to and expected
* by the {@code ResourceBundle.getBundle(...)} methods.
*
* @see #getBundle(java.lang.String, java.util.Locale, java.lang.ClassLoader)
*
* @since 1.8
*/
public String getBaseBundleName() {
return name;
}
/**
* The parent bundle of this bundle.
* The parent bundle is searched by {@link #getObject getObject}
* when this bundle does not contain a particular resource.
*/
protected ResourceBundle parent = null;
/**
* The locale for this bundle.
*/
private Locale locale = null;
/**
* The base bundle name for this bundle.
*/
private String name;
/**
* The flag indicating this bundle has expired in the cache.
*/
private volatile boolean expired;
/**
* The back link to the cache key. null if this bundle isn't in
* the cache (yet) or has expired.
*/
private volatile CacheKey cacheKey;
/**
* A Set of the keys contained only in this ResourceBundle.
*/
private volatile Set<String> keySet;
/**
* Sole constructor. (For invocation by subclass constructors, typically
* implicit.)
*/
public ResourceBundle() {
}
/**
* Gets a string for the given key from this resource bundle or one of its parents.
* Calling this method is equivalent to calling
* {@snippet lang=java :
* // @link substring="getObject" target="#getObject(java.lang.String)" :
* (String) getObject(key);
* }
*
* @param key the key for the desired string
* @throws NullPointerException if {@code key} is {@code null}
* @throws MissingResourceException if no object for the given key can be found
* @throws ClassCastException if the object found for the given key is not a string
* @return the string for the given key
*/
public final String getString(String key) {
return (String) getObject(key);
}
/**
* Gets a string array for the given key from this resource bundle or one of its parents.
* Calling this method is equivalent to calling
* {@snippet lang=java :
* // @link substring="getObject" target="#getObject(java.lang.String)" :
* (String[]) getObject(key);
* }
*
* @param key the key for the desired string array
* @throws NullPointerException if {@code key} is {@code null}
* @throws MissingResourceException if no object for the given key can be found
* @throws ClassCastException if the object found for the given key is not a string array
* @return the string array for the given key
*/
public final String[] getStringArray(String key) {
return (String[]) getObject(key);
}
/**
* Gets an object for the given key from this resource bundle or one of its parents.
* This method first tries to obtain the object from this resource bundle using
* {@link #handleGetObject(java.lang.String) handleGetObject}.
* If not successful, and the parent resource bundle is not null,
* it calls the parent's {@code getObject} method.
* If still not successful, it throws a MissingResourceException.
*
* @param key the key for the desired object
* @throws NullPointerException if {@code key} is {@code null}
* @throws MissingResourceException if no object for the given key can be found
* @return the object for the given key
*/
public final Object getObject(String key) {
Object obj = handleGetObject(key);
if (obj == null) {
if (parent != null) {
obj = parent.getObject(key);
}
if (obj == null) {
throw new MissingResourceException("Can't find resource for bundle "
+this.getClass().getName()
+", key "+key,
this.getClass().getName(),
key);
}
}
return obj;
}
/**
* Returns the locale of this resource bundle. This method can be used after a
* call to getBundle() to determine whether the resource bundle returned really
* corresponds to the requested locale or is a fallback.
*
* @return the locale of this resource bundle
*/
public Locale getLocale() {
return locale;
}
private static ClassLoader getLoader(Module module) {
return module.getClassLoader();
}
/**
* @param module a non-null-screened module form the {@link CacheKey#getModule()}.
* @return the ClassLoader to use in {@link Control#needsReload}
* and {@link Control#newBundle}
*/
private static ClassLoader getLoaderForControl(Module module) {
ClassLoader loader = getLoader(module);
return loader == null ? ClassLoader.getPlatformClassLoader() : loader;
}
/**
* Sets the parent bundle of this bundle.
* The parent bundle is searched by {@link #getObject getObject}
* when this bundle does not contain a particular resource.
*
* @param parent this bundle's parent bundle.
*/
protected void setParent(ResourceBundle parent) {
assert parent != NONEXISTENT_BUNDLE;
this.parent = parent;
}
/**
* Key used for cached resource bundles. The key checks the base
* name, the locale, the bundle module, and the caller module
* to determine if the resource is a match to the requested one.
* The base name, the locale and both modules must have a non-null value.
*/
private static final class CacheKey {
// These four are the actual keys for lookup in Map.
private final String name;
private volatile Locale locale;
private final KeyElementReference<Module> moduleRef;
private final KeyElementReference<Module> callerRef;
// this is the part of hashCode that pertains to module and callerModule
// which can be GCed..
private final int modulesHash;
// bundle format which is necessary for calling
// Control.needsReload().
private volatile String format;
// These time values are in CacheKey so that NONEXISTENT_BUNDLE
// doesn't need to be cloned for caching.
// The time when the bundle has been loaded
private volatile long loadTime;
// The time when the bundle expires in the cache, or either
// Control.TTL_DONT_CACHE or Control.TTL_NO_EXPIRATION_CONTROL.
private volatile long expirationTime;
// Placeholder for an error report by a Throwable
private volatile Throwable cause;
// ResourceBundleProviders for loading ResourceBundles
private volatile ServiceLoader<ResourceBundleProvider> providers;
private volatile boolean providersChecked;
// Boolean.TRUE if the factory method caller provides a ResourceBundleProvier.
private volatile Boolean callerHasProvider;
CacheKey(String baseName, Locale locale, Module module, Module caller) {
Objects.requireNonNull(module);
Objects.requireNonNull(caller);
this.name = baseName;
this.locale = locale;
this.moduleRef = new KeyElementReference<>(module, referenceQueue, this);
this.callerRef = new KeyElementReference<>(caller, referenceQueue, this);
this.modulesHash = module.hashCode() ^ caller.hashCode();
}
CacheKey(CacheKey src) {
// Create References to src's modules
this.moduleRef = new KeyElementReference<>(
Objects.requireNonNull(src.getModule()), referenceQueue, this);
this.callerRef = new KeyElementReference<>(
Objects.requireNonNull(src.getCallerModule()), referenceQueue, this);
// Copy fields from src. ResourceBundleProviders related fields
// and "cause" should not be copied.
this.name = src.name;
this.locale = src.locale;
this.modulesHash = src.modulesHash;
this.format = src.format;
this.loadTime = src.loadTime;
this.expirationTime = src.expirationTime;
}
String getName() {
return name;
}
Locale getLocale() {
return locale;
}
CacheKey setLocale(Locale locale) {
this.locale = locale;
return this;
}
Module getModule() {
return moduleRef.get();
}
Module getCallerModule() {
return callerRef.get();
}
ServiceLoader<ResourceBundleProvider> getProviders() {
if (!providersChecked) {
providers = getServiceLoader(getModule(), name);
providersChecked = true;
}
return providers;
}
boolean hasProviders() {
return getProviders() != null;
}
boolean callerHasProvider() {
return callerHasProvider == Boolean.TRUE;
}
@Override
public boolean equals(Object other) {
if (this == other) {
return true;
}
if (other instanceof CacheKey otherEntry) {
//quick check to see if they are not equal
if (modulesHash != otherEntry.modulesHash) {
return false;
}
//are the names the same?
if (!name.equals(otherEntry.name)) {
return false;
}
// are the locales the same?
if (!locale.equals(otherEntry.locale)) {
return false;
}
// are modules and callerModules the same and non-null?
Module module = getModule();
Module caller = getCallerModule();
return ((module != null) && (module.equals(otherEntry.getModule())) &&
(caller != null) && (caller.equals(otherEntry.getCallerModule())));
}
return false;
}
@Override
public int hashCode() {
return (name.hashCode() << 3) ^ locale.hashCode() ^ modulesHash;
}
String getFormat() {
return format;
}
void setFormat(String format) {
this.format = format;
}
private void setCause(Throwable cause) {
if (this.cause == null) {
this.cause = cause;
} else {
// Override the cause if the previous one is
// ClassNotFoundException.
if (this.cause instanceof ClassNotFoundException) {
this.cause = cause;
}
}
}
private Throwable getCause() {
return cause;
}
@Override
public String toString() {
String l = locale.toString();
if (l.isEmpty()) {
if (!locale.getVariant().isEmpty()) {
l = "__" + locale.getVariant();
} else {
l = "\"\"";
}
}
return "CacheKey[" + name +
", locale=" + l +
", module=" + getModule() +
", callerModule=" + getCallerModule() +
", format=" + format +
"]";
}
}
/**
* The common interface to get a CacheKey in LoaderReference and
* BundleReference.
*/
private static interface CacheKeyReference {
public CacheKey getCacheKey();
}
/**
* References to a CacheKey element as a WeakReference so that it can be
* garbage collected when nobody else is using it.
*/
private static class KeyElementReference<T> extends WeakReference<T>
implements CacheKeyReference {
private final CacheKey cacheKey;
KeyElementReference(T referent, ReferenceQueue<Object> q, CacheKey key) {
super(referent, q);
cacheKey = key;
}
@Override
public CacheKey getCacheKey() {
return cacheKey;
}
}
/**
* References to bundles are soft references so that they can be garbage
* collected when they have no hard references.
*/
private static class BundleReference extends SoftReference<ResourceBundle>
implements CacheKeyReference {
private final CacheKey cacheKey;
BundleReference(ResourceBundle referent, ReferenceQueue<Object> q, CacheKey key) {
super(referent, q);
cacheKey = key;
}
@Override
public CacheKey getCacheKey() {
return cacheKey;
}
}
/**
* Gets a resource bundle using the specified base name, the default locale,
* and the caller module. Calling this method is equivalent to calling
* {@snippet lang=java :
* getBundle(baseName, Locale.getDefault(), callerModule);
* }
*
* @param baseName the base name of the resource bundle, a fully qualified class name
* @throws java.lang.NullPointerException
* if {@code baseName} is {@code null}
* @throws MissingResourceException
* if no resource bundle for the specified base name can be found
* @return a resource bundle for the given base name and the default locale
*
* @see <a href="#default_behavior">Resource Bundle Search and Loading Strategy</a>
* @see <a href="#resource-bundle-modules">Resource Bundles and Named Modules</a>
*/
@CallerSensitive
public static final ResourceBundle getBundle(String baseName)
{
Class<?> caller = Reflection.getCallerClass();
return getBundleImpl(baseName, Locale.getDefault(),
caller, getDefaultControl(caller, baseName));
}
/**
* Returns a resource bundle using the specified base name, the
* default locale and the specified control. Calling this method
* is equivalent to calling
* {@snippet lang=java :
* getBundle(baseName, Locale.getDefault(),
* this.getClass().getClassLoader(), control);
* }
* except that {@code getClassLoader()} is run with the security
* privileges of {@code ResourceBundle}. See {@link
* #getBundle(String, Locale, ClassLoader, Control) getBundle} for the
* complete description of the resource bundle loading process with a
* {@code ResourceBundle.Control}.
*
* @param baseName
* the base name of the resource bundle, a fully qualified class
* name
* @param control
* the control which gives information for the resource bundle
* loading process
* @return a resource bundle for the given base name and the default locale
* @throws NullPointerException
* if {@code baseName} or {@code control} is
* {@code null}
* @throws MissingResourceException
* if no resource bundle for the specified base name can be found
* @throws IllegalArgumentException
* if the given {@code control} doesn't perform properly
* (e.g., {@code control.getCandidateLocales} returns null.)
* Note that validation of {@code control} is performed as
* needed.
* @throws UnsupportedOperationException
* if this method is called in a named module
* @since 1.6
*/
@CallerSensitive
public static final ResourceBundle getBundle(String baseName,
Control control) {
Class<?> caller = Reflection.getCallerClass();
Locale targetLocale = Locale.getDefault();
checkNamedModule(caller);
return getBundleImpl(baseName, targetLocale, caller, control);
}
/**
* Gets a resource bundle using the specified base name and locale,
* and the caller module. Calling this method is equivalent to calling
* {@snippet lang=java :
* getBundle(baseName, locale, callerModule);
* }
*
* @param baseName
* the base name of the resource bundle, a fully qualified class name
* @param locale
* the locale for which a resource bundle is desired
* @throws NullPointerException
* if {@code baseName} or {@code locale} is {@code null}
* @throws MissingResourceException
* if no resource bundle for the specified base name can be found
* @return a resource bundle for the given base name and locale
*
* @see <a href="#default_behavior">Resource Bundle Search and Loading Strategy</a>
* @see <a href="#resource-bundle-modules">Resource Bundles and Named Modules</a>
*/
@CallerSensitive
public static final ResourceBundle getBundle(String baseName,
Locale locale)
{
Class<?> caller = Reflection.getCallerClass();
return getBundleImpl(baseName, locale,
caller, getDefaultControl(caller, baseName));
}
/**
* Gets a resource bundle using the specified base name and the default locale
* on behalf of the specified module. This method is equivalent to calling
* {@snippet lang=java :
* getBundle(baseName, Locale.getDefault(), module);
* }
*
* @param baseName the base name of the resource bundle,
* a fully qualified class name
* @param module the module for which the resource bundle is searched
* @throws NullPointerException
* if {@code baseName} or {@code module} is {@code null}
* @throws MissingResourceException
* if no resource bundle for the specified base name can be found in the
* specified module
* @return a resource bundle for the given base name and the default locale
* @since 9
* @see ResourceBundleProvider
* @see <a href="#default_behavior">Resource Bundle Search and Loading Strategy</a>
* @see <a href="#resource-bundle-modules">Resource Bundles and Named Modules</a>
*/
@CallerSensitive
public static ResourceBundle getBundle(String baseName, Module module) {
return getBundleFromModule(Reflection.getCallerClass(), module, baseName,
Locale.getDefault(),
getDefaultControl(module, baseName));
}
/**
* Gets a resource bundle using the specified base name and locale
* on behalf of the specified module.
*
* <p> Resource bundles in named modules may be encapsulated. When
* the resource bundle is loaded from a
* {@linkplain ResourceBundleProvider service provider}, the caller module
* must have an appropriate <i>uses</i> clause in its <i>module descriptor</i>
* to declare that the module uses of {@link ResourceBundleProvider}
* for the named resource bundle.
* Otherwise, it will load the resource bundles that are local in the
* given module as if calling {@link Module#getResourceAsStream(String)}
* or that are visible to the class loader of the given module
* as if calling {@link ClassLoader#getResourceAsStream(String)}.
* When the resource bundle is loaded from the specified module, it is
* subject to the encapsulation rules specified by
* {@link Module#getResourceAsStream Module.getResourceAsStream}.
*
* <p>
* If the given {@code module} is an unnamed module, then this method is
* equivalent to calling {@link #getBundle(String, Locale, ClassLoader)
* getBundle(baseName, targetLocale, module.getClassLoader()} to load
* resource bundles that are visible to the class loader of the given
* unnamed module. Custom {@link java.util.spi.ResourceBundleControlProvider}
* implementations, if present, will only be invoked if the specified
* module is an unnamed module.
*
* @param baseName the base name of the resource bundle,
* a fully qualified class name
* @param targetLocale the locale for which a resource bundle is desired
* @param module the module for which the resource bundle is searched
* @throws NullPointerException
* if {@code baseName}, {@code targetLocale}, or {@code module} is
* {@code null}
* @throws MissingResourceException
* if no resource bundle for the specified base name and locale can
* be found in the specified {@code module}
* @return a resource bundle for the given base name and locale in the module
* @since 9
* @see <a href="#default_behavior">Resource Bundle Search and Loading Strategy</a>
* @see <a href="#resource-bundle-modules">Resource Bundles and Named Modules</a>
*/
@CallerSensitive
public static ResourceBundle getBundle(String baseName, Locale targetLocale, Module module) {
return getBundleFromModule(Reflection.getCallerClass(), module, baseName, targetLocale,
getDefaultControl(module, baseName));
}
/**
* Returns a resource bundle using the specified base name, target
* locale and control, and the caller's class loader. Calling this
* method is equivalent to calling
* {@snippet lang=java :
* getBundle(baseName, targetLocale, this.getClass().getClassLoader(),
* control);
* }
* except that {@code getClassLoader()} is run with the security
* privileges of {@code ResourceBundle}. See {@link
* #getBundle(String, Locale, ClassLoader, Control) getBundle} for the
* complete description of the resource bundle loading process with a
* {@code ResourceBundle.Control}.
*
* @param baseName
* the base name of the resource bundle, a fully qualified
* class name
* @param targetLocale
* the locale for which a resource bundle is desired
* @param control
* the control which gives information for the resource
* bundle loading process
* @return a resource bundle for the given base name and a
* {@code Locale} in {@code locales}
* @throws NullPointerException
* if {@code baseName}, {@code locales} or
* {@code control} is {@code null}
* @throws MissingResourceException
* if no resource bundle for the specified base name in any
* of the {@code locales} can be found.
* @throws IllegalArgumentException
* if the given {@code control} doesn't perform properly
* (e.g., {@code control.getCandidateLocales} returns null.)
* Note that validation of {@code control} is performed as
* needed.
* @throws UnsupportedOperationException
* if this method is called in a named module
* @since 1.6
*/
@CallerSensitive
public static final ResourceBundle getBundle(String baseName, Locale targetLocale,
Control control) {
Class<?> caller = Reflection.getCallerClass();
checkNamedModule(caller);
return getBundleImpl(baseName, targetLocale, caller, control);
}
/**
* Gets a resource bundle using the specified base name, locale, and class
* loader.
*
* <p>When this method is called from a named module and the given
* loader is the class loader of the caller module, this is equivalent
* to calling:
* {@snippet lang=java :
* getBundle(baseName, targetLocale, callerModule);
* }
*
* otherwise, this is equivalent to calling:
* {@snippet lang=java :
* getBundle(baseName, targetLocale, loader, control);
* }
* where {@code control} is the default instance of {@link Control} unless
* a {@code Control} instance is provided by
* {@link ResourceBundleControlProvider} SPI. Refer to the
* description of <a href="#modify_default_behavior">modifying the default
* behavior</a>. The following describes the default behavior.
*
* <p>
* <b><a id="default_behavior">Resource Bundle Search and Loading Strategy</a></b>
*
* <p>{@code getBundle} uses the base name, the specified locale, and
* the default locale (obtained from {@link java.util.Locale#getDefault()
* Locale.getDefault}) to generate a sequence of <a
* id="candidates"><em>candidate bundle names</em></a>. If the specified
* locale's language, script, country, and variant are all empty strings,
* then the base name is the only candidate bundle name. Otherwise, a list
* of candidate locales is generated from the attribute values of the
* specified locale (language, script, country and variant) and appended to
* the base name. Typically, this will look like the following:
*
* <pre>
* baseName + "_" + language + "_" + script + "_" + country + "_" + variant
* baseName + "_" + language + "_" + script + "_" + country
* baseName + "_" + language + "_" + script
* baseName + "_" + language + "_" + country + "_" + variant
* baseName + "_" + language + "_" + country
* baseName + "_" + language
* </pre>
*
* <p>Candidate bundle names where the final component is an empty string
* are omitted, along with the underscore. For example, if country is an
* empty string, the second and the fifth candidate bundle names above
* would be omitted. Also, if script is an empty string, the candidate names
* including script are omitted. For example, a locale with language "de"
* and variant "JAVA" will produce candidate names with base name
* "MyResource" below.
*
* <pre>
* MyResource_de__JAVA
* MyResource_de
* </pre>
*
* In the case that the variant contains one or more underscores ('_'), a
* sequence of bundle names generated by truncating the last underscore and
* the part following it is inserted after a candidate bundle name with the
* original variant. For example, for a locale with language "en", script
* "Latn, country "US" and variant "WINDOWS_VISTA", and bundle base name
* "MyResource", the list of candidate bundle names below is generated:
*
* <pre>
* MyResource_en_Latn_US_WINDOWS_VISTA
* MyResource_en_Latn_US_WINDOWS
* MyResource_en_Latn_US
* MyResource_en_Latn
* MyResource_en_US_WINDOWS_VISTA
* MyResource_en_US_WINDOWS
* MyResource_en_US
* MyResource_en
* </pre>
*
* <blockquote><b>Note:</b> For some {@code Locale}s, the list of
* candidate bundle names contains extra names, or the order of bundle names
* is slightly modified. See the description of the default implementation
* of {@link Control#getCandidateLocales(String, Locale)
* getCandidateLocales} for details.</blockquote>
*
* <p>{@code getBundle} then iterates over the candidate bundle names
* to find the first one for which it can <em>instantiate</em> an actual
* resource bundle. It uses the default controls' {@link Control#getFormats
* getFormats} method, which generates two bundle names for each generated
* name, the first a class name and the second a properties file name. For
* each candidate bundle name, it attempts to create a resource bundle:
*
* <ul><li>First, it attempts to load a class using the generated class name.
* If such a class can be found and loaded using the specified class
* loader, is assignment compatible with ResourceBundle, is accessible from
* ResourceBundle, and can be instantiated, {@code getBundle} creates a
* new instance of this class and uses it as the <em>result resource
* bundle</em>.
*
* <li>Otherwise, {@code getBundle} attempts to locate a property
* resource file using the generated properties file name. It generates a
* path name from the candidate bundle name by replacing all "." characters
* with "/" and appending the string ".properties". It attempts to find a
* "resource" with this name using {@link
* java.lang.ClassLoader#getResource(java.lang.String)
* ClassLoader.getResource}. (Note that a "resource" in the sense of
* {@code getResource} has nothing to do with the contents of a
* resource bundle, it is just a container of data, such as a file.) If it
* finds a "resource", it attempts to create a new {@link
* PropertyResourceBundle} instance from its contents. If successful, this
* instance becomes the <em>result resource bundle</em>. </ul>
*
* <p>This continues until a result resource bundle is instantiated or the
* list of candidate bundle names is exhausted. If no matching resource
* bundle is found, the default control's {@link Control#getFallbackLocale
* getFallbackLocale} method is called, which returns the current default
* locale. A new sequence of candidate locale names is generated using this
* locale and searched again, as above.
*
* <p>If still no result bundle is found, the base name alone is looked up. If
* this still fails, a {@code MissingResourceException} is thrown.
*
* <p><a id="parent_chain"> Once a result resource bundle has been found,
* its <em>parent chain</em> is instantiated</a>. If the result bundle already
* has a parent (perhaps because it was returned from a cache) the chain is
* complete.
*
* <p>Otherwise, {@code getBundle} examines the remainder of the
* candidate locale list that was used during the pass that generated the
* result resource bundle. (As before, candidate bundle names where the
* final component is an empty string are omitted.) When it comes to the
* end of the candidate list, it tries the plain bundle name. With each of the
* candidate bundle names it attempts to instantiate a resource bundle (first
* looking for a class and then a properties file, as described above).
*
* <p>Whenever it succeeds, it calls the previously instantiated resource
* bundle's {@link #setParent(java.util.ResourceBundle) setParent} method
* with the new resource bundle. This continues until the list of names
* is exhausted or the current bundle already has a non-null parent.
*
* <p>Once the parent chain is complete, the bundle is returned.
*
* <p><b>Note:</b> {@code getBundle} caches instantiated resource
* bundles and might return the same resource bundle instance multiple times.
*
* <p><b>Note:</b>The {@code baseName} argument should be a fully
* qualified class name. However, for compatibility with earlier versions,
* Java SE Runtime Environments do not verify this, and so it is
* possible to access {@code PropertyResourceBundle}s by specifying a
* path name (using "/") instead of a fully qualified class name (using
* ".").
*
* <p><a id="default_behavior_example">
* <strong>Example:</strong></a>
* <p>
* The following class and property files are provided:
* <ul>
* <li>MyResources.class
* <li>MyResources.properties
* <li>MyResources_fr.properties
* <li>MyResources_fr_CH.class
* <li>MyResources_fr_CH.properties
* <li>MyResources_en.properties
* <li>MyResources_es_ES.class
* </ul>
*
* The contents of all files are valid (that is, public non-abstract
* subclasses of {@code ResourceBundle} for the ".class" files,
* syntactically correct ".properties" files). The default locale is
* {@code Locale("en", "GB")}.
*
* <p>Calling {@code getBundle} with the locale arguments below will
* instantiate resource bundles as follows:
*
* <table class="striped">
* <caption style="display:none">getBundle() locale to resource bundle mapping</caption>
* <thead>
* <tr><th scope="col">Locale</th><th scope="col">Resource bundle</th></tr>
* </thead>
* <tbody>
* <tr><th scope="row">Locale("fr", "CH")</th><td>MyResources_fr_CH.class, parent MyResources_fr.properties, parent MyResources.class</td></tr>
* <tr><th scope="row">Locale("fr", "FR")</th><td>MyResources_fr.properties, parent MyResources.class</td></tr>
* <tr><th scope="row">Locale("de", "DE")</th><td>MyResources_en.properties, parent MyResources.class</td></tr>
* <tr><th scope="row">Locale("en", "US")</th><td>MyResources_en.properties, parent MyResources.class</td></tr>
* <tr><th scope="row">Locale("es", "ES")</th><td>MyResources_es_ES.class, parent MyResources.class</td></tr>
* </tbody>
* </table>
*
* <p>The file MyResources_fr_CH.properties is never used because it is
* hidden by the MyResources_fr_CH.class. Likewise, MyResources.properties
* is also hidden by MyResources.class.
*
* @apiNote If the caller module is a named module and the given
* {@code loader} is the caller module's class loader, this method is
* equivalent to {@code getBundle(baseName, locale)}; otherwise, it may not
* find resource bundles from named modules.
* Use {@link #getBundle(String, Locale, Module)} to load resource bundles
* on behalf on a specific module instead.
*
* @param baseName the base name of the resource bundle, a fully qualified class name
* @param locale the locale for which a resource bundle is desired
* @param loader the class loader from which to load the resource bundle
* @return a resource bundle for the given base name and locale
* @throws java.lang.NullPointerException
* if {@code baseName}, {@code locale}, or {@code loader} is {@code null}
* @throws MissingResourceException
* if no resource bundle for the specified base name can be found
* @since 1.2
* @see <a href="#resource-bundle-modules">Resource Bundles and Named Modules</a>
*/
@CallerSensitive
public static ResourceBundle getBundle(String baseName, Locale locale,
ClassLoader loader)
{
if (loader == null) {
throw new NullPointerException();
}
Class<?> caller = Reflection.getCallerClass();
return getBundleImpl(baseName, locale, caller, loader, getDefaultControl(caller, baseName));
}
/**
* Returns a resource bundle using the specified base name, target
* locale, class loader and control. Unlike the {@link
* #getBundle(String, Locale, ClassLoader) getBundle}
* factory methods with no {@code control} argument, the given
* {@code control} specifies how to locate and instantiate resource
* bundles. Conceptually, the bundle loading process with the given
* {@code control} is performed in the following steps.
*
* <ol>
* <li>This factory method looks up the resource bundle in the cache for
* the specified {@code baseName}, {@code targetLocale} and
* {@code loader}. If the requested resource bundle instance is
* found in the cache and the time-to-live periods of the instance and
* all of its parent instances have not expired, the instance is returned
* to the caller. Otherwise, this factory method proceeds with the
* loading process below.</li>
*
* <li>The {@link ResourceBundle.Control#getFormats(String)
* control.getFormats} method is called to get resource bundle formats
* to produce bundle or resource names. The strings
* {@code "java.class"} and {@code "java.properties"}
* designate class-based and {@linkplain PropertyResourceBundle
* property}-based resource bundles, respectively. Other strings
* starting with {@code "java."} are reserved for future extensions
* and must not be used for application-defined formats. Other strings
* designate application-defined formats.</li>
*
* <li>The {@link ResourceBundle.Control#getCandidateLocales(String,
* Locale) control.getCandidateLocales} method is called with the target
* locale to get a list of <em>candidate {@code Locale}s</em> for
* which resource bundles are searched.</li>
*
* <li>The {@link ResourceBundle.Control#newBundle(String, Locale,
* String, ClassLoader, boolean) control.newBundle} method is called to
* instantiate a {@code ResourceBundle} for the base bundle name, a
* candidate locale, and a format. (Refer to the note on the cache
* lookup below.) This step is iterated over all combinations of the
* candidate locales and formats until the {@code newBundle} method
* returns a {@code ResourceBundle} instance or the iteration has
* used up all the combinations. For example, if the candidate locales
* are {@code Locale("de", "DE")}, {@code Locale("de")} and
* {@code Locale("")} and the formats are {@code "java.class"}
* and {@code "java.properties"}, then the following is the
* sequence of locale-format combinations to be used to call
* {@code control.newBundle}.
*
* <table class=striped style="width: 50%; text-align: left; margin-left: 40px;">
* <caption style="display:none">locale-format combinations for newBundle</caption>
* <thead>
* <tr>
* <th scope="col">Index</th>
* <th scope="col">{@code Locale}</th>
* <th scope="col">{@code format}</th>
* </tr>
* </thead>
* <tbody>
* <tr>
* <th scope="row">1</th>
* <td>{@code Locale("de", "DE")}</td>
* <td>{@code java.class}</td>
* </tr>
* <tr>
* <th scope="row">2</th>
* <td>{@code Locale("de", "DE")}</td>
* <td>{@code java.properties}</td>
* </tr>
* <tr>
* <th scope="row">3</th>
* <td>{@code Locale("de")}</td>
* <td>{@code java.class}</td>
* </tr>
* <tr>
* <th scope="row">4</th>
* <td>{@code Locale("de")}</td>
* <td>{@code java.properties}</td>
* </tr>
* <tr>
* <th scope="row">5</th>
* <td>{@code Locale("")}</td>
* <td>{@code java.class}</td>
* </tr>
* <tr>
* <th scope="row">6</th>
* <td>{@code Locale("")}</td>
* <td>{@code java.properties}</td>
* </tr>
* </tbody>
* </table>
* </li>
*
* <li>If the previous step has found no resource bundle, proceed to
* Step 6. If a bundle has been found that is a base bundle (a bundle
* for {@code Locale("")}), and the candidate locale list only contained
* {@code Locale("")}, return the bundle to the caller. If a bundle
* has been found that is a base bundle, but the candidate locale list
* contained locales other than Locale(""), put the bundle on hold and
* proceed to Step 6. If a bundle has been found that is not a base
* bundle, proceed to Step 7.</li>
*
* <li>The {@link ResourceBundle.Control#getFallbackLocale(String,
* Locale) control.getFallbackLocale} method is called to get a fallback
* locale (alternative to the current target locale) to try further
* finding a resource bundle. If the method returns a non-null locale,
* it becomes the next target locale and the loading process starts over
* from Step 3. Otherwise, if a base bundle was found and put on hold in
* a previous Step 5, it is returned to the caller now. Otherwise, a
* MissingResourceException is thrown.</li>
*
* <li>At this point, we have found a resource bundle that's not the
* base bundle. If this bundle set its parent during its instantiation,
* it is returned to the caller. Otherwise, its <a
* href="./ResourceBundle.html#parent_chain">parent chain</a> is
* instantiated based on the list of candidate locales from which it was
* found. Finally, the bundle is returned to the caller.</li>
* </ol>
*
* <p>During the resource bundle loading process above, this factory
* method looks up the cache before calling the {@link
* Control#newBundle(String, Locale, String, ClassLoader, boolean)
* control.newBundle} method. If the time-to-live period of the
* resource bundle found in the cache has expired, the factory method
* calls the {@link ResourceBundle.Control#needsReload(String, Locale,
* String, ClassLoader, ResourceBundle, long) control.needsReload}
* method to determine whether the resource bundle needs to be reloaded.
* If reloading is required, the factory method calls
* {@code control.newBundle} to reload the resource bundle. If
* {@code control.newBundle} returns {@code null}, the factory
* method puts a dummy resource bundle in the cache as a mark of
* nonexistent resource bundles in order to avoid lookup overhead for
* subsequent requests. Such dummy resource bundles are under the same
* expiration control as specified by {@code control}.
*
* <p>All resource bundles loaded are cached by default. Refer to
* {@link Control#getTimeToLive(String,Locale)
* control.getTimeToLive} for details.
*
* <p>The following is an example of the bundle loading process with the
* default {@code ResourceBundle.Control} implementation.
*
* <p>Conditions:
* <ul>
* <li>Base bundle name: {@code foo.bar.Messages}
* <li>Requested {@code Locale}: {@link Locale#ITALY}</li>
* <li>Default {@code Locale}: {@link Locale#FRENCH}</li>
* <li>Available resource bundles:
* {@code foo/bar/Messages_fr.properties} and
* {@code foo/bar/Messages.properties}</li>
* </ul>
*
* <p>First, {@code getBundle} tries loading a resource bundle in
* the following sequence.
*
* <ul>
* <li>class {@code foo.bar.Messages_it_IT}
* <li>file {@code foo/bar/Messages_it_IT.properties}
* <li>class {@code foo.bar.Messages_it}</li>
* <li>file {@code foo/bar/Messages_it.properties}</li>
* <li>class {@code foo.bar.Messages}</li>
* <li>file {@code foo/bar/Messages.properties}</li>
* </ul>
*
* <p>At this point, {@code getBundle} finds
* {@code foo/bar/Messages.properties}, which is put on hold
* because it's the base bundle. {@code getBundle} calls {@link
* Control#getFallbackLocale(String, Locale)
* control.getFallbackLocale("foo.bar.Messages", Locale.ITALY)} which
* returns {@code Locale.FRENCH}. Next, {@code getBundle}
* tries loading a bundle in the following sequence.
*
* <ul>
* <li>class {@code foo.bar.Messages_fr}</li>
* <li>file {@code foo/bar/Messages_fr.properties}</li>
* <li>class {@code foo.bar.Messages}</li>
* <li>file {@code foo/bar/Messages.properties}</li>
* </ul>
*
* <p>{@code getBundle} finds
* {@code foo/bar/Messages_fr.properties} and creates a
* {@code ResourceBundle} instance. Then, {@code getBundle}
* sets up its parent chain from the list of the candidate locales. Only
* {@code foo/bar/Messages.properties} is found in the list and
* {@code getBundle} creates a {@code ResourceBundle} instance
* that becomes the parent of the instance for
* {@code foo/bar/Messages_fr.properties}.
*
* @param baseName
* the base name of the resource bundle, a fully qualified
* class name
* @param targetLocale
* the locale for which a resource bundle is desired
* @param loader
* the class loader from which to load the resource bundle
* @param control
* the control which gives information for the resource
* bundle loading process
* @return a resource bundle for the given base name and locale
* @throws NullPointerException
* if {@code baseName}, {@code targetLocale},
* {@code loader}, or {@code control} is
* {@code null}
* @throws MissingResourceException
* if no resource bundle for the specified base name can be found
* @throws IllegalArgumentException
* if the given {@code control} doesn't perform properly
* (e.g., {@code control.getCandidateLocales} returns null.)
* Note that validation of {@code control} is performed as
* needed.
* @throws UnsupportedOperationException
* if this method is called in a named module
* @since 1.6
*/
@CallerSensitive
public static ResourceBundle getBundle(String baseName, Locale targetLocale,
ClassLoader loader, Control control) {
if (loader == null || control == null) {
throw new NullPointerException();
}
Class<?> caller = Reflection.getCallerClass();
checkNamedModule(caller);
return getBundleImpl(baseName, targetLocale, caller, loader, control);
}
private static Control getDefaultControl(Class<?> caller, String baseName) {
Module callerModule = getCallerModule(caller);
return getDefaultControl(callerModule, baseName);
}
private static Control getDefaultControl(Module targetModule, String baseName) {
return targetModule.isNamed() ?
Control.INSTANCE :
ResourceBundleControlProviderHolder.getControl(baseName);
}
private static class ResourceBundleControlProviderHolder {
private static final List<ResourceBundleControlProvider> CONTROL_PROVIDERS =
ServiceLoader.load(ResourceBundleControlProvider.class,
ClassLoader.getSystemClassLoader()).stream()
.map(ServiceLoader.Provider::get)
.toList();
private static Control getControl(String baseName) {
return CONTROL_PROVIDERS.isEmpty() ?
Control.INSTANCE :
CONTROL_PROVIDERS.stream()
.flatMap(provider -> Stream.ofNullable(provider.getControl(baseName)))
.findFirst()
.orElse(Control.INSTANCE);
}
}
private static void checkNamedModule(Class<?> caller) {
Module callerModule = getCallerModule(caller);
if (callerModule.isNamed()) {
throw new UnsupportedOperationException(
"ResourceBundle.Control not supported in named modules");
}
}
private static ResourceBundle getBundleImpl(String baseName,
Locale locale,
Class<?> caller,
Control control) {
ClassLoader loader = getLoader(getCallerModule(caller));
return getBundleImpl(baseName, locale, caller, loader, control);
}
/*
* Determine the module to be used for the caller. If
* Reflection::getCallerClass is called from JNI with an empty
* stack frame the caller will be null, so the system class loader unnamed
* module will be used.
*/
private static Module getCallerModule(Class<?> caller) {
return (caller != null) ? caller.getModule()
: ClassLoader.getSystemClassLoader().getUnnamedModule();
}
/**
* This method will find resource bundles using the legacy mechanism
* if the caller is unnamed module or the given class loader is
* not the class loader of the caller module getting the resource
* bundle, i.e. find the class that is visible to the class loader
* and properties from unnamed module.
*
* The module-aware resource bundle lookup mechanism will load
* the service providers using the service loader mechanism
* as well as properties local in the caller module.
*/
private static ResourceBundle getBundleImpl(String baseName,
Locale locale,
Class<?> caller,
ClassLoader loader,
Control control) {
Module callerModule = getCallerModule(caller);
// get resource bundles for a named module only if loader is the module's class loader
if (callerModule.isNamed() && loader == getLoader(callerModule)) {
return getBundleImpl(callerModule, callerModule, baseName, locale, control);
}
// find resource bundles from unnamed module of given class loader
// Java agent can add to the bootclasspath e.g. via
// java.lang.instrument.Instrumentation and load classes in unnamed module.
// It may call RB::getBundle that will end up here with loader == null.
Module unnamedModule = loader != null
? loader.getUnnamedModule()
: BootLoader.getUnnamedModule();
return getBundleImpl(callerModule, unnamedModule, baseName, locale, control);
}
private static ResourceBundle getBundleFromModule(Class<?> caller,
Module module,
String baseName,
Locale locale,
Control control) {
Objects.requireNonNull(module);
Module callerModule = getCallerModule(caller);
return getBundleImpl(callerModule, module, baseName, locale, control);
}
private static ResourceBundle getBundleImpl(Module callerModule,
Module module,
String baseName,
Locale locale,
Control control) {
if (locale == null || control == null) {
throw new NullPointerException();
}
// We create a CacheKey here for use by this call. The base name
// and modules will never change during the bundle loading
// process. We have to make sure that the locale is set before
// using it as a cache key.
CacheKey cacheKey = new CacheKey(baseName, locale, module, callerModule);
ResourceBundle bundle = null;
// Quick lookup of the cache.
BundleReference bundleRef = cacheList.get(cacheKey);
if (bundleRef != null) {
bundle = bundleRef.get();
bundleRef = null;
}
// If this bundle and all of its parents are valid (not expired),
// then return this bundle. If any of the bundles is expired, we
// don't call control.needsReload here but instead drop into the
// complete loading process below.
if (isValidBundle(bundle) && hasValidParentChain(bundle)) {
return bundle;
}
// No valid bundle was found in the cache, so we need to load the
// resource bundle and its parents.
boolean isKnownControl = (control == Control.INSTANCE) ||
(control instanceof SingleFormatControl);
List<String> formats = control.getFormats(baseName);
if (!isKnownControl && !checkList(formats)) {
throw new IllegalArgumentException("Invalid Control: getFormats");
}
ResourceBundle baseBundle = null;
for (Locale targetLocale = locale;
targetLocale != null;
targetLocale = control.getFallbackLocale(baseName, targetLocale)) {
List<Locale> candidateLocales = control.getCandidateLocales(baseName, targetLocale);
if (!isKnownControl && !checkList(candidateLocales)) {
throw new IllegalArgumentException("Invalid Control: getCandidateLocales");
}
bundle = findBundle(callerModule, module, cacheKey,
candidateLocales, formats, 0, control, baseBundle);
// If the loaded bundle is the base bundle and exactly for the
// requested locale or the only candidate locale, then take the
// bundle as the resulting one. If the loaded bundle is the base
// bundle, it's put on hold until we finish processing all
// fallback locales.
if (isValidBundle(bundle)) {
boolean isBaseBundle = Locale.ROOT.equals(bundle.locale);
if (!isBaseBundle || bundle.locale.equals(locale)
|| (candidateLocales.size() == 1
&& bundle.locale.equals(candidateLocales.get(0)))) {
break;
}
// If the base bundle has been loaded, keep the reference in
// baseBundle so that we can avoid any redundant loading in case
// the control specify not to cache bundles.
if (isBaseBundle && baseBundle == null) {
baseBundle = bundle;
}
}
}
if (bundle == null) {
if (baseBundle == null) {
throwMissingResourceException(baseName, locale, cacheKey.getCause());
}
bundle = baseBundle;
}
// keep callerModule and module reachable for as long as we are operating
// with WeakReference(s) to them (in CacheKey)...
Reference.reachabilityFence(callerModule);
Reference.reachabilityFence(module);
return bundle;
}
/**
* Checks if the given {@code List} is not null, not empty,
* not having null in its elements.
*/
private static boolean checkList(List<?> a) {
boolean valid = (a != null && !a.isEmpty());
if (valid) {
int size = a.size();
for (int i = 0; valid && i < size; i++) {
valid = (a.get(i) != null);
}
}
return valid;
}
private static ResourceBundle findBundle(Module callerModule,
Module module,
CacheKey cacheKey,
List<Locale> candidateLocales,
List<String> formats,
int index,
Control control,
ResourceBundle baseBundle) {
Locale targetLocale = candidateLocales.get(index);
ResourceBundle parent = null;
if (index != candidateLocales.size() - 1) {
parent = findBundle(callerModule, module, cacheKey,
candidateLocales, formats, index + 1,
control, baseBundle);
} else if (baseBundle != null && Locale.ROOT.equals(targetLocale)) {
return baseBundle;
}
// Before we do the real loading work, see whether we need to
// do some housekeeping: If references to modules or
// resource bundles have been nulled out, remove all related
// information from the cache.
Object ref;
while ((ref = referenceQueue.poll()) != null) {
cacheList.remove(((CacheKeyReference)ref).getCacheKey());
}
// flag indicating the resource bundle has expired in the cache
boolean expiredBundle = false;
// First, look up the cache to see if it's in the cache, without
// attempting to load bundle.
cacheKey.setLocale(targetLocale);
ResourceBundle bundle = findBundleInCache(cacheKey, control);
if (isValidBundle(bundle)) {
expiredBundle = bundle.expired;
if (!expiredBundle) {
// If its parent is the one asked for by the candidate
// locales (the runtime lookup path), we can take the cached
// one. (If it's not identical, then we'd have to check the
// parent's parents to be consistent with what's been
// requested.)
if (bundle.parent == parent) {
return bundle;
}
// Otherwise, remove the cached one since we can't keep
// the same bundles having different parents.
BundleReference bundleRef = cacheList.get(cacheKey);
if (bundleRef != null && bundleRef.refersTo(bundle)) {
cacheList.remove(cacheKey, bundleRef);
}
}
}
if (bundle != NONEXISTENT_BUNDLE) {
trace("findBundle: %d %s %s formats: %s%n", index, candidateLocales, cacheKey, formats);
if (module.isNamed()) {
bundle = loadBundle(cacheKey, formats, control, module, callerModule);
} else {
bundle = loadBundle(cacheKey, formats, control, expiredBundle);
}
if (bundle != null) {
if (bundle.parent == null) {
bundle.setParent(parent);
}
bundle.locale = targetLocale;
bundle = putBundleInCache(cacheKey, bundle, control);
return bundle;
}
// Put NONEXISTENT_BUNDLE in the cache as a mark that there's no bundle
// instance for the locale.
putBundleInCache(cacheKey, NONEXISTENT_BUNDLE, control);
}
return parent;
}
private static final String UNKNOWN_FORMAT = "";
/*
* Loads a ResourceBundle in named modules
*/
private static ResourceBundle loadBundle(CacheKey cacheKey,
List<String> formats,
Control control,
Module module,
Module callerModule) {
String baseName = cacheKey.getName();
Locale targetLocale = cacheKey.getLocale();
ResourceBundle bundle = null;
if (cacheKey.hasProviders()) {
if (callerModule == module) {
bundle = loadBundleFromProviders(baseName,
targetLocale,
cacheKey.getProviders(),
cacheKey);
} else {
// load from provider if the caller module has access to the
// service type and also declares `uses`
ClassLoader loader = getLoader(module);
Class<ResourceBundleProvider> svc =
getResourceBundleProviderType(baseName, loader);
if (svc != null
&& Reflection.verifyModuleAccess(callerModule, svc)
&& callerModule.canUse(svc)) {
bundle = loadBundleFromProviders(baseName,
targetLocale,
cacheKey.getProviders(),
cacheKey);
}
}
if (bundle != null) {
cacheKey.setFormat(UNKNOWN_FORMAT);
}
}
// If none of providers returned a bundle and the caller has no provider,
// look up module-local bundles or from the class path
if (bundle == null && !cacheKey.callerHasProvider()) {
for (String format : formats) {
try {
bundle = switch (format) {
case "java.class" -> ResourceBundleProviderHelper
.loadResourceBundle(callerModule, module, baseName, targetLocale);
case "java.properties" -> ResourceBundleProviderHelper
.loadPropertyResourceBundle(callerModule, module, baseName, targetLocale);
default -> throw new InternalError("unexpected format: " + format);
};
if (bundle != null) {
cacheKey.setFormat(format);
break;
}
} catch (LinkageError|Exception e) {
cacheKey.setCause(e);
}
}
}
return bundle;
}
/**
* Returns a ServiceLoader that will find providers that are bound to
* a given named module.
*/
private static ServiceLoader<ResourceBundleProvider> getServiceLoader(Module module,
String baseName)
{
if (!module.isNamed()) {
return null;
}
ClassLoader loader = getLoader(module);
Class<ResourceBundleProvider> service =
getResourceBundleProviderType(baseName, loader);
if (service != null && Reflection.verifyModuleAccess(module, service)) {
try {
// locate providers that are visible to the class loader
// ServiceConfigurationError will be thrown if the module
// does not declare `uses` the service type
return ServiceLoader.load(service, loader, module);
} catch (ServiceConfigurationError e) {
// "uses" not declared
return null;
}
}
return null;
}
/**
* Returns the service type of the given baseName that is visible
* to the given class loader
*/
private static Class<ResourceBundleProvider>
getResourceBundleProviderType(String baseName, ClassLoader loader)
{
// Look up <packagename> + ".spi." + <name>"Provider"
int i = baseName.lastIndexOf('.');
if (i <= 0) {
return null;
}
String name = baseName.substring(i+1, baseName.length()) + "Provider";
String providerName = baseName.substring(0, i) + ".spi." + name;
// Use the class loader of the getBundle caller so that the caller's
// visibility of the provider type is checked.
try {
Class<?> c = Class.forName(providerName, false, loader);
if (ResourceBundleProvider.class.isAssignableFrom(c)) {
@SuppressWarnings("unchecked")
Class<ResourceBundleProvider> s = (Class<ResourceBundleProvider>) c;
return s;
}
} catch (ClassNotFoundException _) {}
return null;
}
/**
* Loads ResourceBundle from service providers.
*/
private static ResourceBundle loadBundleFromProviders(String baseName,
Locale locale,
ServiceLoader<ResourceBundleProvider> providers,
CacheKey cacheKey)
{
if (providers == null) return null;
for (Iterator<ResourceBundleProvider> itr = providers.iterator(); itr.hasNext(); ) {
try {
ResourceBundleProvider provider = itr.next();
if (cacheKey != null && cacheKey.callerHasProvider == null
&& cacheKey.getModule() == provider.getClass().getModule()) {
cacheKey.callerHasProvider = Boolean.TRUE;
}
ResourceBundle bundle = provider.getBundle(baseName, locale);
trace("provider %s %s locale: %s bundle: %s%n", provider, baseName, locale, bundle);
if (bundle != null) {
return bundle;
}
} catch (ServiceConfigurationError e) {
if (cacheKey != null) {
cacheKey.setCause(e);
}
}
}
if (cacheKey != null && cacheKey.callerHasProvider == null) {
cacheKey.callerHasProvider = Boolean.FALSE;
}
return null;
}
/*
* Legacy mechanism to load resource bundles
*/
private static ResourceBundle loadBundle(CacheKey cacheKey,
List<String> formats,
Control control,
boolean reload) {
// Here we actually load the bundle in the order of formats
// specified by the getFormats() value.
Locale targetLocale = cacheKey.getLocale();
Module module = cacheKey.getModule();
if (module == null) {
// should not happen
throw new InternalError(
"Module for cache key: " + cacheKey + " has been GCed.");
}
ClassLoader loader = getLoaderForControl(module);
ResourceBundle bundle = null;
for (String format : formats) {
try {
// ResourceBundle.Control.newBundle may be overridden
bundle = control.newBundle(cacheKey.getName(), targetLocale, format,
loader, reload);
} catch (LinkageError | Exception error) {
// We need to handle the LinkageError case due to
// inconsistent case-sensitivity in ClassLoader.
// See 6572242 for details.
cacheKey.setCause(error);
}
if (bundle != null) {
// Set the format in the cache key so that it can be
// used when calling needsReload later.
cacheKey.setFormat(format);
bundle.name = cacheKey.getName();
bundle.locale = targetLocale;
// Bundle provider might reuse instances. So we should make
// sure to clear the expired flag here.
bundle.expired = false;
break;
}
}
return bundle;
}
private static boolean isValidBundle(ResourceBundle bundle) {
return bundle != null && bundle != NONEXISTENT_BUNDLE;
}
/**
* Determines whether any of resource bundles in the parent chain,
* including the leaf, have expired.
*/
private static boolean hasValidParentChain(ResourceBundle bundle) {
long now = System.currentTimeMillis();
while (bundle != null) {
if (bundle.expired) {
return false;
}
CacheKey key = bundle.cacheKey;
if (key != null) {
long expirationTime = key.expirationTime;
if (expirationTime >= 0 && expirationTime <= now) {
return false;
}
}
bundle = bundle.parent;
}
return true;
}
/**
* Throw a MissingResourceException with proper message
*/
private static void throwMissingResourceException(String baseName,
Locale locale,
Throwable cause) {
// If the cause is a MissingResourceException, avoid creating
// a long chain. (6355009)
if (cause instanceof MissingResourceException) {
cause = null;
}
throw new MissingResourceException("Can't find bundle for base name "
+ baseName + ", locale " + locale,
baseName + "_" + locale, // className
"", // key
cause);
}
/**
* Finds a bundle in the cache. Any expired bundles are marked as
* `expired' and removed from the cache upon return.
*
* @param cacheKey the key to look up the cache
* @param control the Control to be used for the expiration control
* @return the cached bundle, or null if the bundle is not found in the
* cache or its parent has expired. {@code bundle.expire} is true
* upon return if the bundle in the cache has expired.
*/
private static ResourceBundle findBundleInCache(CacheKey cacheKey,
Control control) {
BundleReference bundleRef = cacheList.get(cacheKey);
if (bundleRef == null) {
return null;
}
ResourceBundle bundle = bundleRef.get();
if (bundle == null) {
return null;
}
ResourceBundle p = bundle.parent;
assert p != NONEXISTENT_BUNDLE;
// If the parent has expired, then this one must also expire. We
// check only the immediate parent because the actual loading is
// done from the root (base) to leaf (child) and the purpose of
// checking is to propagate expiration towards the leaf. For
// example, if the requested locale is ja_JP_JP and there are
// bundles for all of the candidates in the cache, we have a list,
//
// base <- ja <- ja_JP <- ja_JP_JP
//
// If ja has expired, then it will reload ja and the list becomes a
// tree.
//
// base <- ja (new)
// " <- ja (expired) <- ja_JP <- ja_JP_JP
//
// When looking up ja_JP in the cache, it finds ja_JP in the cache
// which references to the expired ja. Then, ja_JP is marked as
// expired and removed from the cache. This will be propagated to
// ja_JP_JP.
//
// Now, it's possible, for example, that while loading new ja_JP,
// someone else has started loading the same bundle and finds the
// base bundle has expired. Then, what we get from the first
// getBundle call includes the expired base bundle. However, if
// someone else didn't start its loading, we wouldn't know if the
// base bundle has expired at the end of the loading process. The
// expiration control doesn't guarantee that the returned bundle and
// its parents haven't expired.
//
// We could check the entire parent chain to see if there's any in
// the chain that has expired. But this process may never end. An
// extreme case would be that getTimeToLive returns 0 and
// needsReload always returns true.
if (p != null && p.expired) {
assert bundle != NONEXISTENT_BUNDLE;
bundle.expired = true;
bundle.cacheKey = null;
cacheList.remove(cacheKey, bundleRef);
bundle = null;
} else {
CacheKey key = bundleRef.getCacheKey();
long expirationTime = key.expirationTime;
if (!bundle.expired && expirationTime >= 0 &&
expirationTime <= System.currentTimeMillis()) {
// its TTL period has expired.
if (bundle != NONEXISTENT_BUNDLE) {
// Synchronize here to call needsReload to avoid
// redundant concurrent calls for the same bundle.
synchronized (bundle) {
expirationTime = key.expirationTime;
if (!bundle.expired && expirationTime >= 0 &&
expirationTime <= System.currentTimeMillis()) {
try {
Module module = cacheKey.getModule();
bundle.expired =
module == null || // already GCed
control.needsReload(key.getName(),
key.getLocale(),
key.getFormat(),
getLoaderForControl(module),
bundle,
key.loadTime);
} catch (Exception e) {
cacheKey.setCause(e);
}
if (bundle.expired) {
// If the bundle needs to be reloaded, then
// remove the bundle from the cache, but
// return the bundle with the expired flag
// on.
bundle.cacheKey = null;
cacheList.remove(cacheKey, bundleRef);
} else {
// Update the expiration control info. and reuse
// the same bundle instance
setExpirationTime(key, control);
}
}
}
} else {
// We just remove NONEXISTENT_BUNDLE from the cache.
cacheList.remove(cacheKey, bundleRef);
bundle = null;
}
}
}
return bundle;
}
/**
* Put a new bundle in the cache.
*
* @param cacheKey the key for the resource bundle
* @param bundle the resource bundle to be put in the cache
* @return the ResourceBundle for the cacheKey; if someone has put
* the bundle before this call, the one found in the cache is
* returned.
*/
private static ResourceBundle putBundleInCache(CacheKey cacheKey,
ResourceBundle bundle,
Control control) {
setExpirationTime(cacheKey, control);
if (cacheKey.expirationTime != Control.TTL_DONT_CACHE) {
CacheKey key = new CacheKey(cacheKey);
BundleReference bundleRef = new BundleReference(bundle, referenceQueue, key);
bundle.cacheKey = key;
// Put the bundle in the cache if it's not been in the cache.
BundleReference result = cacheList.putIfAbsent(key, bundleRef);
// If someone else has put the same bundle in the cache before
// us and it has not expired, we should use the one in the cache.
if (result != null) {
ResourceBundle rb = result.get();
if (rb != null && !rb.expired) {
// Clear the back link to the cache key
bundle.cacheKey = null;
bundle = rb;
// Clear the reference in the BundleReference so that
// it won't be enqueued.
bundleRef.clear();
} else {
// Replace the invalid (garbage collected or expired)
// instance with the valid one.
cacheList.put(key, bundleRef);
}
}
}
return bundle;
}
private static void setExpirationTime(CacheKey cacheKey, Control control) {
long ttl = control.getTimeToLive(cacheKey.getName(),
cacheKey.getLocale());
if (ttl >= 0) {
// If any expiration time is specified, set the time to be
// expired in the cache.
long now = System.currentTimeMillis();
cacheKey.loadTime = now;
cacheKey.expirationTime = now + ttl;
} else if (ttl >= Control.TTL_NO_EXPIRATION_CONTROL) {
cacheKey.expirationTime = ttl;
} else {
throw new IllegalArgumentException("Invalid Control: TTL=" + ttl);
}
}
/**
* Removes all resource bundles from the cache that have been loaded
* by the caller's module.
*
* @since 1.6
* @see ResourceBundle.Control#getTimeToLive(String,Locale)
*/
@CallerSensitive
public static final void clearCache() {
Module callerModule = getCallerModule(Reflection.getCallerClass());
cacheList.keySet().removeIf(
key -> key.getCallerModule() == callerModule
);
}
/**
* Removes all resource bundles from the cache that have been loaded
* by the given class loader.
*
* @param loader the class loader
* @throws NullPointerException if {@code loader} is null
* @since 1.6
* @see ResourceBundle.Control#getTimeToLive(String,Locale)
*/
public static final void clearCache(ClassLoader loader) {
Objects.requireNonNull(loader);
cacheList.keySet().removeIf(
key -> {
Module m;
return (m = key.getModule()) != null &&
getLoader(m) == loader;
}
);
}
/**
* Gets an object for the given key from this resource bundle.
* Returns null if this resource bundle does not contain an
* object for the given key.
*
* @param key the key for the desired object
* @throws NullPointerException if {@code key} is {@code null}
* @return the object for the given key, or null
*/
protected abstract Object handleGetObject(String key);
/**
* Returns an enumeration of the keys.
*
* @return an {@code Enumeration} of the keys contained in
* this {@code ResourceBundle} and its parent bundles.
*/
public abstract Enumeration<String> getKeys();
/**
* Determines whether the given {@code key} is contained in
* this {@code ResourceBundle} or its parent bundles.
*
* @param key
* the resource {@code key}
* @return {@code true} if the given {@code key} is
* contained in this {@code ResourceBundle} or its
* parent bundles; {@code false} otherwise.
* @throws NullPointerException
* if {@code key} is {@code null}
* @since 1.6
*/
public boolean containsKey(String key) {
if (key == null) {
throw new NullPointerException();
}
for (ResourceBundle rb = this; rb != null; rb = rb.parent) {
if (rb.handleKeySet().contains(key)) {
return true;
}
}
return false;
}
/**
* Returns a {@code Set} of all keys contained in this
* {@code ResourceBundle} and its parent bundles.
*
* @return a {@code Set} of all keys contained in this
* {@code ResourceBundle} and its parent bundles.
* @since 1.6
*/
public Set<String> keySet() {
Set<String> keys = new HashSet<>();
for (ResourceBundle rb = this; rb != null; rb = rb.parent) {
keys.addAll(rb.handleKeySet());
}
return keys;
}
/**
* Returns a {@code Set} of the keys contained <em>only</em>
* in this {@code ResourceBundle}.
*
* <p>The default implementation returns a {@code Set} of the
* keys returned by the {@link #getKeys() getKeys} method except
* for the ones for which the {@link #handleGetObject(String)
* handleGetObject} method returns {@code null}. Once the
* {@code Set} has been created, the value is kept in this
* {@code ResourceBundle} in order to avoid producing the
* same {@code Set} in subsequent calls. Subclasses can
* override this method for faster handling.
*
* @return a {@code Set} of the keys contained only in this
* {@code ResourceBundle}
* @since 1.6
*/
protected Set<String> handleKeySet() {
if (keySet == null) {
synchronized (this) {
if (keySet == null) {
Set<String> keys = new HashSet<>();
Enumeration<String> enumKeys = getKeys();
while (enumKeys.hasMoreElements()) {
String key = enumKeys.nextElement();
if (handleGetObject(key) != null) {
keys.add(key);
}
}
keySet = keys;
}
}
}
return keySet;
}
/**
* {@code ResourceBundle.Control} defines a set of callback methods
* that are invoked by the {@link ResourceBundle#getBundle(String,
* Locale, ClassLoader, Control) ResourceBundle.getBundle} factory
* methods during the bundle loading process. In other words, a
* {@code ResourceBundle.Control} collaborates with the factory
* methods for loading resource bundles. The default implementation of
* the callback methods provides the information necessary for the
* factory methods to perform the <a
* href="./ResourceBundle.html#default_behavior">default behavior</a>.
*
* <p> {@link ResourceBundle.Control} is designed for an application deployed
* in an unnamed module, for example to support resource bundles in
* non-standard formats or package localized resources in a non-traditional
* convention. {@link ResourceBundleProvider} is the replacement for
* {@code ResourceBundle.Control} when migrating to modules.
* {@code UnsupportedOperationException} will be thrown when a factory
* method that takes the {@code ResourceBundle.Control} parameter is called.
*
* <p>In addition to the callback methods, the {@link
* #toBundleName(String, Locale) toBundleName} and {@link
* #toResourceName(String, String) toResourceName} methods are defined
* primarily for convenience in implementing the callback
* methods. However, the {@code toBundleName} method could be
* overridden to provide different conventions in the organization and
* packaging of localized resources. The {@code toResourceName}
* method is {@code final} to avoid use of wrong resource and class
* name separators.
*
* <p>Two factory methods, {@link #getControl(List)} and {@link
* #getNoFallbackControl(List)}, provide
* {@code ResourceBundle.Control} instances that implement common
* variations of the default bundle loading process.
*
* <p>The formats returned by the {@link Control#getFormats(String)
* getFormats} method and candidate locales returned by the {@link
* ResourceBundle.Control#getCandidateLocales(String, Locale)
* getCandidateLocales} method must be consistent in all
* {@code ResourceBundle.getBundle} invocations for the same base
* bundle. Otherwise, the {@code ResourceBundle.getBundle} methods
* may return unintended bundles. For example, if only
* {@code "java.class"} is returned by the {@code getFormats}
* method for the first call to {@code ResourceBundle.getBundle}
* and only {@code "java.properties"} for the second call, then the
* second call will return the class-based one that has been cached
* during the first call.
*
* <p>A {@code ResourceBundle.Control} instance must be thread-safe
* if it's simultaneously used by multiple threads.
* {@code ResourceBundle.getBundle} does not synchronize to call
* the {@code ResourceBundle.Control} methods. The default
* implementations of the methods are thread-safe.
*
* <p>Applications can specify {@code ResourceBundle.Control}
* instances returned by the {@code getControl} factory methods or
* created from a subclass of {@code ResourceBundle.Control} to
* customize the bundle loading process. The following are examples of
* changing the default bundle loading process.
*
* <p><b>Example 1</b>
*
* <p>The following code lets {@code ResourceBundle.getBundle} look
* up only properties-based resources.
*
* {@snippet lang=java :
* import java.util.*;
* import static java.util.ResourceBundle.Control.*;
* ...
* ResourceBundle bundle =
* ResourceBundle.getBundle("MyResources", Locale.forLanguageTag("fr-CH"),
* ResourceBundle.Control.getControl(FORMAT_PROPERTIES));
* }
*
* Given the resource bundles in the <a
* href="./ResourceBundle.html#default_behavior_example">example</a> in
* the {@code ResourceBundle.getBundle} description, this
* {@code ResourceBundle.getBundle} call loads
* {@code MyResources_fr_CH.properties} whose parent is
* {@code MyResources_fr.properties} whose parent is
* {@code MyResources.properties}. ({@code MyResources_fr_CH.properties}
* is not hidden, but {@code MyResources_fr_CH.class} is.)
*
* <p><b>Example 2</b>
*
* <p>The following is an example of loading XML-based bundles
* using {@link Properties#loadFromXML(java.io.InputStream)
* Properties.loadFromXML}.
*
* {@snippet lang=java :
* ResourceBundle rb = ResourceBundle.getBundle("Messages",
* new ResourceBundle.Control() {
* public List<String> getFormats(String baseName) {
* if (baseName == null)
* throw new NullPointerException();
* return Arrays.asList("xml");
* }
* public ResourceBundle newBundle(String baseName,
* Locale locale,
* String format,
* ClassLoader loader,
* boolean reload)
* throws IllegalAccessException,
* InstantiationException,
* IOException {
* if (baseName == null || locale == null
* || format == null || loader == null)
* throw new NullPointerException();
* ResourceBundle bundle = null;
* if (format.equals("xml")) {
* String bundleName = toBundleName(baseName, locale);
* String resourceName = toResourceName(bundleName, format);
* InputStream stream = null;
* if (reload) {
* URL url = loader.getResource(resourceName);
* if (url != null) {
* URLConnection connection = url.openConnection();
* if (connection != null) {
* // Disable caches to get fresh data for
* // reloading.
* connection.setUseCaches(false);
* stream = connection.getInputStream();
* }
* }
* } else {
* stream = loader.getResourceAsStream(resourceName);
* }
* if (stream != null) {
* BufferedInputStream bis = new BufferedInputStream(stream);
* bundle = new XMLResourceBundle(bis);
* bis.close();
* }
* }
* return bundle;
* }
* });
*
* ...
*
* private static class XMLResourceBundle extends ResourceBundle {
* private Properties props;
* XMLResourceBundle(InputStream stream) throws IOException {
* props = new Properties();
* props.loadFromXML(stream);
* }
* protected Object handleGetObject(String key) {
* return props.getProperty(key);
* }
* public Enumeration<String> getKeys() {
* ...
* }
* }
* }
*
* @apiNote {@code ResourceBundle.Control} is not supported
* in named modules. If the {@code ResourceBundle.getBundle} method with
* a {@code ResourceBundle.Control} is called in a named module, the method
* will throw an {@link UnsupportedOperationException}. Any service providers
* of {@link ResourceBundleControlProvider} are ignored in named modules.
*
* @since 1.6
* @see java.util.spi.ResourceBundleProvider
*/
public static class Control {
/**
* The default format {@code List}, which contains the strings
* {@code "java.class"} and {@code "java.properties"}, in
* this order. This {@code List} is unmodifiable.
*
* @see #getFormats(String)
*/
public static final List<String> FORMAT_DEFAULT
= List.of("java.class", "java.properties");
/**
* The class-only format {@code List} containing
* {@code "java.class"}. This {@code List} is unmodifiable.
*
* @see #getFormats(String)
*/
public static final List<String> FORMAT_CLASS = List.of("java.class");
/**
* The properties-only format {@code List} containing
* {@code "java.properties"}. This {@code List} is unmodifiable.
*
* @see #getFormats(String)
*/
public static final List<String> FORMAT_PROPERTIES
= List.of("java.properties");
/**
* The time-to-live constant for not caching loaded resource bundle
* instances.
*
* @see #getTimeToLive(String, Locale)
*/
public static final long TTL_DONT_CACHE = -1;
/**
* The time-to-live constant for disabling the expiration control
* for loaded resource bundle instances in the cache.
*
* @see #getTimeToLive(String, Locale)
*/
public static final long TTL_NO_EXPIRATION_CONTROL = -2;
private static final Control INSTANCE = new Control();
/**
* Sole constructor. (For invocation by subclass constructors,
* typically implicit.)
*/
protected Control() {
}
/**
* Returns a {@code ResourceBundle.Control} in which the {@link
* #getFormats(String) getFormats} method returns the specified
* {@code formats}. The {@code formats} must be equal to
* one of {@link Control#FORMAT_PROPERTIES}, {@link
* Control#FORMAT_CLASS} or {@link
* Control#FORMAT_DEFAULT}. {@code ResourceBundle.Control}
* instances returned by this method are singletons and thread-safe.
*
* <p>Specifying {@link Control#FORMAT_DEFAULT} is equivalent to
* instantiating the {@code ResourceBundle.Control} class,
* except that this method returns a singleton.
*
* @param formats
* the formats to be returned by the
* {@code ResourceBundle.Control.getFormats} method
* @return a {@code ResourceBundle.Control} supporting the
* specified {@code formats}
* @throws NullPointerException
* if {@code formats} is {@code null}
* @throws IllegalArgumentException
* if {@code formats} is unknown
*/
public static final Control getControl(List<String> formats) {
if (formats.equals(Control.FORMAT_PROPERTIES)) {
return SingleFormatControl.PROPERTIES_ONLY;
}
if (formats.equals(Control.FORMAT_CLASS)) {
return SingleFormatControl.CLASS_ONLY;
}
if (formats.equals(Control.FORMAT_DEFAULT)) {
return Control.INSTANCE;
}
throw new IllegalArgumentException();
}
/**
* Returns a {@code ResourceBundle.Control} in which the {@link
* #getFormats(String) getFormats} method returns the specified
* {@code formats} and the {@link
* Control#getFallbackLocale(String, Locale) getFallbackLocale}
* method returns {@code null}. The {@code formats} must
* be equal to one of {@link Control#FORMAT_PROPERTIES}, {@link
* Control#FORMAT_CLASS} or {@link Control#FORMAT_DEFAULT}.
* {@code ResourceBundle.Control} instances returned by this
* method are singletons and thread-safe.
*
* @param formats
* the formats to be returned by the
* {@code ResourceBundle.Control.getFormats} method
* @return a {@code ResourceBundle.Control} supporting the
* specified {@code formats} with no fallback
* {@code Locale} support
* @throws NullPointerException
* if {@code formats} is {@code null}
* @throws IllegalArgumentException
* if {@code formats} is unknown
*/
public static final Control getNoFallbackControl(List<String> formats) {
if (formats.equals(Control.FORMAT_DEFAULT)) {
return NoFallbackControl.NO_FALLBACK;
}
if (formats.equals(Control.FORMAT_PROPERTIES)) {
return NoFallbackControl.PROPERTIES_ONLY_NO_FALLBACK;
}
if (formats.equals(Control.FORMAT_CLASS)) {
return NoFallbackControl.CLASS_ONLY_NO_FALLBACK;
}
throw new IllegalArgumentException();
}
/**
* Returns a {@code List} of {@code String}s containing
* formats to be used to load resource bundles for the given
* {@code baseName}. The {@code ResourceBundle.getBundle}
* factory method tries to load resource bundles with formats in the
* order specified by the list. The list returned by this method
* must have at least one {@code String}. The predefined
* formats are {@code "java.class"} for class-based resource
* bundles and {@code "java.properties"} for {@linkplain
* PropertyResourceBundle properties-based} ones. Strings starting
* with {@code "java."} are reserved for future extensions and
* must not be used by application-defined formats.
*
* <p>It is not a requirement to return an immutable (unmodifiable)
* {@code List}. However, the returned {@code List} must
* not be mutated after it has been returned by
* {@code getFormats}.
*
* <p>The default implementation returns {@link #FORMAT_DEFAULT} so
* that the {@code ResourceBundle.getBundle} factory method
* looks up first class-based resource bundles, then
* properties-based ones.
*
* @param baseName
* the base name of the resource bundle, a fully qualified class
* name
* @return a {@code List} of {@code String}s containing
* formats for loading resource bundles.
* @throws NullPointerException
* if {@code baseName} is null
* @see #FORMAT_DEFAULT
* @see #FORMAT_CLASS
* @see #FORMAT_PROPERTIES
*/
public List<String> getFormats(String baseName) {
if (baseName == null) {
throw new NullPointerException();
}
return FORMAT_DEFAULT;
}
/**
* Returns a {@code List} of {@code Locale}s as candidate
* locales for {@code baseName} and {@code locale}. This
* method is called by the {@code ResourceBundle.getBundle}
* factory method each time the factory method tries finding a
* resource bundle for a target {@code Locale}.
*
* <p>The sequence of the candidate locales also corresponds to the
* runtime resource lookup path (also known as the <I>parent
* chain</I>), if the corresponding resource bundles for the
* candidate locales exist and their parents are not defined by
* loaded resource bundles themselves. The last element of the list
* must be a {@linkplain Locale#ROOT root locale} if it is desired to
* have the base bundle as the terminal of the parent chain.
*
* <p>If the given locale is equal to {@code Locale.ROOT} (the
* root locale), a {@code List} containing only the root
* {@code Locale} must be returned. In this case, the
* {@code ResourceBundle.getBundle} factory method loads only
* the base bundle as the resulting resource bundle.
*
* <p>It is not a requirement to return an immutable (unmodifiable)
* {@code List}. However, the returned {@code List} must not
* be mutated after it has been returned by
* {@code getCandidateLocales}.
*
* <p>The default implementation returns a {@code List} containing
* {@code Locale}s using the rules described below. In the
* description below, <em>L</em>, <em>S</em>, <em>C</em> and <em>V</em>
* respectively represent non-empty language, script, country, and
* variant. For example, [<em>L</em>, <em>C</em>] represents a
* {@code Locale} that has non-empty values only for language and
* country. The form <em>L</em>("xx") represents the (non-empty)
* language value is "xx". For all cases, {@code Locale}s whose
* final component values are empty strings are omitted.
*
* <ol><li>For an input {@code Locale} with an empty script value,
* append candidate {@code Locale}s by omitting the final component
* one by one as below:
*
* <ul>
* <li> [<em>L</em>, <em>C</em>, <em>V</em>] </li>
* <li> [<em>L</em>, <em>C</em>] </li>
* <li> [<em>L</em>] </li>
* <li> {@code Locale.ROOT} </li>
* </ul></li>
*
* <li>For an input {@code Locale} with a non-empty script value,
* append candidate {@code Locale}s by omitting the final component
* up to language, then append candidates generated from the
* {@code Locale} with country and variant restored:
*
* <ul>
* <li> [<em>L</em>, <em>S</em>, <em>C</em>, <em>V</em>]</li>
* <li> [<em>L</em>, <em>S</em>, <em>C</em>]</li>
* <li> [<em>L</em>, <em>S</em>]</li>
* <li> [<em>L</em>, <em>C</em>, <em>V</em>]</li>
* <li> [<em>L</em>, <em>C</em>]</li>
* <li> [<em>L</em>]</li>
* <li> {@code Locale.ROOT}</li>
* </ul></li>
*
* <li>For an input {@code Locale} with a variant value consisting
* of multiple subtags separated by underscore, generate candidate
* {@code Locale}s by omitting the variant subtags one by one, then
* insert them after every occurrence of {@code Locale}s with the
* full variant value in the original list. For example, if
* the variant consists of two subtags <em>V1</em> and <em>V2</em>:
*
* <ul>
* <li> [<em>L</em>, <em>S</em>, <em>C</em>, <em>V1</em>, <em>V2</em>]</li>
* <li> [<em>L</em>, <em>S</em>, <em>C</em>, <em>V1</em>]</li>
* <li> [<em>L</em>, <em>S</em>, <em>C</em>]</li>
* <li> [<em>L</em>, <em>S</em>]</li>
* <li> [<em>L</em>, <em>C</em>, <em>V1</em>, <em>V2</em>]</li>
* <li> [<em>L</em>, <em>C</em>, <em>V1</em>]</li>
* <li> [<em>L</em>, <em>C</em>]</li>
* <li> [<em>L</em>]</li>
* <li> {@code Locale.ROOT}</li>
* </ul></li>
*
* <li>Special cases for Chinese. When an input {@code Locale} has the
* language "zh" (Chinese) and an empty script value, either "Hans" (Simplified) or
* "Hant" (Traditional) might be supplied, depending on the country.
* When the country is "CN" (China) or "SG" (Singapore), "Hans" is supplied.
* When the country is "HK" (Hong Kong SAR China), "MO" (Macau SAR China),
* or "TW" (Taiwan), "Hant" is supplied. For all other countries or when the country
* is empty, no script is supplied. For example, for <code>Locale("zh", "CN")
* </code>, the candidate list will be:
* <ul>
* <li> [<em>L</em>("zh"), <em>S</em>("Hans"), <em>C</em>("CN")]</li>
* <li> [<em>L</em>("zh"), <em>S</em>("Hans")]</li>
* <li> [<em>L</em>("zh"), <em>C</em>("CN")]</li>
* <li> [<em>L</em>("zh")]</li>
* <li> {@code Locale.ROOT}</li>
* </ul>
*
* For {@code Locale("zh", "TW")}, the candidate list will be:
* <ul>
* <li> [<em>L</em>("zh"), <em>S</em>("Hant"), <em>C</em>("TW")]</li>
* <li> [<em>L</em>("zh"), <em>S</em>("Hant")]</li>
* <li> [<em>L</em>("zh"), <em>C</em>("TW")]</li>
* <li> [<em>L</em>("zh")]</li>
* <li> {@code Locale.ROOT}</li>
* </ul></li>
*
* <li>Special cases for Norwegian. Both {@code Locale("no", "NO",
* "NY")} and {@code Locale("nn", "NO")} represent Norwegian
* Nynorsk. When a locale's language is "nn", the standard candidate
* list is generated up to [<em>L</em>("nn")], and then the following
* candidates are added:
*
* <ul><li> [<em>L</em>("no"), <em>C</em>("NO"), <em>V</em>("NY")]</li>
* <li> [<em>L</em>("no"), <em>C</em>("NO")]</li>
* <li> [<em>L</em>("no")]</li>
* <li> {@code Locale.ROOT}</li>
* </ul>
*
* If the locale is exactly {@code Locale("no", "NO", "NY")}, it is first
* converted to {@code Locale("nn", "NO")} and then the above procedure is
* followed.
*
* <p>Also, Java treats the language "no" as a synonym of Norwegian
* Bokm&#xE5;l "nb". Except for the single case {@code Locale("no",
* "NO", "NY")} (handled above), when an input {@code Locale}
* has language "no" or "nb", candidate {@code Locale}s with
* language code "no" and "nb" are interleaved, first using the
* requested language, then using its synonym. For example,
* {@code Locale("nb", "NO", "POSIX")} generates the following
* candidate list:
*
* <ul>
* <li> [<em>L</em>("nb"), <em>C</em>("NO"), <em>V</em>("POSIX")]</li>
* <li> [<em>L</em>("no"), <em>C</em>("NO"), <em>V</em>("POSIX")]</li>
* <li> [<em>L</em>("nb"), <em>C</em>("NO")]</li>
* <li> [<em>L</em>("no"), <em>C</em>("NO")]</li>
* <li> [<em>L</em>("nb")]</li>
* <li> [<em>L</em>("no")]</li>
* <li> {@code Locale.ROOT}</li>
* </ul>
*
* {@code Locale("no", "NO", "POSIX")} would generate the same list
* except that locales with "no" would appear before the corresponding
* locales with "nb".</li>
* </ol>
*
* <p>The default implementation uses an {@link ArrayList} that
* overriding implementations may modify before returning it to the
* caller. However, a subclass must not modify it after it has
* been returned by {@code getCandidateLocales}.
*
* <p>For example, if the given {@code baseName} is "Messages"
* and the given {@code locale} is
* <code>Locale("ja",&nbsp;"",&nbsp;"XX")</code>, then a
* {@code List} of {@code Locale}s:
* <pre>
* Locale("ja", "", "XX")
* Locale("ja")
* Locale.ROOT
* </pre>
* is returned. And if the resource bundles for the "ja" and
* "" {@code Locale}s are found, then the runtime resource
* lookup path (parent chain) is:
* <pre>{@code
* Messages_ja -> Messages
* }</pre>
*
* @param baseName
* the base name of the resource bundle, a fully
* qualified class name
* @param locale
* the locale for which a resource bundle is desired
* @return a {@code List} of candidate
* {@code Locale}s for the given {@code locale}
* @throws NullPointerException
* if {@code baseName} or {@code locale} is
* {@code null}
*/
public List<Locale> getCandidateLocales(String baseName, Locale locale) {
if (baseName == null) {
throw new NullPointerException();
}
return new ArrayList<>(CANDIDATES_CACHE.computeIfAbsent(locale.getBaseLocale(),
Control::createCandidateList));
}
private static final ReferencedKeyMap<BaseLocale, List<Locale>> CANDIDATES_CACHE = ReferencedKeyMap.create(true, ConcurrentHashMap::new);
private static List<Locale> createCandidateList(BaseLocale base) {
String language = base.getLanguage();
String script = base.getScript();
String region = base.getRegion();
String variant = base.getVariant();
// Special handling for Norwegian
boolean isNorwegianBokmal = false;
boolean isNorwegianNynorsk = false;
if (language.equals("no")) {
if (region.equals("NO") && variant.equals("NY")) {
variant = "";
isNorwegianNynorsk = true;
} else {
isNorwegianBokmal = true;
}
}
if (language.equals("nb") || isNorwegianBokmal) {
List<Locale> tmpList = getDefaultList("nb", script, region, variant);
// Insert a locale replacing "nb" with "no" for every list entry with precedence
List<Locale> bokmalList = new ArrayList<>();
for (Locale l_nb : tmpList) {
var isRoot = l_nb.getLanguage().isEmpty();
var l_no = Locale.getInstance(isRoot ? "" : "no",
l_nb.getScript(), l_nb.getCountry(), l_nb.getVariant(), null);
bokmalList.add(isNorwegianBokmal ? l_no : l_nb);
if (isRoot) {
break;
}
bokmalList.add(isNorwegianBokmal ? l_nb : l_no);
}
return bokmalList;
} else if (language.equals("nn") || isNorwegianNynorsk) {
// Insert no_NO_NY, no_NO, no after nn
List<Locale> nynorskList = getDefaultList("nn", script, region, variant);
int idx = nynorskList.size() - 1;
nynorskList.add(idx++, Locale.getInstance("no", "NO", "NY"));
nynorskList.add(idx++, Locale.getInstance("no", "NO", ""));
nynorskList.add(idx++, Locale.getInstance("no", "", ""));
return nynorskList;
}
// Special handling for Chinese
else if (language.equals("zh")) {
if (script.isEmpty() && !region.isEmpty()) {
// Supply script for users who want to use zh_Hans/zh_Hant
// as bundle names (recommended for Java7+)
switch (region) {
case "TW", "HK", "MO" -> script = "Hant";
case "CN", "SG" -> script = "Hans";
}
}
}
return getDefaultList(language, script, region, variant);
}
private static List<Locale> getDefaultList(String language, String script, String region, String variant) {
List<String> variants = null;
if (!variant.isEmpty()) {
variants = new ArrayList<>();
int idx = variant.length();
while (idx != -1) {
variants.add(variant.substring(0, idx));
idx = variant.lastIndexOf('_', --idx);
}
}
List<Locale> list = new ArrayList<>();
if (variants != null) {
for (String v : variants) {
list.add(Locale.getInstance(language, script, region, v, null));
}
}
if (!region.isEmpty()) {
list.add(Locale.getInstance(language, script, region, "", null));
}
if (!script.isEmpty()) {
list.add(Locale.getInstance(language, script, "", "", null));
// Special handling for Chinese
if (language.equals("zh")) {
if (region.isEmpty()) {
// Supply region(country) for users who still package Chinese
// bundles using old convention.
switch (script) {
case "Hans" -> region = "CN";
case "Hant" -> region = "TW";
}
}
}
// With script, after truncating variant, region and script,
// start over without script.
if (variants != null) {
for (String v : variants) {
list.add(Locale.getInstance(language, "", region, v, null));
}
}
if (!region.isEmpty()) {
list.add(Locale.getInstance(language, "", region, "", null));
}
}
if (!language.isEmpty()) {
list.add(Locale.getInstance(language, "", "", "", null));
}
// Add root locale at the end
list.add(Locale.ROOT);
return list;
}
/**
* Returns a {@code Locale} to be used as a fallback locale for
* further resource bundle searches by the
* {@code ResourceBundle.getBundle} factory method. This method
* is called from the factory method every time when no resulting
* resource bundle has been found for {@code baseName} and
* {@code locale}, where locale is either the parameter for
* {@code ResourceBundle.getBundle} or the previous fallback
* locale returned by this method.
*
* <p>The method returns {@code null} if no further fallback
* search is desired.
*
* <p>The default implementation returns the {@linkplain
* Locale#getDefault() default {@code Locale}} if the given
* {@code locale} isn't the default one. Otherwise,
* {@code null} is returned.
*
* @param baseName
* the base name of the resource bundle, a fully
* qualified class name for which
* {@code ResourceBundle.getBundle} has been
* unable to find any resource bundles (except for the
* base bundle)
* @param locale
* the {@code Locale} for which
* {@code ResourceBundle.getBundle} has been
* unable to find any resource bundles (except for the
* base bundle)
* @return a {@code Locale} for the fallback search,
* or {@code null} if no further fallback search
* is desired.
* @throws NullPointerException
* if {@code baseName} or {@code locale}
* is {@code null}
*/
public Locale getFallbackLocale(String baseName, Locale locale) {
if (baseName == null) {
throw new NullPointerException();
}
Locale defaultLocale = Locale.getDefault();
return locale.equals(defaultLocale) ? null : defaultLocale;
}
/**
* Instantiates a resource bundle for the given bundle name of the
* given format and locale, using the given class loader if
* necessary. This method returns {@code null} if there is no
* resource bundle available for the given parameters. If a resource
* bundle can't be instantiated due to an unexpected error, the
* error must be reported by throwing an {@code Error} or
* {@code Exception} rather than simply returning
* {@code null}.
*
* <p>If the {@code reload} flag is {@code true}, it
* indicates that this method is being called because the previously
* loaded resource bundle has expired.
*
* @implSpec
*
* Resource bundles in named modules are subject to the encapsulation
* rules specified by {@link Module#getResourceAsStream Module.getResourceAsStream}.
* A resource bundle in a named module visible to the given class loader
* is accessible when the package of the resource file corresponding
* to the resource bundle is open unconditionally.
*
* <p>The default implementation instantiates a
* {@code ResourceBundle} as follows.
*
* <ul>
*
* <li>The bundle name is obtained by calling {@link
* #toBundleName(String, Locale) toBundleName(baseName,
* locale)}.</li>
*
* <li>If {@code format} is {@code "java.class"}, the
* {@link Class} specified by the bundle name is loaded with the
* given class loader. If the {@code Class} is found and accessible
* then the {@code ResourceBundle} is instantiated. The
* resource bundle is accessible if the package of the bundle class file
* is open unconditionally; otherwise, {@code IllegalAccessException}
* will be thrown.
* Note that the {@code reload} flag is ignored for loading
* class-based resource bundles in this default implementation.
* </li>
*
* <li>If {@code format} is {@code "java.properties"},
* {@link #toResourceName(String, String) toResourceName(bundlename,
* "properties")} is called to get the resource name.
* If {@code reload} is {@code true}, {@link
* ClassLoader#getResource(String) load.getResource} is called
* to get a {@link URL} for creating a {@link
* URLConnection}. This {@code URLConnection} is used to
* {@linkplain URLConnection#setUseCaches(boolean) disable the
* caches} of the underlying resource loading layers,
* and to {@linkplain URLConnection#getInputStream() get an
* {@code InputStream}}.
* Otherwise, {@link ClassLoader#getResourceAsStream(String)
* loader.getResourceAsStream} is called to get an {@link
* InputStream}. Then, a {@link
* PropertyResourceBundle} is constructed with the
* {@code InputStream}.</li>
*
* <li>If {@code format} is neither {@code "java.class"}
* nor {@code "java.properties"}, an
* {@code IllegalArgumentException} is thrown.</li>
*
* <li>If the {@code locale}'s language is one of the
* <a href="./Locale.html#legacy_language_codes">Legacy language
* codes</a>, either old or new, then repeat the loading process
* if needed, with the bundle name with the other language.
* For example, "iw" for "he" and vice versa.
*
* </ul>
*
* @param baseName
* the base bundle name of the resource bundle, a fully
* qualified class name
* @param locale
* the locale for which the resource bundle should be
* instantiated
* @param format
* the resource bundle format to be loaded
* @param loader
* the {@code ClassLoader} to use to load the bundle
* @param reload
* the flag to indicate bundle reloading; {@code true}
* if reloading an expired resource bundle,
* {@code false} otherwise
* @return the resource bundle instance,
* or {@code null} if none could be found.
* @throws NullPointerException
* if {@code bundleName}, {@code locale},
* {@code format}, or {@code loader} is
* {@code null}, or if {@code null} is returned by
* {@link #toBundleName(String, Locale) toBundleName}
* @throws IllegalArgumentException
* if {@code format} is unknown, or if the resource
* found for the given parameters contains malformed data.
* @throws ClassCastException
* if the loaded class cannot be cast to {@code ResourceBundle}
* @throws IllegalAccessException
* if the class or its nullary constructor is not
* accessible.
* @throws InstantiationException
* if the instantiation of a class fails for some other
* reason.
* @throws ExceptionInInitializerError
* if the initialization provoked by this method fails.
* @throws IOException
* if an error occurred when reading resources using
* any I/O operations
* @see java.util.spi.ResourceBundleProvider#getBundle(String, Locale)
*/
public ResourceBundle newBundle(String baseName, Locale locale, String format,
ClassLoader loader, boolean reload)
throws IllegalAccessException, InstantiationException, IOException {
/*
* Legacy mechanism to locate resource bundle in unnamed module only
* that is visible to the given loader and accessible to the given caller.
*/
String bundleName = toBundleName(baseName, locale);
var bundle = newBundle0(bundleName, format, loader, reload);
if (bundle == null) {
// Try loading legacy ISO language's other bundles
var otherBundleName = Bundles.toOtherBundleName(baseName, bundleName, locale);
if (!bundleName.equals(otherBundleName)) {
bundle = newBundle0(otherBundleName, format, loader, reload);
}
}
return bundle;
}
private ResourceBundle newBundle0(String bundleName, String format,
ClassLoader loader, boolean reload)
throws IllegalAccessException, InstantiationException, IOException {
ResourceBundle bundle = null;
if (format.equals("java.class")) {
try {
Class<?> c = loader.loadClass(bundleName);
// If the class isn't a ResourceBundle subclass, throw a
// ClassCastException.
if (ResourceBundle.class.isAssignableFrom(c)) {
@SuppressWarnings("unchecked")
Class<ResourceBundle> bundleClass = (Class<ResourceBundle>)c;
Module m = bundleClass.getModule();
// To access a resource bundle in a named module,
// either class-based or properties-based, the resource
// bundle must be opened unconditionally,
// same rule as accessing a resource file.
if (m.isNamed() && !m.isOpen(bundleClass.getPackageName())) {
throw new IllegalAccessException("unnamed module can't load " +
bundleClass.getName() + " in " + m.toString());
}
try {
Constructor<ResourceBundle> ctor = bundleClass.getDeclaredConstructor();
if (!Modifier.isPublic(ctor.getModifiers())) {
throw new IllegalAccessException("no-arg constructor in " +
bundleClass.getName() + " is not publicly accessible.");
}
// java.base may not be able to read the bundleClass's module.
ctor.setAccessible(true);
bundle = ctor.newInstance((Object[]) null);
} catch (InvocationTargetException e) {
uncheckedThrow(e);
} catch (NoSuchMethodException e) {
throw new InstantiationException("public no-arg constructor " +
"does not exist in " + bundleClass.getName());
}
} else {
throw new ClassCastException(c.getName()
+ " cannot be cast to ResourceBundle");
}
} catch (ClassNotFoundException e) {
}
} else if (format.equals("java.properties")) {
final String resourceName = toResourceName0(bundleName, "properties");
if (resourceName == null) {
return bundle;
}
URL url = loader.getResource(resourceName);
if (url == null) return null;
URLConnection connection = url.openConnection();
if (reload) {
// Disable caches to get fresh data for
// reloading.
connection.setUseCaches(false);
}
InputStream stream = connection.getInputStream();
if (stream != null) {
try {
bundle = new PropertyResourceBundle(stream);
} finally {
stream.close();
}
}
} else {
throw new IllegalArgumentException("unknown format: " + format);
}
return bundle;
}
/**
* Returns the time-to-live (TTL) value for resource bundles that
* are loaded under this
* {@code ResourceBundle.Control}. Positive time-to-live values
* specify the number of milliseconds a bundle can remain in the
* cache without being validated against the source data from which
* it was constructed. The value 0 indicates that a bundle must be
* validated each time it is retrieved from the cache. {@link
* #TTL_DONT_CACHE} specifies that loaded resource bundles are not
* put in the cache. {@link #TTL_NO_EXPIRATION_CONTROL} specifies
* that loaded resource bundles are put in the cache with no
* expiration control.
*
* <p>The expiration affects only the bundle loading process by the
* {@code ResourceBundle.getBundle} factory method. That is,
* if the factory method finds a resource bundle in the cache that
* has expired, the factory method calls the {@link
* #needsReload(String, Locale, String, ClassLoader, ResourceBundle,
* long) needsReload} method to determine whether the resource
* bundle needs to be reloaded. If {@code needsReload} returns
* {@code true}, the cached resource bundle instance is removed
* from the cache. Otherwise, the instance stays in the cache,
* updated with the new TTL value returned by this method.
*
* <p>All cached resource bundles are subject to removal from the
* cache due to memory constraints of the runtime environment.
* Returning a large positive value doesn't mean to lock loaded
* resource bundles in the cache.
*
* <p>The default implementation returns {@link #TTL_NO_EXPIRATION_CONTROL}.
*
* @param baseName
* the base name of the resource bundle for which the
* expiration value is specified.
* @param locale
* the locale of the resource bundle for which the
* expiration value is specified.
* @return the time (0 or a positive millisecond offset from the
* cached time) to get loaded bundles expired in the cache,
* {@link #TTL_NO_EXPIRATION_CONTROL} to disable the
* expiration control, or {@link #TTL_DONT_CACHE} to disable
* caching.
* @throws NullPointerException
* if {@code baseName} or {@code locale} is
* {@code null}
*/
public long getTimeToLive(String baseName, Locale locale) {
if (baseName == null || locale == null) {
throw new NullPointerException();
}
return TTL_NO_EXPIRATION_CONTROL;
}
/**
* Determines if the expired {@code bundle} in the cache needs
* to be reloaded based on the loading time given by
* {@code loadTime} or some other criteria. The method returns
* {@code true} if reloading is required; {@code false}
* otherwise. {@code loadTime} is a millisecond offset since
* the <a href="Calendar.html#Epoch"> {@code Calendar}
* Epoch</a>.
*
* <p>
* The calling {@code ResourceBundle.getBundle} factory method
* calls this method on the {@code ResourceBundle.Control}
* instance used for its current invocation, not on the instance
* used in the invocation that originally loaded the resource
* bundle.
*
* <p>The default implementation compares {@code loadTime} and
* the last modified time of the source data of the resource
* bundle. If it's determined that the source data has been modified
* since {@code loadTime}, {@code true} is
* returned. Otherwise, {@code false} is returned. This
* implementation assumes that the given {@code format} is the
* same string as its file suffix if it's not one of the default
* formats, {@code "java.class"} or
* {@code "java.properties"}.
*
* @param baseName
* the base bundle name of the resource bundle, a
* fully qualified class name
* @param locale
* the locale for which the resource bundle
* should be instantiated
* @param format
* the resource bundle format to be loaded
* @param loader
* the {@code ClassLoader} to use to load the bundle
* @param bundle
* the resource bundle instance that has been expired
* in the cache
* @param loadTime
* the time when {@code bundle} was loaded and put
* in the cache
* @return {@code true} if the expired bundle needs to be
* reloaded; {@code false} otherwise.
* @throws NullPointerException
* if {@code baseName}, {@code locale},
* {@code format}, {@code loader}, or
* {@code bundle} is {@code null}
*/
public boolean needsReload(String baseName, Locale locale,
String format, ClassLoader loader,
ResourceBundle bundle, long loadTime) {
if (bundle == null) {
throw new NullPointerException();
}
if (format.equals("java.class") || format.equals("java.properties")) {
format = format.substring(5);
}
boolean result = false;
try {
String resourceName = toResourceName0(toBundleName(baseName, locale), format);
if (resourceName == null) {
return result;
}
URL url = loader.getResource(resourceName);
if (url != null) {
long lastModified = 0;
URLConnection connection = url.openConnection();
if (connection != null) {
// disable caches to get the correct data
connection.setUseCaches(false);
if (connection instanceof JarURLConnection) {
JarEntry ent = ((JarURLConnection)connection).getJarEntry();
if (ent != null) {
lastModified = ent.getTime();
if (lastModified == -1) {
lastModified = 0;
}
}
} else {
lastModified = connection.getLastModified();
}
}
result = lastModified >= loadTime;
}
} catch (NullPointerException npe) {
throw npe;
} catch (Exception e) {
// ignore other exceptions
}
return result;
}
/**
* Converts the given {@code baseName} and {@code locale}
* to the bundle name. This method is called from the default
* implementation of the {@link #newBundle(String, Locale, String,
* ClassLoader, boolean) newBundle} and {@link #needsReload(String,
* Locale, String, ClassLoader, ResourceBundle, long) needsReload}
* methods.
*
* <p>This implementation returns the following value:
* <pre>
* baseName + "_" + language + "_" + script + "_" + country + "_" + variant
* </pre>
* where {@code language}, {@code script}, {@code country},
* and {@code variant} are the language, script, country, and variant
* values of {@code locale}, respectively. Final component values that
* are empty Strings are omitted along with the preceding '_'. When the
* script is empty, the script value is omitted along with the preceding '_'.
* If all of the values are empty strings, then {@code baseName}
* is returned.
*
* <p>For example, if {@code baseName} is
* {@code "baseName"} and {@code locale} is
* <code>Locale("ja",&nbsp;"",&nbsp;"XX")</code>, then
* <code>"baseName_ja_&thinsp;_XX"</code> is returned. If the given
* locale is {@code Locale("en")}, then
* {@code "baseName_en"} is returned.
*
* <p>Overriding this method allows applications to use different
* conventions in the organization and packaging of localized
* resources.
*
* @param baseName
* the base name of the resource bundle, a fully
* qualified class name
* @param locale
* the locale for which a resource bundle should be
* loaded
* @return the bundle name for the resource bundle
* @throws NullPointerException
* if {@code baseName} or {@code locale}
* is {@code null}
* @see java.util.spi.AbstractResourceBundleProvider#toBundleName(String, Locale)
*/
public String toBundleName(String baseName, Locale locale) {
if (locale == Locale.ROOT) {
return baseName;
}
String language = locale.getLanguage();
String script = locale.getScript();
String country = locale.getCountry();
String variant = locale.getVariant();
if (language == "" && country == "" && variant == "") {
return baseName;
}
StringBuilder sb = new StringBuilder(baseName);
sb.append('_');
if (script != "") {
if (variant != "") {
sb.append(language).append('_').append(script).append('_').append(country).append('_').append(variant);
} else if (country != "") {
sb.append(language).append('_').append(script).append('_').append(country);
} else {
sb.append(language).append('_').append(script);
}
} else {
if (variant != "") {
sb.append(language).append('_').append(country).append('_').append(variant);
} else if (country != "") {
sb.append(language).append('_').append(country);
} else {
sb.append(language);
}
}
return sb.toString();
}
/**
* Converts the given {@code bundleName} to the form required
* by the {@link ClassLoader#getResource ClassLoader.getResource}
* method by replacing all occurrences of {@code '.'} in
* {@code bundleName} with {@code '/'} and appending a
* {@code '.'} and the given file {@code suffix}. For
* example, if {@code bundleName} is
* {@code "foo.bar.MyResources_ja_JP"} and {@code suffix}
* is {@code "properties"}, then
* {@code "foo/bar/MyResources_ja_JP.properties"} is returned.
*
* @param bundleName
* the bundle name
* @param suffix
* the file type suffix
* @return the converted resource name
* @throws NullPointerException
* if {@code bundleName} or {@code suffix}
* is {@code null}
*/
public final String toResourceName(String bundleName, String suffix) {
StringBuilder sb = new StringBuilder(bundleName.length() + 1 + suffix.length());
sb.append(bundleName.replace('.', '/')).append('.').append(suffix);
return sb.toString();
}
private String toResourceName0(String bundleName, String suffix) {
// application protocol check
if (bundleName.contains("://")) {
return null;
} else {
return toResourceName(bundleName, suffix);
}
}
}
@SuppressWarnings("unchecked")
private static <T extends Throwable> void uncheckedThrow(Throwable t) throws T {
if (t != null)
throw (T)t;
else
throw new Error("Unknown Exception");
}
private static class SingleFormatControl extends Control {
private static final Control PROPERTIES_ONLY
= new SingleFormatControl(FORMAT_PROPERTIES);
private static final Control CLASS_ONLY
= new SingleFormatControl(FORMAT_CLASS);
private final List<String> formats;
protected SingleFormatControl(List<String> formats) {
this.formats = formats;
}
public List<String> getFormats(String baseName) {
if (baseName == null) {
throw new NullPointerException();
}
return formats;
}
}
private static final class NoFallbackControl extends SingleFormatControl {
private static final Control NO_FALLBACK
= new NoFallbackControl(FORMAT_DEFAULT);
private static final Control PROPERTIES_ONLY_NO_FALLBACK
= new NoFallbackControl(FORMAT_PROPERTIES);
private static final Control CLASS_ONLY_NO_FALLBACK
= new NoFallbackControl(FORMAT_CLASS);
protected NoFallbackControl(List<String> formats) {
super(formats);
}
public Locale getFallbackLocale(String baseName, Locale locale) {
if (baseName == null || locale == null) {
throw new NullPointerException();
}
return null;
}
}
private static class ResourceBundleProviderHelper {
/**
* Returns a new ResourceBundle instance of the given bundleClass
*/
static ResourceBundle newResourceBundle(Class<? extends ResourceBundle> bundleClass) {
try {
Constructor<? extends ResourceBundle> ctor =
bundleClass.getConstructor();
if (!Modifier.isPublic(ctor.getModifiers())) {
return null;
}
// java.base may not be able to read the bundleClass's module.
ctor.setAccessible(true);
try {
return ctor.newInstance((Object[]) null);
} catch (InvocationTargetException e) {
uncheckedThrow(e);
} catch (InstantiationException | IllegalAccessException e) {
throw new InternalError(e);
}
} catch (NoSuchMethodException e) {
throw new InternalError(e);
}
return null;
}
/**
* Loads a {@code ResourceBundle} of the given {@code bundleName} local to
* the given {@code module}. If not found, search the bundle class
* that is visible from the module's class loader.
*
* The caller module is used for access check only.
*/
static ResourceBundle loadResourceBundle(Module callerModule,
Module module,
String baseName,
Locale locale)
{
String bundleName = Control.INSTANCE.toBundleName(baseName, locale);
try {
Class<?> c = Class.forName(module, bundleName);
trace("local in %s %s caller %s: %s%n", module, bundleName, callerModule, c);
if (c == null) {
// if not found from the given module, locate resource bundle
// that is visible to the module's class loader
ClassLoader loader = getLoader(module);
if (loader != null) {
c = Class.forName(bundleName, false, loader);
} else {
c = BootLoader.loadClassOrNull(bundleName);
}
trace("loader for %s %s caller %s: %s%n", module, bundleName, callerModule, c);
}
if (c != null && ResourceBundle.class.isAssignableFrom(c)) {
@SuppressWarnings("unchecked")
Class<ResourceBundle> bundleClass = (Class<ResourceBundle>) c;
Module m = bundleClass.getModule();
if (!isAccessible(callerModule, m, bundleClass.getPackageName())) {
trace(" %s does not have access to %s/%s%n", callerModule,
m.getName(), bundleClass.getPackageName());
return null;
}
return newResourceBundle(bundleClass);
}
} catch (ClassNotFoundException e) {}
return null;
}
/**
* Tests if resources of the given package name from the given module are
* open to the caller module.
*/
static boolean isAccessible(Module callerModule, Module module, String pn) {
if (!module.isNamed() || callerModule == module)
return true;
return module.isOpen(pn, callerModule);
}
/**
* Loads properties of the given {@code bundleName} local in the given
* {@code module}. If the .properties is not found or not open
* to the caller module to access, it will find the resource that
* is visible to the module's class loader.
*
* The caller module is used for access check only.
*/
static ResourceBundle loadPropertyResourceBundle(Module callerModule,
Module module,
String baseName,
Locale locale)
throws IOException
{
String bundleName = Control.INSTANCE.toBundleName(baseName, locale);
String resourceName = Control.INSTANCE
.toResourceName0(bundleName, "properties");
if (resourceName == null) {
return null;
}
trace("local in %s %s caller %s%n", module, resourceName, callerModule);
// if the package is in the given module but not opened
// locate it from the given module first.
String pn = toPackageName(bundleName);
trace(" %s/%s is accessible to %s : %s%n",
module.getName(), pn, callerModule,
isAccessible(callerModule, module, pn));
if (isAccessible(callerModule, module, pn)) {
InputStream in = module.getResourceAsStream(resourceName);
if (in != null) {
return new PropertyResourceBundle(in);
}
}
ClassLoader loader = module.getClassLoader();
trace("loader for %s %s caller %s%n", module, resourceName, callerModule);
try {
InputStream stream = null;
if (loader != null) {
stream = loader.getResourceAsStream(resourceName);
} else {
URL url = BootLoader.findResource(resourceName);
if (url != null) {
stream = url.openStream();
}
}
if (stream != null) {
return new PropertyResourceBundle(stream);
} else {
return null;
}
} catch (Exception e) {
return null;
}
}
private static String toPackageName(String bundleName) {
int i = bundleName.lastIndexOf('.');
return i != -1 ? bundleName.substring(0, i) : "";
}
}
private static final boolean TRACE_ON = Boolean.getBoolean("resource.bundle.debug");
private static void trace(String format, Object... params) {
if (TRACE_ON)
System.out.format(format, params);
}
}