jdk/src/java.base/share/classes/java/util/ResourceBundle.java
changeset 43337 e107e6921357
parent 43189 d37bfddf7c38
child 43712 5dfd0950317c
--- a/jdk/src/java.base/share/classes/java/util/ResourceBundle.java	Mon Jan 30 11:00:18 2017 -0800
+++ b/jdk/src/java.base/share/classes/java/util/ResourceBundle.java	Mon Jan 30 14:38:08 2017 -0800
@@ -61,7 +61,10 @@
 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.Collectors;
+import java.util.stream.Stream;
 
 import jdk.internal.loader.BootLoader;
 import jdk.internal.misc.JavaUtilResourceBundleAccess;
@@ -232,6 +235,8 @@
  * <li>{@code ResourceBundle.Control} is <em>not</em> supported in named modules.
  * If the {@code getBundle} method with a {@code ResourceBundle.Control} is called
  * in a named module, the method will throw an {@code UnsupportedOperationException}.
+ * Any service providers of {@link ResourceBundleControlProvider} are ignored in
+ * named modules.
  * </li>
  * </ul>
  *
@@ -262,6 +267,18 @@
  * {@link #getBundle(String, Locale, ClassLoader, Control) getBundle}
  * factory method for details.
  *
+ * <p><a name="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.
+ *
  * <h3>Cache Management</h3>
  *
  * Resource bundle instances created by the <code>getBundle</code> factory
@@ -367,7 +384,8 @@
                 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, Control.INSTANCE);
+                                         baseName, locale,
+                                         getDefaultControl(module, baseName));
                 }
 
                 @Override
@@ -815,7 +833,7 @@
     {
         Class<?> caller = Reflection.getCallerClass();
         return getBundleImpl(baseName, Locale.getDefault(),
-                             caller, Control.INSTANCE);
+                             caller, getDefaultControl(caller, baseName));
     }
 
     /**
@@ -889,7 +907,7 @@
     {
         Class<?> caller = Reflection.getCallerClass();
         return getBundleImpl(baseName, locale,
-                             caller, Control.INSTANCE);
+                             caller, getDefaultControl(caller, baseName));
     }
 
     /**
@@ -925,7 +943,8 @@
     @CallerSensitive
     public static ResourceBundle getBundle(String baseName, Module module) {
         return getBundleFromModule(Reflection.getCallerClass(), module, baseName,
-                                   Locale.getDefault(), Control.INSTANCE);
+                                   Locale.getDefault(),
+                                   getDefaultControl(module, baseName));
     }
 
     /**
@@ -953,7 +972,9 @@
      * 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.
+     * 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
@@ -974,7 +995,7 @@
     @CallerSensitive
     public static ResourceBundle getBundle(String baseName, Locale targetLocale, Module module) {
         return getBundleFromModule(Reflection.getCallerClass(), module, baseName, targetLocale,
-                                   Control.INSTANCE);
+                                   getDefaultControl(module, baseName));
     }
 
     /**
@@ -1030,7 +1051,10 @@
      *
      * <p>This method behaves the same as calling
      * {@link #getBundle(String, Locale, ClassLoader, Control)} passing a
-     * default instance of {@link Control}.
+     * default instance of {@link Control} unless another {@link Control} is
+     * provided with the {@link ResourceBundleControlProvider} SPI. Refer to the
+     * description of <a href="#modify_default_behavior">modifying the default
+     * behavior</a>.
      *
      * <p><a name="default_behavior">The following describes the default
      * behavior</a>.
@@ -1228,7 +1252,7 @@
             throw new NullPointerException();
         }
         Class<?> caller = Reflection.getCallerClass();
-        return getBundleImpl(baseName, locale, caller, loader, Control.INSTANCE);
+        return getBundleImpl(baseName, locale, caller, loader, getDefaultControl(caller, baseName));
     }
 
     /**
@@ -1453,6 +1477,39 @@
         return getBundleImpl(baseName, targetLocale, caller, loader, control);
     }
 
+    private static Control getDefaultControl(Class<?> caller, String baseName) {
+        return getDefaultControl(caller.getModule(), baseName);
+    }
+
+    private static Control getDefaultControl(Module targetModule, String baseName) {
+        return targetModule.isNamed() ?
+            Control.INSTANCE :
+            ResourceBundleControlProviderHolder.getControl(baseName);
+    }
+
+    private static class ResourceBundleControlProviderHolder {
+        private static final PrivilegedAction<List<ResourceBundleControlProvider>> pa =
+            () -> {
+                return Collections.unmodifiableList(
+                    ServiceLoader.load(ResourceBundleControlProvider.class,
+                                       ClassLoader.getSystemClassLoader()).stream()
+                        .map(ServiceLoader.Provider::get)
+                        .collect(Collectors.toList()));
+            };
+
+        private static final List<ResourceBundleControlProvider> CONTROL_PROVIDERS =
+            AccessController.doPrivileged(pa);
+
+        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) {
         if (caller.getModule().isNamed()) {
             throw new UnsupportedOperationException(
@@ -2414,7 +2471,8 @@
      * @apiNote <a name="note">{@code ResourceBundle.Control} is not supported
      * in named modules.</a> If the {@code ResourceBundle.getBundle} method with
      * a {@code ResourceBundle.Control} is called in a named module, the method
-     * will throw an {@link UnsupportedOperationException}.
+     * will throw an {@link UnsupportedOperationException}. Any service providers
+     * of {@link ResourceBundleControlProvider} are ignored in named modules.
      *
      * @since 1.6
      * @see java.util.spi.ResourceBundleProvider