Module java.base
Package java.util.spi

Class AbstractResourceBundleProvider

java.lang.Object
java.util.spi.AbstractResourceBundleProvider
All Implemented Interfaces:
ResourceBundleProvider
public abstract class AbstractResourceBundleProvider
extends Object
implements ResourceBundleProvider
AbstractResourceBundleProvider is an abstract class that provides the basic support for a provider implementation class for ResourceBundleProvider.

Resource bundles can be packaged in one or more named modules, service provider modules. The consumer of the resource bundle is the one calling ResourceBundle.getBundle(String). In order for the consumer module to load a resource bundle "com.example.app.MyResources" provided by another module, it will use the service loader mechanism. A service interface named "com.example.app.spi.MyResourcesProvider" must be defined and a service provider module will provide an implementation class of "com.example.app.spi.MyResourcesProvider" as follows: 

 import com.example.app.spi.MyResourcesProvider;
 class MyResourcesProviderImpl extends AbstractResourceBundleProvider
     implements MyResourcesProvider
 {
     public MyResourcesProviderImpl() {
         super("java.properties");
     }
     // this provider maps the resource bundle to per-language package
     protected String toBundleName(String baseName, Locale locale) {
         return "p." + locale.getLanguage() + "." + baseName;
     }

     public ResourceBundle getBundle(String baseName, Locale locale) {
         // this module only provides bundles in French
         if (locale.equals(Locale.FRENCH)) {
              return super.getBundle(baseName, locale);
         }
         // otherwise return null
         return null;
     }
 }
Refer to ResourceBundleProvider for details.

Since:
9
See Also:
Resource Bundles and Named Modules

  • Constructor Details

    • AbstractResourceBundleProvider

      protected AbstractResourceBundleProvider()
      Constructs an AbstractResourceBundleProvider with the "java.properties" format. This constructor is equivalent to AbstractResourceBundleProvider("java.properties").

    • AbstractResourceBundleProvider

      protected AbstractResourceBundleProvider​(String... formats)
      Constructs an AbstractResourceBundleProvider with the specified formats. The getBundle(String, Locale) method looks up resource bundles for the given formats. formats must be "java.class" or "java.properties".
      Parameters:
      formats - the formats to be used for loading resource bundles
      Throws:
      NullPointerException - if the given formats is null
      IllegalArgumentException - if the given formats is not "java.class" or "java.properties".

  • Method Details

    • toBundleName

      protected String toBundleName​(String baseName, Locale locale)
      Returns the bundle name for the given baseName and locale that this provider provides.
      API Note:
      A resource bundle provider may package its resource bundles in the same package as the base name of the resource bundle if the package is not split among other named modules. If there are more than one bundle providers providing the resource bundle of a given base name, the resource bundles can be packaged with per-language grouping or per-region grouping to eliminate the split packages.

      For example, if baseName is "p.resources.Bundle" then the resource bundle name of "p.resources.Bundle" of Locale("ja", "", "XX") and Locale("en") could be "p.resources.ja.Bundle_ja_ _XX" and "p.resources.Bundle_en" respectively.

      This method is called from the default implementation of the getBundle(String, Locale) method.

      Implementation Note:
      The default implementation of this method is the same as the implementation of ResourceBundle.Control.toBundleName(String, Locale).
      Parameters:
      baseName - the base name of the resource bundle, a fully qualified class name
      locale - the locale for which a resource bundle should be loaded
      Returns:
      the bundle name for the resource bundle

    • getBundle

      public ResourceBundle getBundle​(String baseName, Locale locale)
      Returns a ResourceBundle for the given baseName and locale.
      Specified by:
      getBundle in interface ResourceBundleProvider
      Implementation Note:
      The default implementation of this method calls the toBundleName method to get the bundle name for the baseName and locale and finds the resource bundle of the bundle name local in the module of this provider. It will only search the formats specified when this provider was constructed.
      Parameters:
      baseName - the base bundle name of the resource bundle, a fully qualified class name.
      locale - the locale for which the resource bundle should be instantiated
      Returns:
      ResourceBundle of the given baseName and locale, or null if no resource bundle is found
      Throws:
      NullPointerException - if baseName or locale is null
      UncheckedIOException - if any IO exception occurred during resource bundle loading