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java.util

Class ResourceBundle

    • Field Detail

      • parent

        protected ResourceBundle parent
        The parent bundle. This is consulted when you call getObject and there is no such resource in the current bundle. This field may be null.
    • Constructor Detail

      • ResourceBundle

        public ResourceBundle()
        The constructor. It does nothing special.
    • Method Detail

      • getString

        public final String getString(String key)
        Get a String from this resource bundle. Since most localized Objects are Strings, this method provides a convenient way to get them without casting.
        Parameters:
        key - the name of the resource
        Throws:
        MissingResourceException - if the resource can't be found
        NullPointerException - if key is null
        ClassCastException - if resource is not a string
      • getStringArray

        public final String[] getStringArray(String key)
        Get an array of Strings from this resource bundle. This method provides a convenient way to get it without casting.
        Parameters:
        key - the name of the resource
        Throws:
        MissingResourceException - if the resource can't be found
        NullPointerException - if key is null
        ClassCastException - if resource is not a string
      • getObject

        public final Object getObject(String key)
        Get an object from this resource bundle. This will call handleGetObject for this resource and all of its parents, until it finds a non-null resource.
        Parameters:
        key - the name of the resource
        Throws:
        MissingResourceException - if the resource can't be found
        NullPointerException - if key is null
      • getLocale

        public Locale getLocale()
        Return the actual locale of this bundle. You can use it after calling getBundle, to know if the bundle for the desired locale was loaded or if the fall back was used.
        Returns:
        the bundle's locale
      • setParent

        protected void setParent(ResourceBundle parent)
        Set the parent of this bundle. The parent is consulted when you call getObject and there is no such resource in the current bundle.
        Parameters:
        parent - the parent of this bundle
      • getBundle

        public static final ResourceBundle getBundle(String baseName)
        Get the appropriate ResourceBundle for the default locale. This is like calling getBundle(baseName, Locale.getDefault(), getClass().getClassLoader(), except that any security check of getClassLoader won't fail.
        Parameters:
        baseName - the name of the ResourceBundle
        Returns:
        the desired resource bundle
        Throws:
        MissingResourceException - if the resource bundle can't be found
        NullPointerException - if baseName is null
      • getBundle

        public static final ResourceBundle getBundle(String baseName,
                                                     Locale locale)
        Get the appropriate ResourceBundle for the given locale. This is like calling getBundle(baseName, locale, getClass().getClassLoader(), except that any security check of getClassLoader won't fail.
        Parameters:
        baseName - the name of the ResourceBundle
        locale - A locale
        Returns:
        the desired resource bundle
        Throws:
        MissingResourceException - if the resource bundle can't be found
        NullPointerException - if baseName or locale is null
      • getBundle

        public static final ResourceBundle getBundle(String baseName,
                                                     Locale locale,
                                                     ClassLoader classLoader)
        Get the appropriate ResourceBundle for the given locale. The following strategy is used:

        A sequence of candidate bundle names are generated, and tested in this order, where the suffix 1 means the string from the specified locale, and the suffix 2 means the string from the default locale:

        • baseName + "_" + language1 + "_" + country1 + "_" + variant1
        • baseName + "_" + language1 + "_" + country1
        • baseName + "_" + language1
        • baseName + "_" + language2 + "_" + country2 + "_" + variant2
        • baseName + "_" + language2 + "_" + country2
        • baseName + "_" + language2
        • baseName

        In the sequence, entries with an empty string are ignored. Next, getBundle tries to instantiate the resource bundle:

        • First, an attempt is made to load a class in the specified classloader which is a subclass of ResourceBundle, and which has a public constructor with no arguments, via reflection.
        • Next, a search is made for a property resource file, by replacing '.' with '/' and appending ".properties", and using ClassLoader.getResource(). If a file is found, then a PropertyResourceBundle is created from the file's contents.
        If no resource bundle was found, a MissingResourceException is thrown.

        Next, the parent chain is implemented. The remaining candidate names in the above sequence are tested in a similar manner, and if any results in a resource bundle, it is assigned as the parent of the first bundle using the setParent method (unless the first bundle already has a parent).

        For example, suppose the following class and property files are provided: MyResources.class, MyResources_fr_CH.properties, MyResources_fr_CH.class, MyResources_fr.properties, MyResources_en.properties, and MyResources_es_ES.class. The contents of all files are valid (that is, public non-abstract subclasses of ResourceBundle with public nullary constructors for the ".class" files, syntactically correct ".properties" files). The default locale is Locale("en", "UK").

        Calling getBundle with the shown locale argument values instantiates resource bundles from the following sources:

        • Locale("fr", "CH"): result MyResources_fr_CH.class, parent MyResources_fr.properties, parent MyResources.class
        • Locale("fr", "FR"): result MyResources_fr.properties, parent MyResources.class
        • Locale("de", "DE"): result MyResources_en.properties, parent MyResources.class
        • Locale("en", "US"): result MyResources_en.properties, parent MyResources.class
        • Locale("es", "ES"): result MyResources_es_ES.class, parent MyResources.class
        The file MyResources_fr_CH.properties is never used because it is hidden by MyResources_fr_CH.class.
        Parameters:
        baseName - the name of the ResourceBundle
        locale - A locale
        classloader - a ClassLoader
        Returns:
        the desired resource bundle
        Throws:
        MissingResourceException - if the resource bundle can't be found
        NullPointerException - if any argument is null
        Since:
        1.2
      • handleGetObject

        protected abstract Object handleGetObject(String key)
        Override this method to provide the resource for a keys. This gets called by getObject. If you don't have a resource for the given key, you should return null instead throwing a MissingResourceException. You don't have to ask the parent, getObject() already does this; nor should you throw a MissingResourceException.
        Parameters:
        key - the key of the resource
        Returns:
        the resource for the key, or null if not in bundle
        Throws:
        NullPointerException - if key is null
      • getKeys

        public abstract Enumeration getKeys()
        This method should return all keys for which a resource exists; you should include the enumeration of any parent's keys, after filtering out duplicates.
        Returns:
        an enumeration of the keys