xref: /trunk/main/offapi/com/sun/star/resource/XResourceBundle.idl (revision ffd38472365e95f6a578737bc9a5eb0fac624a86)

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#ifndef __com_sun_star_resource_XResourceBundle_idl__
#define __com_sun_star_resource_XResourceBundle_idl__

#ifndef __com_sun_star_container_XNameAccess_idl__
#include <com/sun/star/container/XNameAccess.idl>
#endif

#ifndef __com_sun_star_lang_Locale_idl__
#include <com/sun/star/lang/Locale.idl>
#endif


//=============================================================================

module com { module sun { module star { module resource {

//=============================================================================
/** Resource bundles contain locale-specific objects.

    <p>When your program needs a locale-specific resource, such as
    <code>String</code> 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, which isolates most, if not all, of the
    locale-specific information in resource bundles.

    <p>This allows you to write programs that can:

    <UL type=SQUARE>

    <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> One resource bundle is, conceptually, a set of related services
    that supports <code>XResourceBundle</code>. Each related service of
    <code>XResourceBundle</code> has the same base name plus an
    additional component that identifies its locale. For example, suppose
    your resource bundle is named <code>MyResources</code>. The first
    service you are likely to implement is the default resource bundle,
    which has the same name as its family--<code>MyResources</code>. You
    can also provide as many related locale-specific services as you need.

    For example, perhaps you would provide a German one named
    <code>MyResources_de</code>.

    <P>
    Each related implementation of <code>XResourceBundle</code> contains
    the same items, but the items have been translated for the locale
    represented by that <code>XResourceBundle</code> implementation. For
    example, both <code>MyResources</code> and <code>MyResources_de</code>
    may have a <code>String</code> that is used on a button for
    confirming operations. In <code>MyResources</code> the
    <code>String</code> may contain <code>OK</code> and in
    <code>MyResources_de</code> it may contain <code>Gut</code>.

    <P>
    If there are different resources for different countries, you
    can make specializations: for example, <code>MyResources_de_CH</code>
    is the German language (de) in Switzerland (CH). If you only want to
    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>XResourceBundle</code> implementation using the
    <type>XResourceBundleLoader</type> service:

    <listing>
    XResourceBundle myResources = xLoader.getBundle("MyResources", currentLocale);
    </listing>

    <p>The first argument specifies the family name of the resource
    bundle that contains the object in question. The second argument
    indicates the desired locale. <code>getBundle</code> uses these two
    arguments to construct the name of the <code>ResourceBundle</code>
    subclass it should load according to the following specifications.

    <P>The resource bundle lookup searches for services with various
    suffixes on the basis of (1) the desired locale and (2) the current
    default locale as returned by Locale.getDefault(), and (3) the root
    resource bundle (baseclass), in the following order from lower-level
    (more specific) to parent-level (less specific):
    <p> baseclass + "_" + language1 + "_" + country1 + "_" + variant1
    <BR> baseclass + "_" + language1 + "_" + country1
    <BR> baseclass + "_" + language1
    <BR> baseclass + "_" + language2 + "_" + country2 + "_" + variant2
    <BR> baseclass + "_" + language2 + "_" + country2
    <BR> baseclass + "_" + language2
    <BR> baseclass

    <P> For example, if the current default locale is <TT>en_US</TT>, the
    locale that the caller is interested in is <TT>fr_CH</TT>, and the
    resource bundle name is <TT>MyResources</TT>; resource bundle lookup
    will search for the following services, in order:
    <BR> <TT>MyResources_fr_CH
    <BR> MyResources_fr
    <BR> MyResources_en_US
    <BR> MyResources_en
    <BR> MyResources</TT>

    <P> The result of the lookup is a service, but that service may be
    backed by a property file on disk. If a lookup fails,
    <code>getBundle()</code> throws a
    <code>MissingResourceException</code>.

    <P> The base service <strong>must</strong> be fully qualified (for
    example, <code>myPackage::MyResources</code>, not just
    <code>MyResources</code>).

    <P> Resource bundles contain key/value pairs. The keys uniquely
    identify a locale-specific object in the bundle. Here is an
    example of a <code>XResourceBundle</code> implementation that contains
    two key/value pairs:

    <listing>
    class MyResource extends com.sun.star.resource.XResourceBundle
    {
        // some queryInterface stuff
        // ...
        public final Object getDirectElement(String key)
        {
            if (key.equals("okKey")) return "Ok";
            if (key.equals("cancelKey")) return "Cancel";
            return null;
        }
    }
    </listing>

    <p>Keys are always <code>String</code>s. In this example, the keys
    are <code>OkKey</code> and <code>CancelKey</code>. In the above
    example, the values are also <code>String</code>s--<code>OK</code>
    and <code>Cancel</code>--but they do not have to be. The values can
    be any type of object.

    <P> You retrieve an object from resource bundle using the appropriate
    get method. Because <code>OkKey</code> and <code>CancelKey</code>
    are both strings, you use <code>getByName</code> to retrieve them:

    <listing>
    button1 = new Button(myResourceBundle.getByName("OkKey").getString());
    button2 = new Button(myResourceBundle.getByName("CancelKey").getString());
    </listing>

    <p>The get methods all require the key as an argument and return
    the object if found. If the object is not found, the get methods
    throw a <type scope="com::sun::star::container">NoSuchElementException</type>.

    <P> <STRONG>NOTE:</STRONG> You should always supply a base service
    with no suffixes. This will be the class of "last resort" if a
    locale is requested that does not exist. In fact, you must provide
    <I>all</I> of the services in any given inheritance chain for which
    you provide a resource.  For example, if you provide
    <TT>MyResources_fr_BE</TT>, you must provide <I>both</I>
    <TT>MyResources</TT> <I>and</I> <TT>MyResources_fr</TT>, or the
    resource bundle lookup will not work right.

    <P>You do not have to restrict yourself to using a single family of
    <code>ResourceBundle</code>s. For example, you could have a set of
    bundles for exception messages, <code>ExceptionResources</code>
    (<code>ExceptionResources_fr</code>, <code>ExceptionResources_de</code>, ...),
    and one for widgets, <code>WidgetResource</code> (<code>WidgetResources_fr</code>,
    <code>WidgetResources_de</code>, ...); breaking up the resources however you like.

    @see        MissingResourceException
    @see         Locale
    @version     0.1 26 May 1999
    @author      Mark Davis
    @author      Markus Meyer
    @deprecated draft
*/
published interface XResourceBundle: com::sun::star::container::XNameAccess
{
    //-------------------------------------------------------------------------
    /** contains the parent bundle of this bundle.

        <p>The parent bundle is searched by the method
        <method scope="com::sun::star::container">XNameAccess::getByName</method>
        when this bundle does not contain a particular resource.
     */
    [attribute] XResourceBundle Parent;

    //-------------------------------------------------------------------------
    /** @returns
        the locale for this resource bundle.

        <p>This function can be used to determine whether the
        resource bundle that is returned really corresponds to the
        requested locale or is a fallback.

    */
    com::sun::star::lang::Locale getLocale();

    //-------------------------------------------------------------------------
    /** @returns
        an object from a resource bundle or NULL if no resource
        exists.

        <p>It does not look in the parents.

        @param key
            specifies the element.
    */
    any getDirectElement( [in] string key );

};

//=============================================================================

}; }; }; };

#endif