Resource Bundle Override

This example overrides the default add-blog-entry language key (English and Spanish) for Liferay DXP’s default Blogs application. After deploying this sample hook to Liferay DXP, the Blogs application’s Add Blog Entry button is modified to display Overriden Add Blog Entry. If you change Liferay DXP’s default language to Spanish, the modified language key is translated to display in that language. For example, the text changes to Añadir entrada sobreescrita.

Figure 1: The customized Blogs application displays the new `add-blog-entry` language key in English.

For reference, the Blogs application’s language keys are stored in the liferay-portal Github repo’s modules/apps/collaboration/blogs/blogs-web/src/main/resources/content folder.

What API(s) and/or code components does this sample highlight?

This sample leverages the ResourceBundleLoader API.

How does this sample leverage the API(s) and/or code component?

This sample conveys the recommended approach to override an application’s language keys file for any module that is deployed to Liferay DXP’s OSGi runtime (not applicable to Liferay DXP’s core language keys).

The steps to override applications’ language keys are

• Implement a resource bundle loader.
• Register the service.
• Provide the new language keys that will override the original ones.

The resource bundle loader is a class that should implement the interface com.liferay.portal.kernel.util.ResourceBundleLoader. Specifically, you must implement the loadResourceBundle method, which returns the loaded resource bundle:

@Override
public ResourceBundle loadResourceBundle(String languageId) {
    return _resourceBundleLoader.loadResourceBundle(languageId);
}

Then you must set the resource bundle loader to load the resource bundles as an AggregateResourceBundleLoader.

@Reference(target = "(&(bundle.symbolic.name=com.liferay.blogs.web)(!(component.name=com.liferay.blade.samples.hook.resourcebundle.ResourceBundleLoaderComponent)))")
public void setResourceBundleLoader(
    ResourceBundleLoader resourceBundleLoader) {

    _resourceBundleLoader = new AggregateResourceBundleLoader(
        new CacheResourceBundleLoader(
            new ClassResourceBundleLoader(
                "content.Language",
                ResourceBundleLoaderComponent.class.getClassLoader())),
    resourceBundleLoader);
}

The @Reference annotation targets the original Blogs module by specifying its symbolic name com.liferay.blogs.web. This sample’s own component name (i.e., com.liferay.blade.samples.hook.resourcebundle.ResourceBundleLoaderComponent) is not targeted to use this resource bundle.

Also note the required parameters to set the resource bundle loader:

• The base language file name (e.g., content.Language).
• The classloader for your resource bundle loader.
• The resource bundle loader from the method’s parameter.

The class should also register the resource bundle loader in the OSGi runtime. This is done by setting the following three properties:

• bundle.symbolic.name: The symbolic name of the target module (i.e., the module’s keys you’re overriding).
• resource.bundle.base.name: The resource bundle base name that points to your language files.
• servlet.context.name: The servlet context name of the target module.

These properties are set in your class’s @Component annotation like this:

@Component(
    immediate = true,
    property = {
        "bundle.symbolic.name=com.liferay.blogs.web",
        "resource.bundle.base.name=content.Language",
        "servlet.context.name=blogs-web"
    }
)

Lastly, the new language.properties files should be added to the folder src/content for each locale’s keys you want to override. Since this example’s goal is to only override the English and Spanish keys, the Language_en.properties and Language_es.properties are added.

This approach can be used to override any application’s language keys (i.e., language.properties files that are inside a module deployed to Liferay DXP’s OSGi runtime). If you need to override Liferay DXP’s core language keys, see the Modifying Global Language Keys tutorial.

For more information on using a resource bundle to override an application’s language keys, see the Overriding a Module’s Language Keys tutorial.

Where Is This Sample?

There are three different versions of this sample, each built with a different build tool:

• Gradle
• Liferay Workspace
• Maven