jsf - Read resource bundle properties in a managed bean

Question

Using <resource-bundle> files I'm able to have i18n text in my JSF pages.

But is it possible to access these same properties in my managed bean so I can set faces messages with i18n values?

Answer 1

Assuming that you've configured it as follows:

<resource-bundle>
    <base-name>com.example.i18n.text</base-name>
    <var>text</var>
</resource-bundle>

If your bean is request scoped, you can just inject the <resource-bundle> as @ManagedProperty by its <var>:

@ManagedProperty("#{text}")
private ResourceBundle text;

public void someAction() {
    String someKey = text.getString("some.key");
    // ... 
}

Or if you just need some specific key:

@ManagedProperty("#{text['some.key']}")
private String someKey;

public void someAction() {
    // ... 
}

---

If your bean is however in a broader scope, then evaluate #{text} programmatically in method local scope:

public void someAction() {
    FacesContext context = FacesContext.getCurrentInstance();
    ResourceBundle text = context.getApplication().evaluateExpressionGet(context, "#{text}", ResourceBundle.class);
    String someKey = text.getString("some.key");
    // ... 
}

Or if you only need some specific key:

public void someAction() {
    FacesContext context = FacesContext.getCurrentInstance();
    String someKey = context.getApplication().evaluateExpressionGet(context, "#{text['some.key']}", String.class);
    // ... 
}

---

You can even just get it by the standard ResourceBundle API the same way as JSF itself is already doing under the covers, you'd only need to repeat the base name in code:

public void someAction() {
    FacesContext context = FacesContext.getCurrentInstance();
    ResourceBundle text = ResourceBundle.getBundle("com.example.i18n.text", context.getViewRoot().getLocale());
    String someKey = text.getString("some.key");
    // ... 
}

---

Or if you're managing beans by CDI instead of JSF, then you can create a @Producer for that:

public class BundleProducer {

    @Produces
    public PropertyResourceBundle getBundle() {
        FacesContext context = FacesContext.getCurrentInstance();
        return context.getApplication().evaluateExpressionGet(context, "#{text}", PropertyResourceBundle.class);
    }

}

And inject it as below:

@Inject
private PropertyResourceBundle text;

---

Alternatively, if you're using the Messages class of the JSF utility library OmniFaces, then you can just set its resolver once to let all Message methods utilize the bundle.

Messages.setResolver(new Messages.Resolver() {
    public String getMessage(String message, Object... params) {
        ResourceBundle bundle = ResourceBundle.getBundle("com.example.i18n.text", Faces.getLocale());
        if (bundle.containsKey(message)) {
            message = bundle.getString(message);
        }
        return MessageFormat.format(message, params);
    }
});

See also the example in the javadoc and the showcase page.