How can I access messages bundle from java code to get message according to current locale?
I tried using @ManagedProperty
like below:
@Named
@SessionScoped
public class UserBean implements Serializable {
@ManagedProperty("#{msg}")
private ResourceBundle bundle;
// ...
public void setBundle(ResourceBundle bundle) {
this.bundle = bundle;
}
}
However, it remains null
. It seems that it doesn't work inside a @Named
.
This is how I registered the resource bundle in faces-context.xml
:
<application>
<message-bundle>validator.messages</message-bundle>
<locale-config>
<supported-locale>en_US</supported-locale>
<supported-locale>ua_UA</supported-locale>
</locale-config>
<resource-bundle>
<base-name>lang.messages</base-name>
<var>msg</var>
</resource-bundle>
</application>
udated by author:
@BalusC I get error
16:29:10,968 ERROR [org.apache.catalina.core.ContainerBase.[jboss.web].[default-host].[/WEBSearchPrime_JB_lang].[Faces Servlet]] (http-localhost-127.0.0.1-8080-1) Servlet.service() for servlet Faces Servlet threw exception: org.jboss.weld.exceptions.IllegalProductException: WELD-000054 Producers cannot produce non-serializable instances for injection into non-transient fields of passivating beans\\\\n\\\\nProducer\\: Producer Method [PropertyResourceBundle] with qualifiers [@Any @Default] declared as [[method] @Produces public util.BundleProducer.getBundle()]\\\\nInjection Point\\: [field] @Inject private model.UserBean.bundle
note, that I also put Serializable interface
You can't use @javax.faces.bean.ManagedProperty
in a CDI managed bean as annotated with @Named
. You can only use it in a JSF managed bean as annotated with @ManagedBean
.
You need use @javax.faces.annotation.ManagedProperty
instead, along with an @Inject
. This was introduced in JSF 2.3.
@Inject @javax.faces.annotation.ManagedProperty("#{msg}")
private ResourceBundle bundle;
Noted should be that this gets injected as a @Dependent
. So be aware that when you inject this into a @SessionScoped
bean, then it would basically become @SessionScoped
too and thus stick to the originally injected value forever. So any potential locale changes later on in the session won't be reflected there. If this is a blocker, then you should really inject it into a @RequestScoped
or @ViewScoped
only, or make use of a @Producer
as shown below.
CDI doesn't have native annotations to inject the evaluation result of an EL expression. The CDI approach is using a "CDI producer" with @Produces
wherein you return the concrete type, which is PropertyResourceBundle
in case of .properties
file based resource bundles.
So, if you cannot upgrade to JSF 2.3, then just drop this class somewhere in your WAR:
@RequestScoped
public class BundleProducer {
@Produces
public PropertyResourceBundle getBundle() {
FacesContext context = FacesContext.getCurrentInstance();
return context.getApplication().evaluateExpressionGet(context, "#{msg}", PropertyResourceBundle.class);
}
}
With this, can inject it as below:
@Inject
private PropertyResourceBundle bundle;
In addition to BalusC's answer:
Since JSF 2.3 it is also possible to inject a resource bundle defined in faces-config.xml without the use of a producer method. There is a new annotation javax.faces.annotation.ManagedProperty
(note it is in the ...annotation
package, not the ...bean
package) that works with @Inject
:
// ...
import javax.faces.annotation.ManagedProperty;
// ...
@Named
@SessionScoped
public class UserBean implements Serializable {
// ...
@Inject
@ManagedProperty("#{msg}")
private ResourceBundle bundle;
// ...
}
Perhaps I'm getting something wrong, but actually neither of the solutions provided worked for my use case. So I'm providing another answer that worked for me.
With the answer provided by BalusC I encountered the following problems:
As I'm using ajaxbased validation, my beans are @ViewScoped
, and must be serializable. As neither ResourceBundle
nor PropertyResourceBundle
are serializable they can't be injected with @Dependent
scope.
If I try to change the producer to use @RequestScoped
it also fails because ResourceBundle
is not proxyable as it defines final
methods.
As I'm using JSF 2.3 (JBoss 7.2EAP) I went with the solution provided by Jören Haag and initially it seemed to work. Like the original question, I also have multiple supported locales, and the user can change between locales (in my case ca
and es
)
The problems I faced with Jören answer are
The ResourceBundle
returned is evaluated when the bean is created. In his example he is using a @SessionScoped
bean. The ResourceBundle
will be resolved with the current locale when the session is created. If the user later changes the locale, the ResourceBundle
will not get updated. This also happens with @ViewScoped
beans if the user can change the language without changing the view.
I also encountered another issue with beans that need to preload data with a <f:viewAction>
. In this case, the bean is instantiated earlier, so the ResourceBundle
gets injected before the user locale is set with <f:view locale="#{sessionBean.locale}">
. So If the user browser is using es
, but the user changed the locale to ca
, the bundle will be loaded with es
instead, because the view locale is not set to ca
with the sessionBean.locale
until the render phase.
To overcome this issues that's the solution that worked for me for the use case of the question using injection would be:
@SessionScoped
public class UserBean implements Serializable {
@Inject
@ManagedProperty("#{msg}")
private Instance<ResourceBundle> bundle;
// ....
public void someAction() {
String message = bundle.get().getString("someLabel");
// ...
}
}
As the original question doesn't require injection, only asks how to access a resource bundle with the current locale, a solution without injection, and without the overhead of evaluating EL expression #{msg}
every time bundle.get()
is called would be:
@SessionScoped
public class UserBean implements Serializable {
@Inject
private FacesContext context;
// ...
public void someAction() {
ResourceBundle bundle = context.getApplication().getResourceBundle(context, "msg");
String message = bundle.getString("someLabel");
// ...
}
}
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