CDI Injection into a FacesConverter
From just a few searches, this seems like a problem that has been around for a while. I have written a FacesConverter that looks like the following. The object Category is a JPA entity and CategoryControl is the DAO that fetches it.
@FacesConver开发者_如何学运维ter(value = "categoryConverter")
public class CategoryConverter implements Converter {
@Inject private CategoryControl cc;
public CategoryConverter() { }
@Override
public Object getAsObject(FacesContext context, UIComponent component, String value) {
if (cc != null) return cc.getByName(value);
System.out.println("CategoryConverter().getAsObject(): no injection!");
return null;
}
@Override
public String getAsString(FacesContext context, UIComponent component, Object value) {
if (!(value instanceof Category)) return null;
return ((Category) value).getName();
}
}
As you probably guessed by now, I never get the injection. I got this workaround from this page, which looks like this.:
Workaround for this problem: create this method in your localeController:
public Converter getConverter()
{
return FacesContext.getCurrentInstance().getApplication().createConverter("localeConverter");
}
and use converter="#{localeController.converter}" in your h:selectOneMenu.
However I can't make this work either. My backing bean creates and returns a converter all right, but it doesn't get the object injected into it.
I am using MyFaces CODI 1.0.1. With the current GlassFish/Weld container. Can anyone suggest a solution before I re-code to not use a Converter?
Replace
@FacesConverter(value = "categoryConverter")
by
@Named
and use
<h:inputSomething converter="#{categoryConverter}" />
or
<f:converter binding="#{categoryConverter}" />
instead of
<h:inputSomething converter="categoryConverter" />
or
<f:converter converterId="categoryConverter" />
By the way, similar problem exist for @EJB
inside a @FacesConverter
. It however offers a way to be grabbed by JNDI manually. See also Communication in JSF 2.0 - Getting an EJB in @FacesConverter and @FacesValidator. This way you can use a @FacesConverter(forClass=Category.class)
without manually defining it everytime. Unfortunately I can't tell from top of head how to realize that for CDI beans.
Update: if you happen to use JSF utility library OmniFaces, since version 1.6 is adds transparent support for using @Inject
and @EJB
in a @FacesConverter
class without any additional configuration or annotations. See also the CDI @FacesConverter
showcase example.
The @Inject
Annotation only works in CDI managed instances. If you want to use CDI features inside a non-CDI managed instance (Like a JSF Validator or a JSF Converter) you can just programm against the CDI API.
This works only in at least Java EE 7 + CDI 1.1 server.
@FacesValidator("userNameValidator")
public class UserNameValidator implements Validator {
private UserService userService;
public UserNameValidator(){
this.userService = CDI.current().select(UserService.class).get();
}
@Override
public void validate(FacesContext context, UIComponent component, Object value) throws ValidatorException {
....
}
}
https://docs.oracle.com/javaee/7/api/javax/enterprise/inject/spi/CDI.html
With all the AnnotationHell in Java EE people forget how to code.
Just use @Advanced of CODI for your @FacesConverter see the Wiki.
As soon as a converter or a validator is annotated with @Advanced it's possible to use @Inject.
Per BalusC's answer here, I decided to add JSF (requestscoped) managed beans that only contained @FacesConverter and Converter to resolve this issue in my app, since I'm migrating from JSF managed beans to CDI managed beans.
I tried CODI @Advanced against @FacesConverter, but it does not inject the bean at all.
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