JSF2 ApplicationScope bean instantiation time?
It seems to me, that @ApplicationScoped
beans are initiated only the first time they are accessed in a page using EL.
When I query the ApplicationMap
, will the @ApplicationScoped
bean be created?
ExternalContext ec = currentInstance.getExternalContext(); result =
ec.getApplicationMap().get(beanName);
How else could I 开发者_StackOverflowtrigger the instantiation of the application scoped bean before an XHTML page has been loaded?
You could use eager=true
in the @ManagedBean
declaration.
@ManagedBean(eager=true)
@ApplicationScoped
public class Config {
// ...
}
This way the bean will be autocreated on webapp's startup.
Instead of that, you could also use Application#evaluateExpressionGet()
to programmatically evaluate EL and so auto-create the bean if necessary. See also the example on this answer.
FacesContext context = FacesContext.getCurrentInstance();
Confic config = (Config) context.getApplication().evaluateExpressionGet(context, "#{config}", Config.class);
// ...
You could also just inject it as a @ManagedProperty
of the bean where you need it.
@ManagedBean
@RequestScoped
public class Register {
@ManagedProperty("#{config}")
private Config config;
@PostConstruct
public void init() {
// ...
}
// ...
}
JSF will auto-create it before injecting in the parent bean. It's available in all methods beyond @PostConstruct
.
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