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Tags Converters, EL, JSF, Tip, Tutorial, Validators
This post here discusses using an EL reference to specify a converter. This gets around the fact that you cannot use CDI beans in a converter class.
You can also do this in a validator, for example using the validator attribute on h:inputText. This is useful if you need access to other instance variables in order to do the validation. In my case, I needed access to a list for a table to verify uniqueness on string names in the list.
This is mentioned in Core JSF 3 on page 294:-
In the preceding section, you saw how to implement a validation class. However, you can also add the validation method to an existing class and invoke it through a method expression, like this:
<h:inputText id=”card” value=”#{payment.card}”
required=”true” validator=”#{payment.luhnCheck}”/>
The payment bean must then have a method with the exact same signature as the validate method of the Validator interface:public class PaymentBean {
…
public void luhnCheck(FacesContext context, UIComponent component, Object value) {
… // same code as in the preceding example
}
}Why would you want to do this? There is one major advantage. The validation method can access other instance variables of the class. You saw an example in the section, “Supplying Attributes to Converters” on page 289.