Question

Is it possibile to map two differents discriminator values to the same concrete java class?

Something like this:

@DiscriminatorValue("4")
@DiscriminatorValue("5")
public class CartaImpl extends RapportoImpl implements Carta, Cloneable {

Another question: is it possible to have a default implementation when no class is provided for an indicator field value for not raising this exception?

Missing class for indicator field value 

Answer 1

Makes no sense. If instances of that class have two possible values of the discriminator in the DB then create two different classes in the same inheritance tree, one per value of the discriminator