Criteria JPA - Specific attribute - jpa

Question

I need to create a criteria query that represents the follow JPQL:
I tryed to specify the class RegraContrato but no success.
SELECT G FROM Grupo G JOIN G.regras R WHERE TYPE(R) = RegraContrato AND R.numeroContrato in(123)
#Entity
#Table(name = "GRUPO_ACESSO")
public class Grupo {
#OneToMany(mappedBy = "grupo",cascade = CascadeType.ALL,fetch = FetchType.EAGER,orphanRemoval = true)
private Set<Regra> regras = Sets.newHashSet();
}
#Entity
#Table(name = "REGRA_ACESSO")
#Inheritance(strategy = InheritanceType.JOINED)
public abstract class Regra {
private static final long serialVersionUID = 5994730323053219858L;
#Id
#SequenceGenerator(name = "REGRA_ID_GENERATOR",sequenceName = "REGRA_SEQUENCE",allocationSize = 1)
#GeneratedValue(strategy = GenerationType.SEQUENCE,generator = "REGRA_ID_GENERATOR")
#Column(name = "ID")
private Long id;
}
#Entity
#PrimaryKeyJoinColumn(name = "ID")
#Table(name = "REGRA_CNPJ")
public class RegraCNPJ extends Regra {
#Column(name = "CNPJ")
private String cnpj;
}
#Entity
#PrimaryKeyJoinColumn(name = "ID")
#Table(name = "REGRA_CONTRATO")
public class RegraContrato extends Regra {
private static final long serialVersionUID = -2840125767126128182L;
#Column(name = "NUMERO_CONTRATO")
private Long numeroContrato;
}