JPAContainer Addressbook Demo - Internal key

Hi:

I am modifiying the JPAContainer AddressBook Demo with MySql and I have a couple of classes (Empresa and Autor)

@Entity
public class Empresa {

    @Id
    @GeneratedValue(strategy = GenerationType.AUTO)
    private Long idEmpresa;

    @NotNull
    @Size(min = 2, max = 50)
    private String razonSocial;
    @Size(min = 2, max = 50)
    private String repLegal;
    private String direccion;
    private String ciudad;
    private String telefono;
    private String lookFeel;
    
    @OneToMany(mappedBy = "empresa")
    private Set<Autor> containerAutores; 

And Autor:

@Entity
public class Autor {

    @Id
    @GeneratedValue(strategy = GenerationType.AUTO)
    private Long idAutor;
    @NotNull
    @Size(min = 2, max = 30)
    private String autor;

In MySql we have idAutor and idEmprea as INT(11)

In attached files are the source and the output screen

how can display the value of razonSocial in Empresa in place of internal key (com.vaadin.demo.jpaaddressbook.domain.Empresa@1341b06) ?

thanks in advance