Seam + Hibernate + MVC

[melampo]

Hi.

First of all, sorry for my english :D

I am newby using seam and I am trying to develope a web application with a MVC layer model (I have no choose, I didn't design the application).

I am some confused about what annotations a need for each layer and I can't find any example that implements this model. Anyone can help me?:

Entity:

@Entity
@Name("libro")
@Scope(CONVERSATION)
@Table(name = "libros")
public class Libro implements Serializable {

 private static final long serialVersionUID = -1252025299985845136L;

 private String isbn;

 private String titulo;

 private String autor;

 @Id
 @Column(name = "isbn")
 public String getIsbn() {
 return isbn;
 }

 public void setIsbn(String isbn) {
 this.isbn = isbn;
 }

 @NotNull
 @Column(name = "titulo")
 public String getTitulo() {
 return titulo;
 }

 public void setTitulo(String titulo) {
 this.titulo = titulo;
 }

 @NotNull
 @Column(name = "autor")
 public String getAutor() {
 return autor;
 }

 public void setAutor(String autor) {
 this.autor = autor;
 }
}

Service Interface:

@Local
public interface LibroManager {
 ...
 public void add();
 ...
}

Service Implementation:

@Stateful
@Name("libroManager")
@Scope(CONVERSATION)
public class LibroManagerAction implements LibroManager, Serializable {

 private static final long serialVersionUID = 4607492839166551543L;

 @In(required = false)
 @Out(required = false)
 private Libro libro;

 private LibroDAOhbn libroDAO = new LibroDAOhbn();

 ...
 public void add() {
 libroDAO.Create(libro);
 }
 ...
}

Dao Interface:

@Local
public interface LibroDAO {
 public void Create(Libro libro);

}

Dao Implementation:

@Stateless
@Name("libroDAO")

public class LibroDAOhbn implements LibroDAO {

 @PersistenceContext
 private EntityManager em;

 public void Create(Libro libro) {
 System.out.println("Registrando " + libro.getTitulo());

 try {
 em.persist(libro);
 } catch (Exception e) {
 System.out.println(e.getMessage());
 }
 }

}

Ok, when the Create(libro) method is called, I only get an exception: NULL. I think that this is caused because I lost the EntityManager or Entity context, but I don't know how to mend it.

I try to inject the libroDAOhbn in the service class with:

@In (create=true)
private LibroDAOhbn libroDAO = new LibroDAOhbn();

but I get an error everytime I call any service's method. I think that it must to have an easy solution, but I can't find it :). Some suggestions?

If I don't use a DAO layer and I do all the implementation in the service/controller , I have no problems. This runs perfectly:

@Stateful
@Name("libroManager")
@Scope(CONVERSATION)
public class LibroManagerAction implements LibroManager, Serializable {

 private static final long serialVersionUID = 4607492839166551543L;

 @In(required = false)
 @Out(required = false)
 private Libro libro;

 private LibroDAOhbn libroDAO = new LibroDAOhbn();

 ...
 public void add() {

 try {
 em.persist(libro);

 FacesMessages.instance().add( "Insertado correctamente: " + libro.getTitulo());

 } catch (Exception e) {
 System.out.println("Exception: " + e.getMessage());
 }
 ....
 }

but I need the DAO's :(

Thank's for all.

PS: Sorry for my englis again.

[melampo]

Hi again!

Following this topic: http://jboss.com/index.html?module=bb&op=viewtopic&t=70020 I understand that I am in the correct way (#6 post), but that solution seem not to work for me.

If I try with:

@In
private LibroDAOhbn libroDAO;

in my service class, it returns the following exception:

Caused by: java.lang.IllegalArgumentException: could not set field value: libroManager.libroDAO

I have just install de CVS version (Seam 1.1.0.BETA2) but the same problem continue...

Thanks.

[gavin.king]

Absolutely nothing to do with that other thread. You are trying to inject the bean class type, which of course you cannot. You must use the local interface.

@In
private LibroDAO libroDAO;

[melampo]

Ok.

Now it runs perfectly. Thank you very much.