Hi All,

I can't figure why I am getting the following errors:

javax.ejb.EJBException: null; CausedByException is:
 could not deserialize
...
...
org.hibernate.type.SerializationException: could not deserialize
...
...

@Entity
@Inheritance(strategy=InheritanceType.JOINED)
@Table(name="USERS")
public abstract class User implements Serializable {
 private String userName, group;

 public User() {
 userName = new String();
 group = new String();
 }

 @Id
 @Column(name="USERNAME")
 public String getUserName() {
 return this.userName;
 }

 public void setUserName(String userName) {
 this.userName = userName;
 }

 @Column(name="GROUP")
 public String getGroup() {
 return this.group;
 }

 public void setGroup(String group) {
 this.group = group;
 }
}

public class PreferenceAction extends BaseDispatchAction {
 public ActionForward view(ActionMapping mapping,
 ActionForm form,
 HttpServletRequest request,
 HttpServletResponse response)
 throws Exception
 {
 doView(form, request);
 return mapping.findForward(IConstants.SUCCESS_KEY);
 }

 private void doView(ActionForm form, HttpServletRequest request)
 throws Exception
 {
 Preference preference = factory.getApplicationBean().getPreference((User)getUser());
 ...
 ...
 }
}

@Entity
@Table(name="PREFERENCES")
public class Preference implements Serializable {
 private User user;
 private String first, ...;

 public Preference() {
 user = null;
 first = new String();
 ...
 ...
 }

 @Id
 @OneToOne
 @JoinColumn(name="USERNAME")
 public User getUser() {
 return this.user;
 }

 public void setUser(User user) {
 this.user = user;
 }

 @Column(name="FIRST")
 public String getFirst() {
 return this.first;
 }

 public void setFirst(String first) {
 this.first = first;
 }

 ...
 ...
}

@Stateless
public class ApplicationBean implements Application {
 @PersistenceContext(unitName="db")
 EntityManager em;

 public Preference getPreference(User user) {
 return (Preference) em.createQuery("from Preference p where p.user = :user")
 .setParameter ("user", user)
 .getSingleResult();
 }
}