Question

I’m struggling to successfully implement a OneToOne mapping on my play framework application.

examples I have are:

@Entity
  public class Profile extends GenericModel {
  @Id
  @GeneratedValue(generator = "foreignGenerator")
  @GenericGenerator(name = "foreignGenerator", strategy = "foreign", 
            parameters = @Parameter(name = "property", value = "user"))
  public static int id;

  @OneToOne(mappedBy="profile",  cascade = {CascadeType.ALL})
  public static User user;
}

and :

@Entity
  public class User extends Model {

  @Required
  public String firstName;

  @Required
  public String surname;
 }

in this setup it throws:

org.hibernate.AnnotationException: No identifier specified for entity: models.Profile

EDIT: As per Christian Boariu’s answer, I have modified Profile to what you have suggested and User to:

    @Entity
  public class User extends GenericModel {

@Id
@GeneratedValue(strategy = GenerationType.AUTO)
public Long user_id;

@Required
public String firstName;

@Required
public String surname;

@OneToOne(cascade = {CascadeType.ALL})
@PrimaryKeyJoinColumn(name = "user_id", referencedColumnName = "profile_id")
public Profile profile;

public Profile getProfile() {
    return profile;
}

public void setProfile(Profile profile) {
    this.profile = profile;
}   
 }

Also added getter/setter to Profile:

public User getUser() {
    return user;
}

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

But I am now getting hibernate.id.IdentifierGenerationException: null id generated for:class models.Profile.. not sure how to correct?

Answer 1

The problem is about your Id definition.

It should not be static.

Also, user should not be static as well.

UPDATE:

So your class should be like this:

  @Entity
  public class Profile extends GenericModel {
  @Id
  @GeneratedValue(generator = "foreignGenerator")
  @GenericGenerator(name = "foreignGenerator", strategy = "foreign", 
            parameters = @Parameter(name = "property", value = "user"))
  public int id;

  @OneToOne(mappedBy="profile",  cascade = {CascadeType.ALL})
  public User user;
}