@IdClass with @Ids pointing to non-primitive @ManyToOne

unrealdummy · **Joined:** Sat Feb 07, 2009 12:31 am **Posts:** 21

Hi,

I'm trying to use @IdClass as composite key. But a lot of example used @IdClass pointing to a class with simple entities. Consider the following:

Code:

@Entity
@IdClass(AssignedRoleId.class)
public class AssignedRole
{
  @Id
  @ManyToOne
  private User userId;
  
  @Id
  @ManyToOne  
  private Role roleId;

  private Date dateAssigned;
}

public class AssignedRoleId
{
  private long userId;
  private long roleId;
}

other entities:
user ( id, username, password )
role (id, role, description )

This quite work but only one foreign key is generated (AssignedRole.userId), there's no generated foreign key for AssignedRole.role.

I can't use user and role as data type for members of AssignedRoleId because hibernate will generate tinyblob as the type of the column if I do.

Notice the name of members of AssignedRole, they're "userId" and "roleId" instead of "user" and "role", because I want those keys stored in the table AssignedRole as "userId" and "roleId". Even if you annotate it with @JoinColumn it will just get ignored. And by looking at the generated sql from "select as.user from AssignedRole as" it only returns a long value instead of an object, so an exception throws when you try "select as.user.username from AssignedRole as" because "as.user" is just a long value and not a user object.

Is the semantics that I want supported by hibernate? Or using @IdClass with @Id(s) with @ManyToOne is misusing hibernate?

Or, can I use non-primitive type as members of AssignedRoleId without letting hibernate generate a blob as the datatype of the column?

Thanks.