Hibernate/JPA : EmbeddedId helpers

[Craig Taylor]

I've got a class with a composite primary key (I know, I know) ... in attempting to migrate away from hibernate xml I've had to implement a Primary key class and then add the appropriate

@EmbeddedId
public MyPrimaryKeyPK getPrimaryKey( ... )

I've also added "helper" transient functions to allow existing code to use the fields of the primary key :

@Transient
public Integer getField() { return m_primarykey.getField(); }

however when running dao tests I'm getting an error claiming that the Field is not present within the model class : ( org.hibernate.QueryException: could not resolve property ).

I'm able to get it to work by removing @Transient and adding @Column( name="...", insertable=false, updateable=false ) which to me seems counter-intuitive and probably not the preferred way.

[Craig Taylor]

Just as a followup as to how I figured it out:

I ended up using @IdClass to define the id class and then marked the individual getters with @Id as appropriate.