Why initialize id when is inherited from super class in JPA Hibernate

I have this super-class

open class Base(
    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY) var id: Long = 0,
    @Column var userId: Long? = 0,
    @Column var created: Date = Date(),
    @Column var updated: Date = Date(),
    @Column var currency: String = ""
)

which I then inherit in the following class

@Entity
@Table(name = "foo")
class Foo(
    @Column var name: String = "",
) : Base()

Now the compiler complains

Persistent entity ‘Foo’ should have primary key

But the id is defined in Base. Why is it complaining?

>Solution :

But the id is defined in Base. Why is it complaining?

Possibly because Foo does not appear to inherit from Base. But even if it did inherit from Base, annotations on the superclass and its members are of interest to JPA only if the superclass is a @MappedSuperclass or an @Entity itself.