Hibernate

Uni-directional One to One Relationship

@Entity
@Table(name = "FOO")
public class Foo {
private UUID fooId;
@OneToOne private Bar bar;
}

@Entity
@Table(name = "BAR")
public class Bar {
private UUID barId;
// No corresponding mapping to Foo.class
}

Specifies a one-way relationship between one Foo object to one Bar object.
The Foo objects are stored as rows in a table called FOO. The Bar objects are stored as rows in a table called BAR.

Notice that there is no mapping of Bar objects back to Foo objects. Bar objects can be manipulated freely without affecting Foo objects.