实体映射的JPA注释

Question

我有两个实体User和Contact。用户对象包含联系人。我如何使用JPA注释 所以当我保存User对象时，联系表应该将Users的id作为其primaryKey？

            Public class User{
            public String username;
            public long id;
            public Contact contact;

            }

            public class Contact {
            public long id;
            public string phone;
            public string email;
            }

Answer 1

与此类似的东西

@Entity  
public class User{
    @Column
    public String username;
    @Id
    public long id;
    @OneToMany(mappedBy="id")
    public Contact contact;

}

@Entity 
public class Contact {
    @Id
    public long id;
    @Column
    public string phone;
    @Column
    public string email;
}