package org.krams.domain; import javax.persistence.Entity; import javax.persistence.GeneratedValue; import javax.persistence.GenerationType; import javax.persistence.Id; import javax.persistence.OneToOne; import org.codehaus.jackson.annotate.JsonBackReference; @Entity(name="role") public class Role { @Id @GeneratedValue(strategy = GenerationType.AUTO) private Long id; @JsonBackReference @OneToOne private User user; private Integer role; public Role() {} ...getters/setters }