我在设置一些实体的JPA映射时遇到了麻烦。我定义了一个父实体,如下所示。
@Entity
@Table(name="EIF_INSTANCE_HDR")
public class InstanceEntity implements Serializable{
private static final long serialVersionUID = 1L;
@Id
@GeneratedValue(generator="eif_inst_gen")
@SequenceGenerator(name="eif_inst_gen",sequenceName="EIF_INSTANCE_SEQ")
@Column(name = "EAIH_ID")
private Long eaihid;
@Column(name = "EAD_ID")
private Long eadid;
@OneToMany(targetEntity=InstanceNotifyEntity.class, mappedBy="instance",fetch=FetchType.EAGER, cascade = CascadeType.ALL)
private List<InstanceNotifyEntity> userDetails = new ArrayList<InstanceNotifyEntity>();
}
我有一个具有复合键的子实体,并且具有对此表的主键的外键,如下所示:
@Entity
@Table(name="EIF_INST_NOTIFIED")
public class InstanceNotifyEntity implements Serializable{
private static final long serialVersionUID = 1L;
@Id
@ManyToOne
@JoinColumn(name="EAIH_ID", referencedColumnName="EAIH_ID")
private InstanceEntity instance;
@Id
@Column(name="USER_ID")
private Long userId;
@Column(name="COMMENT_TXT")
private String commentText;
}
我知道子实体是错误的,但我不确定如何设置它以拥有一个复合主键。我知道需要设置一个主键类,但当一个字段是指向父类的外键时,我不知道该如何做。一旦设置好了,父类如何引用子实体?