0

在 OneToMany 关系中保留一个实体及其子实体时遇到问题。这是我的两个实体：

@Entity
@Table(name="USER")
public class User implements Serializable {
  ...
  @Id
  @Column(name="ID_USER")
  private String idUser;

  @OneToMany(mappedBy="user", cascade=CascadeType.PERSIST)
  private List<Address> address;

  public List<Address> getAddress() {
     return this.address;
  }

  public void setAddress(List<Address> address) {
     this.address = address;
  }

  public Address addAddress(Address address) {
     getAddress().add(address);
     address.setUser(this);

     return address;
  }

  public Address removeAddress(Address address) {
     getAddress().remove(address);
     address.setUser(null);

     return address;
  }
  ...
}

@Entity
@Table(name="ADDRESS")
public class Address implements Serializable {
    ...


   @EmbeddedId
   private AddressPK id;

    @ManyToOne(cascade = CascadeType.PERSIST)
    @JoinColumn(name="ID_USER", insertable=false, updatable=false, nullable=false)
    private User user;

    public User getUser() {
        return this.user;
    }

    public void setUser(User user) {
        this.user = user;
    }
}

@Embeddable
public class AddressPK implements Serializable {
   ...
   @Column(name="ID_USER", insertable=false, updatable=false)
   private String idUser;
   ...
}

现在生成 ORA-02291 错误的持久操作：

User u = new User();
u.setAddress(new ArrayList<Address>());

u.set...

Address a1 = new Address();
a1.set...
u.addAddress(a1);

Address a2 = new Address();
a2.set...
u.addAddress(a2);

entityManager.persist(u);

任何想法来解决这个问题？

谢谢大家！

4

2 回答 2

0

我认为您需要在地址表中删除@JoinColumn 的名称属性

@Entity
@Table(name="ADDRESS")
public class Address implements Serializable {
...
@ManyToOne(cascade = CascadeType.PERSIST)
@JoinColumn(insertable=false, updatable=false)
private User user;

public User getUser() {
    return this.user;
}

public void setUser(User user) {
    this.user = user;
}

}

您已经从用户端获得了 mappedBy="user" 。

于 2015-08-20T09:21:48.377 回答
0

从昨天开始我就陷入了困境，但现在我找到了解决问题的方法。在我的情况下，错误是由于我有 TRIGGERS 将 MY_SEQUENCE.nextval 设置为其各自实体的表的 PK。

然后，更改 TRIGGER 以验证来自实体的 :new.PK 是否为空的解决方案来设置它。相反，如果它不为空，则可以理解为 SEQUENCE 是从 JPA 设置为 PK 的。例如：

create or replace TRIGGER "MYSCHEMA"."TGR_MYTABLE_INSERT"
  before insert on MYTABLE
  for each row
  begin
  if :new.PK_MYTABLE is null then
    select SEQ_MYTABLE.nextval
    into :new.PK_MYTABLE
    from dual;
  end if;
  end;
于 2016-10-20T14:27:09.983 回答