EmbeddedId，sequence和ConstraintViolationException

Question

我有實體，它有@EmbeddedId。在id類中有幾個字段，其中一個是具有生成類型序列的Long id。當我試圖插入這個實體的實例，而沒有在embeeded id中設置id時（應該從sequence中插入），問題會出現。

org.hibernate.exception.ConstraintViolationException: Could not execute JDBC batch update 

當此embeddedId中的id設置爲任何值，則插入是成功的。

我能做些什麼來使它工作？

編輯：代碼

@Entity 
@Table(name = "TestIds") 
public class TestIds implements Serializable { 

    @EmbeddedId 
    private TestId testId; 

    public TestIds(TestId testId) { 
     this.setTestId(testId); 
    } 

    public TestId getTestId() { 
    return testId; 
    } 

    public void setTestId(TestId testId) { 
    this.testId = testId; 
    } 
} 

@Embeddable 
public class TestId implements Serializable { 

    private static final long serialVersionUID = 1L; 
    @GeneratedValue(strategy=GenerationType.AUTO, generator="my_entity_seq_gen") 
    @SequenceGenerator(name="my_entity_seq_gen", sequenceName="MY_ENTITY_SEQ") 
    @Column(name = "column_name") 
    private Long id; 

    public TestId() { 

    } 

    public Long getId() { 
     return id; 
    } 

    public void setId(Long id) { 
     this.id = id; 
    } 
} 

我執行

TestIds a = new TestIds(new TestId()); 
Session session = sessionFactory.getCurrentSession(); 

session.save(a); 
session.flush(); 

org.hibernate.exception.ConstraintViolationException: Could not execute JDBC batch update 

Caused by: 
java.sql.BatchUpdateException: Batch entry 0 insert into TestIds (column_name) values (NULL) was aborted 

Answer 1

的錯誤似乎是不可能在@EmbeddedId

Answer 2

你應該註釋@GeneratedValue添加到ID，並把你所選擇的行爲。

例如編輯爲@Id

@GeneratedValue(strategy=GenerationType.AUTO, generator="my_entity_seq_gen") 
@SequenceGenerator(name="my_entity_seq_gen", sequenceName="MY_ENTITY_SEQ") 
@Column(name = "column_name") 
private Long id;