Question

I have the following 2 entities:

   @Entity(name = "Employee")
   @Table(name = "EMPLOYEE")
   public class Employee implements Serializable {
      @Id
      @Column(name = "EMP_ID", insertable = true, updatable = false, nullable = false)
      private int id;

以及

@Entity(name = "Draw")
@Table(name = "DRAW")

public class Draw extends AuditableEntity {
    @Id
    @OneToOne(fetch = FetchType.LAZY, cascade = {CascadeType.PERSIST, CascadeType.MERGE})
    @JoinColumn(name = "EMP_ID", referencedColumnName = "EMP_ID")
    @Cascade({org.hibernate.annotations.CascadeType.SAVE_UPDATE,
        org.hibernate.annotations.CascadeType.MERGE})
    private Employee employee = null;

只想说,他们想要模仿它的方式。这是一种特有的“一对一”关系。然而,在我接受测试时,我有以下错误:

nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name sessionFactory defined in class path resource [META-INF/spring/datasource-context.xml]: Invocation of init method failed; nested exception is org.hibernate.MappingException: composite-id class must implement Serializable: com.myprojects.tet.data.entity.Draw

Why is the employee key in Draw interpreted as a composite-id? Also how do I fix this error. I have read that the entity referenced has to be serializable but also that it needs to implement method equals 以及 hashCode (which I haven t implemented yet). Should implementation of those two fix that error?

www.un.org/Depts/DGACM/index_spanish.htm 清晰度:

I have two modeled tables: EMPLOYEE 以及 DRAW:

。

The draw table will be populated 以及 purged every certain time, so column totalPoint cannot be in table EMPLOYEE. I am unsure if my entity relations are correct (i.e. having entity employee as the id for draw).

Answer 1

rel=“nofollow”>@PrimaryKeyJoinColumn ::

@Id
@Column(name = "EMP_ID")
private int id;

@OneToOne(fetch = FetchType.LAZY, cascade = {CascadeType.PERSIST, CascadeType.MERGE})
@PrimaryKeyJoinColumn(name = "EMP_ID", referencedColumnName = "EMP_ID")
@Cascade({org.hibernate.annotations.CascadeType.SAVE_UPDATE, org.hibernate.annotations.CascadeType.MERGE})
private Employee employee;

友情链接