java - 找到同一集合异常的两种表示形式？

Question

你好，我有以下代码:

@Entity
public class VirtualMeasure extends AbstractMeasure implements Record {

@OneToMany(fetch = FetchType.LAZY, cascade = {CascadeType.REMOVE}, mappedBy 
= "virtualMeasureMyActionId.virtualMeasure")
@Access(AccessType.FIELD)
private Set<VirtualMeasureMyAction> vmMyAction;
}

@Entity
@AssociationOverrides({
    @AssociationOverride(name = "virtualMeasureMyActionId.virtualMeasure",         
joinColumns = @JoinColumn(name = "virtualMeasureId")),
    @AssociationOverride(name = "virtualMeasureMyActionId.myAction", 
joinColumns = @JoinColumn(name = "myActionId")) })
public class VirtualMeasureMyAction implements Record {

/**
 * virtualMeasureViewId : VirtualMeasureViewId
 */
@EmbeddedId
private VirtualMeasureMyActionId virtualMeasureMyActionId;
}


@Embeddable
public class VirtualMeasureMyActionId implements Record {

@ManyToOne(fetch=FetchType.LAZY)
private VirtualMeasure virtualMeasure;


@ManyToOne(fetch=FetchType.LAZY)
private MyAction myAction;
}

在我运行的地方出现此错误[create]:javax.persistence.PersistenceException:org.hibernate.HibernateException:找到同一集合的两个表示:vmMyAction

Answer 1

问题是，当您坚持时， hibernate session 会检测到您在同一个 session 中两次拥有相同的集合。

注意不要在实体中重复 setter 和 getter，并使用 merge() 而不是 update()。