Hibernate@embedable行为辅助表
我有一个非常简单的项目,包含3个类:Hibernate@embedable行为辅助表,hibernate,hibernate-mapping,Hibernate,Hibernate Mapping,我有一个非常简单的项目,包含3个类: @Entity @Table(name = "A", uniqueConstraints = {}) @org.hibernate.annotations.Table(appliesTo = "A", indexes = {}) @SecondaryTable(name = "C", pkJoinColumns {@PrimaryKeyJoinColumn(columnDefinition = "A_ID", name = "A_ID")}) public
@Entity
@Table(name = "A", uniqueConstraints = {})
@org.hibernate.annotations.Table(appliesTo = "A", indexes = {})
@SecondaryTable(name = "C", pkJoinColumns {@PrimaryKeyJoinColumn(columnDefinition = "A_ID", name = "A_ID")})
public class Machine
{
@Id
@GeneratedValue
@Column(name = "A_ID", nullable = false)
private Integer id;
@Column(name = "a1", nullable = false)
private Integer a1;
@Column(name = "c1", table = "C", nullable = false)
private Integer c1;
@ManyToMany(fetch = FetchType.LAZY)
@JoinTable(name = "A_B", joinColumns = {@JoinColumn(name = "A_ID")}, inverseJoinColumns = {@JoinColumn(name = "B_ID")})
private List<B> bs = new ArrayList<B>();
}
@Entity
@Table(name = "B")
@SecondaryTable(name = "A_B", pkJoinColumns = {@PrimaryKeyJoinColumn(columnDefinition = "B_ID", name = "B_ID")})
@org.hibernate.annotations.Table(appliesTo = "B")
public class B {
@Id
@GeneratedValue
@Column(name = "B_ID", nullable = false)
private Integer id;
@Column(name = "B_1", nullable = false)
private Integer b1;
@Embedded
@AttributeOverrides({
@AttributeOverride(name = "d1", column = @Column(name = "D_1", table = "A_B")),
@AttributeOverride(name = "d2", column = @Column(name = "D_2", table = "datastore_assignment"))})
private final D d = new D();
}
@Embeddable
public class D
{
private long d1;
private long d2;
}
但问题是:
A_B table
A_ID B_ID D_1 D_2
1 1 0 0
1 2 0 0
1 NULL 1 1
1 NULL 1 1
有什么想法吗
谢谢大家!
问候
问题是A不知道D_1和D_2,也不插入它们。hibernate并不关心链接表和辅助表是否相同,而是在保存B时将D_1/D_2插入其中。要解决此问题,请执行以下操作: 添加反向,告诉A它不应该插入A_B,因为它不知道D_1和D_2
@ManyToMany(fetch = FetchType.LAZY, mappedBy = ...)
@JoinTable(name = "A_B", joinColumns = {@JoinColumn(name = "A_ID")}, inverseJoinColumns = {@JoinColumn(name = "B_ID")})
private List<B> bs = new ArrayList<B>();
一定要做好准备
a.getBs().Add(b);
b.setA(a);
什么包是@Inverse?谢谢,对不起,在JPA中,我想是mappedby
@ManyToOne(name = "B_1", nullable = false, table = "A_B")
private A a;
a.getBs().Add(b);
b.setA(a);