[英]Java JPA - OneToOne Relation between Entities not working
Licitatie Entity: 合法实体:
@Entity
@Table(name="licitatie")
public class Licitatie implements Serializable {
...
//bi-directional one-to-one association to Licitatie
@OneToOne(mappedBy="licitatie")
private Produs produs;
...
}
Produs Entity: 产品实体:
@Entity
@Table(name="produs")
//@DiscriminatorColumn(name="id", discriminatorType=DiscriminatorType.INTEGER)
@MappedSuperclass
public class Produs implements Serializable {
...
//bi-directional one-to-one association to Produs
@OneToOne
@JoinColumn(name="licitatie_id")
private Licitatie licitatie;
...
}
Database: 数据库:
Licitatie: 合法:
id start status
1 5 open
2 5 open
3 5 open
Produs: 产品:
id licitatie_id DTYPE description
1 1 Carte ...
2 2 Carte ...
3 3 Carte ...
After I run tris query: "SELECT t FROM Licitatie t" , the attribute Product from object of type Licitatie is null. 在我运行tris查询后: “ SELECT t FROM Licitatie t” ,类型为Licitatie的对象的Product属性为null。 But there are records in tables.
但是表中有记录。
What I'm doing wrong? 我做错了什么?
* EDIT * *编辑*
After I get data from table, calling getProdus() return this message: 从表中获取数据后,调用getProdus()返回此消息:
{IndirectSet: not instantiated} {IndirectSet:未实例化}
SOLVED 解决了
I've added column PRODUS_ID to licitatie table. 我已将列PRODUS_ID添加到许可证表中。
Licitatie: id produs_id ... Produs: id, licitatie_id ... 合法:id produs_id ...产品:id,licitatie_id ...
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