Question

我在我的项目中使用kotlin和JPA，但懒惰委托的kotlin似乎不适用于hibernate：

    @get:Transient
    private val shop:Shop by lazy { shopService.shop(shopId!!) }

我收到错误：

org.hibernate.MappingException: Could not determine type for: kotlin.Lazy, at table: order, for columns: [org.hibernate.mapping.Column(shop$delegate)]
at org.hibernate.mapping.SimpleValue.getType(SimpleValue.java:456) ~[hibernate-core-5.2.17.Final.jar:5.2.17.Final]
at org.hibernate.mapping.SimpleValue.isValid(SimpleValue.java:423) ~[hibernate-core-5.2.17.Final.jar:5.2.17.Final]
at org.hibernate.mapping.Property.isValid(Property.java:226) ~[hibernate-core-5.2.17.Final.jar:5.2.17.Final]
at org.hibernate.mapping.PersistentClass.validate(PersistentClass.java:597) ~[hibernate-core-5.2.17.Final.jar:5.2.17.Final]
at org.hibernate.mapping.RootClass.validate(RootClass.java:265) ~[hibernate-core-5.2.17.Final.jar:5.2.17.Final]
at org.hibernate.boot.internal.MetadataImpl.validate(MetadataImpl.java:329) ~[hibernate-core-5.2.17.Final.jar:5.2.17.Final]
at org.hibernate.boot.internal.SessionFactoryBuilderImpl.build(SessionFactoryBuilderImpl.java:461) ~[hibernate-core-5.2.17.Final.jar:5.2.17.Final]
at org.hibernate.jpa.boot.internal.EntityManagerFactoryBuilderImpl.build(EntityManagerFactoryBuilderImpl.java:892) ~[hibernate-core-5.2.17.Final.jar:5.2.17.Final]
at org.springframework.orm.jpa.vendor.SpringHibernateJpaPersistenceProvider.createContainerEntityManagerFactory(SpringHibernateJpaPersistenceProvider.java:57) ~[spring-orm-5.0.6.RELEASE.jar:5.0.6.RELEASE]
at org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean.createNativeEntityManagerFactory(LocalContainerEntityManagerFactoryBean.java:365) ~[spring-orm-5.0.6.RELEASE.jar:5.0.6.RELEASE]
at org.springframework.orm.jpa.AbstractEntityManagerFactoryBean.buildNativeEntityManagerFactory(AbstractEntityManagerFactoryBean.java:390) ~[spring-orm-5.0.6.RELEASE.jar:5.0.6.RELEASE]
... 20 common frames omitted

我在这里缺少什么？

Answer 1

代表在您的班级中存储为字段。因此，它将被访问shop$delegate。

您可能还需要将委托标记为瞬态：

@delegate:Transient
@get:Transient
private val shop:Shop by lazy { shopService.shop(shopId!!) }

kotlin的JPA：懒惰和@Transient无法使用hibernate

1 个答案: