我需要一个抽象的超类.
我有6个子类用于该抽象超类.
我使用JPA中的SINGLE_TABLE继承策略映射它们.
在另一个POJO中,我与这些1 + 6类有一对多的关系.
@OneToMany(mappedBy = "mSearchPreference", cascade = CascadeType.ALL)
private Set<SearchCriteria> mSearchCriteria;
这里"SearchCriteria"是抽象类.
@Entity
@Table(name = "SRCH_CRTR_T", schema = "LPEW")
@Inheritance(strategy=InheritanceType.SINGLE_TABLE)
@DiscriminatorColumn(name = "SRCH_DISCRIMINATOR_CDE", discriminatorType = DiscriminatorType.STRING)
@org.hibernate.annotations.ForceDiscriminator
public abstract class SearchCriteria extends BaseDBObject implements Comparable<SearchCriteria>
它有6个具体的子类类
@Entity
@DiscriminatorValue("DATE")
@Inheritance(strategy=InheritanceType.SINGLE_TABLE)
public class SearchCriteriaDateRange extends SearchCriteria
我可以将值插入表中,但是当我检索时出现错误:
Caused by: org.hibernate.WrongClassException: Object with id: 261 was not of the specified subclass: com.lmig.lit.lpew.model.criteria.SearchCriteria (Discriminator: DATE )
at org.hibernate.loader.Loader.getInstanceClass(Loader.java:1453)
at org.hibernate.loader.Loader.instanceNotYetLoaded(Loader.java:1284)
at org.hibernate.loader.Loader.getRow(Loader.java:1206)
at org.hibernate.loader.Loader.getRowFromResultSet(Loader.java:580)
at org.hibernate.loader.L
10:57:44,786 INFO [STDOUT] oader.doQuery(Loader.java:701) …我正在使用JPA与Hibernate持久性提供程序.
我用了一对多的映射
@OneToMany(mappedBy = "mSearchPreference", cascade = CascadeType.ALL, fetch=FetchType.EAGER)
我可以在控制台上看到一对多的SQL语句,尽管我得到了异常
illegal access to loading collection (hibernate.LazyInitializationException)
org.hibernate.LazyInitializationException: illegal access to loading collection
at org.hibernate.collection.AbstractPersistentCollection.initialize(AbstractPersistentCollection.java:341)
at org.hibernate.collection.AbstractPersistentCollection.read(AbstractPersistentCollection.java:86)
at org.hibernate.collection.AbstractPersistentCollection.readElementExistence(AbstractPersistentCollection.java:142)
at org.hibernate.collection.PersistentSet.add(PersistentSet.java:187)
有人可以帮我解决我需要做的其他安排吗？