Reputation: 298
Going further into Hibernate i've stumbled upon the following situation: I have an @Entity Person
@Entity
@Table(name = "PERSON")
@Inheritance(strategy = InheritanceType.SINGLE_TABLE)
@DiscriminatorColumn(name="type",discriminatorType=DiscriminatorType.STRING)
@DiscriminatorValue(value="person")
public class Person implements PersonInterface{
@Id
@GeneratedValue(strategy = GenerationType.IDENTITY)
@Column(name = "USER_ID")
protected Integer id;
@Column(name = "NAME")
protected String name;
@ElementCollection
@Formula("(SELECT groupId FROM PERSON_GROUPS WHERE id = id")
protected List<Integer> groups = new ArrayList<>();
@Override
public Integer getId() {
return id;
}
@Override
public Collection<Integer> getGroups(){
return groups;
}
@Override
public String getName() {
return name;
}
}
Which is split in two parts, Immutable and Mutable:
@Entity
@DiscriminatorValue("mutableperson")
@Transactional
public class MutablePerson extends Person implements MutablePersonInterface{
@Override
public void setName(String name) {
this.name = name;
}
@Override
public void setId(Integer id) {
this.id = id;
}
@Override
public void setGroups(List<Integer> groupIds) {
this.groups = groupIds;
}
public void excludeFromGroup(Integer groupId){
Hibernate.initialize(this.groups);
this.groups.remove(groupId);
}
}
Now, when i try to call something like:
Session session = sessionFactory.openSession();
MutablePerson personFromDb = (MutablePerson) personService.getMutablePersonById(0);
personFromDb.excludeFromGroup(group1.getId());
session.saveOrUpdate(personFromDb);
I get an exception:
Exception in thread "main" org.hibernate.HibernateException: collection is not associated with any session
at org.hibernate.collection.internal.AbstractPersistentCollection.forceInitialization(AbstractPersistentCollection.java:704)
at org.hibernate.Hibernate.initialize(Hibernate.java:65)
at com.studytrails.tutorials.springhibernatejpa.MutablePerson.excludeFromGroup(MutablePerson.java:57)
at com.studytrails.tutorials.springhibernatejpa.TestSpringHibernateJpa.main(TestSpringHibernateJpa.java:48)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:497)
at com.intellij.rt.execution.application.AppMain.main(AppMain.java:144)
Which tells me, that @Transactional annotation for that MutablePerson
class doesn't really work and Hibernate is not creating a transaction.
Here's this bit of my spring configuration:
<bean id="transactionManager" class="org.springframework.orm.jpa.JpaTransactionManager">
<property name="entityManagerFactory" ref="entityManagerFactory" />
<property name="dataSource" ref="dataSource" />
<property name="jpaDialect" ref="jpaDialect" />
</bean>
<tx:annotation-driven transaction-manager="transactionManager" />
As far as i can tell from Hibernate docs and examples, this config is correct and it should work, but it doesn't. Am i missing yet another Hibernate nuance here?
P.S. I know i could've done this in DAO or Service class, but unfortunately i'm bound to use existing API, which works with groups in the mutable half of the entity.
Upvotes: 0
Views: 1505
Reputation: 446
Entities are not managed by Spring. they are created as a product of database operation via hibernate or manually to save date. therefore the @Transactional annotation will not work as this is not a spring managed bean.
Spring transactional context wraps around a spring managed bean and act on it. it cannot wrap non spring beans
Possible Solution Move the transactional context ideally for service layer or at least Jpa Repository/Dao layer.
Upvotes: 1