@Entity 中的@Transactional 不起作用?

@Transactional in @Entity doesn't work?

进一步研究 Hibernate,我偶然发现了以下情况: 我有一个@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;
    }
}

分为两部分,不可变和可变:

@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);
    }
}

现在,当我尝试调用类似的东西时:

Session session = sessionFactory.openSession();
MutablePerson personFromDb = (MutablePerson) personService.getMutablePersonById(0);
personFromDb.excludeFromGroup(group1.getId());
session.saveOrUpdate(personFromDb);

我遇到异常:

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)

这告诉我,MutablePerson class 的 @Transactional 注释实际上不起作用,Hibernate 没有创建事务。

这是我的 spring 配置的一部分:

<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" />

据我从 Hibernate 文档和示例中可以看出,此配置是正确的并且它应该可以工作,但事实并非如此。我在这里错过了另一个 Hibernate 细微差别吗?

P.S。我知道我可以在 DAO 或服务 class 中完成此操作,但不幸的是我必须使用现有的 API,它与实体可变部分中的组一起工作。

实体不受 Spring 管理。它们是通过休眠或手动保存日期作为数据库操作的产物创建的。因此 @Transactional 注释将不起作用,因为这不是 spring 托管 bean。

Spring 事务上下文环绕 spring 托管 bean 并对其进行操作。它不能包装非 spring beans

可能的解决方案 理想地为服务层或至少 Jpa Repository/Dao 层移动事务上下文。