我正在尝试在我的服务类的 init 方法中从 DB 加载一些数据,但是当我调用“getResultList()”方法时,它会引发异常“会话已关闭”。
我的 applicationContext.xml
<bean class="org.springframework.orm.jpa.support.PersistenceAnnotationBeanPostProcessor" />
<bean id="testService" class="com.impl.TestServiceImpl" init-method="init" />
<bean id="transactionManager" class="org.springframework.orm.jpa.JpaTransactionManager">
<property name="entityManagerFactory" ref="entityManagerFactory" />
</bean>
<tx:annotation-driven transaction-manager="transactionManager" />
我的服务等级:
public Class TestServiceImpl implements TestService {
private EntityManager entityManager;
@PersistenceContext
public void setEntityManager(EntityManager entityManager) {
this.entityManager = entityManager;
}
public void init() {
Query query = entityManager.createQuery("from myTable");
query.getResultList(); // this causes error...
}
}
这是错误消息:
SEVERE: Exception sending context initialized event to listener instance of class
org.springframework.web.context.ContextLoaderListener
org.springframework.beans.factory.BeanCreationException: Error creating bean with name
'testService' defined in ServletContext resource [/WEB-INF/applicationContext.xml]:
Invocation of init method failed; nested exception is
javax.persistence.PersistenceException: org.hibernate.SessionException: Session is
closed!
Caused by: javax.persistence.PersistenceException: org.hibernate.SessionException:
Session is closed!
at
org.hibernate.ejb.AbstractEntityManagerImpl.throwPersistenceException(AbstractEntityManagerImpl.java:630)
那么我在这里做错了什么?我该如何解决这个问题?谢谢。