java - 没有 Hibernate Session 绑定(bind)到线程，并且配置不允许在此处创建非事务性 session

Question

当我调用使用 SessionFactory.getCurrentSession() 的 DAO 方法时出现此异常. DAO 类用 @Transactional 注释我也有<tx:annotation-driven/>在应用程序上下文配置文件中声明。

我可以调用我的 DAO 方法来执行 HQL 查询，但是每当我调用一个首先获取 Hibernate session 的 DAO 方法时，我就会遇到这个异常:

SEVERE: Failed to save the object.
org.hibernate.HibernateException: No Hibernate Session bound to thread, and configuration does not allow creation of non-transactional one here
    at org.springframework.orm.hibernate3.SpringSessionContext.currentSession(SpringSessionContext.java:63)
    at org.hibernate.impl.SessionFactoryImpl.getCurrentSession(SessionFactoryImpl.java:622)
    at gov.noaa.ncdc.cmb.persistence.dao.GenericDaoHibernateImpl.getCurrentSession(GenericDaoHibernateImpl.java:56)
    at gov.noaa.ncdc.cmb.persistence.dao.GenericDaoHibernateImpl.saveOrUpdate(GenericDaoHibernateImpl.java:187)

我有以下应用上下文配置文件:

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:aop="http://www.springframework.org/schema/aop"
       xmlns:flex="http://www.springframework.org/schema/flex"
       xmlns:tx="http://www.springframework.org/schema/tx"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xsi:schemaLocation="http://www.springframework.org/schema/beans
                           http://www.springframework.org/schema/beans/spring-beans-2.5.xsd
                           http://www.springframework.org/schema/flex
                           http://www.springframework.org/schema/flex/spring-flex-1.0.xsd
                           http://www.springframework.org/schema/tx
                           http://www.springframework.org/schema/tx/spring-tx-2.0.xsd">

    <!-- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ -->
    <!--  load values used for bean properties  -->
    <!-- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ -->
    <bean class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer">
        <property name="locations">
            <value>applicationContext.properties</value>
        </property>
    </bean>


    <!-- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ -->
    <!--  DataSource where objects will be persisted  -->
    <!-- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ -->
    <bean id="dataSource" class="org.springframework.jdbc.datasource.DriverManagerDataSource">
        <property name="username" value="${datasource.username}" />
        <property name="password" value="${datasource.password}" />
        <property name="url" value="${datasource.url}" />
        <property name="driverClassName" value="${datasource.driver}" />
    </bean>


    <!-- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ -->
    <!-- Factory bean for Hibernate Sessions -->
    <!-- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ -->
    <bean id="hibernateSessionFactory" class="org.springframework.orm.hibernate3.annotation.AnnotationSessionFactoryBean">
        <property name="dataSource" ref="dataSource" />
        <property name="annotatedClasses">
            <list>
                <value>gov.noaa.ncdc.cmb.esrl.domain.entity.EsrlDailyAvg</value>
                <value>gov.noaa.ncdc.cmb.esrl.domain.entity.EsrlObservations</value>
                <value>gov.noaa.ncdc.cmb.esrl.domain.entity.EsrlStation</value>
            </list>
        </property>
        <property name="hibernateProperties">
            <props>
                <prop key="hibernate.dialect">${hibernate.dialect}</prop>
                <prop key="hibernate.show_sql">false</prop>
                <prop key="hibernate.format_sql">true</prop>
                <prop key="hibernate.use_sql_comments">true</prop>
                <prop key="hibernate.jdbc.batch_size">50</prop>
                <prop key="hibernate.query.substitutions">true 1, false 0</prop>
                <prop key="hibernate.max_fetch_depth">6</prop>
                <prop key="hibernate.hbm2ddl.auto">${hibernate.hbm2ddlauto}</prop>
                <prop key="hibernate.cache.use_second_level_cache">${hibernate.use_second_level_cache}</prop>
            </props>
        </property>
    </bean>


    <!-- ~~~~~~~~~~~~~~~~~~~~~~~~~~ -->
    <!--  Transaction Manager bean  -->
    <!-- ~~~~~~~~~~~~~~~~~~~~~~~~~~ -->
    <bean id="transactionManager" class="org.springframework.orm.hibernate3.HibernateTransactionManager">
        <property name="sessionFactory" ref="hibernateSessionFactory" />
    </bean>


    <!-- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ -->
    <!--  enable the configuration of transactional behavior based on annotations  -->
    <!-- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ -->
    <tx:annotation-driven transaction-manager="transactionManager" />


    <!-- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ -->
    <!--  DAO for ESRL Station objects  -->
    <!-- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ -->
    <bean id="esrlStationDao" class="gov.noaa.ncdc.cmb.esrl.domain.dao.EsrlStationDaoHibernateImpl">
        <property name="sessionFactory" ref="hibernateSessionFactory" />
        <property name="persistentClass" value="gov.noaa.ncdc.cmb.esrl.domain.entity.EsrlStation" />
    </bean>


    <!-- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ -->
    <!--  DAO for ESRL Observations objects  -->
    <!-- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ -->
    <bean id="esrlObservationsDao" class="gov.noaa.ncdc.cmb.esrl.domain.dao.EsrlObservationsDaoHibernateImpl">
        <property name="sessionFactory" ref="hibernateSessionFactory" />
        <property name="persistentClass" value="gov.noaa.ncdc.cmb.esrl.domain.entity.EsrlObservations" />
    </bean>


    <!-- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ -->
    <!--  DAO for ESRL daily average objects  -->
    <!-- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ -->
    <bean id="esrlDailyAvgDao" class="gov.noaa.ncdc.cmb.esrl.domain.dao.EsrlDailyAvgDaoHibernateImpl">
        <property name="sessionFactory" ref="hibernateSessionFactory" />
        <property name="persistentClass" value="gov.noaa.ncdc.cmb.esrl.domain.entity.EsrlDailyAvg" />
    </bean>


</beans> 

通用 DAO 类(我的程序中使用的 DAO 从中扩展)如下所示:

package gov.noaa.ncdc.cmb.persistence.dao;

import gov.noaa.ncdc.cmb.persistence.entity.PersistentEntity;
import java.io.Serializable;
import java.util.Collection;
import java.util.Date;
import java.util.List;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.hibernate.Criteria;
import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.criterion.Criterion;
import org.hibernate.criterion.Example;

/**
 * This class is an implementation of GenericDao<T, PK> using Hibernate.
 */
public class GenericDaoHibernateImpl<T extends PersistentEntity<PK>, PK extends Serializable>
    implements GenericDao<T, PK>
{
    private SessionFactory sessionFactory;

    static private Log log = LogFactory.getLog(GenericDaoHibernateImpl.class);

    private Class<T> persistentClass;

    /**
     * Can be used within subclasses as a convenience method.
     * 
     * @param criterionList the criteria to find by
     * @return the list of elements that match the specified criteria
     */
    protected List<T> findByCriteria(final List<Criterion> criterionList)
    {
        Criteria criteria = getCurrentSession().createCriteria(persistentClass);
        for (Criterion criterion : criterionList)
        {
            criteria.add(criterion);
        }
        return criteria.list();
    }

    protected String getCanonicalPersistentClassName()
    {
        return persistentClass.getCanonicalName();
    }

    /**
     * Gets the current Hibernate Session object.
     * 
     * @return
     */
    protected Session getCurrentSession()
    {
        return sessionFactory.getCurrentSession();
    }

    /*
     * This method only provided for interface compatibility.  Not recommended for use with large batches 
     * (this is an inefficient implementation, and it's somewhat difficult to perform batch operations with Hibernate).
     * 
     * (non-Javadoc)
     * @see gov.noaa.ncdc.cmb.persistence.dao.GenericDao#batchInsert(java.util.Collection)
     */
    @Override
    public int[] batchInsert(final Collection<T> entityCollection)
    {
        int[] updateCounts = new int[entityCollection.size()];
        int i = 0;
        for (T entity : entityCollection)
        {
            try
            {
                saveOrUpdate(entity);
                updateCounts[i] = 1;
                i++;
            }
            catch (Exception ex)
            {
                clear();
                throw new RuntimeException(ex);
            }
        }
        flush();
        clear();

        return updateCounts;
    }

    /*
     * This method only provided for interface compatibility.  Not recommended for use with large batches 
     * (this is an inefficient implementation, and it's somewhat difficult to perform batch operations with Hibernate).
     * 
     * (non-Javadoc)
     * @see gov.noaa.ncdc.cmb.persistence.dao.GenericDao#batchUpdate(java.util.Collection)
     */
    @Override
    public int[] batchUpdate(final Collection<T> entityCollection)
    {
        return batchInsert(entityCollection);
    }

    /**
     * Completely clear the session. Evict all loaded instances and cancel all pending saves, updates and deletions. Do
     * not close open iterators or instances of ScrollableResults.
     */
    public void clear()
    {
        getCurrentSession().clear();
    }

    /*
     * (non-Javadoc)
     * @see gov.noaa.ncdc.cmb.persistence.dao.GenericDao#delete(gov.noaa.ncdc.cmb.persistence.entity.PersistentEntity)
     */
    @Override
    public void delete(final T persistentObject)
    {
        getCurrentSession().delete(persistentObject);
    }

    /*
     * (non-Javadoc)
     * @see gov.noaa.ncdc.cmb.persistence.dao.GenericDao#findAll()
     */
    @Override
    public List<T> findAll()
    {
        return getCurrentSession().createQuery("from " + persistentClass.getName()).list();
    }

    /**
     * Finds a collection of entity objects which match to the example instance, minus any specified properties which should be excluded from the matching.
     * 
     * @param exampleInstance
     * @param excludeProperty
     * @return
     */
    public List<T> findByExample(final T exampleInstance,
                                 final String[] excludeProperty)
    {
        Criteria criteria = getCurrentSession().createCriteria(persistentClass);
        Example example = Example.create(exampleInstance);
        if (excludeProperty != null)
        {
            for (String exclude : excludeProperty)
            {
                example.excludeProperty(exclude);
            }
        }
        criteria.add(example);
        return criteria.list();
    }

    /*
     * (non-Javadoc)
     * @see com.sun.cloud.lifecycle.core.persistence.dao.GenericDao#findById(java.io.Serializable)
     */
    @Override
    public T findById(final PK id)
    {
        return (T) getCurrentSession().load(persistentClass, id);
    }

    /**
     * Force this session to flush. Must be called at the end of a unit of work, before commiting the transaction and
     * closing the session (depending on flush-mode, Transaction.commit() calls this method).
     * 
     * Flushing is the process of synchronizing the underlying persistent store with persistable state held in memory.
     */
    public void flush()
    {
        getCurrentSession().flush();
    }

    /*
     * (non-Javadoc)
     * @see gov.noaa.ncdc.cmb.persistence.dao.GenericDao#saveOrUpdate(gov.noaa.ncdc.cmb.persistence.entity.PersistentEntity)
     */
    @Override
    public T saveOrUpdate(final T entity)
    {
        try
        {
            entity.setUpdatedDate(new Date());
            getCurrentSession().saveOrUpdate(entity);
            return entity;
        }
        catch (Exception ex)
        {
            String errorMessage = "Failed to save the object.";
            log.error(errorMessage, ex);
            throw new RuntimeException(errorMessage, ex);
        }
    }

    /**
     * Setter for the persistentClass property.
     * 
     * @param persistentClass
     */
    public void setPersistentClass(final Class<T> persistentClass)
    {
        this.persistentClass = persistentClass;
    }

    /**
     * Property setter.
     * 
     * @param sessionFactory
     */
    public void setSessionFactory(final SessionFactory sessionFactory)
    {
        this.sessionFactory = sessionFactory;
    }

}

我的应用程序从应用程序上下文中获取 DAO:

// load the Spring application context, get the DAOs
ApplicationContext applicationContext = new ClassPathXmlApplicationContext(new String[] { "dailyAveragingApplicationContext.xml" });
esrlDailyAvgDao = (EsrlDailyAvgDao) applicationContext.getBean("esrlDailyAvgDao");
esrlObservationsDao = (EsrlObservationsDao) applicationContext.getBean("esrlObservationsDao");

当我尝试保存实体时遇到异常:

esrlDailyAvgDao.saveOrUpdate(esrlDailyAvg);

DAO 类本身使用 Transactional 注解:

@Transactional
public class EsrlDailyAvgDaoHibernateImpl
    extends GenericDaoHibernateImpl<EsrlDailyAvg, Long>
    implements EsrlDailyAvgDao

异常堆栈跟踪如下所示:

SEVERE: Failed to save the object.
org.hibernate.HibernateException: No Hibernate Session bound to thread, and configuration does not allow creation of non-transactional one here
    at org.springframework.orm.hibernate3.SpringSessionContext.currentSession(SpringSessionContext.java:63)
    at org.hibernate.impl.SessionFactoryImpl.getCurrentSession(SessionFactoryImpl.java:622)
    at gov.noaa.ncdc.cmb.persistence.dao.GenericDaoHibernateImpl.getCurrentSession(GenericDaoHibernateImpl.java:56)
    at gov.noaa.ncdc.cmb.persistence.dao.GenericDaoHibernateImpl.saveOrUpdate(GenericDaoHibernateImpl.java:187)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
    at java.lang.reflect.Method.invoke(Unknown Source)
    at org.springframework.aop.support.AopUtils.invokeJoinpointUsingReflection(AopUtils.java:309)
    at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:196)
    at $Proxy19.saveOrUpdate(Unknown Source)
    at gov.noaa.ncdc.cmb.esrl.ingest.EsrlDailyAvgProcessor.main(EsrlDailyAvgProcessor.java:469)

Answer 1

我通过将 @Transactional 添加到基本/通用 Hibernate DAO 实现类(实现我在主程序中使用的 DAO 继承的 saveOrUpdate() 方法的父类)解决了这个问题，即@Transactional 需要在实现该方法的实际类上指定。相反，我的假设是，如果我在子类上声明 @Transactional ，那么它包含子类继承的所有方法。然而，@Transactional 注释似乎只适用于类中实现的方法，而不适用于类继承的方法。