java - 如何使用 session 工厂关闭连接

Question

我是 spring mvc 和 hibernate 的新手。

如何在 Spring MVC 应用程序中关闭连接。我对这个问题感到非常沮丧。

这是我的代码:

调度程序 servlet:

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

    <context:component-scan base-package="com.kqics" />

    <bean id="viewResolver"
        class="org.springframework.web.servlet.view.InternalResourceViewResolver"
        p:prefix="/WEB-INF/jsp/" p:suffix=".jsp" />

    <bean id="userService" class="com.kqics.dao.kqtraveldao">
    </bean>

    <bean id="viewResolver1" class="org.springframework.web.servlet.view.ResourceBundleViewResolver">
        <property name="order" value="1"/>
        <property name="basename" value="views"/>
    </bean>

    <bean id="multipartResolver"
        class="org.springframework.web.multipart.commons.CommonsMultipartResolver">

        <!-- one of the properties available; the maximum file size in bytes -->
        <property name="maxUploadSize" value="10000000" />
    </bean>

    <import resource="db-config.xml" />

</beans>

dbconfig.xml

<?xml version="1.0" encoding="UTF-8"?>

<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xmlns:p="http://www.springframework.org/schema/p" 
       xmlns:tx="http://www.springframework.org/schema/tx"
       xmlns:aop="http://www.springframework.org/schema/aop"
       xmlns:context="http://www.springframework.org/schema/context"
       xsi:schemaLocation="
       http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
       http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.0.xsd
       http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-3.0.xsd
       http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-3.0.xsd
       http://www.springframework.org/schema/context
       http://www.springframework.org/schema/context/spring-context-3.0.xsd">

    <bean id="propertyConfigurer" class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer">
        <property name="location"><value>/WEB-INF/jdbc.properties</value></property>
</bean>


<bean id="dataSourceBean" lazy-init="true" class="com.mchange.v2.c3p0.ComboPooledDataSource" destroy-method="close">

        <property name="driverClass" value="${jdbc.driverClassName}" />
        <property name="jdbcUrl" value="${jdbc.url}" />
        <property name="user" value="${jdbc.username}" />
        <property name="password" value="${jdbc.password}"/>


        <property name="acquireIncrement" value="${jdbc.acquireIncrement}" />
        <property name="minPoolSize" value="${jdbc.minPoolSize}" />
        <property name="maxPoolSize" value="${jdbc.maxPoolSize}" />
        <property name="maxIdleTime" value="${jdbc.maxIdleTime}" />
        <property name="numHelperThreads" value="${jdbc.numHelperThreads}" />


    </bean>
    <bean id="sessionFactory" class="org.springframework.orm.hibernate3.annotation.AnnotationSessionFactoryBean"
                 p:dataSource-ref="dataSourceBean"
                 p:packagesToScan="com.kqics" >

        <property name="hibernateProperties">
        <props>
        <prop key="hibernate.dialect">${hibernate.dialect}</prop>
                <!--   <prop key="hibernate.hbm2ddl.auto">create</prop> --> 
        <prop key="hibernate.show_sql">true</prop>
        <prop key="hibernate.connection.release_mode">after_transaction</prop>
        <prop key="hibernate.connection.shutdown">true</prop>
        </props>
        </property>

    </bean>

    <!-- Transaction manager for a single Hibernate SessionFactory (alternative to JTA) -->
    <tx:annotation-driven/>

    <bean id="transactionManager" class="org.springframework.orm.hibernate3.HibernateTransactionManager">
        <property name="sessionFactory" ><ref bean="sessionFactory"/></property>

    </bean>


</beans>

我的服务类别:

@Service
public class kqtravellogservice implements ikqtravellogservice {

@Autowired
ikqtraveldao iDao;

@Transactional
public void serviceaddnewvehicle(kqvehicle obj) {
    // TODO Auto-generated method stub

    iDao.addnewvehicle(obj);

}

@Transactional
public List<kqvehicle> servicefetchallvehicle() {

    return iDao.fetchallvehicle();
}

@Transactional
public void serviceaddnewvehicletariff(kqvehicletariff obj,String tariff) {

    iDao.addnewvehicletariff(obj,tariff);

}

dao 实现

public class kqtraveldao implements ikqtraveldao {

    private HibernateTemplate hibernateTemplate;

    @Autowired
    public void setSessionFactory(SessionFactory sessionFactory) {
        try {
            hibernateTemplate = new HibernateTemplate(sessionFactory);

        } catch (Exception w) {
        }

    }


    @Override
    public void addnewvehicle(kqvehicle obj) {


        hibernateTemplate.save(obj);

    }

    @SuppressWarnings("unchecked")
    @Override
    public List<kqvehicle> fetchallvehicle() {

        List<kqvehicle> li=null;

    li=hibernateTemplate.find("from kqvehicle");


    return li;
    }

    @Override
        public void addnewvehicletariff(kqvehicletariff obj, String tariff) {

            try
            {
            hibernateTemplate.getSessionFactory()
            .openSession()
            .createSQLQuery("insert into "+tariff+" values(?,?,?,?,?)")
            .setParameter(0, obj.getTid())
            .setParameter(1, obj.getVehicletype())
            .setParameter(2, obj.getRupees())
            .setParameter(3, obj.getDateupto())
            .setParameter(4, obj.getDatetimedetermined())
            .executeUpdate();
            }
            catch(Exception e)
            {

            }
            finally
            {
                hibernateTemplate.getSessionFactory().close();

            }


        }

一些 friend 告诉我，因为我没有使用单例，连接关闭..所以，我收到了太多连接错误...请告诉我如何解决这个问题...

我的代码需要进行哪些更改......

Answer 1

问题出在你的 dao 中，你的保存方法正在破坏 spring 正确的 tx 管理。当您使用 Spring 管理连接和 session 时，切勿调用 openSession()。

而是使用 HibernateCallback ，它将为您提供 Spring 托管 session 。

@Override
public void addnewvehicletariff(final kqvehicletariff obj, final String tariff) {
    hibernateTemplate.execute(new HibernateCallback() {
        public Object doInHibernate(Session session) {
            session.createSQLQuery("insert into "+tariff+" values(?,?,?,?,?)")
            .setParameter(0, obj.getTid())
            .setParameter(1, obj.getVehicletype())
            .setParameter(2, obj.getRupees())
            .setParameter(3, obj.getDateupto())
            .setParameter(4, obj.getDatetimedetermined())
            .executeUpdate();   
        }
    }
}

另一个注意事项是，您不应该再使用 HibernateTemplate，您应该使用 上的 getCurrentSession() 方法针对普通 hibernate API 编写代码 session 工厂。请参阅http://docs.spring.io/spring/docs/current/spring-framework-reference/html/orm.html#orm-hibernate-straight了解更多信息。

public class kqtraveldao implements ikqtraveldao {

    private SessionFactory sessionFactory;

    @Autowired
    public void setSessionFactory(SessionFactory sessionFactory) {
        this.sessionFactory=sessionFactory;
    }

    @Override
    public void addnewvehicle(kqvehicle obj) {
        sessionFactory.getCurrentSession().save(obj);
    }

    @SuppressWarnings("unchecked")
    @Override
    public List<kqvehicle> fetchallvehicle() {
        return sessionFactory.getCurrentSession()
            .createQuery("from kqvehicle")
            .list(); 
    }

    @Override
    public void addnewvehicletariff(kqvehicletariff obj, String tariff) {
        sessionFactory.getCurrentSession()
        .createSQLQuery("insert into "+tariff+" values(?,?,?,?,?)")
        .setParameter(0, obj.getTid())
        .setParameter(1, obj.getVehicletype())
        .setParameter(2, obj.getRupees())
        .setParameter(3, obj.getDateupto())
        .setParameter(4, obj.getDatetimedetermined())
        .executeUpdate();
    }
}