spring容器无法注入Hibernate

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

<beans

	xsi:schemaLocation="http://www.springframework.org/schema/beans  

http://www.springframework.org/schema/beans/spring-beans-3.2.xsd"

	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://www.springframework.org/schema/beans">

	

	<bean id="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource">

		<property name="driverClass" value="com.mysql.jdbc.Driver" />

		<property name="jdbcUrl"

			value="jdbc:mysql://localhost:3306/xuexiao?characterEncoding=UTF8" />

		<property name="user" value="root"></property>

		<property name="password" value="123456"></property>

		<property name="minPoolSize">

			<value>1</value>

		</property>

		<property name="maxPoolSize">

			<value>20</value>

		</property>

	</bean>

	<bean id="sessionFactory"

		class="org.springframework.orm.hibernate4.LocalSessionFactoryBean">

		<property name="dataSource">

			<ref bean="dataSource" />

		</property>

		<property name="hibernateProperties">

			<props>

				<prop key="hibernate.dialect">

					org.hibernate.dialect.MySQLDialect

				</prop>

			</props>

		</property>

		<property name="mappingResources">

			<list>

				<value>com/hibernate/bean/User.hbm.xml</value>

			</list>

		</property>

	</bean>

	<bean id="myAction" class="com.hibernate.servlet.MyAction"></bean>

</beans> 

public class Userdao {

	private SessionFactory sessionFactory;

	public SessionFactory getSessionFactory() {

		return sessionFactory;

	}



	public void setSessionFactory(SessionFactory sessionFactory) {

		this.sessionFactory = sessionFactory;

	}

	public boolean addUser(User user){

		Session session=null;

		try {

			session = sessionFactory.openSession();

			session.getTransaction().begin();

			session.save(user);

			session.getTransaction().commit();

		} catch (Exception e) {

			// TODO: handle exception

			return false;

		}finally{

			session.close();

		}

		return true;

	}

}

一直提示sessionFactory为空，myAction已经实例化了。为什么sessionFactory一直提示为空。
------解决方案--------------------
需要在你的applicationContext.xml中配置

<bean id="usrDao" class="xx.xx.Userdao">

      <property name="sessionFactory">

            <ref bean="sessionFactory" />

        </property>

</bean>