spring+hibernate 新手问题，困扰已久，请大神看看啊！！！！

这是我报的错，
加了事务要织入时 就报错了， 说是pointcut-ref="dao"时出错 ，可是 我没有错误啊，请大神看看。。。。。

 Exception in thread "main" org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'sessionFactory' defined in class path resource [applicationContext.xml]: BeanPostProcessor before instantiation of bean failed; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'org.springframework.aop.support.DefaultBeanFactoryPointcutAdvisor#0': Cannot resolve reference to bean 'dao' while setting bean property 'pointcut'; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'dao': Instantiation of bean failed; nested exception is java.lang.NoClassDefFoundError: org/aspectj/weaver/reflect/ReflectionWorld$ReflectionWorldException

 <?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:aop="http://www.springframework.org/schema/aop"
    xmlns:tx="http://www.springframework.org/schema/tx"
    xmlns:context="http://www.springframework.org/schema/context"
    xmlns:p="http://www.springframework.org/schema/p"
    xsi:schemaLocation="http://www.springframework.org/schema/beans 
    http://www.springframework.org/schema/beans/spring-beans-3.2.xsd
    http://www.springframework.org/schema/aop
    http://www.springframework.org/schema/aop/spring-aop-3.2.xsd
    http://www.springframework.org/schema/context
    http://www.springframework.org/schema/context/spring-context-3.2.xsd
    http://www.springframework.org/schema/tx
    http://www.springframework.org/schema/tx/spring-tx-3.2.xsd">

    <bean id="sessionFactory" 
        class="org.springframework.orm.hibernate3.LocalSessionFactoryBean">
        <property name="configLocation" value="classpath:hibernate.cfg.xml"></property>
    </bean>
    <bean id="userDaoImpl" class="dao.UserDaoImpl" p:sessionFactory-ref="sessionFactory"></bean>

    <bean id="transactionManager" class="org.springframework.orm.hibernate3.HibernateTransactionManager"
        p:sessionFactory-ref="sessionFactory"></bean>

    <tx:advice id="txAdvice" transaction-manager="transactionManager">
        <tx:attributes>
            <tx:method name="get*"/>
            <tx:method name="*"/>
        </tx:attributes>
    </tx:advice>
    <aop:config>
        <aop:pointcut expression="execution(public * dao..*(..))" id="dao"/>
        <aop:advisor advice-ref="txAdvice" pointcut-ref="dao"/>
    </aop:config>
</beans>

java.lang.NoClassDefFoundError: org/aspectj/weaver/reflect/ReflectionWorld

没找到这个类，参考：http://blog.csdn.net/zxygww/article/details/45866757

报java.lang.ClassCastException: com.sun.proxy.$Proxy11 cannot be cast to dao.UserDaoImp
代理不能映射到dao.UserDaoImp 类，你仔细检查一下，这个类有没有。

我改成 userDao了 ，

我在 aop里 加了 proxy-target-class="true" 就可以了 ，请问下是什么原因

好 我找到原因了 ，谢谢各位