一直报错找不到怎么解决的方法 跟着老师写的，但是就是不行

报错内容：Error creating bean with name 'account.aop.test.AccountService2Test': Injection of resource dependencies failed; nested exception is org.springframework.beans.factory.BeanNotOfRequiredTypeException: Bean named 'accountService2Proxy' is expected to be of type 'account.aop.service.AccountService2Impl' but was actually of type 'com.sun.proxy.$Proxy30'

Caused by: org.springframework.beans.factory.BeanNotOfRequiredTypeException: Bean named 'accountService2Proxy' is expected to be of type 'account.aop.service.AccountService2Impl' but was actually of type 'com.sun.proxy.$Proxy30'

xml代码如下:

<!-- 注入dao -->
    <bean id="accountDao2" class="account.aop.dao.AccountDao2Impl">
        <property name="dataSource" ref="dataSource"/>
    </bean>

<!-- 注入service -->
    <bean id="accountService2" class="account.aop.service.AccountService2Impl">
        <property name="accountDao2" ref="accountDao2"/>
    </bean>
    
    
<!-- 通过context标签引入外部文件 -->
    <context:property-placeholder location="classpath:jdbc.properties"/>
     
<!-- 配置是C30连接池-->
    <bean id="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource">
         <property name="driverClass" value="${driverClassName}"/>
        <property name="jdbcUrl" value="${url}"/>
        <property name="user" value="${user}"/>
        <property name="password" value="${pass}"/>
     </bean>
     
     
<!-- 配置平台事务管理器============================= -->
    <bean id="transactionManager" class="org.springframework.jdbc.datasource.DataSourceTransactionManager">
        <property ref="dataSource" name="dataSource"/>
    </bean>
     
     
 <!-- 编写代理类，通过aop的前置增强的方法实现事物转账 -->
       <bean id="accountService2Proxy" class="org.springframework.transaction.interceptor.TransactionProxyFactoryBean">
         <!-- 注入事物管理器 -->
         <property name="transactionManager" ref="transactionManager"/>
         <!-- 配置目标对象 -->
         <property name="target" ref="accountService2"/>
         <!-- 注入事物属性 -->
         <property name="transactionAttributes">
             <props>
                 <prop key="transfer">PROPAGATION_REQUIRED</prop>
             </props>
         </property>
     </bean>   

测试类：package account.aop.test;

import javax.annotation.Resource;

import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.test.context.ContextConfiguration;
import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;

import account.aop.service.AccountService2Impl;
@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration("classpath:dl.xml")
public class AccountService2Test {
    //@Resource(name="accountService2")
    @Resource(name="accountService2Proxy")
    private AccountService2Impl accountService2;

    @Test
    public void test() {
        accountService2.transfer("zuo", "you", 300);
    }

}