Spring expression language not working with spring aop - spring

Question

<bean id="eddie" class="com.springinaction.Instrumentalist">
<property name="instrument" value="#{violin}"></property>
<property name="song" value="#{kenny.song}"></property>
</bean>
<bean id="violin" class="com.springinaction.Violin">
</bean>
<bean id="kenny" class="com.springinaction.Instrumentalist">
<property name="song" value="Kenny is a star,kenny is a star"></property>
<property name="instrument" ref="saxopone"></property>
</bean>
<aop:config>
<aop:aspect ref="audience">
<aop:before pointcut="execution(* com.springinaction.Performer.perform(..))" method="takeSeats()"/>
<aop:after-throwing method="demandRefund" pointcut="execution(* com.springinaction.Performer.perform(..))"/>
</aop:aspect>
</aop:config>
In the above code,I am injecting song , instrument property of eddie bean using spring expression language. But, song property not injected properly..and i am getting the below error:
Exception in thread "main"
org.springframework.beans.factory.BeanCreationException:
Error creating bean with name 'eddie'
defined in class path resource
[spring-config.xml]: Initialization of
bean failed; nested exception is
org.springframework.beans.factory.BeanExpressionException:
Expression parsing failed; nested
exception is
org.springframework.expression.spel.SpelEvaluationException:
EL1008E:(pos 6): Field or property
'song' cannot be found on object of
type '$Proxy4' at
org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:519)
at
org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:450)
at
org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:290)
at
org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:222)
at
org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:287)
at
org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:189)
at
org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:557)
at
org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:842)
at
org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:416)
at
org.springframework.context.support.ClassPathXmlApplicationContext.(ClassPathXmlApplicationContext.java:139)
at
org.springframework.context.support.ClassPathXmlApplicationContext.(ClassPathXmlApplicationContext.java:83)
at
com.springinaction.Main.main(Main.java:10)
Instrument property is injected properly where as song property is not injected and this is happening because of aop only..
when i comment out <aop:config> it is working fine..
Anything wrong?

Answer 1

Did you try
<aop:config proxy-target-class="true">
...
</aop:config>
This way you get a dynamic subclass and the property should be available in the proxy created via Spring AOP.
The default behaviour of Spring AOP is to create a Java proxy for the interfaces, so the properties of any classes won't be accessible through the proxy.