关于flex与blazeDS和spring配置的问题？

Flex和Spring的整合：
1、将Spring的jar包拷贝到WEB-INF的lib下
2、在web.xml中注册Spring，如下配置：
<!-- Spring configuration file (Not needed if you don't use Spring) -->
<context-param>
<param-name>contextConfigLocation</param-name>
<param-value>/WEB-INF/applicationContext.xml</param-value>
</context-param>
<!-- Spring ContextLoaderListener (Not needed if you don't use Spring) -->
<listener>
<listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
</listener>
3、增加SpringFactory.java，代码如下：
package com.samples.factories;
import org.springframework.context.ApplicationContext;
import org.springframework.web.context.support.WebApplicationContextUtils;
import org.springframework.beans.BeansException;
import org.springframework.beans.factory.NoSuchBeanDefinitionException;
import flex.messaging.FactoryInstance;
impo