如何在filter中注入bean

1. web.xml配置一个
2.           <filter>
3.                   <filter-name>DelegatingFilterProxy</filter-name>
4.                   <filter-class>org.springframework.web.filter.DelegatingFilterProxy</filter-class>
5.                   <init-param>
6.                           <param-name>targetBeanName</param-name>
7.                           <param-value>myFilter</param-value>
8.                   </init-param>
9.                   <init-param>
10.                           <param-name>targetFilterLifecycle</param-name>
11.                           <param-value>true</param-value>
12.                   </init-param>
13.           </filter>
14.
15.           <filter-mapping>
16.                   <filter-name>DelegatingFilterProxy</filter-name>
17.                   <url-pattern>/*</url-pattern>
18.           </filter-mapping>
19.
20.   applicationcontext.xml配置:
21.   <bean   id="myFilter"   class="skycncomp.util.CookieFilter">
22.   <property   name="userDao">
23.   <ref   bean="userDao"/>
24.   </property>
25.   </bean>
26.   <bean   id="userDao"   class="skycncomp.UserDAO">
27.   </bean>