spring 整合Filter
一、使用spring提供的代理类—elegatingFilterProxy）整合Filter

1.编写类并实现Filter接口

3.修改web.xml如下：
    <filter>        <filter-name>authenticationFilter</filter-name>        <filter-class>com.test.AuthenticationFilter</filter-class>    </filter>    <filter-mapping>         <filter-name>authenticationFilter</filter-name>         <url-pattern>/*</url-pattern>     </filter-mapping>