我有一个JSF应用程序，由于某些原因，我需要在浏览器返回按钮上刷新页面。我尝试实现Force JSF中给出的解决方案，通过BalusC的链接或返回按钮打开时刷新页面/视图/表单，唯一的区别是我的应用程序使用servlet 2.5版本运行，所以我在web. xml中做了如下映射

<?xml version="1.0" encoding="UTF-8"?>

http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd"id="WebApp_ID"version="2.5"

<filter>
    <filter-name>cacheFilter</filter-name>
    <filter-class>com.gaic.lpsr.utilclasses.NoCacheFilter.java</filter-class>
</filter>
<filter-mapping>
    <filter-name>cacheFilter</filter-name>
    <servlet-name>FacesServlet</servlet-name>

</filter-mapping>

我的过滤类是

public class NoCacheFilter implements Filter {

@Override
public void doFilter(ServletRequest req, ServletResponse res, FilterChain chain) throws IOException, ServletException {
    HttpServletRequest request = (HttpServletRequest) req;
    HttpServletResponse response = (HttpServletResponse) res;

    if (!request.getRequestURI().startsWith(request.getContextPath() + ResourceHandler.RESOURCE_IDENTIFIER)) { // Skip JSF resources (CSS/JS/Images/etc)
        response.setHeader("Cache-Control", "no-cache, no-store, must-revalidate"); // HTTP 1.1.
        response.setHeader("Pragma", "no-cache"); // HTTP 1.0.
        response.setDateHeader("Expires", 0); // Proxies.
    }

    chain.doFilter(req, res);
}

@Override
public void destroy() {
    // TODO Auto-generated method stub

}

@Override
public void init(FilterConfig arg0) throws ServletException {
    // TODO Auto-generated method stub

}

// ...

}

当我尝试在tomcat服务器（版本6.0.29）部署应用程序时，我得到以下错误。

SEVERE: Exception starting filter cacheFilter

请指导我如何解决这个问题。