filter为什么不起作用？
我写了一个filter来过滤JSP页面的中文编码问题
单步调试的时候程序已经跳入filter了；但JSP页面上的中文数据传入BEAN的时候还是出现乱码问题；
我的JSP页面上设置了文件头：
<%@page   contentType= "text/html;   charset=GBK "%>
也面上的中文是正常显示的，就是在传值的时候出现乱码
我的filter代码如下：
package   com.wmf.struts;
//Decompiled   by   Jad   v1.5.7g.   Copyright   2000   Pavel   Kouznetsov.
//Jad   home   page:   http://www.geocities.com/SiliconValley/Bridge/8617/jad.html
//Decompiler   options:   packimports(3)   fieldsfirst   ansi  
//Source   File   Name:       Unknown   Source

import   java.io.IOException;
import   javax.servlet.*;
import   javax.servlet.http.HttpServlet;
import   javax.servlet.http.HttpServletResponse;

public   class   servfilter   extends   HttpServlet   implements   Filter   {
    private   FilterConfig   filterConfig;
    //Handle   the   passed-in   FilterConfig
    public   void   init(FilterConfig   filterConfig)   {
        this.filterConfig   =   filterConfig;
    }
    //Process   the   request/response   pair
    public   void   doFilter(ServletRequest   request,   ServletResponse   response,   FilterChain   filterChain)   {
        try   {
            response.setCharacterEncoding( "GBK ");
            request.setCharacterEncoding( "GBK ");
            response.setContentType( "text/html;   charset=GBK ");
                    ((HttpServletResponse)response).setHeader( "Pragma ", "No-cache ");
                    ((HttpServletResponse)response).setHeader( "Cache-Control ", "no-cache ");
                    ((HttpServletResponse)response).setHeader( "Expires ", "0 ");
            filterChain.doFilter(request,   response);
        }
        catch(ServletException   sx)   {
            filterConfig.getServletContext().log(sx.getMessage());
        }
        catch(IOException   iox)   {
            filterConfig.getServletContext().log(iox.getMessage());
        }
    }
    //Clean   up   resources
    public   void   destroy()   {
    }
}

web.xml里面的配置如下：
<filter>
        <filter-name> servfilter </filter-name>
        <filter-class> com.wmf.struts.servfilter </filter-class>
        <init-param>