java web过滤器处理乱码

String encoding="utf-8"; request.setCharacterEncoding(enconding); response.setCharacterEncoding(enconding); 

<filter>  <filter-name>encodingFilter</filter-name>  <filter-class>com.scx.filter.Filter</filter-class>  <!-- 初始化参数 -->  <init-param>   <param-name>encoding</param-name>   <param-value>utf-8</param-value>  </init-param>  </filter>  <!-- filter映射关系 -->  <filter-mapping>  <filter-name>encodingFilter</filter-name>  <url-pattern>/*</url-pattern>  </filter-mapping> 

package com.scx.filter; import java.io.IOException; import javax.servlet.FilterChain; import javax.servlet.FilterConfig; import javax.servlet.ServletException; import javax.servlet.ServletRequest; import javax.servlet.ServletResponse; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; public class Filter implements javax.servlet.Filter{   //读取过滤器配置文件   private FilterConfig config;   public void destroy() {     // TODO Auto-generated method stub   }   public void doFilter(ServletRequest arg0, ServletResponse arg1,       FilterChain chain) throws IOException, ServletException {     // TODO Auto-generated method stub     HttpServletRequest request=(HttpServletRequest) arg0;     HttpServletResponse response=(HttpServletResponse) arg1;     String encoding=config.getInitParameter("encoding");     if(encoding==null||"".equals(encoding)){       encoding="utf-8";     }     request.setCharacterEncoding(encoding);     response.setCharacterEncoding(encoding);     chain.doFilter(request, response);   }   public void init(FilterConfig arg0) throws ServletException {     // TODO Auto-generated method stub     config=arg0;   } }