中文转码Filter

在Struts中经常会碰到中文转码的问题，最简单的办法就是直接写一个ServletFilter
代码如下：
ChineseFilter.class


import java.io.IOException;
import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.FilterConfig;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

public class ChineseFilter extends HttpServlet implements Filter {

 private FilterConfig filterConfig;
     //Handle the passed-in FilterConfig
     public void init(FilterConfig filterConfig) throws ServletException {
         this.filterConfig = filterConfig;
     }
     //Process the request/response pair
     public void doFilter(ServletRequest request, ServletResponse response,
                          FilterChain filterChain) {
         try {
          
          String encoding=filterConfig.getInitParameter("encoding");//从WEB.xml配置文件中取出参数，这样我们可以通过配置修改编码格式．                  
             request.setCharacterEncoding(encoding);//设置请求的编码格式
             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() {
     }

  protected void doGet(HttpServletRequest arg0, HttpServletResponse arg1) throws ServletException, IOException {
   // TODO Auto-generated method stub
   super.doGet(arg0, arg1);  
  }

  protected void doPost(HttpServletRequest arg0, HttpServletResponse arg1) throws ServletException, IOException {
   // TODO Auto-generated method stub
   super.doPost(arg0, arg1);   
  } 
}

写完过滤器剩下的就是配置Web.xml了

 <filter>
  <filter-name>ChineseFilter</filter-name>
  <filter-class>com.blog.filter.ChineseFilter</filter-class>
<init-param>
    <param-name>encoding</param-name>
    <param-value>GBK</param-value>　配置编码格式，可以配置成你想要的编码（GBK,bg-2312）
</init-param>
  </filter>
   <filter-mapping>
    <filter-name>ChineseFilter</filter-name>
    <url-pattern>/*</url-pattern>
  </filter-mapping>

好了，简单的Filter就完成了．当然也有现成的包，比如你用Struts+Spring的话，那Spring中就有现成的转码过滤器，我们只要在WEB．xml中配置一下就OK了．

＜filter＞
＜filter-name＞encodingFilter＜/filter-name＞
 ＜filter-class＞org.springframework.web.filter.CharacterEncodingFilter＜/filter-class＞
 ＜init-param＞
 ＜param-name＞encoding＜/param-name＞
. ＜param-value＞GBK＜/param-value＞
 ＜/init-param＞
 ＜/filter＞
＜filter-mapping＞
 ＜filter-name＞encodingFilter＜/filter-name＞
 ＜url-pattern＞/*＜/url-pattern＞
 ＜/filter-mapping＞