struts 里面action的乱码问题？

把提交的页面的编码核对一下,最好用一个filter来过滤一下字符集

package com.sun.filter;

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.HttpServletRequest;

public class EncodingFilter implements Filter{
String encoding="GB18030";
public void destroy() {

}

public void doFilter(ServletRequest arg0, ServletResponse arg1, FilterChain chain) throws IOException, ServletException {
HttpServletRequest t=(HttpServletRequest)arg0;
t.setCharacterEncoding(this.encoding);
chain.doFilter(arg0, arg1);
}

public void init(FilterConfig config) throws ServletException {
this.encoding=config.getInitParameter("encoding");
System.out.print