EncodingFilter

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;

public class EncodingFilter implements Filter
{

    String encoding = null;
    FilterConfig filterConfig = null;

    public void init(FilterConfig filterConfig) throws ServletException
    {
        this.filterConfig = filterConfig;
        this.encoding = filterConfig.getInitParameter("encoding");
    }

    public void doFilter(ServletRequest request, ServletResponse response,
            FilterChain chain) throws IOException, ServletException
    {
        if (encoding != null)
        {
            request.setCharacterEncoding(encoding);
        }
        chain.doFilter(request, response);
    }

    public void destroy()
    {
        this.encoding = null;
        this.filterConfig = null;
    }

}


<!-- web.xml设置-->
  <filter>
      <filter-name>encodingFilter</filter-name>
      <filter-class>com.dkflow.filter.EncodingFilter</filter-class>
      <init-param>
        <param-name>encoding</param-name>
        <param-value>gb2312</param-value>
      </init-param>
  </filter>
  <filter-mapping>
    <filter-name>encodingFilter</filter-name>
    <servlet-name>action</servlet-name>
  </filter-mapping>