web.xml文件中需要添加的代码：

<web-app>

……

  <filter>
   <filter-name>Set Character Encoding</filter-name>
   <filter-class>struts.filter.SetCharacterEncodingFilter</filter-class>
   <init-param>
    <param-name>encoding</param-name>
    <param-value>UTF-8</param-value>
   </init-param>
  </filter>
  <filter-mapping>
   <filter-name>Set Character Encoding</filter-name>
   <url-pattern>/*</url-pattern>
  </filter-mapping>

……

</web-app>

其中在上面的代码中提到的struts.filter.SetCharacterEncodingFilter也是需要添加的class文件(并且要注意路径哦，可以不和我的一样，但自己的一定要一致哦！)

struts.filter.SetCharacterEncodingFilter 文件代码如下：

package struts.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;

public class SetCharacterEncodingFilter implements Filter {
 
 protected String encoding = null;
 protected FilterConfig filterConfig = null;
 protected boolean ignore = true;

 public void destroy() {
  this.encoding = null;
  this.filterConfig = null;
 }
 
 public void doFilter(ServletRequest request, ServletResponse response,FilterChain chain)throws IOException, ServletException {
  if (ignore || (request.getCharacterEncoding() == null)) {
   String encoding = selectEncoding(request);
   if (encoding != null)
    request.setCharacterEncoding(encoding);
  }
  chain.doFilter(request, response);
 }
 
 public void init(FilterConfig filterConfig) throws ServletException {
  this.filterConfig = filterConfig;
  this.encoding = filterConfig.getInitParameter("encoding");
  String value = filterConfig.getInitParameter("ignore");
  if (value == null)
   this.ignore = true;
  else if (value.equalsIgnoreCase("true"))
   this.ignore = true;
  else if (value.equalsIgnoreCase("yes"))
   this.ignore = true;
  else
   this.ignore = false;
 }
 
 protected String selectEncoding(ServletRequest request) {
  return (this.encoding);
 }
 
}