Struts实时生成Excel文件下载

我做的项目原来是先在服务器上生成一个Excel文件，然后用jspsmartupload下载的，可是由于用jspsmartupload下载的excel文件由于编码问题会有损坏，而且服务器的压力也太大，所以改为在Action中生成excel文件，然后下载，方便多了。由于项目的原因，excel文件是实时生成的，对于jxl的使用，大家可以参考jxl相关的文章。
有什么问题可以和我联系。
MSN:whw_dream(AT)hotmail.com
代码如下：
test.jsp

<%@ taglib uri="/WEB-INF/struts-Html.tld" PRefix="html" %>
<html:html>
<html:button property="button" onclick="printAll()">
DownLoad
</html:button>
</html:html>
<script language='javascript'>
function printAll(){ location.href="<%=request.getContextPath()%><%=request.getContextPath()%>/download.do"; }
</script>

DownloadAction.Java

import org.apache.struts.action.*;
import javax.servlet.http.*;
import java.io.OutputStream;
import test.whw.upload.ExcelBean;
/**
 * <p>Title:DownloadAction </p>
 * <p>Description: QRRSMMS </p>
 * <p>Copyright: Copyright (c) 2004 jiahansoft</p>
 * <p>Company: jiahansoft</p>
 * @author wanghw
 * @version 1.0
 */

public class DownloadAction extends Action {
  public ActionForward execute(ActionMapping mapping,
                               ActionForm form,
                               HttpServletRequest request,
                               HttpServletResponse response)
      throws Exception {
    try{
      String fname = "test";//Excel文件名
      OutputStream os = response.getOutputStream();//取得输出流
      response.reset();//清空输出流
      response.setHeader("Content-disposition", "attachment; filename=" + fname + ".xls");//设定输出文件头