代码:
util类

if(workbook !=null){
            	OutputStream out=null;
                try
                {
                    String fileName = "Excel-" + String.valueOf(System.currentTimeMillis()).substring(4, 13) + ".xls";
                    String headStr = "attachment; filename=\"" + fileName + "\"";
                    //
                    //response.reset();
                    response.setContentType("APPLICATION/OCTET-STREAM");
                    response.setHeader("Content-Disposition", headStr);
                    out = response.getOutputStream();
                    System.out.println("fileName:"+fileName);
                    System.out.println("开始写文件#####################");
                    workbook.write(out);
                    out.close();
                    
                }
                catch (IOException e)
                {
                    e.printStackTrace();
                }
                finally {
                	out.close();
                }

controller:

ExportExcel ex = new ExportExcel(title, rowsName, dataList);
        HttpServletResponse response=Mvcs.getResp();
        ex.export(response);
        System.out.println();