java在web端直接输出Excel实现下载，javaweb输出excel,public Strin

java在web端直接输出Excel实现下载，javaweb输出excel,public Strin

public String excelDomnload() throws Exception{        try{            /*            String path = GlobalKeys.getFunctionConfig("user_attach_save","/opt/tmp/");            RegUser ru = ((RegUserLoginInfo) request.getSession().getAttribute(GlobalKeys.REG_USER_IN_SESSION_NAME)).getRegUser();            String tmpPath = File.separator + "import" + File.separator            + ru.getName() + File.separator;            File targetFolder = new File(path, tmpPath);//合并两个路经            String fName = request.getParameter("fName");            */            response.setContentType("application/msexcel;");                          response.setHeader("Content-Disposition", new String(("attachment;filename="+"error.xls").getBytes("GB2312"), "UTF-8"));            File f = new File("d:/20121211165820140_err.xls");            //File f = new File(targetFolder.getPath()+File.separator+fName);            FileInputStream in = new FileInputStream(f);            byte b[] = new byte[1024];            int i = 0;            ServletOutputStream out = response.getOutputStream();            while((i=in.read(b))!=  -1){                out.write(b, 0, i);            }            out.flush();            out.close();            in.close();        }catch(Exception e){            e.printStackTrace();        }        return null;    }