java下载文件

public void daochu(){
  try {
   String path=ServletActionContext.getServletContext().getRealPath("/")+" \\"+xlsName;//获取生成的excel的路径
     File file=new File(path);
     String filename = URLEncoder.encode(xlsName.replaceAll(" ", ""),"UTF-8");//去除文件名中的空格
      if (filename.length() > 150) { 
          filename = new String(filename.getBytes("gb2312"), "ISO8859-1");   //防止文件名出现乱码
       }
    response.setContentType("application/vnd.ms-excel;charset=UTF-8");
   response.setHeader("Content-Disposition", "attachment;"+ "filename="+filename);
   response.getOutputStream().write(FileUtils.readFileToByteArray(file));
   file.delete();//下载完成后删除文件
  } catch (Exception e) {
   e.printStackTrace();
  }finally{
   try {
    response.getOutputStream().close();
   } catch (Exception e) {
    e.printStackTrace();
   }
  }
 }