/**
   * 文件下載
   * @param filePath 文件路徑
   * @param fileName  文件名稱
   */
  public void download(String filePath,String fileName){
    try {
　　　　　　　//支持中文
      fileName = URLEncoder.encode(fileName,"UTF-8");
      HttpServletResponse response = ServletActionContext.getResponse();
      HttpServletRequest request = ServletActionContext.getRequest();
      response.reset();
      response.setContentType(request.getServletContext().getMimeType(fileName)); 
      response.setHeader("Content-Disposition", "attachment;filename="+fileName); 
      InputStream in = new FileInputStream(filePath); 
      OutputStream out = response.getOutputStream(); 
       
      byte[] b = new byte[1024];
      int length = 0;
      while((length = in.read(b)) != -1) { 
        out.write(b,0,length); 
      } 
      in.close(); 
      out.close();
    } catch (FileNotFoundException e) {
      e.printStackTrace();
    } catch (IOException e) {
      e.printStackTrace();
    }
  }