网络URL文件由后端获取以文件流方式传到前端下载

文件 从网络URL获取--》构建OutputStream对象--》一开始碰到乱码问题--》设置文件格式--》解决

  try {
           URL url = new URL("XXX");

           try {
               InputStream inputStream = url.openStream();
               int available = inputStream.available();
               System.out.println(available);
               OutputStream outputStream = response.getOutputStream(); 
               response.setContentType("application/x-download");
               response.addHeader("Content-Disposition", "attachment;filename="+"filenamedemo.xlsx");
               IOUtils.copy(inputStream, outputStream);
               outputStream.flush();
           } catch (Exception e) {
               e.printStackTrace();
           } 
       } catch (Exception e) { 
       }