在原来的SpringBoot–uploadfile项目基础上添加文件下载的Controller:
@RequestMapping(value = "/testDownload", method = RequestMethod.GET)
public void Download(HttpServletResponse res) {
String fileName = "1.png";
res.setHeader("content-type", "application/octet-stream");
res.setContentType("application/octet-stream");
res.setHeader("Content-Disposition",