HttpServletRequest 转换成MultipartHttpServletRequest

//转换 HttpServletRequest
MultipartHttpServletRequest mulReq=(MultipartHttpServletRequest)request;
//获取上传的文件
CommonsMultipartFile file = (CommonsMultipartFile) mulReq.getFile("imageFile");
// 获取文件名称
String realFileName = file.getOriginalFilename();
System.out.println("文件名：" + realFileName);
//转换为 file
DiskFileItem fi = (DiskFileItem)file.getFileItem();
File files = fi.getStoreLocation();