使用SpringBoot从资源中下载一个文件

Question

如何从reosurces/folderX/file.txt 获取文件

@PostMapping(value = "/uploadFile", produces = MediaType.APPLICATION_OCTET_STREAM_VALUE)
public ResponseEntity<Resource> uploadFile(@RequestParam("file") MultipartFile file) {
/* 
* FIRST I upload file
* Next, I need to return different file in this request 
*/ 
return ResponseEntity.ok().header(HttpHeaders.CONTENT_DISPOSITION, "attachment; filename="" + "file.txt + """).body();
}

Answer 1

您可以提供这样的资源：

@GetMapping(value = "file")
public ResponseEntity<Resource> file() {
Resource resource = new ClassPathResource("folderX/file.txt");
HttpHeaders headers = new HttpHeaders();
headers.add(HttpHeaders.CONTENT_DISPOSITION, "attachment; filename="file.txt"");
return new ResponseEntity<>(resource, headers, HttpStatus.OK);
}