Download File XML with Spring boot - file

Question

I'm trying to download files with a React front end, but the method in the controller doesn't download it
The method works because it doesn't launch any exception and the byte array works, but when I close the streams the download does not happen
public void downloadFile(#PathVariable("numeroOfferta") String numeroOfferta, #RequestParam(value="file") String file, HttpServletResponse response, HttpServletRequest req) throws IOException {
String filePathToBeServed =
File fileToDownload = new File(filePathToBeServed + file);
response.setContentType("application/octet-stream");
response.setHeader("Content-Disposition", "attachment;filename="+file);
response.setStatus(HttpServletResponse.SC_OK);
try(FileInputStream in = new FileInputStream(fileToDownload);
OutputStream out = response.getOutputStream()) {
byte[] buffer = new byte[4096];
while ((in.read(buffer, 0, 4096)) != -1) {
out.write(buffer, 0, 4096);
}
out.flush();
out.close();
in.close();
}
NumeroOfferta is just a String that I need to go inside folders and file contains the name of the file I send from the web page.
I can't understand why it doesn't download the file I choose despite the method works. Thank you for every answer

Answer 1

Simply use Spring MVC ResponseEntity:
public void downloadFile(#PathVariable("numeroOfferta") String numeroOfferta,
#RequestParam(value="file") String file) {
HttpHeaders headers = new HttpHeaders();
headers.setContentType(MediaType.APPLICATION_OCTET_STREAM);
headers.setContentDispositionFormData(file, file);
headers.setCacheControl("must-revalidate, post-check=0, pre-check=0");
byte[] content = Files.readAllBytes(new File(filePathToBeServed + file).toPath());
return new ResponseEntity(content, headers, HttpStatus.OK);
}
That's it.