How to parse a ResponseEntity in java and get a file with a name?

Question

Java

You need to download the file from the server. The file is generated dynamically, depending on the passed parameters, its name changes. Here is the controller that gives the file:

@PostMapping(value = "/getFile")
    public ResponseEntity<Resource> getNotFoundProviderGoods(@RequestParam("id") long id) throws IOException {
        File file = new File(getFile(id));
        InputStreamResource resource = new InputStreamResource(new FileInputStream(file));
        HttpHeaders headers = new HttpHeaders();
        headers.add(HttpHeaders.CONTENT_DISPOSITION, "attachment; filename=" + file.getName());

        return ResponseEntity.ok()
                .headers(headers)
                .contentLength(file.length())
                .contentType(MediaType.parseMediaType("application/octet-stream"))
                .body(resource);

    }

Next I get a ResponseEntity and I don't know how to extract the given file with its name...

CloseableHttpClient client = HttpClients.createDefault();
        HttpPost httpPost = new HttpPost("http://localhost:7587/getFile");
        httpPost.setHeader("X-CSRF-TOKEN", token);
        httpPost.setHeader("Cookie", cookie);
        HttpEntity reqEntity = MultipartEntityBuilder.create()
                .addTextBody("providerId", String.valueOf(id)).setCharset(Charset.forName("UTF-8"))
                .build();
        httpPost.setEntity(reqEntity);

        try (CloseableHttpResponse response = client.execute(httpPost)) {
            System.out.println(response);

            if (response.getStatusLine().getStatusCode() == HttpURLConnection.HTTP_OK) {
              ........... // как распарсить response ?
            }

how to parse response ?

Answer 1

It turned out in the following way:

try (CloseableHttpResponse response = client.execute(httpPost)) {
            if (response.getStatusLine().getStatusCode() == HttpURLConnection.HTTP_OK) {
                String fileName = response
                        .getHeaders("Content-Disposition")[0]
                        .getElements()[0]
                        .getParameterByName("filename")
                        .getValue();
                InputStream fis = response.getEntity().getContent();
                Files.copy(fis, new File(fileName).toPath(), StandardCopyOption.REPLACE_EXISTING);
                IOUtils.closeQuietly(fis);
            }
}

If there are suggestions for improving the code, I will be glad to see them.