private String fileName;

private String extension;

private byte[] file;

//getter and setter

//getter and setter

private String fileName;
private String extension;
private byte[] file;

//getter and setter

//getter and setter

HttpHeaders headers = new HttpHeaders();
    headers.add("user-agent", "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/54.0.2840.99 Safari/537.36");
    headers.add("X-CSRF-TOKEN",  csrfToken);
    headers.add("JSESSIONID",  jSessionId);
    headers.add("Cookie",  cookie);
    headers.add("Content-Type",  "application/json");

    return headers;
}


public String postRuhsat (Ruhsat ruhsat){
    RestTemplate restTemplate = new RestTemplate();

    String applyNum = "";
    HttpEntity<Ruhsat> request = new HttpEntity<>(ruhsat,postHeader());
    ResponseEntity response = restTemplate.exchange(appProperties.getRuhsatRestUrl(), HttpMethod.POST, request, String.class);
    //ResponseEntity response = restTemplate.postForObject(appProperties.getRuhsatRestUrl(), request, ResponseEntity.class);
    //I try above code even so null in restapi project
    if (response.getStatusCode() == HttpStatus.OK){
        applyNum = response.getBody().toString();
        postFile(ruhsat, applyNum);
    }

    return applyNum;
}