"error_description": "client_secret is missing." - oauth-2.0

Question

Hello team I have a Application on https://console.cloud.google.com of type Desktop
once after signin with the test user credentials , i have returned successfully and then trying to get the token using the
final String tokenUrl = "https://oauth2.googleapis.com/token";
// The original redirect URL
final URI redirectUri = new URI(this.redirectUri);
// Using HttpClient to make the POST to exchange the auth code for the token
HttpClient client = HttpClientBuilder.create().build();
HttpPost post = new HttpPost(tokenUrl);
// Adding the POST params to the request
List<NameValuePair> urlParameters = new ArrayList<NameValuePair>();
urlParameters.add(new BasicNameValuePair("code", code));
urlParameters.add(new BasicNameValuePair("client_id", googleClientId));
urlParameters.add(new BasicNameValuePair("client_secret", googleClientsecret));
urlParameters.add(new BasicNameValuePair("redirect_uri", redirectUri.toString()));
urlParameters.add(new BasicNameValuePair("scope", scope));
urlParameters.add(new BasicNameValuePair("grant_type", grantType));
post.setEntity(new UrlEncodedFormEntity(urlParameters));
// Execute the request
System.out.println(post.toString());
HttpResponse response = client.execute(post);
// Print the status code
System.out.println("Response Code : " + response.getStatusLine().getStatusCode());
// Get the content as a String
String content = EntityUtils.toString(response.getEntity());
System.out.println("Result : " + content.toString());
am getting the error as below
Response Code : 400
Result : {
"error": "invalid_request",
"error_description": "client_secret is missing."
}
i know am not using google API's to get the token , but the api here am using also should work right?
please please help me here