Styjun

I tried to upload an image to google drive using drive API instructed on https://developers.google.com/drive/api/v3/quickstart/java.

public static final JsonFactory JSON_FACTORY = JacksonFactory.getDefaultInstance();
public static final String TOKENS_DIRECTORY_PATH = "E:/tokens";

public static final List<String> SCOPES = Collections.singletonList(DriveScopes.DRIVE_APPDATA);
public static final String CREDENTIALS_FILE_PATH = "credentials.json";
public static Credential getCredentials(Context context, final NetHttpTransport HTTP_TRANSPORT) throws IOException 
 InputStream in = context.getAssets().open(CREDENTIALS_FILE_PATH);
 GoogleClientSecrets clientSecrets = GoogleClientSecrets.load(JSON_FACTORY, new InputStreamReader(in));
 GoogleAuthorizationCodeFlow flow = new GoogleAuthorizationCodeFlow.Builder(
 HTTP_TRANSPORT, JSON_FACTORY, clientSecrets, SCOPES)
 .setDataStoreFactory(new FileDataStoreFactory(new java.io.File(TOKENS_DIRECTORY_PATH)))
 .setAccessType("offline")
 .build();
 return new AuthorizationCodeInstalledApp(flow, new LocalServerReceiver()).authorize("user");

And here where I call getCredentials method.

private void uploadImageToDrive(Uri uri) throws IOException, GeneralSecurityException
 try 
 GoogleDriveUpload gdu = new GoogleDriveUpload();
 final NetHttpTransport HTTP_TRANSPORT = new com.google.api.client.http.javanet.NetHttpTransport();
 Drive driveService = new Drive.Builder(HTTP_TRANSPORT, JSON_FACTORY, gdu.getCredentials(AccountInformationSignUpActivity.this, HTTP_TRANSPORT))
 .setApplicationName(APPLICATION_NAME)
 .build();
 String folderId = "1B7EWlFJUGmQ8qHHgMFIzuGL0i-eXl3J_";
 File fileMetadata = new File();
 fileMetadata.setName("photo.jpg");
 fileMetadata.setParents(Collections.singletonList(folderId));
 java.io.File filePath = new java.io.File(uri.getPath());
 FileContent mediaContent = new FileContent("image/jpeg", filePath);
 File file = driveService.files().create(fileMetadata, mediaContent)
 .setFields("id, parents")
 .execute();
 Log.d("File ID: ", file.getId());
 catch (FileNotFoundException e) 
 e.getStackTrace();
 

I put file credentials.json under main/assets/credentials.json
And It returns an error saying unable to create directory /tokens.
Is there any place where I'm wrong?