I am trying to start by example from google, but still getting exeption “Resource not found”. Sorry for question, i am new to cuba as well as java 
This is source of example: راه اندازی سریع جاوا | Google Drive | Google Developers
Example service code:
package com.company.ramcovezmluvy.service;
import com.google.api.client.auth.oauth2.Credential;
import com.google.api.client.extensions.java6.auth.oauth2.AuthorizationCodeInstalledApp;
import com.google.api.client.extensions.jetty.auth.oauth2.LocalServerReceiver;
import com.google.api.client.googleapis.auth.oauth2.GoogleAuthorizationCodeFlow;
import com.google.api.client.googleapis.auth.oauth2.GoogleClientSecrets;
import com.google.api.client.googleapis.javanet.GoogleNetHttpTransport;
import com.google.api.client.http.javanet.NetHttpTransport;
import com.google.api.client.json.JsonFactory;
import com.google.api.client.json.jackson2.JacksonFactory;
import com.google.api.client.util.store.FileDataStoreFactory;
import com.google.api.services.drive.Drive;
import com.google.api.services.drive.DriveScopes;
import com.google.api.services.drive.model.File;
import com.google.api.services.drive.model.FileList;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.security.GeneralSecurityException;
import java.util.Collections;
import java.util.List;
public interface GoogleDriveService {
String NAME = "ramcovezmluvy_GoogleDriveService";
class DriveQuickstart {
private static final String APPLICATION_NAME = "Google Drive API Java Quickstart";
private static final JsonFactory JSON_FACTORY = JacksonFactory.getDefaultInstance();
private static final String TOKENS_DIRECTORY_PATH = "tokens";
/**
* Global instance of the scopes required by this quickstart.
* If modifying these scopes, delete your previously saved tokens/ folder.
*/
private static final List<String> SCOPES = Collections.singletonList(DriveScopes.DRIVE_METADATA_READONLY);
private static final String CREDENTIALS_FILE_PATH = "google_credentials.json";
/**
* Creates an authorized Credential object.
* @param HTTP_TRANSPORT The network HTTP Transport.
* @return An authorized Credential object.
* @throws IOException If the credentials.json file cannot be found.
*/
private static Credential getCredentials(final NetHttpTransport HTTP_TRANSPORT) throws IOException {
// Load client secrets.
InputStream in = DriveQuickstart.class.getResourceAsStream(CREDENTIALS_FILE_PATH);
if (in == null) {
throw new FileNotFoundException("Resource not found: " + CREDENTIALS_FILE_PATH);
}
GoogleClientSecrets clientSecrets = GoogleClientSecrets.load(JSON_FACTORY, new InputStreamReader(in));
// Build flow and trigger user authorization request.
GoogleAuthorizationCodeFlow flow = new GoogleAuthorizationCodeFlow.Builder(
HTTP_TRANSPORT, JSON_FACTORY, clientSecrets, SCOPES)
.setDataStoreFactory(new FileDataStoreFactory(new java.io.File(TOKENS_DIRECTORY_PATH)))
.setAccessType("offline")
.build();
LocalServerReceiver receiver = new LocalServerReceiver.Builder().setPort(8888).build();
return new AuthorizationCodeInstalledApp(flow, receiver).authorize("user");
}
public static void main(String... args) throws IOException, GeneralSecurityException {
// Build a new authorized API client service.
final NetHttpTransport HTTP_TRANSPORT = GoogleNetHttpTransport.newTrustedTransport();
Drive service = new Drive.Builder(HTTP_TRANSPORT, JSON_FACTORY, getCredentials(HTTP_TRANSPORT))
.setApplicationName(APPLICATION_NAME)
.build();
// Print the names and IDs for up to 10 files.
FileList result = service.files().list()
.setPageSize(10)
.setFields("nextPageToken, files(id, name)")
.execute();
List<File> files = result.getFiles();
if (files == null || files.isEmpty()) {
System.out.println("No files found.");
} else {
System.out.println("Files:");
for (File file : files) {
System.out.printf("%s (%s)\n", file.getName(), file.getId());
}
}
}
}
}
And this is exeption:
---- IntelliJ IDEA coverage runner ----
sampling ...
include patterns:
com\.company\.ramcovezmluvy\.service\..*
exclude patterns:
Exception in thread "main" java.io.FileNotFoundException: Resource not found: google_credentials.json
at com.company.ramcovezmluvy.service.GoogleDriveService$DriveQuickstart.getCredentials(GoogleDriveService.java:53)
at com.company.ramcovezmluvy.service.GoogleDriveService$DriveQuickstart.main(GoogleDriveService.java:70)
Class transformation time: 0.0186421s for 745 classes or 2.502295302013423E-5s per class
Process finished with exit code 1
Credentials file is located here(tried all options from example in cuba docs, but still same exeption):
