import com.google.common.util.concurrent.FutureCallback;

import com.google.common.util.concurrent.Futures;

import com.google.common.util.concurrent.SettableFuture;

import com.wrapper.spotify.Api;

import com.wrapper.spotify.methods.authentication.ClientCredentialsGrantRequest;

import com.wrapper.spotify.models.ClientCredentials;

import static junit.framework.TestCase.fail;

/**

* This example shows how to get refresh an access token asynchronously. There's a

* synchronous version of the method available as well.

*

* The authorization flow used is documented in detail at

* https://developer.spotify.com/spotify-web-api/authorization-guide/#client-credentials-flow

* in the "Client Credentials" section.

*/

public class ApplicationAuthentication {

public static void main(String[] strings) {

final String clientId = "<insert client id>";

final String clientSecret = "<insert client secret>";

final Api api = Api.builder()

.clientId(clientId)

.clientSecret(clientSecret)

.build();

/* Create a request object. */

final ClientCredentialsGrantRequest request = api.clientCredentialsGrant().build();

/* Use the request object to make the request, either asynchronously (getAsync) or synchronously (get) */

final SettableFuture<ClientCredentials> responseFuture = request.getAsync();

/* Add callbacks to handle success and failure */

Futures.addCallback(responseFuture, new FutureCallback<ClientCredentials>() {

@Override

public void onSuccess(ClientCredentials clientCredentials) {

/* The tokens were retrieved successfully! */

System.out.println("Successfully retrieved an access token! " + clientCredentials.getAccessToken());

System.out.println("The access token expires in " + clientCredentials.getExpiresIn() + " seconds");

/* Please note that this flow does not return a refresh token.

* That's only for the Authorization code flow */

}

@Override

public void onFailure(Throwable throwable) {

/* An error occurred while getting the access token. This is probably caused by the client id or

* client secret is invalid. */

fail("Failed to resolve future: " + throwable.getMessage());

}

});

}

}