How do I use Paging<> objects with the Spotify API in Java?

Question

Apologies if this question is easily figured out, I'm quite new to Java and working with the Spotify API. I am using this Spotify Web API Java Package for a web application and am trying to implement a simplified Track Search method. I'm having trouble trying to figure out how to get the information I want after calling the method, which returns a Paging object. The Paging object is a container that holds a set of Track objects. The package I'm using gives a link to Paging<> objects in the Spotify API Documentation, but the Object Model Specifications page has apparently been removed and makes the link useless.

Here's the class I made (the client ID and secret have been omitted of course and the class does work with other methods that just return a float, int or String):

package trackour.trackour.views.api;

import java.io.IOException;

import org.apache.hc.core5.http.ParseException;

import com.neovisionaries.i18n.CountryCode;

import se.michaelthelin.spotify.SpotifyApi;
import se.michaelthelin.spotify.exceptions.SpotifyWebApiException;
import se.michaelthelin.spotify.model_objects.credentials.ClientCredentials;
import se.michaelthelin.spotify.model_objects.specification.Paging;
import se.michaelthelin.spotify.model_objects.specification.Track;
import se.michaelthelin.spotify.requests.authorization.client_credentials.ClientCredentialsRequest;
import se.michaelthelin.spotify.requests.data.search.simplified.SearchTracksRequest;

// Class to control the Spotify API and access its endpoints by using the Spotify Web API Java package
// Each method is public and static to easily use them throughout the application.
// ex. APIController.getAcousticness("ID GOES HERE");
public class APIController {

    // create a SpotifyApi Builder object and set the Client ID and Client Secret
    private static final SpotifyApi spotifyAPI = new SpotifyApi.Builder()
        .setClientId(CLIENT_ID)
        .setClientSecret(CLIENT_SECRET)
        .build();

    // create a ClientCredentialsRequest object which allows access to access tokens
    private static final ClientCredentialsRequest clientCredentialsRequest = spotifyAPI.clientCredentials()
        .build();

    public static Paging<Track> searchTracks(String title) {
        try {
            final ClientCredentials clientCredentials = clientCredentialsRequest.execute();

            spotifyAPI.setAccessToken(clientCredentials.getAccessToken());

            final SearchTracksRequest searchTracksRequest = spotifyAPI.searchTracks(title)
                .market(CountryCode.CA)
                .limit(5)
                .offset(0)
                .build();

            final Paging<Track> trackPaging = searchTracksRequest.execute();

            return trackPaging;
            
        } catch (IOException | SpotifyWebApiException | ParseException e) {
            System.out.println(e.getMessage());
            return null;
        }
    }

    // TESTING
    public static void main(String[] args) {
        Paging<Track> test = searchTracks("Abba");
        System.out.println(test.getTotal());
    }
}

The code I have in the main function works and returns a Paging object which I can then get the total items the object has, but I can't get the information from each individual item. I've tried looking up the problem or a solution but I can't seem to find anything that would help me.

Answer 1

The Spotify Web API javadocs say that Paging<T> has a method .getItems() which in your case would return an array of Tracks.

For example,

    public static void main(String[] args) {
        Paging<Track> test = searchTracks("Abba");
        Track[] tracks = test.getItems();
        System.out.println(Arrays.toString(tracks));
    }

would print out all the tracks.