feat: lab03 assigment

java2-lab02-v1/src/main/java/lab/ScoreStorageFactory.java

-package lab;
-
-import java.util.ArrayList;
-import java.util.List;
-import java.util.NoSuchElementException;
-import java.util.Random;
-import java.util.ServiceLoader;
-
-import cz.vsb.fei.java2.lab02.common.ScoreStorageInterface;
-import javafx.scene.control.Alert;
-import javafx.scene.control.ButtonType;
-import javafx.stage.Modality;
-import javafx.scene.control.Alert.AlertType;
-
-public class ScoreStorageFactory {
-
-	private static ScoreStorageInterface instance;
-
-	private ScoreStorageFactory() {
-		/* hide public one constructor */
-	}
-
-	public static ScoreStorageInterface getInstance() {
-		if (instance == null) {
-			List<ScoreStorageInterface> availableImplementations = new ArrayList<>();
-			ServiceLoader.load(ScoreStorageInterface.class).forEach(availableImplementations::add);
-			if (availableImplementations.isEmpty()) {
-				throw new NoSuchElementException(
-						"Service loader did not find any implementation of interface ScoreStorageInterface.");
-			}
-			instance = availableImplementations.get(new Random().nextInt(availableImplementations.size()));
-			Alert info = new Alert(AlertType.INFORMATION,
-					String.format("Storage %s selected.", instance.getClass().getName()), ButtonType.OK);
-			info.initModality(Modality.WINDOW_MODAL);
-			info.showAndWait();
-		}
-		return instance;
-	}
-}