clean: improve code structure

src/main/java/eu/midnightdust/yaytris/Main.java

@@ -0,0 +1,22 @@
+package eu.midnightdust.yaytris;
+
+import javax.swing.UIManager;
+
+public class Main {
+
+    /**
+     * The application's entry point.
+     * Initializes the UI library to match the system style.
+     * Also loads saved settings, translations, and highscores from JSON.
+     *
+     * @param args   command line arguments – will be ignored
+     */
+    public static void main(String[] args) {
+        try {
+            System.setProperty("java.awt.headless", "false");
+            UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
+        } catch (Exception | Error e) { System.out.printf("%s: %s\n", "Error setting system look and feel", e); }
+        Tetris.init();
+    }
+
+}

src/main/java/eu/midnightdust/yaytris/Tetris.java

@@ -1,12 +1,12 @@
 package eu.midnightdust.yaytris;
 
 import eu.midnightdust.yaytris.game.Space;
+import eu.midnightdust.yaytris.game.Tetromino;
 import eu.midnightdust.yaytris.ui.ScoreMenu;
 import eu.midnightdust.yaytris.ui.TetrisUI;
 import eu.midnightdust.yaytris.util.GravityTimerTask;
 import eu.midnightdust.yaytris.util.sound.SoundUtil;
 
-import javax.swing.*;
 import java.time.LocalTime;
 import java.util.Random;
 import java.util.Timer;
@@ -20,30 +20,19 @@ public class Tetris {
     private static TimerTask gravityTask;
     private static LocalTime startTime;
 
-    /**
+    public static void init() {
-     * The application's entry point.
-     * Initializes the UI library to match the system style.
-     * Also loads saved settings, translations, and highscores from JSON.
-     *
-     * @param args   command line arguments – will be ignored
-     */
-    public static void main(String[] args) {
-        try {
-            System.setProperty("java.awt.headless", "false");
-            UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
-        } catch (Exception | Error e) { System.out.printf("%s: %s\n", "Error setting system look and feel", e); }
         Settings.load();
         Translation.load(Settings.language.locale);
         HighScores.load();
-        timer = new Timer("Tetris falling pieces");
+        Tetris.timer = new Timer("Tetris falling pieces");
-        space = new Space();
+        Tetris.space = new Space();
-        ui = new TetrisUI();
+        Tetris.ui = new TetrisUI();
     }
 
     /**
      * Get the active game space
      *
-     * @see          Space
+     * @see Space
      */
     public static Space getSpace() {
         return space;
@@ -52,7 +41,7 @@ public class Tetris {
     /**
      * Get the ui instance
      *
-     * @see          TetrisUI
+     * @see TetrisUI
      */
     public static TetrisUI getUi() {
         return ui;
@@ -61,7 +50,7 @@ public class Tetris {
     /**
      * Resets the game space, preparing it for a new game.
      *
-     * @see          Space
+     * @see Space
      */
     public static void resetSpace() {
         SoundUtil.stopMusic("/music/theme.wav");
@@ -72,9 +61,9 @@ public class Tetris {
 
     /**
      * Starts a new game of Tetris :D
-     * This involves starting our gravity task, playing music and spawning the first {@link eu.midnightdust.yaytris.game.Tetromino}
+     * This involves starting our gravity task, playing music and spawning the first {@link Tetromino}
      *
-     * @see          Space#spawnTetromino()
+     * @see Space#spawnTetromino()
      */
     public static void startGame() {
         SoundUtil.playMusic("/music/theme.wav", true);
@@ -88,8 +77,8 @@ public class Tetris {
      * Stops the current game.
      * Disables falling, fades out music and handles saving of high scores.
      *
-     * @see         ScoreMenu
+     * @see ScoreMenu
-     * @see         HighScores
+     * @see HighScores
      */
     public static void stopGame() {
         SoundUtil.stopMusic("/music/theme.wav");
@@ -97,32 +86,35 @@ public class Tetris {
         timer.purge();
         if (ui.getMenuPanel() instanceof ScoreMenu) ((ScoreMenu) ui.getMenuPanel()).gameOver();
         ui.transferFocus();
-        if (HighScores.diffToMap(Settings.difficulty).values().stream().noneMatch(hs -> hs > space.getScore())) ui.showHighscoreDialog(space.getScore());
+        if (HighScores.diffToMap(Settings.difficulty).values().stream().noneMatch(hs -> hs > space.getScore()))
+            ui.showHighscoreDialog(space.getScore());
     }
 
     /**
      * Updates the displayed score
      *
-     * @param score  the new score
+     * @param score the new score
-     * @see          ScoreMenu
+     * @see ScoreMenu
      */
     public static void updateScore(int score) {
         if (ui.getMenuPanel() instanceof ScoreMenu) ((ScoreMenu) ui.getMenuPanel()).updateScore(score);
         updateLevel(score);
     }
+
     /**
      * Updates the elapsed time
      *
-     * @see          ScoreMenu
+     * @see ScoreMenu
      */
     public static void updateTime() {
         if (ui.getMenuPanel() instanceof ScoreMenu) ((ScoreMenu) ui.getMenuPanel()).updateTime(startTime);
     }
+
     /**
      * Updates the displayed level
      *
-     * @param score  the new score, from which the level will be calculated
+     * @param score the new score, from which the level will be calculated
-     * @see          ScoreMenu
+     * @see ScoreMenu
      */
     public static void updateLevel(int score) {
         int newLevel = Math.max(0, (int) (score / 1400f));
@@ -136,5 +128,4 @@ public class Tetris {
             if (ui.getMenuPanel() instanceof ScoreMenu) ((ScoreMenu) ui.getMenuPanel()).updateLevel(newLevel);
         }
     }
-
+}
-}

src/main/java/eu/midnightdust/yaytris/ui/TetrisUI.java

@@ -64,7 +64,7 @@ public class TetrisUI extends JFrame implements KeyListener {
     private void rescale() {
         this.setSize((int) (400 * guiScale), (int) (320 * guiScale));
         titleLabel.setBounds(scale(225), scale(7), scale(110), scale(30));
-        titleLabel.setIcon(new ImageIcon(new ImageIcon(titleImage).getImage().getScaledInstance(scale(110), scale(30), Image.SCALE_DEFAULT)));
+        titleLabel.setIcon(new ImageIcon(titleImage.getScaledInstance(scale(110), scale(30), Image.SCALE_DEFAULT)));
         gamePanel.setBounds(scale(10), scale(10), scale(150), scale(282));
         this.setLocationRelativeTo(null);
     }
@@ -165,7 +165,7 @@ public class TetrisUI extends JFrame implements KeyListener {
      */
     public void showHighscoreDialog(int score) {
         String playerName = JOptionPane.showInputDialog(null, t("dialog.highscore.action"), t("dialog.highscore.title"), JOptionPane.PLAIN_MESSAGE);
-        HighScores.addScore(playerName, score);
+        if (playerName != null) HighScores.addScore(playerName, score);
     }
 
     /**