Add default cube path name

src/main/java/sh/ball/gui/Controller.java

@@ -134,6 +134,7 @@ public class Controller implements Initializable, FrequencyListener, Listener {
     this.audioPlayer = audioPlayer;
     FrameSet<List<Shape>> frames = new ObjParser(DEFAULT_OBJ).parse();
     frameSets.add(frames);
+    frameSetPaths.add("cube.obj");
     currentFrameSet = 0;
     frames.addListener(this);
     this.producer = new FrameProducer<>(audioPlayer, frames);

src/main/java/sh/ball/gui/Gui.java

@@ -36,8 +36,8 @@ public class Gui extends Application {
 
     scene.addEventHandler(KeyEvent.KEY_PRESSED, (event -> {
       switch (event.getCode()) {
-        case K -> controller.previousFrameSet();
         case J -> controller.nextFrameSet();
+        case K -> controller.previousFrameSet();
       }
     }));