added UI with inventory and some notifications and an end screen + timer

src/de/miaurizius/jgame2d/entity/Player.java

@@ -16,7 +16,7 @@ public class Player extends Entity {
 
     public final int screenX;
     public final int screenY;
-    int hasKey = 0;
+    public int hasKey = 0;
 
     public Player(GamePanel panel, KeyHandler keyH) {
         this.panel = panel;
@@ -98,18 +98,27 @@ public class Player extends Entity {
                 panel.playSE(1);
                 hasKey++;
                 panel.obj[index] = null;
+                panel.ui.showMessage("You got a key!");
                 break;
             case "door":
                 if(hasKey > 0) {
                     panel.playSE(3);
                     panel.obj[index] = null;
                     hasKey--;
+                    panel.ui.showMessage("You opened the door!");
                 }
+                else panel.ui.showMessage("You need a key!");
                 break;
             case "boots":
                 panel.playSE(2);
                 speed += 1;
                 panel.obj[index] = null;
+                panel.ui.showMessage("Speed up!");
+                break;
+            case "chest":
+                panel.ui.gameFinished = true;
+                panel.stopMusic();
+                panel.playSE(4);
                 break;
         }
     }