diff --git a/core/src/netwerkprog/game/util/game/GameCharacter.java b/core/src/netwerkprog/game/util/game/GameCharacter.java
index ecd4da3..1f017e5 100644
--- a/core/src/netwerkprog/game/util/game/GameCharacter.java
+++ b/core/src/netwerkprog/game/util/game/GameCharacter.java
@@ -1,6 +1,5 @@
 package netwerkprog.game.util.game;
 
-
 import com.badlogic.gdx.graphics.g2d.TextureRegion;
 import com.badlogic.gdx.scenes.scene2d.Actor;
 import netwerkprog.game.client.game.map.GameTile;
diff --git a/core/src/netwerkprog/game/util/graphics/FrameRate.java b/core/src/netwerkprog/game/util/graphics/FrameRate.java
index fdf3e18..501020d 100644
--- a/core/src/netwerkprog/game/util/graphics/FrameRate.java
+++ b/core/src/netwerkprog/game/util/graphics/FrameRate.java
@@ -17,8 +17,8 @@ public class FrameRate implements Disposable{
     long lastTimeCounted;
     private float sinceChange;
     private float frameRate;
-    private BitmapFont font;
-    private SpriteBatch batch;
+    private final BitmapFont font;
+    private final SpriteBatch batch;
     private OrthographicCamera cam;
 
 
diff --git a/core/src/netwerkprog/game/util/graphics/TextRenderer.java b/core/src/netwerkprog/game/util/graphics/TextRenderer.java
index 158b521..769a80b 100644
--- a/core/src/netwerkprog/game/util/graphics/TextRenderer.java
+++ b/core/src/netwerkprog/game/util/graphics/TextRenderer.java
@@ -7,8 +7,8 @@ import com.badlogic.gdx.graphics.g2d.SpriteBatch;
 import com.badlogic.gdx.utils.Disposable;
 
 public class TextRenderer implements Disposable {
-    private BitmapFont font;
-    private SpriteBatch batch;
+    private final BitmapFont font;
+    private final SpriteBatch batch;
     private OrthographicCamera cam;
 
     public TextRenderer() {
diff --git a/core/src/netwerkprog/game/util/tree/AbstractTree.java b/core/src/netwerkprog/game/util/tree/AbstractTree.java
index 910ab3c..7c7c9ee 100644
--- a/core/src/netwerkprog/game/util/tree/AbstractTree.java
+++ b/core/src/netwerkprog/game/util/tree/AbstractTree.java
@@ -1,19 +1,19 @@
 package netwerkprog.game.util.tree;
 
 public abstract class AbstractTree<E> implements Tree<E> {
-  @Override /** Inorder traversal from the root*/
+  @Override /* Inorder traversal from the root*/
   public void inorder() {
   }
 
-  @Override /** Postorder traversal from the root */
+  @Override /* Postorder traversal from the root */
   public void postorder() {
   }
 
-  @Override /** Preorder traversal from the root */
+  @Override /* Preorder traversal from the root */
   public void preorder() {
   }
 
-  @Override /** Return true if the tree is empty */
+  @Override /* Return true if the tree is empty */
   public boolean isEmpty() {
     return getSize() == 0;
   }