diff --git a/pom.xml b/pom.xml
index e1cfeca..a9094be 100644
--- a/pom.xml
+++ b/pom.xml
@@ -11,7 +11,7 @@
         <dependency>
             <groupId>org.junit.jupiter</groupId>
             <artifactId>junit-jupiter</artifactId>
-            <version>RELEASE</version>
+            <version>5.9.0</version>
             <scope>test</scope>
         </dependency>
         <dependency>
diff --git a/src/main/java/mau/mau/Dealer.java b/src/main/java/mau/mau/Dealer.java
index eea373b..0c649da 100644
--- a/src/main/java/mau/mau/Dealer.java
+++ b/src/main/java/mau/mau/Dealer.java
@@ -7,7 +7,7 @@ import java.util.Collections;
 import java.util.List;
 
 public class Dealer {
-    private Deck deck;
+    private final Deck deck;
 
     public Dealer(Deck deck) {
         this.deck = deck;
diff --git a/src/main/java/mau/mau/TYPENUM.java b/src/main/java/mau/mau/TYPENUM.java
index 09f4111..6807d8a 100644
--- a/src/main/java/mau/mau/TYPENUM.java
+++ b/src/main/java/mau/mau/TYPENUM.java
@@ -1,5 +1,5 @@
 package mau.mau;
 
 public enum TYPENUM {
-    SPADES, HEARTS, DIAMONDS, CLUBS, JOKER;
+    SPADES, HEARTS, DIAMONDS, CLUBS, JOKER
 }
diff --git a/src/main/java/mau/mau/TurnTable.java b/src/main/java/mau/mau/TurnTable.java
index 2feb3d2..75a9835 100644
--- a/src/main/java/mau/mau/TurnTable.java
+++ b/src/main/java/mau/mau/TurnTable.java
@@ -5,7 +5,7 @@ import mau.mau.players.Player;
 import java.util.List;
 
 public class TurnTable {
-    private List<Player> players;
+    private final List<Player> players;
     private int currentPlayerIndex;
     private int direction;
 
diff --git a/src/main/java/mau/mau/players/Bot.java b/src/main/java/mau/mau/players/Bot.java
index 27eed25..a8841e1 100644
--- a/src/main/java/mau/mau/players/Bot.java
+++ b/src/main/java/mau/mau/players/Bot.java
@@ -4,13 +4,12 @@ import mau.mau.*;
 
 import java.util.HashMap;
 import java.util.List;
-import java.util.Scanner;
 
 public class Bot extends Player {
 
     private static int nameIndex = 0;
-    private static String JSON = "src/main/resources/languages/en.json";
-    private static String JSON_KEY = "botnames";
+    private static final String JSON = "src/main/resources/languages/en.json";
+    private static final String JSON_KEY = "bot-names";
 
     public Bot(Dealer dealer) {
         super(dealer);
@@ -82,7 +81,7 @@ public class Bot extends Player {
         try {
             return JSONderulo.getJSONArrayFromJSONFile(JSON, JSON_KEY).getString(nameIndex++);
         } catch (Exception e) {
-            System.out.println("Error reading botnames from JSON file");
+            System.out.println("Error reading bot-names from JSON file");
             return "Koet " + nameIndex++;
         }
     }
diff --git a/src/main/java/mau/mau/players/Player.java b/src/main/java/mau/mau/players/Player.java
index 5694c11..812a58f 100644
--- a/src/main/java/mau/mau/players/Player.java
+++ b/src/main/java/mau/mau/players/Player.java
@@ -8,9 +8,9 @@ import java.util.List;
 
 public abstract class Player {
 
-    private String name;
+    private final String name;
     private List<Card> hand;
-    private Dealer dealer;
+    private final Dealer dealer;
 
     public Player(Dealer dealer) {
         this.dealer = dealer;
@@ -21,8 +21,8 @@ public abstract class Player {
         return hand;
     }
 
-    public List<Card> setHand(List<Card> hand) {
-        return this.hand = hand;
+    public void setHand(List<Card> hand) {
+        this.hand = hand;
     }
 
     public Boolean handIsEmpty() {
diff --git a/src/main/resources/diagrams/SequenceDiagram.puml b/src/main/resources/diagrams/SequenceDiagram.puml
index 6ad1794..d005741 100644
--- a/src/main/resources/diagrams/SequenceDiagram.puml
+++ b/src/main/resources/diagrams/SequenceDiagram.puml
@@ -20,7 +20,7 @@ loop until someone wins
         else draw
             User -> Player: draw()
         end
-    else bot's turn
+    else bots turn
         alt play
             Bot -> Player: play(card)
             Game <-- Player: playedCard
diff --git a/src/main/resources/languages/en.json b/src/main/resources/languages/en.json
index 0408084..d84a42c 100644
--- a/src/main/resources/languages/en.json
+++ b/src/main/resources/languages/en.json
@@ -1,5 +1,5 @@
 {
-  "botnames": [
+  "bot-names": [
     "Jordan",
     "MaarKoet",
     "El Tigre"
diff --git a/src/test/java/mau/mau/CardHandlerTest.java b/src/test/java/mau/mau/CardHandlerTest.java
index bf43e97..04a1591 100644
--- a/src/test/java/mau/mau/CardHandlerTest.java
+++ b/src/test/java/mau/mau/CardHandlerTest.java
@@ -15,13 +15,12 @@ public class CardHandlerTest {
     private CardHandler sut;
     private TurnTable turnTable;
     private List<Player> players;
-    private Dealer dealer;
     private Bot bot1, bot2, bot3;
 
     @BeforeEach
     public void setUp() {
         //Arrange
-        dealer = new Dealer(new Deck());
+        Dealer dealer = new Dealer(new Deck());
         sut = new CardHandler();
         players = new ArrayList<>();
         turnTable = new TurnTable(players);
diff --git a/src/test/java/mau/mau/DealerTest.java b/src/test/java/mau/mau/DealerTest.java
index 49b8d37..72a90dc 100644
--- a/src/test/java/mau/mau/DealerTest.java
+++ b/src/test/java/mau/mau/DealerTest.java
@@ -1,8 +1,4 @@
 package mau.mau;
 
-import org.junit.jupiter.api.Test;
-
-import static org.junit.jupiter.api.Assertions.assertTrue;
-
 public class DealerTest {
 }
diff --git a/src/test/java/mau/mau/RefereeTest.java b/src/test/java/mau/mau/RefereeTest.java
index 29b1845..b6cdbd7 100644
--- a/src/test/java/mau/mau/RefereeTest.java
+++ b/src/test/java/mau/mau/RefereeTest.java
@@ -99,7 +99,7 @@ public class RefereeTest {
 
 
     @Test
-    public void isAceOfSpadesValidEndcardTest(){
+    public void isAceOfSpadesValidEndCardTest(){
         //Arrange
         Card testCardOne = new Card(TYPENUM.SPADES, VALUENUM.ACE);
         Card testCurrentCard = new Card(TYPENUM.HEARTS, VALUENUM.ACE);
@@ -112,7 +112,7 @@ public class RefereeTest {
     }
 
     @Test
-    public void isThreeOfHeartsValidEndcardTest(){
+    public void isThreeOfHeartsValidEndCardTest(){
         //Arrange
         Card testCardOne = new Card(TYPENUM.HEARTS, VALUENUM.THREE);
         Card testCurrentCard = new Card(TYPENUM.HEARTS, VALUENUM.ACE);
diff --git a/src/test/java/mau/mau/players/BotTest.java b/src/test/java/mau/mau/players/BotTest.java
index 3f7fddf..8a2f091 100644
--- a/src/test/java/mau/mau/players/BotTest.java
+++ b/src/test/java/mau/mau/players/BotTest.java
@@ -12,14 +12,12 @@ import static org.junit.jupiter.api.Assertions.*;
 public class BotTest {
 
     private Bot sut;
-    private Dealer dealer;
-    private Deck deck;
     private List<Card> hand;
 
     @BeforeEach
     public void setUp() {
-        deck = new Deck();
-        dealer = new Dealer(deck);
+        Deck deck = new Deck();
+        Dealer dealer = new Dealer(deck);
         sut = new Bot(dealer);
         hand = new ArrayList<>();
     }