app/src/main/java/labbar/Board.java

@@ -7,8 +7,7 @@ public class Board {
     private String winner_id = null;
 
     public Optional<String> getWinnder() {
-        if (winner_id == null)
-            return Optional.empty();
+        if (winner_id == null) return Optional.empty();
         return Optional.of(winner_id);
     }
 
@@ -17,16 +16,21 @@ public class Board {
     }
 
     public void takePins(int pins) {
-        this.pins -= Math.min(this.pins, Math.min(2, pins));
+        this.pins -= Math.min(2, pins);
+        this.pins = Math.max(0, this.pins);
     }
 
-    public int alert(String userId, int pins) {
-        if (this.pins <= 0)
-            UserInterface.printMessage(String.format("%s picks %d and wins!", userId, pins));
-        else
-            UserInterface.printMessage(String.format(
-                    "%s picks %d pins.\n%d pins remaining.", userId, pins, this.pins));
-        return 0;
+    public void alert(String userId, int pins) {
+        if(this.pins <= 0) System.out.println(userId + String.format(" picks %d and wins!", pins));
+        else System.out.println(userId + " took " + pins + " pins.");
+    }
+
+    public void printState() {
+        printState(false);
+    }
+    public void printState(boolean lineBreak) {
+        System.out.println("There are " + this.pins + " pins left.");
+        if (lineBreak) System.out.println();
     }
 
     // GetPinsAmount

app/src/main/java/labbar/ComputerPlayer.java

@@ -8,8 +8,10 @@ public class ComputerPlayer extends Player {
     @Override
     int takePins(Board board) {
         int n = Math.min(
-                (int) (Math.random() * 2 + 1), // Random int between 1 and 2
-                board.getNoPins());
+                (int) (Math.random()*2 + 1), // Random int between 1 and 2
+                board.getNoPins()
+                );
+        System.out.println(n);
         board.takePins(n);
         board.alert(this.getUserId(), n);
         return n;

app/src/main/java/labbar/HumanPlayer.java

@@ -1,5 +1,7 @@
 package labbar;
 
+import javax.swing.JOptionPane;
+
 public class HumanPlayer extends Player {
     HumanPlayer(String userId) {
         super(userId);
@@ -7,10 +9,14 @@ public class HumanPlayer extends Player {
 
     @Override
     int takePins(Board board) {
-        int input = UserInterface.askForInt("How many pins do you want to take?");
-        if(input < 0) return input; // Propagate input
-        int i = Math.min(board.getNoPins(), Math.min(2, input)); // Clamp input
+        // Filter all non-digits from the input
+        String input = JOptionPane.showInputDialog("How many pins do you want to take?").chars()
+            .filter(Character::isDigit)
+            .collect(StringBuilder::new, StringBuilder::appendCodePoint, StringBuilder::append)
+            .toString();
 
+        
+        int i = Math.max(board.getNoPins(), Math.min(2, Integer.parseInt(input))); // "Should" never throw given input is sanitized
         board.takePins(i);
         board.alert(this.getUserId(), i);
         return i;

app/src/main/java/labbar/TakePinsGame.java

@@ -1,27 +1,18 @@
 package labbar;
-import java.util.ArrayList;
-import java.util.List;
 
 public class TakePinsGame {
-    static void abort(String message) {
-        System.out.println(message);
-        System.exit(0);
-    }
-
     public static void main(String[] args) {
         Board board = new Board();
         board.setUp(10);
-        // board.printState();
+        board.printState();
+        
+        Player player = new ComputerPlayer("Human");
+        Player cpu = new ComputerPlayer("Computer");
 
-        List<Player> players = new ArrayList<Player>();
-        players.add(new HumanPlayer("Human"));
-        players.add(new ComputerPlayer("Siri"));
-        players.add(new ComputerPlayer("Hal"));
-
-        if(players.size() < 2) abort("Not enough players");
-
-        for (int index = 0; board.getNoPins() > 0; index = (index + 1) % players.size()) {
-            if(players.get(index).takePins(board) < 0) abort("User aborted game");
+        for(boolean playerTurn = true; board.getNoPins() > 0; playerTurn = !playerTurn) {
+            if(playerTurn) player.takePins(board);
+            else cpu.takePins(board);
+            board.printState(true);
         }
     }
 }

app/src/main/java/labbar/UserInterface.java

@@ -1,27 +0,0 @@
-package labbar;
-
-import javax.swing.JOptionPane;
-
-
-public class UserInterface {
-    public static void printMessage(String message) {
-        JOptionPane.showMessageDialog(null, message);
-    }
-
-    public static int askForInt(String message) {
-        String input = JOptionPane.showInputDialog(message);
-        if (input == null) return -2;
-
-        // Shadow input
-        input = input.chars()
-            .filter(Character::isDigit)
-            .collect(StringBuilder::new, StringBuilder::appendCodePoint, StringBuilder::append)
-            .toString();
-
-        try {
-            return Integer.parseInt(input);
-        } catch (NumberFormatException e) {
-            return -1;
-        }
-    }
-}

app/src/test/java/labbar/PlayerTests.java

@@ -7,15 +7,17 @@ class PlayerTests{
     @Test void fullCpuGameTest() {
         Board b = new Board();
 
-        b.setUp(10);
+        // Unreasonable amount of pins
+        b.setUp(500);
         
         // Two computer players
-        Player player_a = new ComputerPlayer("Cortana");
-        Player player_b = new ComputerPlayer("Alexa");
+        Player player_a = new ComputerPlayer("Siri");
+        Player player_b = new ComputerPlayer("Hal");
 
         for(boolean playerTurn = true; b.getNoPins() > 0; playerTurn = !playerTurn) {
             if(playerTurn)  player_a.takePins(b);
             else            player_b.takePins(b);
+            b.printState();
         }
 
         assertEquals(0, b.getNoPins());