Added setCellState to class Board with test

src/main/java/Game/TicTacToe/Board.java

@@ -34,6 +34,18 @@ public class Board {
         }
     }
 
+    public void setCellState(int cell, boolean cross) {
+        if (cell <= 9 && cell >= 1) {
+            if (this.states[cell-1] != State.EMPTY) {
+                return;
+            }
+            if (cross) {
+                this.states[cell-1] = State.CROSS;
+            } else {
+                this.states[cell-1] = State.CIRCLE;
+            }
+        }
+    }
 
 
     /*

src/test/java/Game/TicTacToe/BoardTest.java

@@ -5,6 +5,8 @@ import org.junit.jupiter.api.AfterEach;
 import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.Test;
 
+import java.util.Arrays;
+
 import static org.junit.jupiter.api.Assertions.*;
 
 class BoardTest {
@@ -34,6 +36,17 @@ class BoardTest {
         }
     }
 
+    @Test
+    void setCellState() {
+        Board.State[] lastBoard = Arrays.copyOf(board.getStates(), board.getStates().length);
+        board.setCellState(1, true);
+        assertFalse(Arrays.equals(lastBoard, board.getStates()));
+        assertEquals(board.getStates()[0], Board.State.CROSS);
+        board.setCellState(1, false);
+        assertEquals(board.getStates()[0], Board.State.CROSS);
+        board.setCellState(2, false);
+        assertEquals(board.getStates()[1], Board.State.CIRCLE);
+    }
 
     @SuppressWarnings("AssertBetweenInconvertibleTypes")
     @Test