Added Gameinterface with TTT class and printTest

src/main/java/Game/Game.java

@@ -0,0 +1,8 @@
+package Game;
+
+public interface Game {
+    public abstract void print();
+
+
+
+}

src/main/java/Game/Tictactoe.java

@@ -0,0 +1,18 @@
+package Game;
+
+import java.util.ArrayList;
+
+public class Tictactoe implements Game {
+    private ArrayList<String> outputBuffer = new ArrayList<String>();
+
+    @Override
+    public void print() {
+        for (int i = 0; i < outputBuffer.size(); i++) {
+            System.out.println(outputBuffer.get(i)); 
+        }
+    }
+
+    void setOutputBuffer(ArrayList<String> outputBuffer){
+        this.outputBuffer = outputBuffer;
+    }
+}

src/test/java/Game/TictactoeTest.java

@@ -0,0 +1,44 @@
+package Game;
+
+import org.junit.Rule;
+import org.junit.contrib.java.lang.system.SystemOutRule;
+import org.junit.jupiter.api.AfterEach;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+
+import java.io.ByteArrayOutputStream;
+import java.io.PrintStream;
+import java.util.ArrayList;
+
+import static org.junit.jupiter.api.Assertions.*;
+
+class TictactoeTest {
+
+    private final ByteArrayOutputStream outContent = new ByteArrayOutputStream();
+    private final PrintStream originalOut = System.out;
+
+    Tictactoe ttt;
+
+
+    @BeforeEach
+    void setUp() {
+        ttt = new Tictactoe();
+        System.setOut(new PrintStream(outContent));
+    }
+
+    @AfterEach
+    void tearDown() {
+        System.setOut(originalOut);
+    }
+
+    @Test
+    public void testPrint() {
+        ArrayList<String> testOB = new ArrayList<String>();
+        testOB.add("Hello");
+        testOB.add("World");
+        testOB.add("!!!");
+        ttt.setOutputBuffer(testOB);
+        ttt.print();
+        assertEquals("Hello\nWorld\n!!!\n", outContent.toString().replaceAll("\r", ""));
+    }
+}