Question

This is my code for a TicTacToe game. However, I don't know how to write JUnit tests. Please help me with my JUnit Tests. I will post below what I have so far.

package cs145TicTacToe;
import java.util.Scanner;

/**
* A multiplayer Tic Tac Toe game
*/
public class TicTacToe {

   private char currentPlayer;
   private char[][] board;
   private char winner;
  
   /**
   * Default constructor
   * Initializes the board to be 3 by 3 and to have spaces
   * Initializes the current player to an X
   * Initializes the winner to be empty
   */
   public TicTacToe() {
       board = new char [3][3];
       currentPlayer = 'X';
       winner = ' ';
      
       for(int row = 0; row < 3; row++) {
           for(int col = 0; col < 3; col++) {
               board[row][col] = ' ';
           }
       }
   }
  
   /**
   * Returns if the currentPlayer is an X or an O
   * @return the currentPlayer
   */
   public char getCurrentPlayer() {
       return currentPlayer;
   }
  
   /**
   * Returns who the winner is  
   * @return the winner
   */
   public char getWinner() {
       return winner;
   }
  
   /**
   * Determines who's turn it is and if the space they picked is available on the board or not
   * @param row represents the row of the board
   * @param col represents the column of the board
   * @return true if the selected square is available, false if it isn't
   */
   public boolean takeTurn(int row, int col) {  
       if(board[row][col] == ' ') {
           board[row][col] = currentPlayer;
           checkForWinner();
           if(checkForWinner() == true) {
               System.out.println(toString());
               System.out.println(getCurrentPlayer() + " is the winner!");
           }
           //enter if for check for winner == true
           else if(currentPlayer == 'X') {
               currentPlayer = 'O';
           }
           else {
               currentPlayer = 'X';
           }
          
           return true;
       }
       else {
           System.out.println("This spot is taken. Try entering a different spot.");
           return false;
       }
          
   }
  
   /**
   * Checks if a player has made it three in a row
   * @return true if a player won, false if no player has won
   */
   public boolean checkForWinner() {
      
       for (int row = 0; row < 3; row++) {
           if(board[row][0] == currentPlayer && board[row][1] == currentPlayer && board[row][2] == currentPlayer) {
               winner = currentPlayer;
               return true;
           }
       }
       for(int col = 0; col < 3; col++) {
           if(board[0][col] == currentPlayer && board[1][col] == currentPlayer && board[2][col] == currentPlayer) {
               winner = currentPlayer;
               return true;
           }
       }  
       if((board[0][0] == currentPlayer && board[1][1] == currentPlayer && board[2][2] == currentPlayer) || (board[0][2] == currentPlayer && board[1][1] == currentPlayer && board[2][0] == currentPlayer)) {
               winner = currentPlayer;
               return true;
       }  
          
       return false;
   }
  
   /**
   * Represents the board and players in string form
   * @return the board with X's and O's
   */
   @Override
   public String toString() {
      
       String output = "| " + board[0][0] + " | " + board[1][0] + " | " + board[2][0] + " | \n";
       output += "-------------- \n";
       output += "| " + board[0][1] + " | " + board[1][1] + " | " + board[2][1] + " | \n";
       output += "-------------- \n";
       output += "| " + board[0][2] + " | " + board[1][2] + " | " + board[2][2] + " | \n";
      
       return output;
   }
  
   /**
   * Represents the main function and interacts with the user(s) and calls the methods
   * @param args
   */
   public static void main(String[] args) {
       // TODO Auto-generated method stub
       int userRow;
       int userCol;
       int userAnswer;
       boolean keepPlaying = true;
       boolean gameWon = false;
       TicTacToe object = new TicTacToe();
       Scanner keyboardIn = new Scanner(System.in);
      
       System.out.println("Welcome to Tic Tac Toe");
       //verify user input
      
       do {
           do {
       System.out.println("Current Player: " + object.getCurrentPlayer());
       System.out.println(object.toString());
       System.out.println("Enter a column:");
       userRow = keyboardIn.nextInt() - 1;
       System.out.println("Enter a row:");
       userCol = keyboardIn.nextInt() - 1;
       object.takeTurn(userRow, userCol);
       gameWon = object.checkForWinner();
      
           }while(gameWon == false);
          
           System.out.println("Do you want to play again? Enter 1 for yes or 2 for no.");
           userAnswer = keyboardIn.nextInt();
           if(userAnswer == 1) {
               //call constructor to clear board
               keepPlaying = true;
              
           }
           else {
               System.out.println("Thanks for playing!");
               keepPlaying = false;
           }
      
       }
       while(keepPlaying == true);
       keyboardIn.close();
   }
      
}

What I currently have for my JUnit tests:

package cs145TicTacToe;

import static org.junit.jupiter.api.Assertions.*;

import org.junit.jupiter.api.BeforeEach;
import org.junit.jupiter.api.Test;

/**
*
*/
class TicTacToeTest {
  
   TicTacToe game;
  

   /**
   * @throws java.lang.Exception
   */
   @BeforeEach
   void setUp() throws Exception {
       game = new TicTacToe();
       game.getCurrentPlayer();
   }

   /**
   * Test method for {@link cs145TicTacToe.TicTacToe#TicTacToe()}.
   */
   @Test
   void testTicTacToe() {
       assertEquals('X', game.getCurrentPlayer());
       assertEquals(' ', game.getWinner());
       //more with board?
   }

   /**
   * Tests to make sure the program is returning the correct current player
   * Test method for {@link cs145TicTacToe.TicTacToe#getCurrentPlayer()}.
   */
   @Test
   void testGetCurrentPlayer() {
       assertEquals('X', game.getCurrentPlayer());
   }

   /**
   * Tests to make sure the program is returning the correct winner
   * Test method for {@link cs145TicTacToe.TicTacToe#getWinner()}.
   */
   @Test
   void testGetWinner() {
       fail("Not yet implemented");
   }

   /**
   * Test method for {@link cs145TicTacToe.TicTacToe#takeTurn(int, int)}.
   */
   @Test
   void testTakeTurn() {
       fail("Not yet implemented");
   }

   /**
   * Tests the checkForWinner() method
   * Test method for {@link cs145TicTacToe.TicTacToe#checkForWinner()}.
   */
   @Test
   void testCheckForWinner() {
       fail("Not yet implemented");
   }

   /**
   * Tests the toString() method and prints out the board
   * Test method for {@link cs145TicTacToe.TicTacToe#toString()}.
   */
   @Test
   void testToString() {
       assertEquals("| | | | \n" +
               "-------------- \n" +
               "| | | | \n" +
               "-------------- \n" +
               "| | | | \n", game.toString());
   }

}

im just wondering if you can look at my code that I provided and make JUnit tests out of the methods. All I need is the JUnit tests

Answer 1

/**
*
*/
public class TicTacToeTest {
  
   TicTacToe game;  

   /**
   * @throws java.lang.Exception
   */
   @BeforeEach
   void setUp() throws Exception {
       game = new TicTacToe();
       game.getCurrentPlayer();
   }

   /**
   * Test method for {@link cs145TicTacToe.TicTacToe#TicTacToe()}.
   */
   @Test
   void testTicTacToe() {
       assertEquals('X', game.getCurrentPlayer());
       assertEquals(' ', game.getWinner());
       //more with board?
       assertFalse(game.checkForWinner());
   }

   /**
   * Tests to make sure the program is returning the correct current player
   * Test method for {@link cs145TicTacToe.TicTacToe#getCurrentPlayer()}.
   */
   @Test
   void testGetCurrentPlayer() {
       assertEquals('X', game.getCurrentPlayer());
       game.takeTurn(0, 0);
       assertEquals('O', game.getCurrentPlayer());
       game.takeTurn(0, 0);
       assertEquals('O', game.getCurrentPlayer());
       game.takeTurn(0, 1);
       assertEquals('X', game.getCurrentPlayer());
   }

   /**
   * Tests to make sure the program is returning the correct winner
   * Test method for {@link cs145TicTacToe.TicTacToe#getWinner()}.
   */
   @Test
   void testGetWinner() {
       game.takeTurn(0, 0);
       game.takeTurn(2, 0);
       game.takeTurn(0, 1);
       game.takeTurn(2, 1);
       game.takeTurn(0, 2);
       assertEquals('X', game.getWinner());
   }

   /**
   * Test method for {@link cs145TicTacToe.TicTacToe#takeTurn(int, int)}.
   */
   @Test
   void testTakeTurn() {
       game.takeTurn(0, 0);
       assertEquals('O', game.getCurrentPlayer());
       game.takeTurn(0, 0);
       assertEquals('O', game.getCurrentPlayer());
       game.takeTurn(0, 1);
       assertEquals('X', game.getCurrentPlayer());
   }

   /**
   * Tests the checkForWinner() method
   * Test method for {@link cs145TicTacToe.TicTacToe#checkForWinner()}.
   */
   @Test
   void testCheckForWinner() {
       game.takeTurn(0, 0);
       game.takeTurn(2, 0);
       game.takeTurn(1, 1);
       game.takeTurn(2, 1);
       game.takeTurn(2, 2);
       assertTrue(game.checkForWinner());
   }

   /**
   * Tests the toString() method and prints out the board
   * Test method for {@link cs145TicTacToe.TicTacToe#toString()}.
   */
   @Test
   void testToString() {       
       assertEquals("|   |   |   | \n" +
               "-------------- \n" +
               "|   |   |   | \n" +
               "-------------- \n" +
               "|   |   |   | \n", game.toString());
   }


}

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