How to make tic toc game in java : Notepad (Source Code)

Introduction

Tic-tac-toe is a very popular paper and pencil game, programmers often make this game as a beginner for practice. As a starter in programming, we feel very happy after completing our first tic-tac-toe game and we enjoy a lot by playing our own made game with our friends and family members. 

In this blog, we will learn how to create tic-tac-toe game in java. 

Tic-Tac_Toe

First, we need to understand the logic of the game. In this game, we need a 3 x 3 grid pattern like fig 1 and in the console, it will look like fig 2, the player who places three of their choices in vertical, horizontal, or diagonal will be the winner of the game.

      

                                            (fig 1)                                                  (fig 2)

Following are some steps we need to do, in order to create a tic-toc-toe game.

1) Display Pattern

First, we need to display a pattern to the user. For this, we will create a class and then create a static method "display" in it. This method will display a pattern for us.

import java.util.Scanner;
public class Tictoc {
  char tictoc[][]=new char[3][3];
  //Display Fuction
  public static void display(char tictoc[][]) {
  for(int i=0;i<3;i++)
  {
   for(int j=0;j<3;j++)
   {
    System.out.print(tictoc[i][j]+" ");
   }
   System.out.println();
  }
 }
}

In order to show patter. We will first create "Tictoc" class object in "main" method and call the static display method to display patter.

Tictoc game=new Tictoc();

int counter=0;
for(int i=0 ; i<3; i++)
{
  for(int j=0 ; j<3 ; j++)
  {
    game.tictoc[i][j]=Character.forDigit(++counter,10);
  }
}
//Display Board
display(game.tictoc);

2) Take marker input from the user

In the above section, we successfully display pattern to the user (like fig a). Now it's time to take user choice. First, user one will enter his/her choice, the user can pick between 0 and 8, if user select 1 then in "replace" method we will change second index of tictoc[][] array to user one symbol "X" and with "display" method we will show updated pattern like fig b.

                                                  (fig a)                                        (fig b)

  char input;
  for(int i=0;i<4;i++)
  {
   System.out.print(user1+" Turn: ");
   input=in.next().charAt(0);
   replace(game.tictoc,input,user1mark);
   display(game.tictoc);
   System.out.print(user2+" Turn: ");
   input=in.next().charAt(0);
   replace(game.tictoc,input,user2mark);
   display(game.tictoc);
  }
  System.out.print("User "+user1+": ");
  input=in.next().charAt(0);
  replace(game.tictoc,input,user1mark);
  display(game.tictoc);
    

3) Final step is to check the winner

Now, the last step remaining is to check the winner. Here we will check, does any player place three of their choices in vertical, horizontal, or diagonal. If yes then we will declare this player winner, otherwise, we will display draw message to the user.

if(game.checkForWin())
    System.out.print("We have a Winner");
else
    System.out.print("Match is Draw");

That's it. Following is the complete source code of the game. Enjoy

Source Code

import java.util.Scanner;
public class Tictoc {
  char tictoc[][]=new char[3][3];
 //Display Fuction
 public static void display(char tictoc[][]) {
  for(int i=0;i<3;i++)
  {
   for(int j=0;j<3;j++)
   {
    System.out.print(tictoc[i][j]+" ");
   }
   System.out.println();
  }
 }
 //Replace Function
 static void replace(char arr[][], char find, char replace) {
    for (int i = 0; i < 3 ; i++) 
 {
  for(int j=0 ; j < 3 ; j++)
  {
   if (arr[i][j] == find) 
   {
    arr[i][j] = replace;
    return;
   }
        }
    }
}

 //check for win function
 public boolean checkForWin() {
  return (checkForRow() || checkForColomn() || checkForDiagnol());
 }
 
  //This function check row, colomn, diagnol for checkForRow, checForDiagnol, checkForColomn function
 public boolean check(char c1,char c2, char c3)
 {
  return((c1==c2) && (c2==c3));
 }
 //check for row function
 public boolean checkForRow() {
  for(int i=0; i<3; i++)
  {
   if(check(tictoc[i][0],tictoc[i][1],tictoc[i][2])==true)
    return true;
  }
  return false;
 }
 //check for colomn function
 public boolean checkForColomn() {
  for(int i=0; i<3; i++)
  {
   if(check(tictoc[0][i],tictoc[1][i],tictoc[2][0])==true)
    return true;
  }
  return false;
 }
 //check for Diagnol function
 public boolean checkForDiagnol()
 {
  return((check(tictoc[0][0],tictoc[1][1],tictoc[2][2])==true) || (check(tictoc[0][2],tictoc[1][1],tictoc[2][0])==true));
 }
 
 //main Function
 public static void main(String[] args) {
  Tictoc game=new Tictoc();
  Scanner in=new Scanner(System.in);
  //Select Player 
  String user1,user2;
  char user1mark,user2mark;
  System.out.print("Enter Player one Name: ");
  user1=in.nextLine();
  System.out.print("Enter Player two Name: ");
  user2=in.nextLine();
  //Mark Selection
  System.out.println(user1+" Select Your Marker (O or X): ");
  //System.out.println(name2+" Select Your Marker (O or X): ");
  user1mark=in.next().charAt(0);
  while(user1mark != 'X' && user1mark != 'x' && user1mark != 'O' && user1mark != 'o')
  {
   System.out.print("Invalid Input (Select O or X): ");
   user1mark=in.next().charAt(0);
  }
  if(user1mark=='X' || user1mark=='x')
   user2mark='O';
  else
   user2mark='X';
  //initialize board
  int counter=0;
  for(int i=0 ; i<3; i++)
  {
   for(int j=0 ; j<3 ; j++)
   {
    game.tictoc[i][j]=Character.forDigit(++counter,10);
   }
  }
  //Display Board
  display(game.tictoc);
  
  //Play

  char input;
  for(int i=0;i<4;i++)
  {
   System.out.print(user1+" Turn: ");
   input=in.next().charAt(0);
   replace(game.tictoc,input,user1mark);
   display(game.tictoc);
   System.out.print(user2+" Turn: ");
   input=in.next().charAt(0);
   replace(game.tictoc,input,user2mark);
   display(game.tictoc);
  }
   System.out.print("User "+user1+": ");
   input=in.next().charAt(0);
   replace(game.tictoc,input,user1mark);
   display(game.tictoc);
   //Check For Win or Tie

   if(game.checkForWin())
    System.out.print("We have a Winner");
   else
    System.out.print("Match is Draw");
 }
}