TicTacToe.java

/** Java lvl 1. Homework 4
* @author Artur
* @version 17.10.2021
*/

import java.util.Random;
import java.util.Scanner;

class TicTacToe {
    final char SIGN_X = 'X'; 
    final char SIGN_O = 'O';
    final char SIGN_EMPTY = '.';
    char[] [] table;
    Random random;
    Scanner scanner;    
    
    public static void main(String[] args) {
        new TicTacToe().game();
    }

    TicTacToe() {
        // инициализация полей
        table = new char [3] [3];
        random = new Random();
        scanner = new Scanner(System.in);
    }

    void game() {
        initTable();
        while (true) {
            printTable();
            turnHuman();
            if (isWin(SIGN_X)) {
                System.out.println("you win");
                break;
            }
            if (isTableFull()) {
                System.out.println("Sorry, DRAW...");
                break;
            }
            turnAi();
            if (isWin(SIGN_O)) {
                System.out.println("Ai win");
                break;
            }
            if (isTableFull()) {
                System.out.println("Sorry, DRAW...");
                break;
            }
        }
        printTable();
    }

    void initTable() {
        for (int i = 0; i < 3; i++) {
            for (int j = 0; j < 3; j++) {
                table[i][j] = SIGN_EMPTY;
            }
        }
    }

    void printTable() {
        for (int i = 0; i < 3; i++) {
            for (int j = 0; j < 3; j++) {
                System.out.print(table[j][i] + " ");
            }
            System.out.println();
        }
    }

    void turnHuman() {
        int x, y;
        do {
            System.out.print("Enter [1...3] x y: ");
            x = scanner.nextInt() - 1;
            y = scanner.nextInt() - 1;
        } while (!isCellValid(x, y));
        table[x][y] = SIGN_X;
    }

    void turnAi() {
        int x, y;
        do {
            x = random.nextInt(3);
            y = random.nextInt(3);
        } while (!isCellValid(x, y));
        table[x][y] = SIGN_O;
    }

    boolean isCellValid(int x, int y) {
        if ( x < 0 || x > 2 || y < 0 || y > 2) {
            return false;
        }
        return table[x][y] == SIGN_EMPTY;
    }

    boolean isWin(char ch) {
        boolean toright = true; 
        for (int i = 0; i < 2; i++) { 
            toright = toright & (table[i][i] == ch); 
        }
            if (toright) return true;	
        return false; 
        //x
        // if (table[0][0] == ch && table[1][0] == ch && table [2][0] == ch) return true;
        // if (table[0][1] == ch && table[1][1] == ch && table [2][1] == ch) return true;
        // if (table[0][2] == ch && table[1][2] == ch && table [2][2] == ch) return true;
        // //y
        // if (table[0][0] == ch && table[0][1] == ch && table [0][2] == ch) return true;
        // if (table[1][0] == ch && table[1][1] == ch && table [1][2] == ch) return true;
        // if (table[2][0] == ch && table[2][1] == ch && table [2][2] == ch) return true;
        // //d
        // if (table[0][0] == ch && table[1][1] == ch && table [2][2] == ch) return true;
        // if (table[2][0] == ch && table[1][1] == ch && table [0][2] == ch) return true;
        // return false;
    }

    boolean isTableFull() {
        for (int i = 0; i < 3; i++) {
            for (int j = 0; j < 3; j++) {
                if (table[i][j] == SIGN_EMPTY) {
                    return false;
                }
            }
        }
        return true;
    }
}