<%@ page language="java" import ="java.util.*" import="java.math.*" %>
TicTacToe
TicTacToe
<% // Declare and initialize game state variables
char[][] tiles; // game board
String winner; // game winner
// Initialize state if it is not already present in the session
tiles = (char[][]) session.getAttribute("tiles");
winner = (String) session.getAttribute("winner");
if (tiles == null || winner == null) {
tiles = new char[3][3];
for (int r=0; r<3; r++)
for (int c=0; c<3; c++)
tiles[r][c] = ' ';
winner = new String("");
}
%>
<% // Check for a "Reset" button click
if (request.getParameter("reset") != null) {
for (int r=0; r<3; r++)
for (int c=0; c<3; c++)
tiles[r][c] = ' ';
winner = new String("");
}
%>
<% // Check for a game button click
boolean didX = false;
if (winner.equals("")) {
for (int r=0; r<3; r++) {
for (int c=0; c<3; c++) {
if (request.getParameter("B" + r + c) != null && tiles[r][c] == ' ') {
tiles[r][c] = 'X';
didX = true;
}
}
}
}
if (didX) {
// see if X won
for (int r=0; r<3; r++) {
if (tiles[r][0]=='X' && tiles[r][1]=='X' && tiles[r][2] == 'X') {
winner = new String("X");
}
}
for (int c=0; c<3; c++) {
if (tiles[0][c]=='X' && tiles[1][c]=='X' && tiles[2][c] == 'X') {
winner = new String("X");
}
}
if (tiles[0][0]=='X' && tiles[1][1]=='X' && tiles[2][2] == 'X') {
winner = new String("X");
}
if (tiles[0][2]=='X' && tiles[1][1]=='X' && tiles[2][0] == 'X') {
winner = new String("X");
}
}
// play O
if (didX && winner.equals("")) {
boolean playable = false;
for (int r=0; r<3; r++) for (int c=0; c<3; c++) {
if (tiles[r][c] == ' ') {
playable = true;
}
}
if (playable) {
boolean didO = false;
while (!didO) {
int r = (int) (Math.random() * 3);
int c = (int) (Math.random() * 3);
if (tiles[r][c] == ' ') {
tiles[r][c] = 'O';
didO = true;
}
}
// check for "O" win
for (int r=0; r<3; r++) {
if (tiles[r][0]=='O' && tiles[r][1]=='O' && tiles[r][2] == 'O') {
winner = new String("O");
}
}
for (int c=0; c<3; c++) {
if (tiles[0][c]=='O' && tiles[1][c]=='O' && tiles[2][c] == 'O') {
winner = new String("O");
}
}
if (tiles[0][0]=='O' && tiles[1][1]=='O' && tiles[2][2] == 'O') {
winner = new String("O");
}
if (tiles[0][2]=='O' && tiles[1][1]=='O' && tiles[2][0] == 'O') {
winner = new String("O");
}
}
}
%>
<% // Save game state as session attributes
session.setAttribute("tiles", tiles);
session.setAttribute("winner", winner);
%>