// Internet Explorer users, look here: http://krijnhoetmer.nl/stuff/html/bug-internet-explorer-submit-button/
import java.io.*;
import javax.servlet.*;
import javax.servlet.http.*;
public class TicTacToe extends HttpServlet {
public void init() {
ServletContext c = getServletContext();
Integer[][] board = new Integer[3][3];
for (int i = 0; i<3; i++)
for (int j = 0; j<3; j++)
board[i][j] = new Integer(0);
c.setAttribute("board", board);
c.setAttribute("players", new Integer(0));
c.setAttribute("winner", new Integer(0));
c.setAttribute("next", new Integer(1));
c.setAttribute("free", new Integer(9));
}
public void doPost(HttpServletRequest request,
HttpServletResponse response)
throws IOException, ServletException {
doGet(request, response);
}
public void doGet(HttpServletRequest request,
HttpServletResponse response)
throws IOException, ServletException {
boolean post = request.getMethod().equals("POST");
ServletContext c = getServletContext();
Integer[][] board;
int next;
int winner;
int player;
int free;
synchronized(c) {
if (post && request.getParameter("reset")!=null) {
init();
for (int p = 1; p<=2; p++) {
HttpSession s = (HttpSession)c.getAttribute("player"+p);
if (s!=null) {
try {
s.invalidate();
} catch (IllegalStateException e) {}
}
}
PrintWriter out = response.getWriter();
out.print("TicTacToe");
out.print("Service is reset!");
out.print("");
out.print("");
return;
}
board = (Integer[][])c.getAttribute("board");
next = ((Integer)c.getAttribute("next")).intValue();
winner = ((Integer)c.getAttribute("winner")).intValue();
free = ((Integer)c.getAttribute("free")).intValue();
HttpSession ses = request.getSession(false);
if (ses==null) {
ses = request.getSession(true);
ses.setMaxInactiveInterval(60);
ses.setAttribute("invalid", null);
int players = ((Integer)c.getAttribute("players")).intValue();
if (players<2) {
player = ++players;
c.setAttribute("players", new Integer(players));
c.setAttribute("player"+player, ses);
ses.setAttribute("player", new Integer(player));
} else{
response.sendError(HttpServletResponse.SC_SERVICE_UNAVAILABLE, "Too many users!");
return;
}
} else {
player = ((Integer)ses.getAttribute("player")).intValue();
String move = request.getParameter("move");
if (post && move!=null && next==player && winner==0) {
int i = move.charAt(0)-'0';
int j = move.charAt(1)-'0';
if (board[i][j]==0) {
board[i][j] = new Integer(player);
if (next==1)
next = 2;
else
next = 1;
c.setAttribute("next", new Integer(next));
for (int p = 1; p<=2; p++) {
if ((board[0][0]==p && board[0][1]==p && board[0][2]==p) ||
(board[1][0]==p && board[1][1]==p && board[1][2]==p) ||
(board[2][0]==p && board[2][1]==p && board[2][2]==p) ||
(board[0][0]==p && board[1][0]==p && board[2][0]==p) ||
(board[0][1]==p && board[1][1]==p && board[2][1]==p) ||
(board[0][2]==p && board[1][2]==p && board[2][2]==p) ||
(board[0][0]==p && board[1][1]==p && board[2][2]==p) ||
(board[2][0]==p && board[1][1]==p && board[0][2]==p)) {
winner = p;
c.setAttribute("winner", new Integer(p));
}
}
c.setAttribute("free", new Integer(--free));
}
}
}
}
boolean me = next==player;
response.setDateHeader("Expires", 0);
response.setHeader("Cache-Control",
"no-store, no-cache, must-revalidate");
response.setHeader("Pragma", "no-cache");
PrintWriter out = response.getWriter();
out.print("TicTacToe");
if (me || winner!=0)
out.print("");
else
out.print("");
out.print("Player "+player+"
");
out.print("");
if (winner!=0) {
if (winner==player)
out.print("You win :-)");
else
out.print("Opponent wins :-(");
} else if (free>0) {
if (me)
out.print("Your move!");
else
out.print("Waiting for opponent...");
} else {
out.print("It's a draw.");
}
out.print("
");
out.print("");
}
}