Tic-Tac-Toe

pom.xml

@@ -18,15 +18,20 @@
 
     <dependencies>
         <dependency>
-            <groupId>javax.servlet</groupId>
-            <artifactId>javax.servlet-api</artifactId>
-            <version>4.0.1</version>
+            <groupId>jakarta.servlet</groupId>
+            <artifactId>jakarta.servlet-api</artifactId>
+            <version>6.0.0</version>
             <scope>provided</scope>
         </dependency>
         <dependency>
-            <groupId>javax.servlet</groupId>
-            <artifactId>jstl</artifactId>
-            <version>1.2</version>
+            <groupId>jakarta.servlet.jsp.jstl</groupId>
+            <artifactId>jakarta.servlet.jsp.jstl-api</artifactId>
+            <version>3.0.0</version>
+        </dependency>
+        <dependency>
+            <groupId>org.glassfish.web</groupId>
+            <artifactId>jakarta.servlet.jsp.jstl</artifactId>
+            <version>3.0.1</version>
         </dependency>
     </dependencies>
 

src/main/java/com/tictactoe/Field.java

@@ -52,9 +52,11 @@ public Sign checkWin() {
         );
 
         for (List<Integer> winPossibility : winPossibilities) {
-            if (field.get(winPossibility.get(0)) == field.get(winPossibility.get(1))
-                && field.get(winPossibility.get(0)) == field.get(winPossibility.get(2))) {
-                return field.get(winPossibility.get(0));
+            Sign sign0 = field.get(winPossibility.get(0));
+            if ((sign0 != Sign.EMPTY)
+                    && (sign0 == field.get(winPossibility.get(1)))
+                    && (sign0 == field.get(winPossibility.get(2)))) {
+                return sign0;
             }
         }
         return Sign.EMPTY;

src/main/java/com/tictactoe/IndexServlet.java

@@ -0,0 +1,19 @@
+package com.tictactoe;
+
+import jakarta.servlet.ServletException;
+import jakarta.servlet.annotation.WebServlet;
+import jakarta.servlet.http.HttpServlet;
+import jakarta.servlet.http.HttpServletRequest;
+import jakarta.servlet.http.HttpServletResponse;
+
+import java.io.IOException;
+
+@WebServlet("")
+public class IndexServlet extends HttpServlet {
+
+    @Override
+    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
+        req.getRequestDispatcher("/start")
+                .forward(req, resp);
+    }
+}

src/main/java/com/tictactoe/LogicServlet.java

@@ -0,0 +1,90 @@
+package com.tictactoe;
+
+import jakarta.servlet.ServletException;
+import jakarta.servlet.annotation.WebServlet;
+import jakarta.servlet.http.HttpServlet;
+import jakarta.servlet.http.HttpServletRequest;
+import jakarta.servlet.http.HttpServletResponse;
+import jakarta.servlet.http.HttpSession;
+
+import java.io.IOException;
+import java.util.List;
+
+@WebServlet(name = "LogicServlet", value = "/logic")
+public class LogicServlet extends HttpServlet {
+
+    private static final String PATH_INDEX = "WEB-INF/index.jsp";
+
+    @Override
+    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
+        HttpSession currentSession = req.getSession();
+        Field field = extractField(currentSession);
+
+        if (checkWin(req, resp, currentSession, field)) {
+            return;
+        }
+
+        int index = getSelectedIndex(req);
+        Sign currentSign = field.getField().get(index);
+        if (Sign.EMPTY != currentSign) {
+            req.getRequestDispatcher(PATH_INDEX)
+                    .forward(req, resp);
+            return;
+        }
+        field.getField().put(index, Sign.CROSS);
+        if (checkWin(req, resp, currentSession, field)) {
+            return;
+        }
+
+        int emptyFieldIndex = field.getEmptyFieldIndex();
+        if (emptyFieldIndex >= 0) {
+            field.getField().put(emptyFieldIndex, Sign.NOUGHT);
+            if (checkWin(req, resp, currentSession, field)) {
+                return;
+            }
+        } else {
+            currentSession.setAttribute("draw", true);
+            List<Sign> data = field.getFieldData();
+            currentSession.setAttribute("data", data);
+            req.getRequestDispatcher(PATH_INDEX)
+                    .forward(req, resp);
+            return;
+        }
+
+        List<Sign> data = field.getFieldData();
+        currentSession.setAttribute("data", data);
+        req.getRequestDispatcher(PATH_INDEX)
+                .forward(req, resp);
+    }
+
+    private int getSelectedIndex(HttpServletRequest request) {
+        String click = request.getParameter("click");
+        boolean isNumeric = click.chars().allMatch(Character::isDigit);
+        return isNumeric ? Integer.parseInt(click) : 0;
+    }
+
+    private Field extractField(HttpSession currentSession) {
+        Object fieldAttribute = currentSession.getAttribute("field");
+        if (Field.class != fieldAttribute.getClass()) {
+            currentSession.invalidate();
+            throw new RuntimeException("Session is broken, try one more time");
+        }
+        return (Field) fieldAttribute;
+    }
+
+    private boolean checkWin(HttpServletRequest req,
+                             HttpServletResponse resp,
+                             HttpSession currentSession,
+                             Field field) throws IOException, ServletException {
+        Sign winner = field.checkWin();
+        if (winner != Sign.EMPTY) {
+            currentSession.setAttribute("winner", winner);
+            List<Sign> data = field.getFieldData();
+            currentSession.setAttribute("data", data);
+            req.getRequestDispatcher(PATH_INDEX)
+                    .forward(req, resp);
+            return true;
+        }
+        return false;
+    }
+}

src/main/java/com/tictactoe/RestartServlet.java

@@ -0,0 +1,20 @@
+package com.tictactoe;
+
+import jakarta.servlet.ServletException;
+import jakarta.servlet.annotation.WebServlet;
+import jakarta.servlet.http.HttpServlet;
+import jakarta.servlet.http.HttpServletRequest;
+import jakarta.servlet.http.HttpServletResponse;
+
+import java.io.IOException;
+
+@WebServlet(name = "RestartServlet", value = "/restart")
+public class RestartServlet extends HttpServlet {
+
+    @Override
+    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
+        req.getSession().invalidate();
+        req.getRequestDispatcher("/start")
+                .forward(req, resp);
+    }
+}

src/main/java/com/tictactoe/StartServlet.java

@@ -0,0 +1,26 @@
+package com.tictactoe;
+
+import jakarta.servlet.ServletException;
+import jakarta.servlet.annotation.WebServlet;
+import jakarta.servlet.http.HttpServlet;
+import jakarta.servlet.http.HttpServletRequest;
+import jakarta.servlet.http.HttpServletResponse;
+import jakarta.servlet.http.HttpSession;
+
+import java.io.IOException;
+import java.util.List;
+
+@WebServlet(name = "InitServlet", value = "/start")
+public class StartServlet extends HttpServlet {
+
+    @Override
+    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
+        HttpSession currentSession = req.getSession(true);
+        Field field = new Field();
+        List<Sign> data = field.getFieldData();
+        currentSession.setAttribute("field", field);
+        currentSession.setAttribute("data", data);
+        req.getRequestDispatcher("WEB-INF/index.jsp")
+                .forward(req, resp);
+    }
+}

src/main/webapp/WEB-INF/index.jsp

@@ -0,0 +1,80 @@
+<%@ page import="com.tictactoe.Sign" %>
+<%@ page contentType="text/html;charset=UTF-8"%>
+<!DOCTYPE html>
+<html>
+<head>
+    <title>Tic-Tac-Toe</title>
+    <link href="../static/main.css" rel="stylesheet">
+    <%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>
+    <script src="<c:url value="/static/jquery-3.6.0.min.js"/>"></script>
+</head>
+<body>
+<div class="game-container">
+    <h1>Tic-Tac-Toe</h1>
+    <div class="board">
+        <c:forEach var="sign" items="${data}" varStatus="status">
+            <c:choose>
+                <c:when test="${sign == Sign.CROSS}">
+                    <div class="cell x">X</div>
+                </c:when>
+                <c:when test="${sign == Sign.NOUGHT}">
+                    <div class="cell o">O</div>
+                </c:when>
+                <c:otherwise>
+                    <div class="cell" onclick="window.location='/logic?click=${status.index}'"></div>
+                </c:otherwise>
+            </c:choose>
+        </c:forEach>
+    </div>
+    <c:choose>
+        <c:when test="${draw}">
+            <div class="controls" id="endGameUI">
+                <div id="status">
+                    IT'S A DRAW
+                </div>
+                <button class="restart-btn" onclick="restart()">Start again</button>
+            </div>
+        </c:when>
+        <c:when test="${winner == Sign.CROSS}">
+            <div class="controls" id="endGameUI">
+                <div id="status">
+                    CROSSES WIN!
+                </div>
+                <button class="restart-btn" onclick="restart()">Start again</button>
+            </div>
+        </c:when>
+        <c:when test="${winner == Sign.NOUGHT}">
+            <div class="controls" id="endGameUI">
+                <div id="status">
+                    NOUGHTS WIN!
+                </div>
+                <button class="restart-btn" onclick="restart()">Start again</button>
+            </div>
+        </c:when>
+        <c:otherwise>
+            <div class="controls">
+                <div id="status">
+                    MESSAGE
+                </div>
+                <button class="restart-btn">Button</button>
+            </div>
+        </c:otherwise>
+    </c:choose>
+</div>
+<script>
+    function restart() {
+        $.get('/restart', function (data, status) {
+            if (status === 'success') {
+                window.location.href = '/';
+            } else {
+                alert('An error occurred: ${status}');
+            }
+        });
+    }
+
+    <c:if test="${(winner != null) || draw}">
+    document.getElementById('endGameUI').classList.add('show');
+    </c:if>
+</script>
+</body>
+</html>