mallak alrooh 0 Newbie Poster

Hello every body>> ^_^
I want your help, I have done code that retrive data from the databse and the user can add data in the database , I want to do validition for student ID, if its in the datase before (if its valid before or not) I need to use AJAX to do that, I wrote the whole code for the servlet and jsp and it work good, now I need to add the code for AJAX but I don't know where to add it and what to write. when I search I see code but I don't know where is the good place for that code to be added , please I need your help quickly,
Please If you have code that can work good with my code please add it.

This is servlet code:

@WebServlet(name = "Quiz", urlPatterns = {"/Quiz"})
public class Quiz extends HttpServlet {

    protected void processRequest(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException, ClassNotFoundException, InstantiationException, SQLException {
        response.setContentType("text/html;charset=UTF-8");
        PrintWriter out = response.getWriter();



        try {
            String StudentID = request.getParameter("StudentID");
            String StudentName = (String) request.getParameter("Studentname");
            String CourseID = (String) request.getParameter("CourseID");
            String CourseName = (String) request.getParameter("Coursename");
            String Tmarks = (String) request.getParameter("totalMarks");


//Connect to Database
            Connection con = null;
            Statement stmt = null;
            String databaseURL = "jdbc:mysql://localhost:3306/user";
            String driverName = "com.mysql.jdbc.Driver";
            String user = "root";
            String password = "";
            try {
                Class.forName(driverName).newInstance();
                con = (Connection) DriverManager.getConnection(databaseURL, user, password);
                stmt = (Statement) con.createStatement();
            } catch (Exception e) {
                System.out.println("ERROR Connecting to DB: " + e);
                return;
            }
//Insert data
            String insertStmt = "insert into quiz values ("
                    + "'" + StudentID + "', "
                    + "'" + StudentName + "', "
                    + "'" + CourseID + "', "
                    + "'" + CourseName + "',"
                    + "'" + Tmarks + "'"
                    + ")";
            try {
                stmt.executeUpdate(insertStmt);
                RequestDispatcher dispatcher =
                        getServletContext().getRequestDispatcher("/Inserted.jsp");
                dispatcher.forward(request, response);
            } catch (Exception e) {
                stmt.executeUpdate(insertStmt);
                RequestDispatcher dispatcher =
                        getServletContext().getRequestDispatcher("/ErrorDB.jsp");
                dispatcher.forward(request, response);
                System.out.println("ERROR: Insert into DB: " + e);
                return;
            }
//Close database

            stmt.close();
            con.close();
            out.println("<html>");
            out.println("<head>");
            out.println("<title>Servlet Quiz</title>");
            out.println("</head>");
            out.println("<body>");
            // out.println("<h1>Servlet Quiz at " + request.getContextPath() + "</h1>");
            out.println("</body>");
            out.println("</html>");


        } finally {
            out.close();


        }
    }

This is JSP code:

<%@page contentType="text/html" pageEncoding="UTF-8"%>
<!DOCTYPE html>
<html>


    <head>
        <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
        <title>JSP Page</title>
    </head>
    <body bgcolor="=#cccccc">
    <center>
        <h1 align="center">Student Grade information</h1>


        <form name="form" action="Quiz" method="POST" >
            <table border="1" bordercolor="red" table bgcolor="orange">
                <thead>
                    <tr>
                        <th> Student ID </th>
                        <th><input type="text" name="StudentID" value="" /><p></th>
                    </tr>
                    </thead>
                <tbody>
                    <tr>
                        <td> Student Name </td>
                        <td><input type="text" name="Studentname" value="" /><p></td>
                    </tr>
                    <tr>
                        <td>Course ID </td>
                        <td><input type="text" name="CourseID" value="" /><p></td>
                    </tr>
                    <tr>
                        <td>Course Name </td>
                        <td><input type="text" name="Coursename" value="" /><p></td>
                    </tr>
                    <tr>
                        <td>Total Mark </td>
                        <td><input type="text" name="totalMarks" value="" /><p></td>
                    </tr>
                    <tr>
                        <td></td>

                    </tr>
                </tbody>
            </table>

            &nbsp&nbsp&nbsp&nbsp&nbsp&nbsp <input type="submit" value="Submit" name="submit" />

        </form>


        <a href="getData.jsp">Display table of student information</a> <p>
            <a href="home.jsp">home page</a>
            </body>
            </html>

Thanks in advance, I'm waitting your help