/*
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 * and open the template in the editor.
 */

import java.io.IOException;
import java.io.PrintWriter;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.logging.Level;
import java.util.logging.Logger;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;

/**
 *
 * @author DELL
 */
public class RemoveStudent extends HttpServlet {

    /**
     * Processes requests for both HTTP <code>GET</code> and <code>POST</code>
     * methods.
     *
     * @param request servlet request
     * @param response servlet response
     * @throws ServletException if a servlet-specific error occurs
     * @throws IOException if an I/O error occurs
     */
    protected void processRequest(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException, SQLException {
        response.setContentType("text/html;charset=UTF-8");
        try (PrintWriter out = response.getWriter()) {
            /* TODO output your page here. You may use following sample code. */
            HttpSession session = request.getSession();
java.sql.Connection con
                    = DriverManager.getConnection("jdbc:mysql://localhost:3306/gp?zeroDateTimeBehavior=convertToNull","root","mohamednabil00000");
            String email=request.getParameter("email");
            String query0="select user_id from gp.user_login where email = '"+email+"'";
             ResultSet rs;
              java.sql.Statement st = con.createStatement();
             rs = st.executeQuery(query0);
             if(rs==null){
                 session.setAttribute("msg", "This Email does not exist!");

             }
             else{
             while(rs.next()){

            String id = rs.getString(1);
            String query1 = "delete from gp.student_user where student_id=" + id;
            String query2 = "delete from gp.user_login where user_id=" + id;

            System.out.println("hereee " + id);

            try {
                st.executeUpdate(query1);
                st.executeUpdate(query2);
                request.getRequestDispatcher("admin_view_students.jsp").forward(request, response);
            } catch (SQLException | ServletException | IOException e) {

            }
        }
      }

        }
    }

    // <editor-fold defaultstate="collapsed" desc="HttpServlet methods. Click on the + sign on the left to edit the code.">
    /**
     * Handles the HTTP <code>GET</code> method.
     *
     * @param request servlet request
     * @param response servlet response
     * @throws ServletException if a servlet-specific error occurs
     * @throws IOException if an I/O error occurs
     */
    @Override
    protected void doGet(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        try {
            processRequest(request, response);
        } catch (SQLException ex) {
            Logger.getLogger(RemoveStudent.class.getName()).log(Level.SEVERE, null, ex);
        }
    }

    /**
     * Handles the HTTP <code>POST</code> method.
     *
     * @param request servlet request
     * @param response servlet response
     * @throws ServletException if a servlet-specific error occurs
     * @throws IOException if an I/O error occurs
     */
    @Override
    protected void doPost(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        try {
            processRequest(request, response);
        } catch (SQLException ex) {
            Logger.getLogger(RemoveStudent.class.getName()).log(Level.SEVERE, null, ex);
        }
    }

    /**
     * Returns a short description of the servlet.
     *
     * @return a String containing servlet description
     */
    @Override
    public String getServletInfo() {
        return "Short description";
    }// </editor-fold>

}