Program 2
package controller;
import dao.StudentDAO;
import java.io.IOException;
import java.io.PrintWriter;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
public class DeleteByRno extends HttpServlet {
protected void processRequest(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
response.setContentType("text/html;charset=UTF-8");
PrintWriter out = response.getWriter();
try
{
/* TODO output your page here. You may use following sample code. */
out.println("<!DOCTYPE html>");
out.println("<html>");
out.println("<head>");
out.println("<title>Servlet DeleteByRno</title>");
out.println("</head>");
out.println("<body>");
out.println("<center>");
int rno;
rno=Integer.parseInt(request.getParameter("txtRno"));
StudentDAO sd=new StudentDAO();
if(sd.deleteByRno(rno))
out.println("<font color=green size=5>.............Record Deleted...........");
else
out.println("<font color=red size=5>.............Record Not Found...........");
out.println("</center>");
out.println("</body>");
out.println("</html>");
}
catch(Exception e)
{
out.println(e);
}
}
@Override
protected void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
// processRequest(request, response);
}
@Override
protected void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException
{
processRequest(request, response);
}
@Override
public String getServletInfo() {
return "Short description";
}// </editor-fold>
}
Program 3
package controller;
import dao.StudentDAO;
import java.io.IOException;
import java.io.PrintWriter;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
import model.Student;
public class DeleteByRno1 extends HttpServlet {
protected void processRequest(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
response.setContentType("text/html;charset=UTF-8");
PrintWriter out = response.getWriter();
try
{
/* TODO output your page here. You may use following sample code. */
out.println("<!DOCTYPE html>");
out.println("<html>");
out.println("<head>");
out.println("<title>Servlet DeleteByRno1</title>");
out.println("</head>");
out.println("<body>");
out.println("<center>");
int rno;
rno=Integer.parseInt(request.getParameter("txtRno"));
StudentDAO sd=new StudentDAO();
Student S;
S=sd.searchByRno(rno);
if(S==null)
out.println("<font color=red size=5>............Record not found.........</font>");
else
{
HttpSession session=request.getSession(true);
session.setAttribute("rollno", rno);
out.println("<font color=blue size=5>Are You Sure Want To Delete</font>");
out.println("<table border=1>");
out.println("<tr>");
out.println("<th>Roll No</th>");
out.println("<th>Name</th>");
out.println("<th>Phyics</th>");
out.println("<th>Cmehistry</th>");
out.println("<th>Maths</th>");
out.println("</tr>");
out.println("<td>"+S.getRno()+"</td>");
out.println("<td>"+S.getName()+"</td>");
out.println("<td>"+S.getPhy()+"</td>");
out.println("<td>"+S.getChem()+"</td>");
out.println("<td>"+S.getMath()+"</td>");
out.println("<form method=post action=DeleteData>");
out.println("<td><input type=submit value=Delete></td>");
out.println("</form>");
out.println("</table>");
}
out.println("</center>");
out.println("</body>");
out.println("</html>");
}
catch(Exception e)
{
}
}
@Override
protected void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
// processRequest(request, response);
}
@Override
protected void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
processRequest(request, response);
}
@Override
public String getServletInfo() {
return "Short description";
}// </editor-fold>
}
Program 4
/*
* To change this license header, choose License Headers in Project Properties.
* To change this template file, choose Tools | Templates
* and open the template in the editor.
*/
package controller;
import dao.StudentDAO;
import java.io.IOException;
import java.io.PrintWriter;
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 admin
*/
public class DeleteData 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 {
response.setContentType("text/html;charset=UTF-8");
try (PrintWriter out = response.getWriter()) {
/* TODO output your page here. You may use following sample code. */
out.println("<!DOCTYPE html>");
out.println("<html>");
out.println("<head>");
out.println("<title>Servlet DeleteData</title>");
out.println("</head>");
out.println("<body>");
out.println("<h1>Servlet DeleteData at " + request.getContextPath() + "</h1>");
out.println("</body>");
out.println("</html>");
}
}
// <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 {
processRequest(request, response);
}
/**
* 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
{
HttpSession session=request.getSession();
PrintWriter out=response.getWriter();
int rno;
rno=Integer.parseInt(session.getAttribute("rollno").toString());
StudentDAO sd=new StudentDAO();
if(sd.deleteByRno(rno))
out.println("<font color=red size=10>Record Deleted............</font>");
}
/**
* Returns a short description of the servlet.
*
* @return a String containing servlet description
*/
@Override
public String getServletInfo() {
return "Short description";
}// </editor-fold>
}
