I follow the same procedure what you send by the links.but i got the same errors

coding is:
import java.io.*; 
import java.sql.*;
import javax.servlet.*; 
import javax.servlet.http.*;

public class InsertServlet extends HttpServlet{
    public void doPost(HttpServletRequest req,HttpServletResponse res) throws ServletException,IOException {
        res.setContentType("text/html");
        int count=0; 
        PrintWriter out = res.getWriter(); 
        String FirstName=req.getParameter("FirstName");
        String LastName=req.getParameter("LastName");
        String Email=req.getParameter("Email");
        String Password=req.getParameter("Password"); 
        String ConformPassword=req.getParameter("ConformPassword");
        String Dateofbirth=req.getParameter("Dateofbirth"); 
        int Age=Integer.parseInt(req.getParameter("Age"));
        String Gender=req.getParameter("Gender");
        String Address=req.getParameter("Address"); 
        String Country=req.getParameter("Country");
        String State=req.getParameter("State"); 
        String City=req.getParameter("City"); 
        int Telephone=Integer.parseInt(req.getParameter("Telephone"));
        int Mobile=Integer.parseInt(req.getParameter("Mobile")); 
        String Howdidyouhear=req.getParameter("Howdidyouhear");

PreparedStatement pstm=null; 

  try{
         Class.forName("com.microsoft.sqlserver.jdbc.SQLServerDriver ");
         String connectionUrl = ("jdbc:sqlserver://localhost:1433;database=sree;integratedSecurity=true");
         Connection con = DriverManager.getConnection(connectionUrl);
                  pstm=con.prepareStatement("insert into stureg(?,?,?,?,?,?,?,?,?,?,?,?,?,?,?)"); 
                  pstm.setString(1,FirstName);
                  pstm.setString(2,LastName);
                  pstm.setString(3,Email);
                  pstm.setString(4,Password);
                  pstm.setString(5,ConformPassword);
                  pstm.setString(6,Dateofbirth);
                  pstm.setInt(7,Age);
                  pstm.setString(8,Gender);
                  pstm.setString(9,Address);
                  pstm.setString(10,Country);
                  pstm.setString(11,State);
                  pstm.setString(12,City);
                  pstm.setInt(13,Telephone);
                  pstm.setInt(14,Mobile);
                  pstm.setString(15,Howdidyouhear);
                  int i=pstm.executeUpdate();
                     if(i==1){
                       System.out.print("insert");
                     }                      
                     else{
                       System.out.print("not insert");
                      }
                   }
                   catch(Exception e){
                   e.getMessage();
                   }
                }
            }


Errors are:

C:\Program Files\Apache Software Foundation\Tomcat 6.0\webapps\website_app\WEB-I
NF\classes>javac InsertServlet.java
InsertServlet.java:3: package javax.servlet does not exist
import javax.servlet.*;
^
InsertServlet.java:4: package javax.servlet.http does not exist
import javax.servlet.http.*;
^
InsertServlet.java:6: cannot find symbol
symbol: class HttpServlet
public class InsertServlet extends HttpServlet{
                                   ^
InsertServlet.java:7: cannot find symbol
symbol  : class HttpServletRequest
location: class InsertServlet
    public void doPost(HttpServletRequest req,HttpServletResponse res) throws Se
rvletException,IOException {
                       ^
InsertServlet.java:7: cannot find symbol
symbol  : class HttpServletResponse
location: class InsertServlet
    public void doPost(HttpServletRequest req,HttpServletResponse res) throws Se
rvletException,IOException {
                                              ^
InsertServlet.java:7: cannot find symbol
symbol  : class ServletException
location: class InsertServlet
    public void doPost(HttpServletRequest req,HttpServletResponse res) throws Se
rvletException,IOException {
                                                                              ^
6 errors