Hi everyone,
i hope this can be considered the right place even though my situation involves the use of different programs and different programming languages.
However the main problem is with java connecting to mysql database i guess.

Basically I am using tomcat and mysql on ubuntu where i do deploy java files and use them as servlet,everthing works i can make web page that access the database and show me the results or search through them but I wanted to insert some data into the table and when i use it ,it say data has been added successfully but when i check no modification has been made.
this is my code to make it much clear

import java.io.*;
import javax.servlet.*;
import javax.servlet.http.*;
import java.text.SimpleDateFormat;
//import java.text.ParseException;
//import java.util.*;
import java.sql.*;

public class InsertStudentDetails extends HttpServlet {
public void doPost
(HttpServletRequest request,HttpServletResponse response)
throws ServletException, IOException {

PrintWriter out = response.getWriter();
String stName=request.getParameter("stName");
String stSurName= request.getParameter("stSurName");
String dCode=request.getParameter("dCode");
String dob=request.getParameter("dob");

//Here there will be dob validation which will check if the date format is correct

out.println("The date of birth format is incorrect");
SimpleDateFormat dateFormat = new SimpleDateFormat("yyyy/MM/dd");
if (dob.trim().length() != dateFormat.toPattern().length())

out.println("The date of birth format is incorrect");

//This side does create a connection with the database and inserts the valie captured from the html form

//setting variables for the sql connection
Connection conn =null; // Create connection object
String database = "NAME"; // Name of database
String user = "NAME"; //
String password = "PASSWORD";
String url = "jdbc:mysql://mudfoot.doc.stu.mmu.ac.uk/" + database;

} catch(Exception e) {

// connecting to database
conn = DriverManager.getConnection(url, user, password);

catch(SQLException se) {
// Create select statement and execute it

//this string does extract the greatest studentno which then will be used to make another studentno
String lastStNumber="SELECT studentno from students order by studentno desc LIMIT 1";
int stNumber=0;//=ConvertTo.int32(lastStNumber);
//string to insert data into the database;
String insertDataSql="insert into students(stundentno,firstname,degreecode,dob) values(" + 14 +
",'" + stName + "'," + stSurName + "," + dCode + ",'" + dob + ";";

System.err.println("DEBUG: Query: " + lastStNumber);
Statement stmt;
try {
stmt = conn.createStatement();
//ResultSet rs1 = stmt.executeQuery(lastStNumber);
//this one use the same ResultSet rs1 but executes the sql query which will insert data into the table

} catch (SQLException e) {
// TODO Auto-generated catch block

//stNumber=stmt.executeQuery(lastNumber);//executes a querty in sql to find the greatest studentno
//stNumber=rs1.getInt("studentno");//assigns the greatest number to stNumber
//executes the query to insert data in the table

out.println("<HTML><BODY><H3>The Data has been added Successfully</H3></BODY></HTML>");




I can't understand why it does not insert the data i put in the form which then calls this servlet which then process the data to update the database.

Thank you in advance