Can you please recomend a better solution than this?

Question

I use a servlet to send data from a form to a Mysql database.
The servlet code is the following.
When i submit the form i receive an Error 500 from Tomcat upon the 69th line of the code.
The code has as follows.
package mypackage;
import java.sql.*;
import java.io.*;
import javax.servlet.*;
import javax.servlet.http.*;
public class GroupRegistration extends HttpServlet
Connection con;
public void doPost (HttpServletRequest req, HttpServletResponse res)
throws ServletException, java.io.IOException
handleForm(req, res);
public void init() throws ServletException {
try{
/* Loading the driver for the database */
Class.forName("com.mysql.jdbc.Driver");
Connection con = DriverManager.getConnection("jdbc:mysql://localhost/se?user=luser&password=Ztgtkpz2");
catch (ClassNotFoundException e) {
throw new UnavailableException("Couldn't load JdbcOdbcDriver");
catch (SQLException e) {
throw new UnavailableException("Couldn't get db connection");
private void handleForm(HttpServletRequest req, HttpServletResponse res)
throws ServletException {
//ServletOutputStream out = res.OutputStream();
//res.setContentType("text/html");
//Extract the form Data Here
String group = req.getParameter("GroupNo");
String Name1 = req.getParameter("Name1");
String LoginID1 = req.getParameter("LoginID1");
String Name2 = req.getParameter("Name2");
String LoginID2 = req.getParameter("LoginID2");
String Name3 = req.getParameter("Name3");
String LoginID3 = req.getParameter("LoginID3");
String Name4 = req.getParameter("Name4");
String LoginID4 = req.getParameter("LoginID4");
String URL = req.getParameter("URL");
String Title2 = req.getParameter("Title2");
String date = req.getParameter("date");
String INSERT = "INSERT INTO registration (groupno, name1, loginid1, name2, loginid2, name3, loginid3, name4, loginid4, url, topic, date) VALUES (" + group + "," + Name1 + "," + LoginID2 + "," + Name2 + "," + LoginID2 + "," + Name3 + "," + LoginID3 + "," + Name4 + "," + LoginID4 + "," + URL + "," + Title2 + "," + date + ")";
PreparedStatement pstmt = null;
try{
LINE69 pstmt = con.prepareStatement(INSERT);
pstmt.executeUpdate();
catch (SQLException e) {
throw new ServletException(e);
finally {
try {
if (pstmt != null)pstmt.close();
catch (SQLException ignored){
Can you please recomend a solution to my problem.
If i mange to overcome the bug do you have any suggestions upon connection pooling or anythink that will make it to run smoothly?
Thank you for your time.

Answer 1

Look where you try to populate the connection variable con:
try{
/* Loading the driver for the database */
Class.forName("com.mysql.jdbc.Driver");
Connection con = DriverManager.getConnection("jdbc:mysql://localhost/se?user=luser&password=Ztgtkpz2");
Notice that you redeclared Connection con as a local variable.
try this instead:
try{
/* Loading the driver for the database */
Class.forName("com.mysql.jdbc.Driver");
con = DriverManager.getConnection("jdbc:mysql://localhost/se?user=luser&password=Ztgtkpz2");