Database not getting updated

Question

package com.sandy.servlets;
import javax.servlet.*;
import java.sql.*;
import javax.servlet.http.*;
import java.io.*;
public class FirstServlet extends HttpServlet
     Connection con;
     PreparedStatement ps;
     public void init(ServletConfig config) throws ServletException
     String driver=config.getInitParameter("driver");
     String cs = config.getInitParameter("url");
     String user=config.getInitParameter("user");
     String password=config.getInitParameter("pwd");
     try
          Class.forName(driver);
          con=DriverManager.getConnection(cs,user,password);
          ps=con.prepareStatement("INSERT INTO USER2 VALUES(?,?)");
     catch (ClassNotFoundException e)
          e.printStackTrace();
catch(SQLException e)
e.printStackTrace();
}//init()
public void destroy()
try
     if(ps!=null)
          ps.close();
     if(con!=null)
          con.close();
catch (SQLException e)
     e.printStackTrace();
public void doPost(HttpServletRequest request,HttpServletResponse response) throws ServletException,IOException
String a = request.getParameter("FirstName");
String b = request.getParameter("LastName");
try
   if(a!=null)
        if(b!=null)
     ps.setString(1,a);
     ps.setString(2,b);
     ps.executeUpdate();
catch (SQLException e)
     e.printStackTrace();
response.sendRedirect("user.html");
I ran the above program in tomcat,i didn't get any error but unfortunately database is not getting updated which is the sole purpose of this application
Edited by: sandy on Feb 8, 2011 12:33 AM

Answer 1

do you have some kind of auto commit? I don't see you commit the transaction anywhere.
By the way: this is terrible design. Perhaps you can open a connection on servlet init (still not a good design, but you seem to be in the learning phase so lets not focus on that now), but you should create the PreparedStatement, use it, commit it and then close it inside your doPost() method.