error oracle database connection?

hi now i am trying to connect oracle database and also insert my data into table, but it's not working.. I created one user registration form. when i give values in the form, i want stored data in oracle table. my table name is logininfoclient_sla. this is my coding:

newuser_db.java

package com.sla;

import java.io.IOException;
import java.io.PrintWriter;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.PreparedStatement;


import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.http.HttpServlet;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;


/**
 * Servlet implementation class newuser_db
 */
public class newuser_db extends HttpServlet {
    private static final long serialVersionUID = 1L;
    PreparedStatement stmt=null;
    Connection con =null;
    ResultSet rs=null;


    /**
     * @see HttpServlet#HttpServlet()
     */
    public newuser_db() {
        super();
        // TODO Auto-generated constructor stub
    }
    @Override
    public void init() throws ServletException {
        // TODO Auto-generated method stub
        super.init();
        try
        {
            Class.forName("sun.Jdbc.Odbc.JdbcOdbcDriver");
        }
        catch (ClassNotFoundException ex)
        {
            ex.printStackTrace();
        }


        try
        {
            con =DriverManager.getConnection("Jdbc:odbc:servletdb","system","balaji");

        }
        catch(SQLException ex)
        {
            ex.printStackTrace();
        }



        // TODO Auto-generated method stub
    }

    @Override
    public void service(ServletRequest arg0, ServletResponse arg1)
            throws ServletException, IOException {
        // TODO Auto-generated method stub
        super.service(arg0, arg1);
        PrintWriter out=arg1.getWriter();
        String s1=arg0.getParameter("USERID");
        String s2=arg0.getParameter("FIRSTNAME");
        String s3=arg0.getParameter("LASTNAME");
        String s4=arg0.getParameter("EMAILID");
        String s5=arg0.getParameter("ORGNAME");
        String s6=arg0.getParameter("MOBILENO");
        String s7=arg0.getParameter("PHONENO");
        String s8=arg0.getParameter("PASSWORD");

        out.println("inserted");
        out.println(s1);




        out.println("inserted1");
        //String sql="insert into userdetails values(ka.nextval,"+s1+","+s2+","+s3+","+s4+","+s5+","+s6+","+s7+",56,'de',01-jan-98)";
        PreparedStatement stmt1;
        try {
            stmt1 = con.prepareStatement("insert into login_info_client_sla values(?,?,?,?,?,?,?,?)");
            stmt1.setString(1,s1);
            stmt1.setString(2,s2);
            stmt1.setString(3,s3);
            stmt1.setString(4,s4);
            stmt1.setString(5,s5);
            stmt1.setString(6,s6);
            stmt1.setString(7,s7);
            stmt1.setString(8,s8);


            //stmt1.executeUpdate();
            out.println("inserted2");
            stmt1.executeUpdate();
            out.println("inserted3");
        } catch (SQLException e1) {
            // TODO Auto-generated catch block
        out.println(e1);

        }


    }
    @Override
    public void destroy() {
        // TODO Auto-generated method stub
        super.destroy();
        try
        {
            if(stmt!=null)
                stmt.close();
            stmt=null;

        }
        catch (SQLException ex)
        {
            ex.printStackTrace();
        }
        try
        {
            if(con!=null)
                con.close();
            con=null;

        }
        catch (SQLException ex)
        {
            ex.printStackTrace();
        }
    }



    /**
     * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
     */
    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        // TODO Auto-generated method stub
    }

    /**
     * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
     */
    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        // TODO Auto-generated method stub
    }

}

desing jsp page; newuser_reg.jsp

<%@ page language="java" contentType="text/html; charset=ISO-8859-1"
    pageEncoding="ISO-8859-1"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
<title>Insert title here</title>
</head>
<body>
<form action="newuser_db" method="post">
<center><font size="15" color="agenda">SLA Customer Details</font></center>
<table><tr><td>E-Mail id* </td><td>:</td> <td> <input type="text" value="" name="EMAILID"></input></td></tr>
<tr><td>First Name* </td><td>:</td> <td> <input type="text" value="" name="FIRSTNAME"></input></td></tr>
<tr><td>Last Name* </td><td>:</td> <td> <input type="text" value="" name="LASTNAME"></input></td></tr>
<tr><td>Org Name* </td><td>:</td> <td> <input type="text" value="" name="ORGNAME"></input></td></tr>
<tr><td>Password* </td><td>:</td> <td> <input type="text" value="" name="PASSWORD"></input></td></tr>
<tr><td>Mobile No* </td><td>:</td> <td> <input type="text" value="" name="MOBILENO"></input></td></tr>
<tr><td>Phone* </td><td>:</td> <td> <input type="text" value="" name="PHONENO"></input></td></tr>
<tr><td></td><td><input type="submit" value="Add"/></td></tr>
</table>



</form>
</body>
</html>

please help me.....i am new for this application.....