SQL JDBC Driver: Não consigo conectar

package br.Modulo1;

import java.io.IOException;
import java.io.PrintWriter;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.sql.*;

 public class Insert extends javax.servlet.http.HttpServlet implements javax.servlet.Servlet {
   static final long serialVersionUID = 1L;
   
	String url="jdbc:odbc:teste";
	Connection con;
	Statement smtp;
	ResultSet rs;	
	
	public Insert() {
		super();
	}   	
	
	protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		
	}  	
	

	protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		response.setContentType("text/html");
		PrintWriter out = response.getWriter();
		

        try{
			Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");
			con = DriverManager.getConnection(url,"","");
			smtp = con.createStatement();	    
	        
	        }catch(Exception s){s.printStackTrace();}   
	        
	        try{
				String SQL_INSERT = "insert into tabela(nome) values('" + "grava" +  "')";
				Statement instrucao = con.createStatement();
				instrucao.executeUpdate(SQL_INSERT);
				instrucao.close();
			}catch(SQLException ex){System.err.println("erro de sql: "  + ex.getMessage());
			}
			
	        try{
				con.close();
			}catch(SQLException e){}

		
	}   	  	    
}