laczenie z bazą danych

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
public class DemoDB {
    public static void main(String[] args) {
        try{
            Class.forName("org.postgresql.Driver");
            Connection con = DriverManager.getConnection("jdbc:postgresql://localhost:5432/postgres","postgres","1234567890");
            PreparedStatement stmt = con.prepareStatement("select kolor from auta");
            ResultSet Rs = stmt.executeQuery();
            while (Rs.next()) {
                System.out.println(Rs.getInt(1)+" "+Rs.getString(2));
            }


        } catch(Exception ex){
            System.out.println(ex.getMessage());
        }
    }
}