public ArrayList<Cliente> selectAllCliente(){
       ArrayList<Cliente> clientes = new ArrayList<Cliente>(); 
       try {
            Statement comando=connection.createStatement();
            ResultSet registro = comando.executeQuery("select * from Cliente");
            boolean especial = false;
            while (registro.next()){
                if(registro.getString(5).equalsIgnoreCase("1")){
                    especial=true;
                }
                Cliente c = new Cliente(registro.getInt(1), registro.getString(2), registro.getString(3), registro.getString(4), especial);
                clientes.add(c);
            }
        } catch (SQLException ex) {
            Logger.getLogger(GestionarCliente.class.getName()).log(Level.SEVERE, null, ex);
        }
          return clientes;
   }