try {

                Connection con = DriverManager.getConnection("jdbc:mysql://localhost:3306/sistemarfid?useUnicode=yes&characterEncoding=UTF-8&useSSL=false&useTimezone=true&serverTimezone=UTC", "root", "12345");

                String sql = "update produto set descricao=?, cod_barras=?, local_armazem=?, nome_forn=?, cod_fornecedor where cod_produto=?";

                PreparedStatement stmtedit = con.prepareStatement(sql);


                stmtedit.setString(1, descricao_produto.getText());
                stmtedit.setString(2, codigo_barras.getText());
                stmtedit.setString(3, local_armazenagem.getText());
                stmtedit.setString(4, fornecedor.getText());
                stmtedit.setString(5, codigo_fornecedor.getText());
                stmtedit.setString(6, codigo_produto.getText());


                 stmtedit.executeUpdate(sql);
                //stmtedit.executeUpdate();
                //stmtedit.execute();

                stmtedit.close();
                con.close();

                JOptionPane.showMessageDialog(jButton1, this, "Produto alterado!", getDefaultCloseOperation());

            }catch (SQLException e){

                System.out.println (e);
                //e.printStackTrace();


            }

            catch (Exception e) {System.out.println (e);}