String mk =jTextField1.getText();
        String mn = jTextField2.getText();
        String ab =(String) jComboBox1.getSelectedItem();
        String bc = (String) jComboBox2.getSelectedItem();


        try{
            Class.forName("org.apache.derby.jdbc.EmbeddedDriver").newInstance();
           Connection con = (Connection) DriverManager.getConnection("jdbc:derby://localhost:1527/production");{
             String host ="jdbc:derby://localhost:1527/production";

                  Statement stmt = con.createStatement();
                    String query = "update PRODUCT set FACTORY=?,PRODUCT_NAME =?,UNIT=?,OPENING_BALANCE=?";
                  try  (PreparedStatement update = con.prepareStatement(query)){
                        update.setString(1, ab);
                        update.setString(2, mk);
                        update.setString(3, bc);
                        update.setString(4, mn);

                             update.executeUpdate();

                                jTextField1.setText(null);
                                jTextField2.setText(null);
                                    MainPanel.removeAll();
                                    MainPanel.add(jPanelStart1);
                                    MainPanel.repaint();
                                    MainPanel.revalidate();
                    }
                               JOptionPane.showMessageDialog(this, "Record has been inserted");

            }
        }
        catch(Exception e){
            JOptionPane.showMessageDialog(this, "invalid entry");

       }