public void actionPerformed(java.awt.event.ActionEvent evt) {
                    String s = (String)JOptionPane.showInputDialog(null,"Zadejte název matice","Database save",JOptionPane.PLAIN_MESSAGE,null,null,"");
                    if(s!=null){
                        Window w = SwingUtilities.getWindowAncestor(op);
                        if (w != null) {
                            w.dispose();
                        }
                        databaseSave(s,m3);
                    }
                }