// fileMenu.add(openMenuItem);
exitMenuItem.addActionListener(this);
fileMenu.add(exitMenuItem);
menuBar.add(fileMenu);
mainFrame.setJMenuBar(menuBar);
sudokuGridView = new SudokuGridView();
droolsSudokuGridModel = new DroolsSudokuGridModel(SudokuGridSamples.getInstance().getSample("Simple"));
mainFrame.setLayout(borderLayout);
mainFrame.add(BorderLayout.CENTER, sudokuGridView);
// buttonPanel.add(fireOneRuleButton);
buttonPanel.add(solveButton);