private JFrame getJFrame() {
		if (jFrame == null) {
			jFrame = new JFrame();
			jFrame.setSize(new Dimension(550, 220));
			jFrame.setResizable(false);
			jFrame.setTitle("Cryptanalyse");
			jFrame.setLocationRelativeTo(null);
			jFrame.setContentPane(getJContentPane());
			jFrame.getRootPane().setDefaultButton(getButOK());
			jFrame.setJMenuBar(this.menu);
			jFrame.addWindowListener(new java.awt.event.WindowAdapter() {
				public void windowClosing(java.awt.event.WindowEvent e) {
					System.exit(0);
				}
			});
		}
		return jFrame;
	}