You can have your exception extend RunetimeException, then you do not need to catch it

You could use the class ArithmeticException instead of creating your own class

public double divide(int value1, int value2) {
    if (value2 == 0)
        throw new ArithmeticException("Dividing by zero");
}

There are different ways. GregBrannon has written a tutorial where he shows a good way of handling it

Greg uses action commands, and I really find them useful too. You could also have an ActionListener for each of the events, but I think it just tend to mess up the code
Use interfaces so you easily can swap out your view, controller, or model

public interface IMenuBarView {
	public final String NEW_CLICKED;
	public final String ABOUT_ME_CLICKED;
	public final String EXIT_CLICKED;
	
	public void addNewClickedListener(ActionListener listener);
	public void addAboutMeClickedListener(ActionListener listener);
	public void addExitClickedListener(ActionListener listener);
}

public class MenuBarController implements ActionListener {
	
	public MenuBarController(IMenuBarView view) {
		view.addNewClickedListener(this);
		view.addAboutMeClickedListener(this);
		view.addExitClickedListener(this);
	}
	
	@Override
	public void actionPerformed(ActionEvent e) {
		switch (e.getActionCommand()) {
			case: IMenuBarView.NEW_CLICKED
				break;
			case: IMenuBarView.ABOUT_ME_CLICKED
				break;
			case: IMenuBarView.EXIT_CLICKED
				break;
		}
	}
}

There is no reason to pass your Main class to the MenuBar
Instead you should let MenuBar extend JMenuBar (Don't name your class MenuBar since there already exist such a class in the API)

Keep your instance variables private to encapsulate them and keep control in the MenuBar class
You really shouldn't allow anyone to modify the instance variables other than the MenuBar class

menuBar = new MenuBar();
setJMenuBar(menuBar);

public class MenuBar extends JMenuBar {
    private JMenu newMenu
    //...
}

Wow you really need to settle down and focus on one project/problem at a time
You have started so many topics the past days, all about different topics and projects

Seems like you want to solve all the world's problems at once... or at least make us solve them for you
You should be spending more time trying to solve the problems yourself

Just to follow up on g00se's post, I don't think everyone understand the file.length() / 8

int size = (int) (file.length() / 8);

It makes more sense when you read the documentation

Quote