Java event handlers

Question

Hi, I am writing a small Java app (on Windows, hence the _on_vista appended to my name).

I got 3 buttons, all of which will react to a click event, but do different things.

Is the following code the accepted way or is there a cleaner way I do not know about? On one half, it works, on the other half, something doesn't seem right...

Thanks

cool_button_1.addActionListener(new ActionListener() {
    public void actionPerformed(ActionEvent e) {
        coolfunction1();
    }
});

cool_button_2.addActionListener(new ActionListener() {
    public void actionPerformed(ActionEvent e) {
        coolfunction2();
    }
});

// etc ...

The functions that get called will spawn off threads as needed, so on and so forth.

UPDATE - Both were good (pretty much the same) answers. I accepted the one with the lower rep to share the wealth. Thanks again guys.

Answer 1

Yes, this is the correct way to do this. It's a bit clumsy (to have to write five long lines of code just to be able to call a method) but that's Java :(

Answer 2

I'd say that code is fine, as Java code goes. It's a good example for Java's often-criticized verbosity - in this case due to the lack of closures.

Answer 3

That’s not too bad. I prefer to use Actions and create JButtons from them:

Action fooAction = new AbstractAction() { ... };
JButton fooButton = new JButton(fooAction);

Answer 4

Its one of the correct ways to do it.

You are using anonymous listeners but there is an alternatif

nicely explained on http://java.sun.com/docs/books/tutorial/uiswing/events/intro.html

where you write a class that implements ActionListener and have it handle the logic for you

Answer 5

I tend to do something like this:

public class ButtonPanel implements ActionListener {
    JButton button1, button2, button3;
    public ButtonPanel() {
        button1 = new JButton(this);
        button2 = new JButton(this);
        button3 = new JButton(this):
        ...
    }

    public void ActionPerformed(ActionEvent e) {
        if( e.getSource() == button1 ) action1();
        else if( e.getSouce() == button2  ) action2();
        else if( e.getSource() == button3 ) action3();
    }
}