My name
is
Jon Skeet

Making method shorter when adding properties

I have two arrays with button-objects:

this.rightButtons = new JButton[MAX_RBUTTONS];
this.wrongButtons = new JButton[MAX_WBUTTONS];

And I add properties (color, etc.) to each one of these by:

private void preferences(String buttonType, int num) {
    if (buttonType.equalsIgnoreCase("right")) {
        this.rightButtons[num] = new JButton("");
        this.rightButtons[num].setToolTipText("gg");
        this.rightButtons[num].setPreferredSize(new Dimension(40, 40));
        this.rightButtons[num].setBackground(Color.LIGHT_GRAY);
        this.rightButtons[num].setOpaque(true);
        this.add(this.rightButtons[num]);                   
    } else if (buttonType.equalsIgnoreCase("wrong")) {
        this.wrongButtons[num] = new JButton("");
        this.wrongButtons[num].setToolTipText("gg");
        this.wrongButtons[num].setPreferredSize(new Dimension(40, 40));
        this.wrongButtons[num].setBackground(Color.LIGHT_GRAY);
        this.wrongButtons[num].setOpaque(true);
        this.add(this.wrongButtons[num]);
    }

As you see, they have the same properties. Is there a way to change this code to a shorter one? The only thing that changes is this.wrongButtons and this.rightButtons (name of array).

Yes, it's very simple - everything about the button is the same apart from where you're storing it. So create it, then store it:

private void preferences(String buttonType, int num) {
    JButton button = new JButton("");
    button.setToolTipText("gg");
    button.setPreferredSize(new Dimension(40, 40));
    button.setBackground(Color.LIGHT_GRAY)
    button.setOpaque(true);
    add(button);
    JButton[] array = buttonType.equalsIgnoreCase("right")
        ? rightButtons : wrongButtons;
    array[num] = button;
}

(This assumes every button type is either "right" or "wrong".)

Personally I'd advise using lists instead of arrays, by the way...

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