How can I run a code for multiple JButtons?

Question

I want run a code for JButtons I want.

I search for this in Internet but I can't find a solution for swing applications.

b1.setFont(new Font("Arial", Font.PLAIN, (h / 25)));
b2.setFont(new Font("Arial", Font.PLAIN, (h / 25)));
b3.setFont(new Font("Arial", Font.PLAIN, (h / 25)));
b4.setFont(new Font("Arial", Font.PLAIN, (h / 25)));
b5.setFont(new Font("Arial", Font.PLAIN, (h / 25)));
b6.setFont(new Font("Arial", Font.PLAIN, (h / 25)));
b7.setFont(new Font("Arial", Font.PLAIN, (h / 25)));
b8.setFont(new Font("Arial", Font.PLAIN, (h / 25)));
b9.setFont(new Font("Arial", Font.PLAIN, (h / 25)));

I tried below code but I could not use JButton properties

JButton[] buttons = new JButton[];

I declare it

buttons[0] = b1;
buttons[1] = b2;
buttons[2] = b3;
buttons[3] = b4;
buttons[4] = b5;
buttons[5] = b6;
buttons[6] = b7;
buttons[7] = b8;
buttons[8] = b9;

But this didn't work:

buttons.setFont(new Font("Arial", Font.PLAIN, (h / 25)));

Answer 1

Step 1: You create an array, and fill it with the buttons.

JButton[] buttons = {b1,b2,b3,b4,b5,b6,b7,b8,b9};

Note: this already fills the array with the buttons, so statements like this:

buttons[0] = b1;
buttons[1] = b2;
buttons[2] = b3;

are redundant.

Step 2: Iterate over the array

for ( JButton button : buttons ) {
  // here you are to call the setFont
}

Step 3: Set the font

for ( JButton button : buttons ) {
  button.setFont(new Font("Arial", Font.PLAIN, (h / 25)));
}

Answer 2

If you do not want to keep the button as fields or in a structure AND the buttons are in one container (if they are in a different container, you will have to do more), another approach would be to use Darryl Burke's SwingUtils class .

So let's see how easier it would be:

for (JButton b : SwingUtils.getDescendantsOfClass(JButton.class, panelWithButtons)) {
    b.setFont(new Font("Tahoma",Font.BOLD,14));
}

Voilà! All buttons in "panelWithButtons" JPanel has this font. No fields kept, no array kept.