Visibility of buttons in java

hello is my first query in this portal I would like to know if there is any way to make visible buttons sequentially try with a for cycle but do not leave so I have my code maybe there is someone who has a solution

Random random = new Random();

for (int i = 0; i < 10; i++) {
    System.out.println(+i+"  ");

    boton+i.setVisible(true);

    try {
        Thread.sleep(random.nextInt(8000));
    } catch (InterruptedException e) {}
}