How to add delay to while loop

Question

I have a while loop and what I want it to do is every 1 second count up an integer up to 10. The code that I have now simply spits out 1-10 as quick as it possibly can with no delay, I'm un-sure how to add a delay. package apackage;

public class loops {
    public static void main(String args[]){
        int countdown = 1;
        while (countdown < 10) {
            System.out.println(countdown);
            ++countdown;
        }
    }
}

So, thanks for reading and appreciate the help in advance.

Look at [`Thread#sleep`](http://docs.oracle.com/javase/7/docs/api/java/lang/Thread.html#sleep(long)) — August, Aug 06 '14 at 17:11

score 4 · Accepted Answer · answered Aug 06 '14 at 17:13

4

Change your code to this

public class loops {
    public static void main(String args[]) throws InterruptedException {
        int countdown = 1;
        while (countdown < 10){
            System.out.println(countdown);
            ++countdown;
            Thread.sleep(1000);
        }
    }
}

answered Aug 06 '14 at 17:13

odlund

247
1
5

5

Soon enough someone here will tell you that it's not accurate enough due to the additional time spent on the countdown itself at every iteration. – barak manos Aug 06 '14 at 17:14

score 1 · Answer 2 · answered Aug 06 '14 at 17:14

1

You may consider Thread.sleep()

Here is the tutorial

answered Aug 06 '14 at 17:14

JerryDeveloper

139
1
9

score 1 · Answer 3 · answered Aug 06 '14 at 17:21

1

Add this at the beginning of the loop:

long time = System.currentTimeMillis();

And add this at the end of the loop:

long wait = time + 1000 - System.currentTimeMillis();
if (wait > 0)
    Thread.sleep(wait);

answered Aug 06 '14 at 17:21

barak manos

29,648
10
62
114

How to add delay to while loop

3 Answers3