If you want to pause then use java.util.concurrent.TimeUnit:
TimeUnit.SECONDS.sleep(1);
To sleep for one second or
TimeUnit.MINUTES.sleep(1);
To sleep for a minute.
As this is a loop, this presents an inherent problem - drift. Every time you run code and then sleep you will be drifting a little bit from running, say, every second. If this is an issue then don't use sleep.
Further, sleep isn't very flexible when it comes to control.
For running a task every second or at a one second delay I would strongly recommend a ScheduledExecutorService and either scheduleAtFixedRate or scheduleWithFixedDelay.
For example, to run the method myTask every second (Java 8):
public static void main(String[] args) {
final ScheduledExecutorService executorService = Executors.newSingleThreadScheduledExecutor();
executorService.scheduleAtFixedRate(App::myTask, 0, 1, TimeUnit.SECONDS);
}
private static void myTask() {
System.out.println("Running");
}
And in Java 7:
public static void main(String[] args) {
final ScheduledExecutorService executorService = Executors.newSingleThreadScheduledExecutor();
executorService.scheduleAtFixedRate(new Runnable() {
@Override
public void run() {
myTask();
}
}, 0, 1, TimeUnit.SECONDS);
}
private static void myTask() {
System.out.println("Running");
}