// concurrent/QuittableTask.java
// (c)2017 MindView LLC: see Copyright.txt
// We make no guarantees that this code is fit for any purpose.
// Visit http://OnJava8.com for more book information.
import java.util.concurrent.atomic.AtomicBoolean;
import onjava.Nap;

public class QuittableTask implements Runnable {
 final int id;
 public QuittableTask(int id) { this.id = id; }
 private AtomicBoolean running =
 new AtomicBoolean(true);
 public void quit() { running.set(false); }
 @Override
 public void run() {
 while(running.get()) // [1]
 new Nap(0.1);
 System.out.print(id + " "); // [2]
 }
}