Concurrency - SCJP Sun Certified Programmer for Java Platform SE6 - page 347

9.
10. public void setKeepGoing(boolean b) {
11. keepGoing = b;
12. }
13.
14. public void run() {
15. while(keepGoing) {
16. System.out.print(message + “ “);
17. try {
18. Thread.sleep(1000);
19. }catch(InterruptedException e) {}
20. }
21. System.out.println(“gone!”);
22. }
23. }
In the run method of MyThread , the message fi eld is printed in a while loop. The call
to Thread.sleep on line 18 causes the currently running thread (which is the MyThread
instance) to sleep for at least 1,000 milliseconds (one second). Therefore, this run method
prints a String over and over again with at least a one-second delay between printings.
The following Main program instantiates and starts a MyThread object. Because this
example extended Thread , there is no need to instantiate two objects. (When implementing
Runnable , you instantiate both the Runnable target and a Thread object.) The MyThread
object represents both the thread object and the runnable target. Study the Main program
and see if you can determine its result:
1. public class Main {
2. public static void main(String [] args) {
3. MyThread myThread = new MyThread(“going”);
4. myThread.start();
5. try {
6. Thread.sleep(6000);
7. }catch(InterruptedException e) {}
8.
9. myThread.setKeepGoing(false);
10. System.out.println(“End of main”);
11. }
12. }