// Name: TimeJumpWithThreadJoin.java 
// 
import java.io.IOException; 
import java.util.concurrent.TimeUnit; 

public class TimeJumpWithThreadJoin { 
    public static void main(String[] args) throws InterruptedException { 
        SleepWorker thread = new SleepWorker("Worker0"); 
        thread.start(); 
        System.out.println("Waiting for thread join (should last for one minute)..."); 
        System.out.println("Meantime, set your system clock back (for ten minutes, for example) and measure time (on real clock) till Thread.join ended."); 
        thread.join(60 * 1000); 
        System.out.println("Thread.join ended()."); 
        if (thread.isAlive()) { 
            thread.interrupt(); 
        } 
        System.out.println("Done."); 
    } 
} 

class SleepWorker extends Thread { 
    static final public int SLEEP_TIME = 60 * 60 * 1000; // 1 hour 
    public SleepWorker(String name) { 
        super(name); 
    } 

    public void run() { 
        System.out.println("Thread goes to sleep."); 
        try { 
            Thread.sleep(SLEEP_TIME); 
        } catch (InterruptedException ie) { 
            System.out.println("Thread sleep interrupted."); 
        } 
        System.out.println("SleepWorker: '" + getName() + "' is done."); 
    } 
}