public class ShutDownHookEx
{
    public ShutDownHookEx()
    {
        // add a shutdown hook. this will be called when the
        // JVM will terminate conditionally or unconditionally.
        Runtime.getRuntime().addShutdownHook(new Thread()
        {
            public void run()
            {
                System.out.println("from shutdown hook");
            }
        });
    }
 
    public void startLoop()
    {
        // a counter thread, waits for 5 seconds and prints value of n 
        Thread t = new Thread()
        {
            public void run()
            {
                int n = 0;
                while (n < 1000)
                {
                    try
                    {
                        sleep(5000);
                        System.out.println("n : " + n);
                    }
                    catch (InterruptedException e)
                    {
                        e.printStackTrace();
                    }
                    n++;
                }
            }
        };
        t.start();
    }
 
    public static void main(String[] args)
    {
        ShutDownHookEx sdhe = new ShutDownHookEx();
        sdhe.startLoop();
    }
}