Java Countdown ends without returning into the main
===

I've a program that control an electronic component, my problem is the part of the countdown, practically when I call from the main the class CountDown when it ends it don't returns to the main. The program must always be active and read the first value in the main for call and start the countdown.
This is the code:

    public class CountDown {
    
    public static int a;
	
    public static Timer timer;

    public CountDown() {

    timer = new Timer();

    timer.schedule(new DisplayCountdown(), 0, 1000);

    }

    class DisplayCountdown extends TimerTask {

    int seconds = 15;

    public void run() {

    if (seconds > 0) {

    System.out.println(seconds + " seconds remaining");

    if(READING BY ELECTRONIC COMPONENT == 1){
	
	seconds=15;
	
    }
    else {
	seconds--;
    }

    } else {

    System.out.println("Countdown finished");

    CountDown.a=0;

    }

    }

    }

    public static void main(String args[]) {

	CountDown.a = 0;
    
    while(true){
    	
    	if(READING ELECTRONIC COMPONENT == 1){
    		    		
    		if (CountDown.a==0){
            		CountDown.a = 1;
        		new CountDown();
    			
    		}
    		
    	}
    	
    }
    	
    }
	
