Why isn't my timer working?

public class TimerProgram extends JFrame {
    public TimerProgram(){

       int  DELAY=1000;
       Timer t = new Timer(DELAY,new TimerListener());
          t.start();

    }
      class TimerListener implements ActionListener{
        public void actionPerformed(ActionEvent e) {
            System.out.println("Hello");

          }
        }     

      public static void main(String[]args){
          new TimerProgram();
      }
}

I am trying to make a timer that outputs every second the word hello, but it seems that when I type as the DELAY value 1000 , it outputs hello once and then it terminates. What am I doing wrong ? All help appreciated!