寫一個打印時間的多線程，睡眠時間停頓爲1秒

import java.text.SimpleDateFormat;
import java.util.Date;

public class Clock {

	public static void main(String[] args) {
		Date date = new Date();
			
		SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
		while(true) {	
			try {
				Thread.sleep(1000);
				System.out.println(sdf.format(new Date()));
			} catch (InterruptedException e) {
				// TODO Auto-generated catch block
				e.printStackTrace();
			}
			
		}

	}

}