定时处理任务Timer)

Timer类，是一种工具，可安排任务执行一次或者定期重复重复执行

public class OneTime {
	public static void main(String[] args) {
		Timer timer = new Timer();
		TimerTask task = new MyTimerTask();
		Date date = new Date(System.currentTimeMillis() + 3000);
		//过三秒之后执行任务
		timer.schedule(task, date);
	}
}

public class MyTimerTask extends TimerTask{
	@Override
	public void run() {
		System.out.println("MyTimerTask");
	}
}

public class RepeatDo { 
	public static void main(String[] args) { 
	Timer timer=new Timer(); 
	//创建一个计时器过两秒后每隔3S 执行一次操作 
	timer.schedule(new MyTimerTask1(1,timer), 2000, 1L*3000); 
	} 
} 

public class MyTimerTask1 extends TimerTask{
	int round_id;
	Timer timer;
	public MyTimerTask1(int round,Timer timer) {
		this.round_id = round;
		this.timer = timer;
	}
	@Override
	public void run() {
		this.round_id++;
		System.out.println("repeat : " + this.round_id);
		//如果重复了4次之后就取消定时器
		if(this.round_id == 5){
			timer.cancel();
		}
	}
}