import java.util.concurrent.CountDownLatch;

/**
 * Created by zyBourn on 15/12/25.
 */
public class Entity {
    public static void main(String[] args) {
        //倒数计时 每执行一次countDown则减一次，总数减完后执行
        CountDownLatch countDownLatch=new CountDownLatch(2);
        new Racer(countDownLatch,"A").start();
        new Racer(countDownLatch,"B").start();
        new Racer(countDownLatch,"C").start();
        new Racer(countDownLatch,"D").start();
        for (int i=0;i<3;i++){
            try{
                Thread.sleep(1000);
            }catch (InterruptedException e){
                e.printStackTrace();
            }
            System.out.println(i);
            countDownLatch.countDown();
            if (i==2)
                System.out.println("Start");
        }
    }
}
class Racer extends Thread{
    private CountDownLatch countDownLatch;
    public Racer(CountDownLatch countDownLatch,String name){
        setName(name);
        this.countDownLatch=countDownLatch;
    }
    public void run(){
        try{
            countDownLatch.await();
            for(int i = 0;i<3;i++)
                System.out.println(getName()+"=:"+i);
        }catch (InterruptedException e){
            e.printStackTrace();
        }
    }
}