有n个赛车，让它们都在起跑线上就绪后，同时出发，用Java多线程的技术把这种情况写出来

import java.util.concurrent.CyclicBarrier;
import java.util.concurrent.SynchronousQueue;
import java.util.concurrent.ThreadPoolExecutor;
import java.util.concurrent.TimeUnit;

public class Application {

    private static final int THREAD_COUNT = 30;
　　 //CountDownLatch 也可以，比较投机取巧的方法，不是最优解，最优解请参考 http://wksora.github.io/06-2014/car-competion.html
    private static final CyclicBarrier ready = new CyclicBarrier(THREAD_COUNT);

    public static void main(String[] args) {
        ThreadPoolExecutor pool = new ThreadPoolExecutor(THREAD_COUNT, THREAD_COUNT, 60, TimeUnit.SECONDS, new SynchronousQueue<>());
        for (int i = 0; i < THREAD_COUNT; i++) {
            pool.execute(new Car(i, ready));
        }
    }
}

import java.util.concurrent.BrokenBarrierException;
import java.util.concurrent.CyclicBarrier;

public class Car implements Runnable {
    private int index;
    private final CyclicBarrier ready;

    public Car(int index, CyclicBarrier ready) {
        this.index = index;
        this.ready = ready;
    }

    @Override
    public void run() {
        try {
            System.out.println("Car Index " + this.index + " ready");
            ready.await();
        } catch (InterruptedException | BrokenBarrierException e) {
            e.printStackTrace();
        } finally {
            System.out.println("Car Index " + this.index + " run");
        }
    }
}