使用countDownLatch导致的线程安全问题,线程不安全的List-ArrayList,线程安全的List-CopyOnWriteArrayList
示例代码packagecom.example.demo.service;importjava.util.ArrayList;importjava.util.List;importjava.util.concurrent.CountDownLatch;importjava.util.concurrent.ExecutorService;importjava.util.concurrent.Execu