线程不安全三大案例_不安全的集合

package com.qiliang.demo13_线程同步安全;

import java.util.ArrayList;

// 线程不安全的集合
public class UnSafeList {
    public static void main(String[] args) throws InterruptedException {
        ArrayList<String> list = new ArrayList<>();
        for (int i = 0; i < 10000; i++) {
            new Thread(()->{
                list.add(Thread.currentThread().getName());
            }).start();
        }
        Thread.sleep(3000);   // 9997  i=10000
        System.out.println(list.size()); // 918  i=1000
    }
}