【线程安全】内存可见性问题及解决方案

1. 关于内存可见性的一段代码

import java.util.Scanner;
public class ThreadDemo {
    public static int count = 0;
    public static void main(String[] args) throws InterruptedException {
        Thread t1 = new Thread(() -> {
            while (count == 0) {

            }
            System.out.println("t1 线程结束!");
        });
        Thread t2 = new Thread(() -> {
            Scanner scanner = new Scanner(System.in);
            count = scanner.nextInt();
            System.out.println("t2 线程结束! count = " + count);
        });
        t1.start();