public class SharedVariableExample {
    private static volatile boolean flag = false;

    public static void main(String[] args) {
        // 生产者线程
        Thread producer = new Thread(() -> {
            try{
                Thread.sleep(2000);
            }catch (InterruptedException e){
                e.printStackTrace();
            }
            // 修改共享变量
            flag = true;
            System.out.println("Producer: Flag is set to true.");
        });

        // 消费者线程
        Thread consumer = new Thread(() -> {
            while (!flag){
                // 等待共享变量被修改
            }
            System.out.println("Consumer: Flag is now true.");
        });

        producer.start();
        consumer.start();

    }
}