Java 关于线程虚假唤醒问题

package test1;

/**
 * 虚假唤醒
 *
 * 为什么 if会出现虚假唤醒 -> 因为if只会执行一次，执行完会接着向下执行if（）外边的
 * 而while不会，直到条件满足才会向下执行while（）外边的
 *
 */
public class main {
    public static void main(String[] args) {
        PC1 pc1 = new PC1();

        new Thread(() -> {
            try {
                for (int i = 0; i < 10; i++) {
                    pc1.producer();
                }
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
        }, "A").start();

        new Thread(() -> {
            try {
                for (int i = 0; i < 10; i++) {
                    pc1.consumer();
                }
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
        }, "A").start();

        new Thread(() -> {
            try {
                for (int i = 0; i < 10; i++) {
                    pc1.producer();
                }
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
        }, "B").start();

        new Thread(() -> {
            try {
                for (int i = 0; i < 10; i++) {
                    pc1.consumer();
                }
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
        }, "B").start();
    }
}


/**
 * producer
 * consumer
 *
 * @author Sage
 * @date 2021/10/19
 */
class PC1{

    private int goods = 0;

    /**
     * 生产商
     */
    public synchronized void producer() throws InterruptedException {
        while (goods != 0) {
            this.wait();
        }

        System.out.println(Thread.currentThread().getName() + "=>" + "生产了一个货物");
        goods++;
        this.notifyAll();
    }

    /**
     * 消费者
     */
    public synchronized void consumer() throws InterruptedException {
        while (goods == 0) {
            this.wait();
        }

        System.out.println(Thread.currentThread().getName() + "=>" + "消费了一个货物");
        goods--;
        this.notifyAll();
    }
}