操作系统生产者消费者问题（java用PV实现）

代码有四部分:

//https://www.cnblogs.com/wkfvawl/p/11529681.html
package myOperationSystem.ProducerAndConsumer;

public class Storage {
    private int[] mutex = { 1 }; // 互斥信号量mutex
    private int[] empty = { 10 }; // 同步信f非号量，表示空闲缓冲区的数量
    private int[] full = { 0 }; // 同步信号量，表示空闲缓冲区的数量
    public int[] count = { 0 }; // 计数器，结束线程
    private int huowu = 0; // 可用缓冲区的数量

    // p操作
    public synchronized void P(int[] num) {
        num[0]--;
        if (num[0] >= 0) {
            return;
        } else {

            try {
                System.out.println("t" + Thread.currentThread().getName() + " 被阻塞");
                wait();
                System.out.println("t" + Thread.currentThread().getName() + " 被唤醒");
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
        }
    }

    // v操作
    public synchronized void V(int[] num) {
        num[0]++;

        if (num[0] > 0) {
            return;
        } else {
            notify();
        }
    }

    // 生产者方法
    public synchronized void produce() {
        P(empty);
        P(mutex);

        try {
            Thread.sleep(500);
        } catch (InterruptedException e) {
            e.printStackTrace();
        }
        huowu++; // 生产完后货物++
        System.out.println(Thread.currentThread().getName() + " 把新产品放入缓冲区,库存还有： " + huowu);
        V(mutex);
        V(full);

    }

    // 消费者方法
    public synchronized void consume() {
        P(full);

        P(mutex);

        try {
            Thread.sleep(500);
        } catch (InterruptedException e) {
            e.printStackTrace();
        }

        huowu--; // 消费完后货物--
        System.out.println(Thread.currentThread().getName() + " 从缓冲区取走了物品,库存还有： " + huowu);
        V(mutex);
        V(empty);
    }

}

package myOperationSystem.ProducerAndConsumer;

public class Consumer implements Runnable {
    private Storage storage;

    public Consumer() {
    }

    public Consumer(Storage storage) {
        this.storage = storage;
    }

    @Override
    public void run() {
        while (true) {
            storage.count[0]++;

            if (storage.count[0] > 40) {
                break;
            }

            storage.consume();

            try {
                Thread.sleep(1500);
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
        }
    }
}

package myOperationSystem.ProducerAndConsumer;

public class Consumer implements Runnable {
    private Storage storage;

    public Consumer() {
    }

    public Consumer(Storage storage) {
        this.storage = storage;
    }

    @Override
    public void run() {
        while (true) {
            storage.count[0]++;

            if (storage.count[0] > 40) {
                break;
            }

            storage.consume();

            try {
                Thread.sleep(1500);
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
        }
    }
}

//https://www.cnblogs.com/wkfvawl/p/11538431.html
package myOperationSystem.ReaderAndWriter;

public class Main {
    public static void main(String[] args) {
        // 三个读者一个写者
        Book book = new Book();
        Reader reader1 = new Reader(book);
        Reader reader2 = new Reader(book);
        Reader reader3 = new Reader(book);
        Writer writer = new Writer(book);

        Thread r1 = new Thread(reader1, "读者1：");
        Thread r2 = new Thread(reader2, "读者2：");
        Thread r3 = new Thread(reader3, "读者3：");
        Thread w = new Thread(writer, "写者：");

        r1.start();
        r2.start();
        r3.start();
        w.start();
    }
}