Java中的多个消费者生产者

Question

我试图为消费者创建2个线程，为生产者创建2个线程。所有4个线程都在争夺一种资源。其中两个正在尝试从资源中消耗，其中两个正在尝试生产。

下面是代码

package com.threading;

import java.util.ArrayList;
import java.util.List;

public class TestConsumerProducer2 {

    protected static int maxSize = 2;

    static class Consumer implements Runnable {
        List<Integer> goods;

        public Consumer(List<Integer> goods) {
            this.goods = goods;
        }

        public void consume() {
            synchronized (goods) {

                if (goods.size() <= 0) {
                    try {
                        goods.wait();
                    } catch (InterruptedException e) {
                        // TODO Auto-generated catch block
                        e.printStackTrace();
                    }
                }
                System.out.println(Thread.currentThread().getName() + " >>>> consuming >>>" + goods.remove(0));
                goods.notifyAll();
            }
        }

        @Override
        public void run() {
            for (int i = 0; i < 10; i++) {
                consume();
                try {
                    Thread.currentThread().sleep(100);
                } catch (InterruptedException e) {
                    // TODO Auto-generated catch block
                    e.printStackTrace();
                }
            }
        }
    }

    static class Producer implements Runnable {
        List<Integer> goods;

        public Producer(List<Integer> goods) {
            this.goods = goods;
        }

        public void produce(int i) {
            synchronized (goods) {

                if (goods.size() >= maxSize) {
                    try {
                        goods.wait();
                    } catch (InterruptedException e) {
                        // TODO Auto-generated catch block
                        e.printStackTrace();
                    }
                }
                System.out.println(Thread.currentThread().getName() + ">>> producing >> " + i);
                goods.add(i);
                goods.notifyAll();
            }
        }

        @Override
        public void run() {
            // TODO Auto-generated method stub
            for (int i = 0; i < 10; i++) {
                produce(i);
                try {
                    Thread.currentThread().sleep(100);
                } catch (InterruptedException e) {
                    // TODO Auto-generated catch block
                    e.printStackTrace();
                }
            }
        }
    }

    public static void main(String[] args) {
        List<Integer> goods = new ArrayList<>();
        Consumer consumer = new Consumer(goods);
        Producer producer = new Producer(goods);
        Thread consumerWorker1 = new Thread(consumer);
        Thread consumerWorker2 = new Thread(consumer);

        Thread prroducerWorker1 = new Thread(producer);
        Thread prroducerWorker2 = new Thread(producer);

        consumerWorker1.start();
        consumerWorker2.start();
        prroducerWorker1.start();
        prroducerWorker2.start();

        try {
            consumerWorker1.join();
            consumerWorker2.join();
            prroducerWorker1.join();
            prroducerWorker2.join();
        } catch (InterruptedException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }

        System.out.println("Job completed >>>>");
    }
}

输出程序

Thread-2 >>>生产>> 0

线程-1 >>>>消耗>>> 0

Thread-3 >>>制作>> 0

线程“Thread-0”中的异常java.lang.IndexOutOfBoundsException：索引：0，大小：0，位于java.util.ArrayList.remove（ArrayList.java:496）的java.util.ArrayList.rangeCheck（ArrayList.java:657） ）com.threading.TestConsumerProducer2 $ Consumer.consume（TestConsumerProducer2.java:27）at com.threading.TestConsumerProducer2 $ Consumer.run（TestConsumerProducer2.java:35）at java.lang.Thread.run（Thread.java:748） Thread-2 >>>制作>> 1

线程-1 >>>>消耗>>> 0

Thread-3 >>>制作>> 1

线程-1 >>>>消耗>>> 1

Thread-2 >>>制作>> 2

线程-1 >>>>消耗>>> 1

Thread-3 >>>制作>> 2

线程-1 >>>>消耗>>> 2

Thread-2 >>>制作>> 3

线程-1 >>>>消耗>>> 2

Thread-2 >>>生产>> 4

Thread-3 >>>制作>> 3

线程-1 >>>>消费>>> 3

Thread-2 >>>生产>> 5

线程-1 >>>>消费>>> 4

Thread-3 >>>制作>> 4

线程-1 >>>>消费>>> 3

Thread-2 >>>制作>> 6 Thread-1 >>>>消费>>> 5

Thread-2 >>>生产>> 7

Thread-3 >>>制作>> 5

问题陈述：为什么没有一个线程执行10次？代码中的死锁情况在哪里？当Goods对象被消费者线程锁定并且size <= 0时，为什么会出现IndexOutOfBoundsException它应该进入等待状态？