生产者－消费者问题

java线程的生命周期

/**
 * 公共资源类
 */
public class PublicResource {

    private int number = 0;

    /**
     * 增加公共资源
     */
    public synchronized void increase() {
        while (number >= 3) {
            try {
                wait();
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
        }
        number++;
        System.out.println(number);
        notify();
    }

    /**
     * 减少公共资源
     */
    public synchronized void decrease() {
        while (number == 0) {
            try {
                wait();
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
        }
        number--;
        System.out.println(number);
        notify();
    }

}

public class ProducerConsumer {

    /**
     * 生产者线程，负责生产公共资源
     */
    public static class ProducerThread implements Runnable {
        private PublicResource resource;

        public ProducerThread(PublicResource resource) {
            this.resource = resource;
        }

        @Override
        public void run() {
            while(true){
                try {
                    Thread.sleep((long) (Math.random() * 1000));
                } catch (InterruptedException e) {
                    e.printStackTrace();
                }
                resource.increase();
            }
        }
    }


    /**
     * 消费者线程，
     * 负责消费公共资源
     */
    public static class ConsumerThread implements Runnable {
        private PublicResource resource;

        public ConsumerThread(PublicResource resource) {
            this.resource = resource;
        }

        @Override
        public void run() {
            while(true){
                try {
                    Thread.sleep((long) (Math.random() * 1000));
                } catch (InterruptedException e) {
                    e.printStackTrace();
                }
                resource.decrease();
            }
        }
    }

    public static void main(String[] args) {
        PublicResource resource = new PublicResource();

        new Thread(new ProducerThread(resource)).start();
        new Thread(new ConsumerThread(resource)).start();
    }
}