Java Monitor Object在生产者消费者问题中的应用

package javaL.homework;
import java.util.ArrayList;
import java.util.List;
/**
* Producer and Consumer problem
* @author yaolei
*
*/
public class ProducerAndConsumer {
    public static void main(String[] args) {
        PCMonitor monitor = new PCMonitor();//monitor object
        Thread p1 = new Thread(new Producer(1, monitor));
        Thread p2 = new Thread(new Producer(2, monitor));
        Thread p3 = new Thread(new Producer(3, monitor));
        Thread c1 = new Thread(new Consumer(1, monitor));
        Thread c2 = new Thread(new Consumer(2, monitor));
        Thread c3 = new Thread(new Consumer(3, monitor));
        //start threads
        p1.start();
        p2.start();
        p3.start();
        c1.start();
        c2.start();
        c3.start();
    }
}

class Producer implements Runnable {
    private PCMonitor mtr = null;//the object which contains sharing resource
    private int producerNo; // the number of the Producer

    public Producer(int no, PCMonitor mtr) {
        this.mtr = mtr;
        this.producerNo = no;
    }

    @Override
    public void run() {
        // TODO Auto-generated method stub
        int productNo = 0;
        while (true) {
            Product p = new Product(producerNo,productNo++);
            try {
                mtr.put(p);
                System.out.println("Producer " + producerNo + " is producing product[" + p + "]");
                Thread.sleep(1000);
            } catch (Exception e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
        }
    }
}

class Consumer implements Runnable {
    private PCMonitor mtr = null;
    private int consumerNo;

    public Consumer(int no, PCMonitor mtr) {
        this.mtr = mtr;
        this.consumerNo = no;
    }

    @Override
    public void run() {
        // TODO Auto-generated method stub
        while (true) {
            try {
                Product p = mtr.get();
                System.out.println("Consumer " + consumerNo + " is consuming product[" + p + "]");
                Thread.sleep(1000);
            } catch (Exception e) {
                e.printStackTrace();
            }
        }
    }
}
class PCMonitor {
    private List<Product> items = new ArrayList<Product>();
    final static int MAX_COUNT = 20;//The max number of products in queue

    public synchronized void put(Product item) throws Exception {
        while (items.size()>=20)//while condition
            wait();
        items.add(item);
        notifyAll();// notify();
    }

    public synchronized Product get() throws Exception {
        while (items.isEmpty()) //while condition
            wait();
        Product item = items.remove(0);
        notifyAll();//notify()
        return item;
    }
}
class Product {
    private int id;
    private int producerId;

    public Product(int producerId,int id) {
        super();
        this.id = id;
        this.producerId = producerId;
    }
    public String toString() {
        return producerId+":"+id;
    }
}

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补充：软件开发 , Java ,