多线程--生产者消费者--简单例子

package com.lm.multest;

import java.util.concurrent.locks.Condition;
import java.util.concurrent.locks.Lock;
import java.util.concurrent.locks.ReentrantLock;

class Resource {
	private int num;
	private String name;
	private boolean flag = false;
	Lock lock = new ReentrantLock();
	Condition notFull = lock.newCondition();
	Condition notEmpty = lock.newCondition();

	public void set(String n) {
		lock.lock();
		try {
			while (flag)
				notFull.await();
			this.name = n + num++;
			System.out.println(Thread.currentThread().getName() + "..生产..."
					+ name);
			flag = true;
			notEmpty.signalAll();
		} catch (InterruptedException e) {
			e.printStackTrace();
		} finally {
			lock.unlock();
		}

	}

	public void out() {
		lock.lock();
		try {
			while (!flag)
				notEmpty.await();
			System.out.println(Thread.currentThread().getName() + "..消费.."
					+ name);
			flag = false;
			notFull.signalAll();
		} catch (InterruptedException e) {
			e.printStackTrace();
		} finally {
			lock.unlock();
		}

	}
}

class Producer implements Runnable {

	private Resource res;

	Producer(Resource res) {
		this.res = res;
	}

	@Override
	public void run() {
		while (true)
			res.set("商品");
	}

}

class Consumer implements Runnable {
	private Resource res;

	Consumer(Resource res) {
		this.res = res;
	}

	public void run() {
		while (true)
			res.out();
	}
}

public class ProducerConsumerDemo {

	public static void main(String[] args) {
		Resource r = new Resource();
		Producer p = new Producer(r);
		Consumer c = new Consumer(r);

		Thread th1 = new Thread(p);
		Thread th2 = new Thread(c);
		Thread th3 = new Thread(p);
		Thread th4 = new Thread(c);

		th1.start();
		th2.start();
		th3.start();
		th4.start();
	}

}