一、整体代码

ThreadDemo.java

public  class ThreadDemo { public static void main(String[] args) { Godown godown = new Godown(0); Consumer c1 = new Consumer(50, godown); Consumer c2 = new Consumer(20, godown); Consumer c3 = new Consumer(30, godown); Producer p1 = new Producer(10, godown); Producer p2 = new Producer(10, godown); Producer p3 = new Producer(10, godown); Producer p4 = new Producer(10, godown); Producer p5 = new Producer(10, godown); Producer p6 = new Producer(10, godown); Producer p7 = new Producer(80, godown); c1.start(); c2.start(); c3.start(); p1.start(); p2.start(); p3.start(); p4.start(); p5.start(); p6.start(); p7.start(); }
} /**
* 仓库
*/
class Godown { public static final int max_size = 100; //最大库存量 public int curnum;     //当前库存量 Godown() { } Godown(int curnum) { this.curnum = curnum; } /** * 生产指定数量的产品 * * @param neednum */ public synchronized void produce(int neednum) { //测试是否需要生产 while (neednum + curnum > max_size) { System.out.println("要生产的产品数量" + neednum + "超过剩余库存量" + (max_size - curnum) + "，暂时不能执行生产任务!"); try { //当前的生产线程等待 wait(); } catch (InterruptedException e) { e.printStackTrace(); } } //满足生产条件，则进行生产，这里简单的更改当前库存量 curnum += neednum; System.out.println("已经生产了" + neednum + "个产品，现仓储量为" + curnum); //唤醒在此对象监视器上等待的所有线程 notifyAll(); } /** * 消费指定数量的产品 * * @param neednum */ public synchronized void consume(int neednum) { //测试是否可消费 while (curnum < neednum) { try { //当前的生产线程等待 wait(); } catch (InterruptedException e) { e.printStackTrace(); } } //满足消费条件，则进行消费，这里简单的更改当前库存量 curnum -= neednum; System.out.println("已经消费了" + neednum + "个产品，现仓储量为" + curnum); //唤醒在此对象监视器上等待的所有线程 notifyAll(); }
} /**
* 生产者
*/
class Producer extends Thread { private int neednum;                //生产产品的数量 private Godown godown;            //仓库 Producer(int neednum, Godown godown) { this.neednum = neednum; this.godown = godown; } public void run() { //生产指定数量的产品 godown.produce(neednum); }
} /**
* 消费者
*/
class Consumer extends Thread { private int neednum;                //生产产品的数量 private Godown godown;            //仓库 Consumer(int neednum, Godown godown) { this.neednum = neednum; this.godown = godown; } public void run() { //消费指定数量的产品 godown.consume(neednum); }
}

二、解释