public class Tongywo {
	public static void main(String[] args) {
		// TODO Auto-generated method stub
		Shangdian0 sd=new Shangdian0(100);
		Goumai0 no1=new Goumai0(70, sd, "No.1");
		Goumai0 no2=new Goumai0(80, sd, "No.2");
		
		no1.start();
		no2.start();
	}
}
class Shangdian0{
	
	int kucun=0;
	
	public Shangdian0(int kucun){
		
		this.kucun=kucun;
	}
	
	public synchronized void goumai(int i){
		
		if(i<kucun){
			
			kucun-=i;
			System.out.println(Thread.currentThread().getName()+"购买"+i+"本");
			System.out.println("商店剩余"+kucun+"本");
		}
		else{
			
			System.out.println("库存量不够");
		}
	}
}
class Goumai0 extends Thread{
	
	int i;
	Shangdian0 sd;
	
	public Goumai0(int i, Shangdian0 sd, String name){
		
		this.i=i;
		this.sd=sd;
		this.setName(name);
	}
	
	public void run(){
		
		sd.goumai(i);
	}
}原文地址:http://blog.csdn.net/wangxinxin_/article/details/46350389