publicclassPayment{publicintsku=100;publicstaticvoidmain(String[]args){Paymentp=newPayment();Order1o1=newOrder1(p);Order2o2=newOrder2(p);o1.start();o2.start();}}classOrder1extendsThread{Paymentp;publicOrder1(Paymentp){this.p=p;}@Overridepublicvoidrun()//重写run(){synchronized(p)//对象p加锁{p.sku-=1;System.out.println("剩余库存："+p.sku);}}}classOrder2extendsThread{Paymentp;publicOrder2(Paymentp){this.p=p;}@Overridepublicvoidrun(){synchronized(p){p.sku-=1;System.out.println("剩余库存："+p.sku);}}}