问答题

[Java程序7-1]
import java.util.*;
public class OrderList (1) {
private ArrayList＜Order＞ orders;
public OrderList0 {
this.orders = new ArrayList＜Order＞();
}
public void addOrder(Order orde0
this.orders.add(order);
}
public Iterator＜Order＞ iterator() {
return (2) ;
}
public iht getNumberOfOrders0 {
return this.orders.size();
}
}