invoice.java

点菜系统

package chapter1;
import javax.swing.JOptionPane;
public class Invoice extends SortedList{
	//定义与提货清单关联的存货清单
	private Inventory inventory;
	//提货清单构造函数
	public Invoice(Inventory _inventory){
    //调用父类SortedList的构造函数
    super(new ItemComparer());
    inventory = _inventory;
}
 //在提货清单中增加提货条目，同时在存货清单中对应的存货
//条目上减少用户输入的商品数量
public void addItem(String _ID,int _number) {
	InventoryItem item = inventory.getPart(_ID);
	if ((item !=null) && (item.units >= _number) && (_number >= 0) && !isFull()){
		item.remove(_number);
		add(new InvoiceItem(item,_number));
	}else
	  JOptionPane.showMessageDialog(null,"列表满、项没有找到或者商品已经订完！","警告",JOptionPane.ERROR_MESSAGE);
	  System.out.println("List full,item not found or invalid units");
}
//根据用户输入的id，在提货清单上删除提货条目
public void delItem(String _ID)
{
	int index = indexOf(new Item(_ID));
	if (index >= 0)
	    delete(index);
}
//返回提货清单上商品的价格总和
public double getTotal(){
	double total = 0.0;
	for(int i = 0; i < getSize(); i++)
	total += ((InvoiceItem) get(i)).total;
	return total;
}
//以字符串的形式返回提货清单
public String toString() {
	 return"提货清单：" + Util.dollar(getTotal()) + super.toString();
	 }

}