如何编写具有关联类的UML类图

Question

       0..*                    1..*
+-------+                       +--------+      
|Invoice|_______________________|Products|
+-------+           |           +--------+
|inID   |           |           |proID   |
|inDate |           |           | Qty    |
+-------+           |           | Price  |
                    |           +--------+
               +-----------+
               |LineProduct|
               +-----------+
               | Qty       |
               | salePrice |
               +-----------+

这个编码对于上面的类图是否正确？

Class Invoice 
{
 inID:int;
 inDate:Date;
}

Class LineProduct 
{
 Qty:int;
 salePrice:int;
 //inID:int;  <-- this is what I did but I am wrong 
 //prodID:int; <-- this is what I did but I am wrong 
}

Class Products
{
 prodID:int;
 Qty:int;
 Price:int;
}

现在，例如，如果发票包含两个产品，我必须将对象实例传递给DB函数，例如

invoiceTable.saveInvoice(invoice:Invoice);
lineproductTable.saveLine( product instance 1 );
lineproductTable.saveLine( product instance 2 );

现在又一次混淆了行产品表将包含inID和proID列，但是如何传递一个具有inID和prod ID的对象？

PS：对不起，我被困在低位代表我无法张贴图片并解释我的困惑

Answer 1

我认为你首先做对了。

//inID:int;  <-- this is what I did but I am wrong 
//prodID:int; <-- this is what I did but I am wrong 

取消注释这些行。这是将产品与发票相关联的唯一方法。