Task 4 Develop a class diagram for following description: Develop a class diagram for following description: The telephone agent uses an order registry and customer catalog to obtain access to an...

Extracted text: Task 4 Develop a class diagram for following description: Develop a class diagram for following description: The telephone agent uses an order registry and customer catalog to obtain access to an order & a customer respectively. The order registry uses an order number as a qualifier to select particular order instance. A customer catalog uses customer name and phone number as a qualifier to select particular customer. The attributes of an order are the order numbers and time when it is placed. The order consists of many items. An item has item_number, a quantity, unit price. It also has reference to catalog item which represents listing. When an order is cancelled or corrmitted, it cancels or commits each of its items first. When an order's total price method is invoked, the order calls the total price method of each of items and returns the sum.