Class Diagram for the Amazon Locker Service

We’ll create the class diagram for the Amazon Locker service. In the class diagram, we will first design the system’s classes and then identify the relationship between classes according to the Amazon Locker service problem requirements.

Components of an Amazon Locker service

In this section, we’ll define the classes for an Amazon Locker service. As mentioned, we are following the bottom-up approach to design a class diagram for the Amazon Locker service.

Customer

The Customer class models an Amazon user interacting with the locker system to place orders, initiate returns, and receive notifications. It holds identifying and contact information, and provides methods to request orders and returns, supporting all customer-facing workflows.

DeliveryPerson

The DeliveryPerson class models the logistics staff member who delivers packages to lockers and collects returned items. It uses a unique identifier for each delivery person and provides methods to perform deliveries, pick up returns, and process return notifications. Personal contact information is not stored, keeping the class simple and focused on system operations.

Item

The Item class represents an individual product that can be part of a customer’s order. Each item has a unique identifier (itemId), a descriptive name, and a quantity specifying how many units are included in the order. This class allows the system to keep track of each product purchased, whether for delivery or return, and supports the packaging and order fulfilment processes.

The class representation is shown below:

Order

The Order class models a complete transaction initiated by a customer. It includes a unique order identifier (orderId), a reference to the customer (customerId), a list of items (items), and a delivery location, which is typically an instance of LockerLocation. Orders are the starting point for both delivery and return workflows and serve as the central record for tracking the status of ...