Project 3 Design

Due Date

11:59pm, Sunday, April 3, 2005
No late designs accepted

Objective

The objective of this assignment is to make sure that you begin thinking about your project in a serious way early. This will not only give you experience doing design work, but will help you anticipate the number of hours that you'll need to set aside to be able to complete the project.

The Assignment

Part I

Project 3 introduces two new car types to be rented by R & W. With 3 types of cars and 2 types of customer cards, calculating the rental fees and the insurance fees can become cumbersome. This is especially true if you consider (as you should) that R & W may introduce more car types and more customer card types in the future.

The first part of your assignment is to design a way to perform the calculations which is easily extensible for more car and customer card types. The naive solution of nested "if/else" statements shown below is NOT acceptable since adding more car and/or customer card types adds more code. Similarly, a combination of "if/else" and/or "switch/case" statements is also NOT acceptable for the same reason.

// this code is NOT extensible and NOT acceptable if (car type is ECONOMY) { if (card type is GOLD) do ECONOMY/GOLD calculations else if (card type is PLATINUM) do ECONOMY/PLATINUM calculations } else if (car type is MIDSIZE) { if (card type is GOLD) do MIDSIZE/GOLD calculations else if (card type is PLATINUM) do MIDSIZE/PLATINUM calculations } else if (car type is LUXURY) { if (card type is GOLD) do LUXURY/GOLD calculations else if (card type is PLATINUM) do LUXURY/PLATINUM calculations }

Part II

PLATINUM customers may now rent multiple cars simultaneously. When printing the list of customers, you must print all cars that rented by each customer. When printing the list of cars, you must print the customer who has rented the car. These two requirements mandate a "bi-directional association" between the cars and the customers. I.e. the car "knows" about the customer who rented it and the the customer "know" about the cars he has rented.

Part II of your assignment is to explain how you plan to implement this bi-directional association. NOTE that keeping customer information in the car class or keeping car information in the customer class is NOT acceptable. You are asked to design this bi-directional car/customer association without storing any reference to the car, info about the car, or car vector index/pointer in the customer AND without storing any reference to the customer, customer info, or customer vector index/pointer in the car. Such an approach duplicates information and code.

A template for your design document, p3design.txt, is provided in Ms. Wortman's public directory. Copy that file /afs/umbc.edu/users/d/a/dana3/pub/CMSC202/p3/p3design.txt to your local directory and fill in the necessary information. Submit your modified p3design.txt file to complete this assignment.

Grading

You p3design.txt file will count as 10% of your project 3 grade (part of the Correctness). If this file is not submitted by its due date, or if you submit a new version after its due date, you will lose all 10 points.

Your p3design.txt file will be compared to the header file or files that you submit when Project 3 is due. Minor changes to the design are allowed. A minor change might be the addition of another function or two or changing the way in which one or two parameters are passed.

If there are major changes between the design document and the header files that are part of the final project, you will lose 5 points. This would indicate that you didn't give sufficient thought to your design before beginning the implementation.

Last Modified: Tuesday, 29-Mar-2005 15:29:43 EST