The basic system has to offer the following options:

1. Exit the program

2. Enter new customer

The program prompts for the details of a new customer, assigns a unique customer number to the customer and creates a new entry in the database. Also, the new customer becomes the current customer.

3. Search for customer

The program prompts for a customer number and searches the database for the customer's record in the database. If it exists, the program displays the customer's details and makes the customer the current customer.

4. Enter new contact for current customer

The program prompts for the details of a new contact for the current customer interactively and creates a new entry in the database.

5. Show next contact of current customer

The user can step forward through the list of contacts of the current customer and the contact details are displayed.

6. Show previous contact of current customer

The user can step backwards through the list of contacts of the current customer and the contact details are displayed.

7. Help

Provide user instructions.

Save and load

Additional functionality:

1. Save database

This option allows the user to store the contents of the database into ASCII text files on the hard drive. The user should be able to choose a filename.

2. Load database

This option allows the user to load the database from an ASCII text file. The user should be able to specify a file name. If the file does not exist, the program will print an error message.

Additional search

Additional functionality:

1. List customer contacts

The program will output an error message if no contact is found in the database; otherwise it displays a list of all the contacts of the current customer.

2. Search for an order number

The program will output an error message if the order number is not found in the database, otherwise it displays the details of the specific order.

3. Search for a reference number

The program will output an error message if the reference number is not found in the database, otherwise it displays the details of the specific return transaction.

Graphical user interface

Additional functionality:

All operator interactions are carried out using a graphical user interface.

3.4.2 Design

• Use of appropriate classes
• Complexity of data structure used
• Following the style guide
• Quality of design
• Use of inheritance
• Use of encapsulation

3.4.3 Documentation

• Use cases , use case templates
• Class diagrams
• Class model, relationship
• Sequence diagrams
• Description of the data structure
• Description of the file format used
• Test documentation, User Screens
• GUI documentation