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1. Aggregation

The following sentences are designed to describe a class in terms of the aggregation of other classes.  Complete the sentences.

1.  A book is an aggregation of ________________________________________.

2.  A university degree course is an aggregation of __________________________.

3.  A railway route is an aggregation of __________________________________.

2. Generalisation-Specialisation

The following sentences are designed to describe classes in terms of their generalisation-specialisation relationship  Complete the sentences.

1.  A reference book is a specialisation of a _____________________________.

2.  An undergraduate degree is a specialisation of a  _______________________.

3.  A railway train is a specialisation of a  ________________________________.

4.  A bus is a generalisation of a _______________ and a __________________.

5.  A computer printer is a generalisation of a _________________________ and a 

______________________________.

3. Functional Dependencies

The following functional dependency diagram shows the relationship between attributes used to describe books stored in a number of different warehouses.  Which statement is NOT true:

1. given an ISBN number, you can uniquely determine the total number of copies of a book you have in stock

2. given an ISBN number, you can uniquely determine a book title

3. given a  book title you can not necessarily uniquely determine its ISBN number

4. given a quantity in stock you can not determine which book the quantity relates to

5.  you only need a warehouse number to determine the corresponding warehouse address.

4. Third Normal Form

Consider the following attributes for the class INVOICE LINE ITEM (a line which appears on an invoice):

INVOICE LINE ITEM (invoice-number, line-number, stock-number, invoice-date, ISBN, book-title, price)

Draw a functional dependency diagram and convert the attributes to third normal form.

(NB. Ignore any dependency between ISBN and book-title).

5. State Transition Diagram (STD)

Consider the following statechart diagram.

The diagram comprises states, initial states, terminal states, transitions, event, guards and actions.  State the type of the following:

1. book registered

2. non-reference book

3. returned

4. fine charged

5. update loan count

6. deleted from stock

7. no longer required

8. within due date

6. External Events

Which of the following are events in a banking system?

1. account opened
2. account goes overdrawn
3. clerk debits an account using a cheque
4. customer opens an account

7. Events

The following object life history model shows the events through which a book passes (from planning through to distribution).  The model as been developed for a book management system to be produced for a publisher.

Explain why it is difficult to add an event called 'take order' (which accepts orders for the book from retailer and can occur either during the planning stage of the book or during the production/distribution stage) and explain how you would handle this event.