Question 5

Question 1

What are the benefits of specialisation and generalisation

Answer 1

Any changes made to the generalisation will follow down to the specialisations and will only need to be carried out once

Question 2

What is the difference between communication and sequence diagrams?

Answer 2

The two show the same information. The time ordering of messages is clear in a sequence diagram time passes by as you travel down the page. Some form of numbering is needed in a communication diagram to show the time ordering of messages and the numbering can become complicated.

Question 3

What does GRASP stand for?

Answer 3

General responsibility assignment software patterns

Question 4

Grasp expert

Answer 4

Assigns responsibility to a class that has the information necessary to fulfil that responsibility.

Question 5

Grasp creator

Answer 5

To assign responsibility for creating objects

Question 6

Law of Demeter

Answer 6

Each unit should have only limited knowledge about other units: only units “closely” related to the current unit.
Each unit should only talk to its friends; don’t talk to strangers.
Only talk to your immediate friends.
The fundamental notion is that a given object should assume as little as possible about the structure or properties of anything else (including its subcomponents), in accordance with the principle of “information hiding”.