3. Basic principles and terminology (OO analysis and design)

Question 1

Encapsulation

Answer 1

Bundling together of data and behaviour so they are inseparable
Information hiding is the process of hiding all details of the object except those strictly necessary to the outside

Question 2

Inheritance

Answer 2

Subclasses ‘inherit’ properties (attributes and operations) from the superclass

Question 3

Polymorphism

Answer 3

Ability of different objects within the same inheritance hierarchy to act appropriately to the same message
e.g. Superclass animal with subclasses of tiger, elephant, mouse, and there is a operation makeNoise (each subclass will have the makeNoise operation but in a different way and a different noise)