cs 1.2 (OOP) (ALEVEL)

Question 1

Objects

Answer 1

containers of data and instructions(used instead of variables/constants)
new objects created from classes
creating object = instantiation

Question 2

Class

Answer 2

specify what properties (data) and methods (instruction) objects of their type with have

Question 3

Private methods/property

Answer 3

only accessed from within an object

Question 4

Public methods

Answer 4

allow an interface for accessing/modifying a class’ private properties

Question 5

encapsulation

Answer 5

process of combining methods and procedures to form an object, object is said to encapsulate its contents, forming a single entity which encompasses all of object properties/ methods

Question 6

Inheritance

Answer 6

A class can inherit another class, inheritance allows one class to share the properties of another class while having its own properties and methods too

Question 7

Polymorphism

Answer 7

occurs when objects are processed differently depending on their class

Question 8

Overriding

Answer 8

overridden method has the same name as a method in an inherited class but different implementation

Question 9

association

Answer 9

if two objects associated, they can be described as having a ‘has a’ relationship. e.g. objects of classes Car and Driver can be associated as a car has a driver
The container object holds the associated object as one of its properties (fields)

Question 10

aggregation - association

Answer 10

when an object is associated with another by aggregation, it will still exist if its containing object is destroyed

Question 11

composition - association

Answer 11

if two object associated by composition and the containing object is destroyed, associated object is also destroyed

Question 12

why use OOP?

Answer 12

has a clear structure, makes developing and testing programs easier for developers, allows large projects to be divided among a team, use of classes allows code to be reused throughout program, improves space efficiency of code