Encapsulation & Polymorphism

Encapsulation

Encapsulation in object-oriented programming is a principle that concerns how data inside the class can be accessed or changed.

Setters and getters

A setter is a special type of method that sets one of the attributes equal to a specific value.
A getter is a special type of method that obtains the value of one of the attributes of the object.

Encapsulation

Each attribute can only be accessed or modified by methods that are set (encapsulated) when defining the class.
- This is also known as 'information hiding'.
The use of these methods protects the data in the class instance from being tampered with.

Different instances

An instance of a class should not be able to alter the data of another instance of the same class.
For example, if you have an instance of a car class called “car1”, its methods should not be able to alter the attributes of another instance of the car class that is also running.

Polymorphism

In object-oriented programming, polymorphism is when a subclass alters its inherited methods in two ways: by overloading or overriding.

Overloading

Overloading is when a method is defined in the subclass that has the same name, but different arguments to a method defined in the superclass.
The method might also have a different return type.
For example, a shape superclass might have an area calculating function.
- The subclass circle could have the function area(radius), whereas a triangle subclass could have the function area(base,height).

Overriding

Overriding is when a method is redefined in the subclass with the same name and same arguments.
The method that is defined in the subclass overrides the method defined in the super class.

1Components of a Computer

1.1Structure & Function of the Processor

1.1.1Structure of the CPU

1.1.2Fetch, Decode, Execute Cycle

1.1.3Factors Affecting CPU Performance

1.1.4CPU Architecture

1.2Types of Processors

1.2.1CISC & RISC

1.2.2Multicore & Parallel Cores

1.3Input, Output & Storage

1.3.1Computer Systems

1.3.2Magnetic Storage

1.3.3Optical Storage

1.3.4Types of Optical Storage

1.3.5Types of Memory

1.3.6Flash Memory

1.3.7Virtual Memory

2Software & Software Development

3Exchanging Data

4Data Types, Data Structures & Algorithms

4.1Data Types

4.1.1Data Types

4.1.2Arrays & Strings

4.1.3Representing Numbers

4.1.4Binary Arithmetic

4.1.5Hexadecimal

4.1.6Converting Binary Numbers

4.1.7Floating Points in Binary

4.1.8Floating Point Arithmetic

4.1.9Bitwise Manipulation

4.1.10Character Sets

4.2Data Structures

4.2.1Arrays, Linked Lists & Queues

4.2.2Graphs, Hash Tables & Stacks

4.2.3Trees

4.3Boolean Algebra

4.3.1Computational Logic

4.3.2Boolean Logic

4.3.3Karnaugh Maps

4.3.4Boolean Identities

4.3.5Flip Flops & Adder Circuits

5Legal, Moral, Cultural & Ethical Issues

5.1Computing Related Legislation

5.1.1Data Protection Act (1998)

5.1.2Computer Misuse Act (1990)

5.1.3Copyright Designs and Patents Act (1988)

5.1.4Regulation of Investigatory Powers Act (2000)

5.2Moral & Ethical Issues

5.2.1Online Activity Tracking

5.2.2Censorship

5.2.3Cultural Issues

5.2.4Environmental Issues

5.2.5Layout, Colour Paradigms & Character Sets

6Elements of Computational Thinking

6.1Thinking Abstractly

6.1.1Abstraction

6.2Thinking Procedurally

6.2.1Decomposition

6.3Thinking Logically

6.3.1Pseudocode & Flow Diagrams

7Problem Solving & Programming

7.1Programming Techniques

7.1.1Programming Fundamentals

7.1.2Modularity

7.2Programming Construction

7.2.1Integrated Development Environments

7.2.2Testing

8Algorithms

8.1Algorithms

8.1.1Interpreting, Correcting & Completing Algorithm

8.1.2Sort Algorithms

8.1.3Insertion & Merge Sort

8.1.4Search Algorithms

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