Encapsulation

Abstract

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• Group related variables and functions together to create a OOP class
• This class manages how data is hidden and allow access through class itself or its methods, ensuring data safety

Tell, Don’t Ask

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• A principle in OOP that tells objects what to do rather than asking them about their internal state and then making decisions based on that state. This promotes encapsulation, reduces dependencies, and enhances code maintainability and readability. As a result, code is less likely to break when the internal state of objects changes

Encapsulation

By instructing objects on what to do, you ensure they encapsulate their data and provide a well-defined interface for interaction.

Reduce dependencies

Reducing the dependencies between objects leads to a more modular and flexible design, where changes in one part of the system have minimal impact on other parts.

Improves readability

It makes the code easier to understand as it focuses on actions and responsibilities rather than on the internal states of objects.

”Has-a” Relationship

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• Also known as Composition
• “Class A has a Class B,” it means that Class A contains an instance of Class B as one of its members or attributes. This relationship, known as composition, is achieved by Class A holding a reference to an object of Class B

A less abstracted explanation

Consider a class Car and a class Engine. In this case, a Car has an Engine, meaning that a Car object contains an instance of the Engine class.

This allows for flexible designs as the Engine class can be easily replaced with another class that exhibits the same behaviour. It also promotes encapsulation by keeping related functionalities within the classes responsible for them.

“Has-a” Relationship is employed when one class needs to utilise the functionality of another class without inheriting from it, resulting in a more modular and adaptable design.