What's the difference between abstraction and encapsulation?

Question

In interviews I have been asked to explain the difference between abstraction and encapsulation. My answer has been along the lines of

• Abstraction<

Answer 1

Encapsulation is basically denying the access to the internal implementation or knowledge about internals to the external world, while Abstraction is giving a generalized view of any implementation that helps the external world to interact with it

Answer 2

Difference between Abstraction and Encapsulation :-

Abstraction

1. Abstraction solves the problem in the design level.
2. Abstraction is used for hiding the unwanted data and giving relevant data.
3. Abstraction lets you focus on what the object does instead of how it does it.
4. Abstraction- Outer layout, used in terms of design. For Example:- Outer Look of a Mobile Phone, like it has a display screen and keypad buttons to dial a number.

Encapsulation

1. Encapsulation solves the problem in the implementation level.
2. Encapsulation means hiding the code and data into a single unit to protect the data from outside world.
3. Encapsulation means hiding the internal details or mechanics of how an object does something.
4. Encapsulation- Inner layout, used in terms of implementation. For Example:- Inner Implementation detail of a Mobile Phone, how keypad button and Display Screen are connect with each other using circuits.

Answer 3

Abstraction refers to the act of representing essential features without including the background details or explanations.

Encapsulation is a technique used for hiding the properties and behaviors of an object and allowing outside access only as appropriate. It prevents other objects from directly altering or accessing the properties or methods of the encapsulated object.

Difference between abstraction and encapsulation

1.Abstraction focuses on the outside view of an object (i.e. the interface) Encapsulation (information hiding) prevents clients from seeing it’s inside view, where the behavior of the abstraction is implemented.

2.Abstraction solves the problem in the design side while Encapsulation is the Implementation.

3.Encapsulation is the deliverable of Abstraction. Encapsulation barely talks about grouping up your abstraction to suit the developer needs.

Answer 4

In my opinion, both terms are related in some sense and sort of mixed into each other. "Encapsulation" provides a way to grouping related fields, methods in a class (or module) to wrap the related things together. As of that time, it provides data hiding in two ways;

1. Through access modifiers.

   Purely for hiding state of the class/object.

2. Abstracting some functionalities.

   a. Through interfaces/abstract classes, complex logic inside the encapsulated class or module can be abstracted/generalized to be used by outside.

   b. Through function signatures. Yes, even function signatures example of abstracting. Because callers only knows the signature and parameters (if any) and know nothing about how the function is carried out. It only cares of returned value.

Likewise, "Abstraction" might be think of a way of encapsulation in terms of grouping/wrapping the behaviour into an interface (or abstract class or might be even a normal class ).

Answer 5

Developer A, who is inherently utilising the concept of abstraction will use a module/library function/widget, concerned only with what it does (and what it will be used for) but not how it does it. The interface of that module/library function/widget (the 'levers' the Developer A is allowed to pull/push) is the personification of that abstraction.

Developer B, who is seeking to create such a module/function/widget will utilise the concept of encapsulation to ensure Developer A (and any other developer who uses the widget) can take advantage of the resulting abstraction. Developer B is most certainly concerned with how the widget does what it does.

TLDR;

• Abstraction - I care about what something does, but not how it does it.
• Encapsulation - I care about how something does what it does such that others only need to care about what it does.

(As a loose generalisation, to abstract something, you must encapsulate something else. And by encapsulating something, you have created an abstraction.)

Answer 6

Abstraction: Hiding the data. Encapsulation: Binding the data.