encapsulation vs abstraction real world example

Question

For an example of encapsulation i can think of the interaction between a user and a mobile phone. The user does not need to know the internal working of the mobile phone to

Answer 1

Abstraction

It is used to manage complexities of OOPs. By using this property we can provide essential features of an object to the user without including its background explanations. For example, when sending message to a friend we simply write the message, say "hiiii" and press "send" and the message gets delivered to its destination (her,friend). Here we see abstraction at work, ie we are less concerned with the internal working of mobile that is responsible for sending and receiving message

Answer 2

Encapsulation is to hide the variables or something inside a class, preventing unauthorized parties to use. So the public methods like getter and setter access it and the other classes call these methods for accessing

Abstraction involves the facility to define objects that represent abstract "actors" that can perform work, report on and change their state, and "communicate" with other objects in the system.

Consider the below real time example:

Encapsulation: As a driver you know how to start the car by pressing the start button and internal details of the starting operations are hidden from you. So the entire starting process is hidden from you otherwise we can tell starting operation is encapsulated from you.

OR

The driving wheel is encapsulated the process of rotating the wheel from you.

Abstraction:

Before mentioning anything about abstraction, we can take three different users here (I am calling them as entity)

1) You 2) Local Mechanic 3) Expert

You Entity: Since you know only to start the car by pressing a button and all other operations behind the scene are abstracted from you.

Local Mechanic Entity: Our local mechanic knows some of the implementation of starting the car, i.e. he can open car's bonnet and check the battery cable or chock etc. So in short Local Mechanic Entity knows some of the implementations of the car.

Expert Entity: Since our expert (Designer of the car) mechanic knows all the operations of our car, he can repair it very quickly. So in short Expert Entity knows all the implementations of the car.

The car's operation is completely abstracted from you and it is partially implemented to Local Mechanic Entity and fully implemented to Expert Entity. So you are an abstract class having only abstract methods, Local Mechanic Entity has extended You(Since he is also an ordinary user) and he implemented some of the methods and last our expert Entity extending Local Mechanic and implementing all the methods.

I think this is a good example.

Answer 3

Let me give my 2 cents of a real-world example-analogy close to IT.

Lets say you have a subscription site, e.g a wordpress site

Each user has a role, eg admin, subscriber and so on. Many users can be admins, subscribers etc..

So abstraction here is reflected in the fact that any user with admin role can do a set of things, it does not matter which specific user this is (this is an example of abstraction).

On the other hand, subscriber users do not have access to certain settings of the site, thus some internals of the application are encapsulated for plain subscribers (this is an example of encapsulation)

As one can see abstraction and encapsulation are relative concepts, they apply with respect to something specific.

One can follow this line of reasoning and explain polymoprhism and inheritance.

For example super-admin users could do all the things admin users could do, plus some more. Moreover, if admin roles get an update in functionality, super-admins would get the same update. Thus one can see here an example of inheritance, in that super-admin roles inherit all the properties of admin roles and extend them. Note that for most part of the site, admins are interchangeable with super-admins (meaning a super-admin user can easily be used in place of an admin user, but not vice-versa in general).

Answer 4

Encapsulation helps in adhering to Single Responsibility principle and Abstraction helps in adhering to Code to Interface and not to implement.

Say I have a class for Car : Service Provider Class and Driver Class : Service Consumer Class.

For Abstraction : we define abstract Class for CAR and define all the abstract methods in it , which are function available in the car like : changeGear(), applyBrake().

Now the actual Car (Concrete Class i.e. like Mercedes , BMW will implement these methods in their own way and abstract the execution and end user will still apply break and change gear for particular concrete car instance and polymorphically the execution will happen as defined in concrete class.

For Encapsulation : Now say Mercedes come up with new feature/technology: Anti Skid Braking, while implementing the applyBrake(), it will encapsulate this feature in applyBrake() method and thus providing cohesion, and service consumer will still access by same method applyBrake() of the car object. Thus Encapsulation lets further in same concrete class implementation.

Answer 5

Encapsulation is hiding information.

Abstraction is hiding the functionality details.

Encapsulation is performed by constructing the class. Abstraction is achieved by creating either Abstract Classes or Interfaces on top of your class.

In the example given in the question, we are using the class for its functionality and we don't care about how the device achieves that. So we can say the details of the phone are "abstracted" from us.

Encapsulation is hiding WHAT THE PHONE USES to achieve whatever it does; Abstraction is hiding HOW IT DOES it.-

Answer 6

Abstraction : you'll never buy a "device", but always buy something more specific : iPhone, GSII, Nokia 3310... Here, iPhone, GSII and N3310 are concrete things, device is abstract.

Encapsulation : you've got several devices, all of them have got a USB port. You don't know what kind of printed circuit there's back, you just have to know you'll be able to plug a USB cable into it.

Abstraction is a concept, which is allowed by encapsulation. My example wasn't the best one (there's no real link between the two blocks).

You can do encapsulation without using abstraction, but if you wanna use some abstraction in your projects, you'll need encapsulation.