What is abstraction and difference between interface and abstract class

Question

Accepted Answer

Abstraction is a way of hiding implementation details. An interface is a contract that specifies the behavior of a class.

Abstraction is achieved through abstract classes and interfaces
Abstract classes can have both abstract and non-abstract methods
Interfaces can only have abstract methods and constants
A class can implement multiple interfaces but can only inherit from one abstract class
Abstract classes can have constructors but interfaces cannot
Example: An abstract class 'Animal' with abstract method 'makeSound' and a non-abstract method 'eat'
Example: An interface 'Drawable' with method 'draw' and a constant 'COLOR'

Accepted Answer

Abstraction is nothing but hiding the implementation details or business logic.

In abstraction is two types

1)partial abstraction

2)Fully abstraction

Partial Abstraction

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1)Partial abstraction can be achieved through abstract class

2)In partial abstraction we have two types of methods abstract method and non abstract method.

3)Abstract method : Hiding the business logic

4)Non abstract method : same as normal method

Fully abstraction

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Fully abstraction can be achieved through Interface

We have only abstract method

We cannot create object for this

To access to another class we can use implements keyword.

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