Скачать или смотреть Abstraction in java with real time example

This video explanation for abstraction in java.
Abstraction means hiding internal operation implementation details from the user and provide only necessary details to access the object operation is called Abstraction..
ex:--
ATM machine, keyboard, Call button,

How can we develop abstraction class??

Abstraction provides a contract document between object user and object implementer,,

Q//how can we restrict subclass to override super class?
declaring method as final...

what is super class sub class check the video--   • Basic concept inheritance with real time e...  

Q//How can subclass override super class??
Declaring method as abstract we can override..

Abstraction method??
Those methods having only pro type and doesn't have body called abstract method...


ex: abstract void java;

What is abstract class??
A class that is declared with abstract modifier is called Abstract class...it is partial implementation class...it contains both abstract and concurrent method..

when should use abstract class in project?