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Abstract Class vs Interface


Interface
Abstract
Declare With keyword “Interface”
Declare with keyword “Abstract”
A class may inherit several interfaces.
A class may inherit only one abstract class.
An interface cannot provide any code, just the signature.
An abstract class can provide complete, default code and/or just the details that have to be overridden.
No fields can be defined in interfaces
An abstract class can have fields and constrants defined
An interface cannot have access modifiers for the subs, functions, properties etc everything is assumed as public
An abstract class can contain access modifiers for the subs, functions, properties
 
It can come in inheritance chain
 
In that this is not come in inheritance chain
Slower
 
Faster
It will not contain constructor
 
It will may or may not constructor
It will only contain final variable
 
It will contain Final and instance variable

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Comments

  1. Babu KumararasamyApril 19, 2016 at 6:00 AM

    The modifier 'abstract' is not valid on fields. Try using a property instead.

    ReplyDelete

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