Answer Posted / jyotsna gupta

Abstract Class | Interfaces
|
1. Starts with a class keyword | Starts with interface
| keyword
2. abstract modifier has to be | No need to provide abstract
provided | modifier (100 % Abstract)
3. Not necessary to contain | All methods are by default
abstract methods, but if a | public and abstract, and
class has abstract method | all attributes are public
then class has 2 be abstract| static, and final (FIELDS)

4. Used for group of related | Any class can implement
classes only | interfaces

5. Single inheritance is | Multiple inheritance can
allowed only | be achieved

6. All class behaviours are | Cannot have constructors,
allowed, except creating | should initialise its
objects of abstract classes | Fields

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