Difference between Abstract class and inteface

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Accepted Answer

Abstract class is a class that cannot be instantiated and can have both abstract and non-abstract methods. Interface is a collection of abstract methods.

Abstract class can have constructors while interface cannot
A class can implement multiple interfaces but can only inherit from one abstract class
Abstract class can have instance variables while interface cannot
Abstract class is used when we want to provide a common base implementation to derived classes while interface is used when we want to provide a common behavior to unrelated classes
Example of abstract class: Animal class with abstract method 'makeSound'
Example of interface: Comparable interface with abstract method 'compareTo'

Difference between Abstract class and inteface

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