what is interface and abstraction

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Interface is a blueprint of a class that defines methods without implementation. Abstraction is a concept where only essential details are shown and irrelevant details are hidden.

Interface in Java is a reference type, similar to a class, that can contain only constants, method signatures, default methods, static methods, and nested types.
Abstraction is achieved in Java using abstract classes and interfaces. Abstract classes can have both abstract and non-abstract methods, while interfaces can only have abstract methods.
Interfaces allow for multiple inheritance in Java, as a class can implement multiple interfaces but can only extend one class.
Abstraction helps in reducing complexity by hiding unnecessary details and showing only the essential features of an object.
Example: An interface 'Shape' may have methods like 'calculateArea()' and 'calculatePerimeter()', while an abstract class 'Animal' may have abstract methods like 'eat()' and 'sleep()'.

what is interface and abstraction

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