How interface is different from abstract classes?

Question

Accepted Answer

Interfaces are used to define contracts for classes to implement, while abstract classes can provide partial implementation.

Interfaces can only have abstract methods and cannot have any implementation, while abstract classes can have both abstract and concrete methods.
A class can implement multiple interfaces but can only inherit from one abstract class.
Interfaces are used to achieve multiple inheritance in Java, while abstract classes are used to provide a common base for subclasses.
An example of an interface is Comparable, where classes implementing it must define a compareTo method. An example of an abstract class is Shape, which can have abstract methods like calculateArea and concrete methods like getColor.

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