What is difference between Interface and abstract class?

Question

Accepted Answer

Interface is a contract that defines the methods a class must implement, while abstract class can have both abstract and concrete methods.

Interface cannot have any implementation, while abstract class 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.
Interfaces are implicitly abstract and public, while abstract classes can have different access modifiers.
Example: Interface - Comparable, Abstract class - Animal with abstract method 'eat' and concrete method 'sleep'.

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