Abstract class vs interface

Question

Accepted Answer

Abstract class is a class that cannot be instantiated, while an interface is a contract that a class must implement.

Abstract classes can have implemented methods, while interfaces cannot
A class can implement multiple interfaces, but can only inherit from one abstract class
Interfaces are used for achieving multiple inheritance in Java
Abstract classes are used for creating a base class for other classes to inherit from
Example of abstract class: public abstract class Animal { public abstract void makeSound(); }
Example of interface: public interface Flyable { void fly(); }

Accepted Answer

An abstract class is used as a base class from which other classes can inherit, it cannot be instantiated on its own and it uses the "extends" keyword while an interface is a contract that defines a set of method signature that a class must implement and it uses implements keyword.

Abstract class vs interface

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