What are the differences between an abstract class and an interface in OOPs?

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Accepted Answer

Interfaces define contracts for classes, while abstract classes provide a base with shared code and can have state.

An interface can only declare methods (no implementation), while an abstract class can have both abstract and concrete methods.
A class can implement multiple interfaces but can inherit from only one abstract class.
Interfaces are used for defining capabilities (e.g., Comparable), while abstract classes are used for shared behavior (e.g., base class for shapes).
Example of an interface: 'public interface Drawable { void draw(); }'
Example of an abstract class: 'public abstract class Animal { abstract void sound(); }'

Accepted Answer

1) Abstract class is a class which contains both abstract and non abstract methods. While interface is pure abstract class i.e it only contains abstract methods.
2) Abstract class is a template which should be followed by sub class which is overridden the abstract method. Interface is like a contract which need to be followed by the class which is implementing it.

Accepted Answer

From an object oriented programming perspective, the main difference between an interface and an abstract class is that an interface cannot have state, whereas the abstract class can have state with instance variables.

Accepted Answer

The one major diffrence between both class are abstract has all the modifiers like public private static but interface is only public and we can't use other access modifiers

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What are the differences between an abstract class and an interface in OOPs?

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