Difference between abstract class and interface

by admin · Published May 16, 2019 · Updated September 9, 2020

Number	Abstract Class	Interface
1	Abstract class is defined with keyword abstract	Interface is defined with keyword interface
2	Abstract class can be consider as data type	Interface can be consider as data type
3	In abstract class data member can be anything i.e int or float or String etc.	In interface data member is automatically public static and final
4	We can't create a object of Abstract class	We can't create a object of interface
5	Abstract class can have Constructor	Interface can't have Constructor
6	Default access modifier of any method in abstract class is default	Default access modifier of any method in interface is public
7	Abstract class can have method with any access modifier i.e method can be public or private or protected or default etc	Interface has methods with only public access modifier
8	Any class can extend abstract class using keyword extends	Any class can implements interface using keyword implements
9	Abstract class can extend any other class	Interface can't inheritate any class even not object class
10	Multiple inheritance is not possible	Multiple inheritance is possible
11	When you know implementation of few methods then go for abstract class	If you don't know implementation of any method then go for interface
12	Abstract class can have abstract methods ,static methods as well as non-static methods	Interface can have abstract methods as well as static methods but not non static methods