Difference between abstract class and interface

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

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