Interface in Java - Complete Explanation in-depth
You can learn Java with me as the Java Programming language is being made easily. It would take a period of minimum three months and maximum 6 months to master Java. I would recommend you to watch all my videos to crack any software interviews that would require Java Programming language as a primary skill.
Interfaces in Java:-
=====================
Interface in a java is used to achieve 100% abstraction.
Points to remember:-
==================
--An interface in java can have only abstract methods.
-- All the methods placed inside the interface are public and abstract by default.
-- You can't instantiate a java interface.(You cant create an object for the java inteface)
-- You can assign a reference variable for an interfaces.
-- A class can make is-a relationship with an interface by using implements keyword.
-- Once the relationship is made, the class has to provide the implementation for all the abstract methods that are inside the interface
-- You can create the object for the class and assign it to the interface reference variables
-- Please be informed that all the variables that is getting defined in an interface is public static final by default.
-- You can't have constructors inside an interface because all the variables are public static final by default.
-- You can't have static methods or final methods inside the interface.
=========================================================================