Saturday 27 September 2014

Session 15:-Interface


What is Interface ? 

  •   Interface is medium between two different system, when in implementation in the other  system and we use interface to access the implementation 
  •   Interface can’t have concrete method that it is inside the interface all abstract 
  •   When a class inherit an interface by using keyword  implement that class child    mediatory override all the method implement which define in interface if not than child class is abstract class 
  •   We can’t create object of interface rather an interface can refers any object of child object in the entire inheritance hierarchy. 
  •   The method inside an interface is implicitly public. 
  •   The methods an interface all are only public. 
  •   The variable inside the interface are implicitly public, static, and final. 
  •   Interface can also be treated or consider as rules repository. 
  •   Interface can use generally when we deal with third party.
  •   Interface can’t have constructor. There is no need of initialization of state or behavior.
  • Interface can inheritance number of inheritance by using the extend. 
  •        A class can inherit one class (parent) and any N number of interfaces at a same time.
     

Advantage

  •   Multiple inheritances possible. 
  •   Loose coupling. 
  •   Zero dependencies. 
  •   Can achieve abstraction. 
  •   Standardize way of accessing the implementation. 
  •   Interface can never be the child of any class (not even object class).
Remember following Table:-



Difference between Abstract Class / Interface:-



Think:-“Find out Inbuilt Interface name which are present in java Api??”