Difference between Abstract Class & Interface?
- 4 Answers
- 6168 Views
- HCL, IBM, I also Faced
- E-Mail Answers
Answers were Sorted based on User's Feedback
Answer / rakesh.fanu
Abstract Class :-
Abstract class should be declare with abstract.
Abstract Class must be extended by its sub class.
Abstract Class has abstract method and also method with
body also.
Abstract Class has not instance variables , it contain only
Constant.
An abstract class cannot be instantiated
Interface :-
Interface must be Implemented by another class.
Interface has only abstract method.
Interface has not instance variables , it contain only Constant.
An Interface cannot be instantiated
| Is This Answer Correct ? | 6 Yes | 2 No |
Answer / brijendra kumar(xavient)
Abstract Class:
1-Abstact class declare with the abstract keyword.
2-Abstract class contains the both method declaration and
defeination.
3-Abstract class donot have the instant variable.It have
only constrants.
3-Abstract class extended by its sub class.
4-Abstract class support only single inheritence.
Interface:
1-Interface declare with the interface keyword.
2-Interface contains the only collection of method
signature.
3-Interface implement by a class.
4-Interface extended by one or more interfcae.
5-Interface support the multiple inheritence.
6-Interface is useful for java development.
| Is This Answer Correct ? | 1 Yes | 0 No |
Answer / nivas
abstract class is declared in abstract and instance methods
but were as interface class is declared only in abstract method
| Is This Answer Correct ? | 0 Yes | 0 No |
Answer / adikeanand@gmail.com
ABSTRACT CLASS:
1)abstract class contains abstract methods with body and concrete methods also.
2) when a class contains abstract methods declare the class as abstract.
3) when we don't want to allow anybody to create object to the class then declare class as abstract.when we want to use the methods of a abstract class write a class which extends abstract class and create reference variable to abstract class and assign subclass object.
4)We can not create object to the abstract class but we can create reference variable.
INTERFACE:
1)Interface contains abstract methods and static final data.
2)when we are writing a class which implementing interface then we have to provide the body for all the abstract methods of interface.
3)If we don't want to provide all the methods of interface then declare the class as abstract.write the class which extends abstract class and write the methods which you have left abstract methods and create reference variable to interface and assign the object of class which extends abstract class.
| Is This Answer Correct ? | 0 Yes | 0 No |
What is lambda value?
Why dependency injection is used in java?
What is the java virtual machine (jvm)?
Why we use beans in java?
What's the difference between authentication and authorization? : java security
Is eclipse a jdk?
what is the function of OS
I am trying to create a new universal user group. Why can't i? : java security
What is the difference between deep copy and shallow copy in java
what are the steps in JDBC connectivity..???
What is default constructor in java?
What is the means of java?
Java J2EE 
