what is difference between Interface and abstract class

Answer Posted / surender kannuri

interface is a specification of method prototype.

all methods in interface are abstract and final.

interface methods are public since they should be available
to third party vendor to provide implementation.they are
abstract because their implementation is left for third
party vendors.


interface contains 0 or more abstract methods.

all methods of interface should implemented in implemented
class.if any method is not implemented then implementation
class should be declared as abstract.

we can't create object to interface.but we can create
reference to interface type.

an interface contains variables ,such as public.static and
final variables.this means all variables of interface are
constant.

an interface cannot implements another interface.
an interface can extend another interface.

it is possible to write a class within an interface.
a class can implements(not extend) multiple interfaces.


abstract class contains 0 or more abstract methods.
all methods of abstract class should be implemented in
subclasses only.
all methods of abstract class should be declared by using
abstract keyword.
we can't create an object to abstract class.

Is This Answer Correct ?    1 Yes 1 No



Post New Answer       View All Answers


Please Help Members By Posting Answers For Below Questions

How do singleton patterns work?

519


Does java have extension methods?

531


What is void keyword?

677


Define array. Tell me about 2-D array.

589


What does int argc char * argv [] mean?

518






What is the super void?

461


What occurs when an object is constructed?

572


What is singleton class in java and how can we make a class singleton?

575


What is the abstract class?

597


What is queue in java?

554


Explain the features of java?

597


List out five keywords related to exception handling ?

601


What is a subsequence of a string?

549


What is stack class in java?

547


Is string serializable in java?

545