Vimlesh Kumar

 Profile Answers by Vimlesh Kumar 

• Sep 15th, 2011

 

When you have some methods to be implemented as common and some methods you want to keep abstract, that time we will go for abstract class. You want to provide contract between class and object. And you don't want to implement any method as common that time we will go for interface.

Shivang Modi

• Oct 5th, 2011

 

Whenever there is need of having same common features among all subclasses of super class, we have to go for an abstract class.
Whenever there is no common features for subclasses of super class, we have to go for an interface.

AFROZ AZAM

• Oct 23rd, 2011

 

When we want to implement a class in future we go for abstract class.

we go for interface in order to achieve 100% abstractness.

Fathima

• Dec 16th, 2011

 

When the sub-types behaviour is totally different then you use an interface, when the sub-types behaviour is partially common and different with respect to the supertype an abstract class is used.

ankit_maangat

 Profile Answers by ankit_maangat 

• Dec 20th, 2011

 

When you want to extend more than one then go for interface because java does not support multiple inheritance. So you can not extends more one class but using interface we can do it.

sampra

 Profile Answers by sampra 

• Mar 6th, 2012

 

Correct ans would be:Whenever there is need of having same common features among all subclasses of super class, we have to go for an abstract class.
Whenever there is no common features for subclasses of super class, we have to go for an interface.

Praveen Kumar Singh

• Mar 13th, 2012

 

When you have some methods to be implemented as common and some methods you want to keep abstract, that time we will go for abstract class. You want to provide contract between class and object. And you don't want to implement any method as common that time we will go for interface.