Answer Detail: RE: When to use Interface over abstract class?

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Question: When to use Interface over abstract class?

Answer: Abstract Classes: Classes which cannot be instantiated. This means one
cannot make a object of this class or in other way cannot create
object by saying ClassAbs abs = new ClassAbs(); where ClassAbs is
abstract class.

Abstarct classes contains have one or more abstarct methods, ie method
body only no implementation.

Interfaces: These are same as abstract classes only difference is we
an only define method defination and no implementation.

When to use wot depends on various reasons. One being design choice.

One reason for using abstarct classes is we can code common
functionality and force our developer to use it. I can have a complete
class but I can still mark the class as abstract.
Developing by interface helps in object based communication.

December 12, 2005 09:13:18	#1
g.soma shekar	Member Since: Visitor Total Comments: N/A
RE: When to use Interface over abstract class?
abstract classes are designed with implemantion gaps for sub-class to fill in. interfaces are sintacticlly similar to classes but they lack insance variables & methods. abstract classes can also have both abstract methods & non-abstract methods. where as in interface methods are abstract only, & variables are implicitly static&final.

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