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what is the difference between

 
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what is the difference between an abstract class and an interface?
 
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Interfaces let you get by the multiple inheritance problem by forcing you to implement all of its methods in a class that implements it. Abstract classes can have defined methods and fields that aren't necessarily public, static, and final.
 
Nikos kat
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thanks for your help
 
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Hi Nikos
Abstract class can have abstract methods as well as concrete methods whereas an interface will have only abstract methods.In one way we can call an interface as a pure abstract class.
We can create constructors for abstract classes whereas that is not possible for an interface.
 
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Hi everyone,
Can we create an instance of any bastract class??

Thanks,

Mert
 
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Nope, it's pretty much the definition of "abstract class" that you can't instantiate one. Somebody has to extend it into a concrete class that you can instantiate. Often an abstract class is "incomplete" ... you see this in methods marked "abstract" that somebody must implement to make a concrete class.
 
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