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Q) What about abstract class? Explain?




A)
->if we apply “abstract” modifier to concrete class, it becomes an abstract class.
Ex:
class A
{

}   //concrete class(non-abstract class)

abstract class A
{

}   // abstract class

->abstract class is similar to a concrete class in all aspects, Except 2 differences.
1) It can abstract methods
2) It can’t be instantiated.

->similarity between normal class and abstract class
      Both are user defined classes.
      Both normal and abstract classes are contain the fallowing
-class variables and instance variables
-constructors
-static methods
-instance methods
->to prevent object creation only the abstract class is declared.
->the most generalized class is declared as “abstract class”. i.e. the more generalized class means the top most class in the hierarchy is called most generalized class.

2 important thinks of abstract method:-
1)      70% to 80% token to creating prototype then the implementation of behavior taken 20%.
2)      Enforcing the method overriding.

->abstract class object is not created but reference can be created.

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