Polymorphism Question

output:
super
sub display
Integer
sub


how in the above code the A class constructor gets called ?
the first statment of constructor should be call to this or super,if neither of them are explicitly put the compiler implictly calls super()
so,there should be no call to super as in the above code

mohitkumar gupta wrote:the first statment of constructor should be call to this or super,if neither of them are explicitly put the compiler implictly calls super()

The B() constructor calls B(int). Since that doesn't have a this or super call in it, then as you've just quoted above the compiler implicitly calls super().

A super-class constructor will always be called, one way or another.

mohitkumar gupta wrote:

how in the above code the A class constructor gets called ?
the first statment of constructor should be call to this or super,if neither of them are explicitly put the compiler implictly calls super()
so,there should be no call to super as in the above code

What about int - argument constructor?

BTW, Your topic and question seems to be different? And have look on the disp() method of your sub class~! If both are doing same operation, then you can't identify which one get called!~ Change it, and then check it.

Just read the quote you posted carefully and you should find a solution :-)

By the way, I think you have a mistake in your code. The superclass method disp() should print something like "super display". Then you will see that the constructor of A class is also aware of the polimorphism and will call the B.disp();


Edit: Gosh, Abimaran you were 7 seconds faster :-)

Cheers!

One advise: Don't call the overridden methods within Constructors. But, you can predict which one will be called! Can you?

Pedro Kowalski wrote:
Edit: Gosh, Abimaran you were 7 seconds faster :-)
Cheers!

Not that all!

For compiler this

is equal to this

for better understanding