Return type

[niku shah]

class plant
{
plant getType() {return this;}
}

class flower extends Plant{ //insert code here}

class tulip extends flower{}

which will compile inserted at //insert code here ?

A. flower getType(){return this;}

B. String getType(){return this;}

C. Plant getType(){return this;}

A. tulip getType(){return new tulip();}

Answer in K&B is A , C and D are true
I am sure about A and C but not sure about tulip...

as per the polimorphism we can return super type of flower i.e plant or flower itself , but how can we sent value of its subclass ?

Thank you

Nikesh

[Sanjeev Singh]

Being a case of covariant return type the overriding method in class Flower can return the objects of Plants and its subtype.

A.this returns the reference to a flower object which in turn is a Plant.
B.Compilation error as flower can not be a String.
C.this(flower) is a Plant,so it is fine to place this methods also.
D.Tulip is a Flower and Flower is a Plant which implies Tulip is a Plant.(check with instanceof)