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Question on "instanceof"

 
Greenhorn
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Why the code's output is :
ture
true
true
true


:roll: :roll:
 
author and iconoclast
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46
Mac OS X Eclipse IDE Chrome
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The type of the variable "i" doesn't matter at all. All that matters is the type of the object it points to, which is class B. Just remember that "instanceof" is evaluated at runtime.

An instance of B is an instance of A because B extends A.

A B is a B, of course.

A B is an I1 because A implements I1, and B extends A.

And a B is an I2 because B implements I2.
 
Ernest Friedman-Hill
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The type of the variable "i" doesn't matter at all. All that matters is the type of the object it points to, which is class B. Just remember that "instanceof" is evaluated at runtime.

An instance of B is an instance of A because B extends A.

A B is a B, of course.

A B is an I1 because A implements I1, and B extends A.

And a B is an I2 because B implements I2.
 
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