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Covariant returns

C Kushtawar
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Joined: Jan 20, 2009
Posts: 37
This is a simple program that I have written:



But the same program compiles fine when the return types are of Object types as below :




Why is it so?Please explain.
Vierda Mila
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Joined: Feb 25, 2008
Posts: 61
Kusthawar, the explanation is simple Cat is-a Animal so the covariant returns ok, but int is-a NOT long.
Hope it clear your doubt.


SCJP 5
Ravikanth kolli
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Joined: Feb 10, 2008
Posts: 179

As vierda was talking about covariant returns, the return type of a method in subclass should be subclass of the return type of the method in the super class. Animal is a super class of cat so it works fine, but int is not a super class of long.


-kolli
 
I agree. Here's the link: http://aspose.com/file-tools
 
subject: Covariant returns