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What is covariant type

 
Ranch Hand
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HI Ranchers,

K&B pg 111 says,"In Overriding return type can’t change except for
covariant returns."

What does it mean exactly?

Regards,
Nancy
 
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Did you do a simple google search??
 
Bartender
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Here is a more fancy URL

http://lmgtfy.com/?q=what+is+a+covariant+return
 
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Covariant type means your return type of the overriding method should be subclass of the return type of overridden method.

 
Ankit Garg
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Deepak Bala wrote:Here is a more fancy URL

http://lmgtfy.com/?q=what+is+a+covariant+return



 
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Ankitt Gupta wrote:Covariant type means your return type of the overriding method should be subclass of the return type of overridden method



I would say Ankitt it may be a subclass be not that it should be.
 
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Or it could be an implementing class, or an extending interface, if the return type of the overridden method is an interface. The key is that the covariant return must pass the Is-A test for the return type of the overridden method.
 
Nancy Antony
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Thanks Ranchers
 
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