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The moose likes Programmer Certification (SCJP/OCPJP) and the fly likes Downcasting Big Moose Saloon
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Harikrishna Gorrepati
Ranch Hand

Joined: Sep 23, 2010
Posts: 423

I have given the question in the comments..Please advice.

OCPJP 6.0-81% | Preparing for OCWCD | |
Ankit Garg

Joined: Aug 03, 2008
Posts: 9452

Yes null value is downcasted to type Hyderabad and then automatically upcasted to AP. null value can be type casted to any type which is not a primitive...

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Rahul Saple
Ranch Hand

Joined: Aug 02, 2006
Posts: 46
Yes, we are explictly downcasting the reference (Universe) to Hyderabad and the compiler does the implicit Upcasting (since it is always error free) for us. Assigning a null value is never a problem. Only using(calling a method, accessing a field) a reference pointing to no object in particular(null) leads to an exception. Infact, a non-local reference variable when declared has its default value set to null.
I agree. Here's the link:
subject: Downcasting
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