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Why doesn't i==b not give a compilation error?
 
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Hi Swarna,


In the case of interfaces, no error in some cases.
Case 1: Compiler thinks b may have reference to the object of the class that
implements the interface I; so no error;

Case 2: a==c fails because IS-A test fails.

Case 3: i==sb gives error because StringBuffer is a final class and compiler knows that case 1 can never be true. (final class can never be extended, so there is no question that subclass of sb could refer to object of the class that implements interface i)

Pay attention to what I said until final.

Regards,
 
swarna dasa
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Thanks.. missed on StringBuffer being a final class.
 
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excellent question and very good response.

Thanks,

Abdul Mohsin
 
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excellent question and a superb reply.


cheers
 
Abdul Mohsin
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Hi swarna,

Can you tell me from where you got that question?

Regards,

Abdul Mohsin
 
swarna dasa
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Oops - Forgot to mention the source - Me
 
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Good question.
superb reply.and really worthable question and reply
 
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