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I feel it difficult to understand the things;
Is this something talking about what reference variable can be passed to the method?

Please help.


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Thanks,
[ May 01, 2007: Message edited by: Chandra Bhatt ]
 
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A and B are fine for obvious reasons
C causes compiler error
D is fine given that all we do is assign it to the lastEvent.
However if one would try to use it, you would get a NullPointerException.

Given the code:- D should be fine as lastEvent is not used.
 
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The point of this question is that if a method expects a reference parameter of type A, then you can send any reference parameter which has the "is a" relationship with A.

One thing this means is that you cannot send a superclass of type A to the method.
 
swarna dasa
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Man!!! you edit your posts in fraction of a second... thats fast..

Yup it deals with inheritance, the kind of reference variables used.

So Reference of the Base class or subclasses would be fine.
 
Chandra Bhatt
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Thanks Swarna and Keith for your prompt reply.
It helped me to get the question correctly.



Thanks,
 
Maybe he went home and went to bed. And took this tiny ad with him:
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