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Need explain instanceof operator issue

 
Greenhorn
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Hi,
I do not understand why instanceof operator is working as it is working. For example:


cause compilation error - this is clear, there is no IS-A relationship, Dog never ever could be a Cat.
But another example behaviour is weird for me:


works fine. It compiles and also run (and produce false of cource).
So tell me, in which universe Robot could be an Animal?
Why this don't cause compile error?

 
Marshal
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There could be a subclass of Robot which implements Animal. The compiler sees a variable of type Robot; this could be a reference to an instance of that subclass.

Try declaring the Robot class as "final" and see what changes.
 
matej spac
Greenhorn
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wow, so briefly and so clearly :-)
thanks, now I understand
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