java - Determine the super class reference used to call method in subclass -


i've been asked couple of times, & stumped on how , why 1 go it.

here's scenario:

interface inta {     void somemethod(); } interface intb {     void somemethod(); }

two simple interfaces; implemented below in simple class

class classab implements inta,intb {     @override     public void somemethod(){         //some logic     } }

then instantiate & use so:

inta = new classab(); a.somemethod();

or through other interface:

intb b = new classab(); b.somemethod();

now question in implementation of somemethod(), can find out if used inta reference or intb reference invoke somemethod(). , accordingly, execute different logic.

i feel wrong question. don't understand why & how 1 that. interfaces point of view, has implementation meets criteria of function signature & that's matters. if inta & intb expect different results, ought implemented in 2 different classes.

i've come across scenario twice, hence why i'm asking. there way determine? there way in other languages c/c++?

not can't (except complicated wizardry), you've said, there's no reason try it.

the scenario might come up, if you've accidentally given same method signatures 2 interfaces commonly used , may end being implemented in same class together, distinct functionality. that's design error on interfaces' part.

there's no clean way around it, , unclean way complicated nobody in right mind attempt it. correct course of action refactor either 1 of interfaces use different method signature. sign of bigger design problems if scenario has come twice already.


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