Object-oriented programming · interview question
What does upcasting a PremiumCustomerDiscountPolicy to DiscountPolicy actually change?
Multiple choiceHardchapter-5-curatedpremiumoopupcasting-and-dynamic-dispatch
Answer and explanation
Correct answer
D. The caller sees only the DiscountPolicy contract, but the runtime object still decides overridden behavior
Why
Upcasting changes what the caller is allowed to see through the reference. It does not erase the runtime type, so overridden instance methods still come from the real implementation object.
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