Object-oriented programming · interview question
What prints here? Product item = new DigitalProduct(); System.out.println(item.label());?
Multiple choiceMediumchapter-5-curatedpremiumoopmethod-overriding
Answer and explanation
Correct answer
B. The DigitalProduct label, because dynamic dispatch uses the runtime object type
Why
For overridden instance methods, Java uses the runtime object type, not the reference type, to pick the implementation. That is the core of dynamic dispatch and runtime polymorphism.
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