Same chapter3 marksDifficulty: Medium
What is dynamic method dispatch, and why is it useful?
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3 marksDifficulty: Medium
What is an abstract class, and how does it differ from an interface in Java?
Original Khojo Papers practice question — not from a past board paper.
Answer
An abstract class is one that cannot be instantiated and may contain both abstract methods, which have no body, and concrete methods with implementations. An interface traditionally contains only abstract methods and constants and defines a contract; a class may extend only one class but implement any number of interfaces.
No citable source has been recorded for this record. Treat it as practice material, not as fact.
Explanation
Interfaces are how Java achieves the effect of multiple inheritance.
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