Question

Which of these methods calls update() method?

(a) notify()

(b) observeObject()

(c) updateObserver()

(d) notifyObserver()

This question was addressed to me in an interview.

I need to ask this question from Observable & Timer Class in portion java.util – More Utility Classes of Java

Answer 1

The correct answer is (d) notifyObserver()

For explanation: notifyObserver() notifies all the observers of the invoking object that it has changed by calling update(). A null is passed as the second argument to update().