Mastering Java: The Ultimate Quiz for 'Thinking in Java'

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Mastering Java: The Ultimate Quiz for 'Thinking in Java'. Dive deep into Java with multiple-choice questions. Challenge yourself with quiz questions designed to test and improve your understanding of the 'Thinking in Java' book. Get ready for your exam!

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How do you assign a List<Apple> to a List<? super Apple> variable?

Using direct assignment without any casts
By casting List<Apple> to List<? super Apple>
Using generic wildcard as method parameter
It's not possible to assign List<Apple> to List<? super Apple>

The correct answer is: Using generic wildcard as method parameter

The question is asking how to assign a List of type Apple to a List that can contain either Apple or one of its superclasses (i.e. a List of type Fruit, for example). Option A and D are incorrect because direct assignment and casting are not involved here. Option B is incorrect because you do not need to cast the List of Apple to assign it to a List of wildcard type. Option C is the correct answer because using a generic wildcard as a method parameter allows us to specify that the List can contain either an Apple or one of its superclasses. This makes it possible to assign a List of Apple objects to a List of any supertype of Apple.