Practice Autoboxing And Unboxing (6.5) - Primitive Values, Wrapper Classes, Types, and Casting

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9 questions

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4 cards from this section. Quick, good the night before a test.
Exercise
6 questions · about 4 min · pass mark 70%. Hints available.
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Quiz
3 questions · about 2 min · pass mark 70%. Hints available.
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6 sample questions

Question 1.
What does AutoBoxing do?
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Think about what happens when you assign an int to an Integer.
Question 2.
What is the opposite of AutoBoxing?
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Remember what happens when you retrieve a primitive from its wrapper.
3Question 3.
What is AutoBoxing?
- Converting an object to a primitive
- Converting a primitive to an object
- Neither of these
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Think about the direction of the conversion.
4Question 4.
True or False: UnBoxing can lead to a NullPointerException.
- True
- False
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Consider what happens when trying to access null.
Question 5.
Write a Java program that illustrates both AutoBoxing and UnBoxing processes while storing multiple primitive types in an ArrayList.
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Think about how you store numbers in ArrayLists and return them back as primitives.
Question 6.
Discuss the potential risks of UnBoxing a null value in Java and provide code to demonstrate the issue.
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Think about what happens when you try to retrieve a primitive from a null wrapper.

5 more questions in this section. Enroll free to practise them all.