Practice Optional Class - 1.7 | 17. Functional Programming in Java | Advance Programming In Java
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Optional Class

1.7 - Optional Class

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Learning

Practice Questions

Test your understanding with targeted questions

Question 1 Easy

What is the purpose of the Optional class in Java?

💡 Hint: Consider how you would check for null values.

Question 2 Easy

How do you create an Optional instance from a potentially null value?

💡 Hint: Remember the method name that indicates possible absence of value.

4 more questions available

Interactive Quizzes

Quick quizzes to reinforce your learning

Question 1

What does the Optional class help prevent in Java?

IndexOutOfBoundsException
NullPointerException
IllegalArgumentException

💡 Hint: Recall the common exception types Java programs face.

Question 2

True or False: Optional can hold null values.

True
False

💡 Hint: Think about what Optional encapsulates.

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Challenge Problems

Push your limits with advanced challenges

Challenge 1 Hard

Write a method using Optional to return an integer value from a collection of numbers, where the number is searched based on criteria (e.g., greater than 10).

💡 Hint: Use streams to filter and find the first matching value.

Challenge 2 Hard

Design an API method that returns a user based on username, using Optional in its return type.

💡 Hint: Consider how the absence of a user will be indicated.

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Reference links

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