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Practice Questions
Test your understanding with targeted questions related to the topic.
Question 1
Easy
What does <?> represent in generics?
💡 Hint: Think about flexibility in type.
Question 2
Easy
In the context of wildcards, what does 'extends' signify?
💡 Hint: Consider when reading types.
Practice 4 more questions and get performance evaluation
Interactive Quizzes
Engage in quick quizzes to reinforce what you've learned and check your comprehension.
Question 1
What wildcard allows any type?
- <?>
- <? extends T>
- <? super T>
💡 Hint: Think about 'flexibility'.
Question 2
True or False: The syntax <? extends Number> allows reading elements that are of type Number or its subtypes.
- True
- False
💡 Hint: Think about types of numbers.
Solve 2 more questions and get performance evaluation
Challenge Problems
Push your limits with challenges.
Question 1
Write a method that accepts a list of any type using an unbounded wildcard and calculates the total number of items added to the list. How would you approach it?
💡 Hint: Focus on the size of the list.
Question 2
Create a utility function that adds items of type T to a list that accepts upper bounded wildcards. Provide an example of its usage.
💡 Hint: Think of the method signature and its parameters carefully.
Challenge and get performance evaluation