15.10.3 - Lower Bounded Wildcards
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Practice Questions
Test your understanding with targeted questions
What does the wildcard syntax '<? super T>' allow you to do?
💡 Hint: Think about what the 'super' in the wildcard refers to.
In the context of wildcards, what does PECS stand for?
💡 Hint: It's a mnemonic to help remember how to use wildcards.
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Interactive Quizzes
Quick quizzes to reinforce your learning
What can you add to a List defined as List<? super Integer>?
💡 Hint: Think about what 'super' means in terms of type hierarchies.
In what scenario is it most beneficial to use lower bounded wildcards?
💡 Hint: Consider why you might want more flexibility in what can be added.
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Challenge Problems
Push your limits with advanced challenges
Write a Java method that uses lower bounded wildcards to allow adding elements of different shapes into a list. Describe the potential constraints.
💡 Hint: Think about how shapes can be categorized. You can add circles and squares, but reading needs a specific type.
Imagine a scenario where you need to process different types of vehicles (cars, trucks, etc.). Write a method using lower bounded wildcards to manage these vehicle types.
💡 Hint: Consider what happens when you try to read vehicles from the list. Can you guarantee their type?
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