15.10.1 - Unbounded Wildcards
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Practice Questions
Test your understanding with targeted questions
What is the symbol for an unbounded wildcard in Java?
💡 Hint: Think of a placeholder for any type.
Which operation is not allowed with unbounded wildcards?
💡 Hint: Remember, since the type is unknown, you cannot add.
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Interactive Quizzes
Quick quizzes to reinforce your learning
What does <?> represent in Java?
💡 Hint: Think of it as a placeholder.
Can you add elements to a collection of type List<?>?
💡 Hint: Consider what you can and cannot do with unknown types.
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Challenge Problems
Push your limits with advanced challenges
Write a Java method that accepts a List<?> and counts the number of elements. Provide your reasoning.
💡 Hint: Think about iterating through the list.
Propose a scenario in application development where unbounded wildcards are particularly useful, explaining your reasoning.
💡 Hint: Consider how libraries handle various data types.
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