Generics & Optional in Java: interview exercises

Generics & Optional in Java: 6 test-checked interview exercises (A generic pair, A bounded generic method), each beside a worked example, with tests as you go. Free.

1. A generic pair
2. A bounded generic method
3. An Optional chain
4. A stack that knows its minimum
5. Return a Comparator
6. Compose functions

Each exercise pairs a worked example with a twin problem to solve in a real editor; the tests run the moment you do. Interview mode hides the example: solve it from memory, without the hint or the solution, and it counts as solved cold. Progress is saved in your browser, and in your account if you sign in.

More Java topics

• Strings
• Collections
• Streams & lambdas
• Records, classes & interfaces
• Exceptions & validation
• Algorithms & recursion
• Modern Java

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