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. 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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