Records, classes & interfaces in Java: interview exercises

Records, classes & interfaces in Java: 6 test-checked interview exercises (A record that validates itself), each beside a worked example, with tests as you go. Free.

1. A record that validates itself
2. An interface with a default method
3. A sealed expression tree
4. An enum with behaviour
5. The builder pattern
6. equals, hashCode and toString

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
• Generics & Optional
• Exceptions & validation
• Algorithms & recursion
• Modern Java

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