Return a Comparator in Java

Java interview exercise on Generics & Optional, difficulty 2 of 3. Solve it in the editor beside a worked example, or cold in Interview mode with the example hidden; the tests run the moment you do.

Given record Employee(String name, String dept, int salary), write byDeptThenSalary() that returns a Comparator<Employee> ordering by department ascending, then salary descending, then name ascending. Build it from Comparator.comparing, thenComparing and reversed order.

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.

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