Stabilize record validation boundary
Medium Java arena: records, constructors, immutability, and validation
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Missing prerequisites: java-easy-record-validation
A payment command object must reject invalid amounts before reaching business logic. You are working inside a Java backend interview lab, and the arena only clears when the result is safe, deterministic, and explainable.
Learn to apply records, constructors, immutability, and validation in a Java backend interview lab while explaining the invariant, safety constraints, and hidden edge cases.
- Demonstrates records, constructors, immutability, and validation
- Handles the visible sample and hidden edge cases
- Keeps output deterministic and explainable
- Avoids unsafe dynamic execution
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