jackson-kotlin-serialization-specialist

Jackson DTO deserialization fails when jackson-module-kotlin is missing or misconfigured, preventing Kotlin default parameter invocation. The specialist diagnoses constructor semantics, nullability, and module alignment to ensure correct deserialization behavior.

PATCH semantics require distinguishing null from absent fields by carefully handling Kotlin nullability and Jackson deserialization. The specialist designs custom serializers and nullability rules to prevent unintended overwrites and wire-format drift.

Fixing date-time format drift requires aligning JavaTimeModule with your Jackson configuration in Spring. The specialist diagnoses date-time or enum format drifts and prescribes corrections to maintain consistent wire formats.

Handling polymorphic payloads requires careful management of Kotlin type discriminators to avoid breaking API contracts. The specialist designs polymorphic type configurations and custom serializers to ensure correct deserialization.

Jackson works with Kotlin nullability when properly aligned with jackson-module-kotlin, JavaTimeModule, and custom serializers. The specialist diagnoses unknown properties and nullability behavior to prevent contract violations.

Diagnosing unknown property failures involves checking Jackson module configuration and Kotlin DTO constructor semantics. The specialist provides examples and prescriptions for handling unknown properties and preventing deserialization exceptions.