weather-data/system-common/CLAUDE.md

CLAUDE.md — system-common

Shared Java library used by all backend modules.

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Service layer pattern

Two base classes defined here:

Base	Purpose
CrudService<Dao, Entity, DTO>	Generic CRUD: page(), get(), save(), update(), delete()
BaseService<Dao>	Lighter base without DTO generic

These are used by all service implementations in system-admin and other modules. See system-admin/CLAUDE.md for the full module convention.

i18n validation messages

Located at src/main/resources/i18n/validation.properties. Hibernate Validator messages used by @RestControllerAdvice exception handler in system-admin. Error codes follow int scheme: 5 digits, first 2 = module, last 3 = business (e.g. 10001-10029).