Generic, Policy-Aware CRUD Scaffolding Architecture for Object-Oriented Systems with Template-Based Controller-Service-DAO and Navigable Retrieval

CRUD (Create, Read, Update, Delete) endpoints dominate many enterprise codebases, yet their implementations are frequently repetitive and inconsistent in cross-cutting concerns such as authorization, exception mapping, pagination, navigation, export/import, and batch operations. This paper presents an object-oriented design that factors these concerns into reusable, type-parameterized base components while leaving entity-specific behavior open for extension through well-defined template hooks. A central contribution is a type hierarchy that unifies navigation and CRUD contracts, and a binding model where the base DAO can implement the base service contract (e.g., BaseDAO implements BaseService) while a concrete entity DAO implements the entity service interface (e.g., ProductDAO extends BaseDAO implements ProductService). This reduces per-entity boilerplate, preserves interface-driven controllers, and concentrates variability in overridable persistence and mapping hooks.