spring-boot-crud-patterns

# Spring Boot CRUD Patterns ## Overview Provides complete CRUD workflows for Spring Boot 3.5+ services using feature-focused architecture. Creates and validates domain aggregates, JPA repositories, application services, and REST controllers with proper separation of concerns. Defer detailed code listings to reference files for progressive disclosure. ## When to Use - Create REST endpoints for create/read/update/delete workflows backed by Spring Data JPA. - Implement feature packages following DDD-inspired architecture with aggregates, repositories, and application services. - Define DTO records, request validation, and controller mappings for external clients. - Diagnose CRUD regressions, repository contracts, or transaction boundaries in existing Spring Boot services. - Trigger phrases: **"implement Spring CRUD controller"**, **"create an endpoint"**, **"add database entity"**, **"refine feature-based repository"**, **"map DTOs for JPA aggregate"**, **"add pagination to REST list endpoint"**. ## Instructions Follow this streamlined workflow to deliver feature-aligned CRUD services with explicit validation gates: ### 1. Establish Feature Structure Create `feature/<name>/` directories with `domain`, `application`, `presentation`, and `infrastructure` subpackages. **Validate**: Verify directory structure matches the feature boundary before proceeding. ### 2. Define Domain Model Create entity classes with invariants enforced through factory methods (`create`, `update`). ...