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). Keep domain logic framework-free. Validate: Assert all invariants are covered by unit tests before advancing.

3. Expose Domain Ports

Declare repository interfaces in domain/repository describing persistence contracts without implementation details. Validate: Confirm interface signatures match domain operations.

4. Provide Infrastructure Adapter

Create JPA entities in infrastructure/persistence that map to domain models. Implement Spring Data repositories. Validate: Run @DataJpaTest to verify entity mapping and repository integration.

5. Implement Application Services

Create @Transactional service classes that orchestrate domain operations and DTO mapping. Validate: Ensure transaction boundaries are correct and optimistic locking is applied where needed.

6. Define DTOs and Controllers

Use Java records for API contracts with jakarta.validation annotations. Map REST endpoints with proper status codes.