Spring Boot Project Structure: Best Practices Used in Production🚀

I got lucky early in my career - I was handed a well-structured project to work on, and without even realizing it, I was absorbing good patterns just by reading the code. A few things clicked immediately, but honestly, most of it made sense only over time, as I started new projects from scratch and felt the pain of getting it wrong. This article is what I wish I'd had before that first greenfield project. Table of Contents Why Project Structure Matters The Layered Architecture Recommended Package Structure 1. Controller — Keep It Thin 2. Service — Interface + Implementation Pattern 3. Repository — CrudRepository vs JpaRepository 4. Entity — Map to Database Tables 5. DTOs — Don't Expose Your Entities 6. Custom API Response Wrapper 7. Global Exception Handling Bonus: Feature-Based Structure → The Path to Microservices The resources Directory Summary Why Project Structure Matters A well-organized project: Makes the codebase readable for new team members Separates concerns so each layer ha