Seonglae ChoCommon functionality that appears repeatedly "across" multiple modules and layers of a program. Not directly related to business logic, but needed almost everywhere
Solutions
AOP (Aspect-Oriented Programming)
A common solution for cross-cutting concerns
Concept: Extract common functionality into "Aspects" and automatically inject them
Example:
→ Applied automatically without writing code directly
Commonly used in Spring, AspectJ, etc.
Middleware / Interceptor
Most common in web development
Examples: Express / FastAPI / Spring
Example (FastAPI):
Decorator / Wrapper
Commonly used in Python
Framework-Level Handling
Most modern frameworks provide built-in solutions:
- Spring Security
- Django Middleware
- NestJS Guard
- FastAPI Dependency