What are the key AOP terms: Aspect, Join Point, Pointcut, and Advice?

AOP (Aspect-Oriented Programming)

An Aspect is the module containing the cross-cutting logic (a class annotated @Aspect). A Join Point is a specific point during execution where an aspect could apply — in Spring AOP, always a method call. A Pointcut is an expression that selects which join points a given piece of advice applies to (e.g., 'all methods in the service package'). Advice is the actual action taken at a matched join point (the code that runs before/after/around it).