Spring AOP Education Masterpiece. The best lecture I'm sorry to the instructor that the maximum number of stars I can give is only 5. Thank you so much for the great lecture. As a side note, if you practice following the instructor's code and then debug the internal implementation logic of SpringObjenesis, CGLIB, and JDK dynamic proxy (ProxyFactory, ObjenesisCglibAopProxy, etc.) separately, you will probably get much more out of it. Personally, I debugged the moment of initialization with ProxyFactory proxyFactory = ProxyFactory(Component without interface); and went through various procedures according to the rules until I saw with my own eyes that it uses objenesis when creating and returning a proxy object as the result value of getProxy(). If I hadn't watched the lecture, I would not have understood anything because I didn't know the outline of the workflow at all. Also, I felt that my understanding of Spring AOP greatly improved while separately looking into the process in which the AspectJAutoProxyRegistrar class related to EnableAspectJAutoProxy gets types annotated with @Aspect and uses BeanPostProcessor in the subsequent logic to register proxy objects as Spring beans instead of actual objects. I am deeply grateful that you showed me the big picture first so that I could understand the detailed operation of the actual logic.