This time, I think I can do well even if I introduce AOP. Every time I tried to introduce Spring AOP, I always felt like something wasn't working out the way I wanted, so I couldn't introduce it... I guess I didn't know how to use it. Haha After taking this lecture and learning the basic principles of Spring AOP, I gained confidence that I can use AOP. Also, the ThreadLocal and design patterns that you taught before learning Spring AOP in earnest were really helpful to me personally. I hope I can have a chance to use them in my work soon. Lastly, I personally really liked what you said in the last lecture. Thank you!