I've seen a lot of posts saying that Instructor Baek Gi-seon's class doesn't suit some people, but it really suited me. It was really easy to listen to the additional explanations on top of the materials he prepared in advance, and I really liked the examples in the source code. He occasionally threw in some swear words, but I thought it was good advice, so I just listened to it and moved on. I only studied versions before Java 8, so it was very helpful. I recommend it to those who want a clean lecture.