I've tried a couple of AspectJ examples recently and I liked what they allowed me to do. Then I tried to instrument some java swing and java core classes (I was just curious how stuff works from inside) and I failed to do that. Is this forbidden on purpose (e.g. security reasons) or there is a workaround... What if I really need to do something like that, is it possible?
Before that I encountered some misleading pages, mentioning dynamic weaving, security, etc., and because I am relatively new to the subject I falsely assumed that this is related to security. Since I wasn't sure that I understand things correctly I've decided to check that by posting question here. This proved as a good decision at the end (I found the answer)