Hi, I have to study security in JBoss so I'm reading through this
http://docs.jboss.org/jbossas/jboss4guide/r5/html/ch8.chapter.html
but I find it quite hard and thus reading takes an awful amount of time. Do you know any better material (if possibly exists) with meaning of better readability?

If not, then nevermind, but please help me how to understand those weird diagrams there. I totally don't understand them. There are some squares, sometimes connected with lines, some of them are not connected at all, some of them are with extra border, then there are some operators like * or 1, and in squares there are some icons... What that means?? I've NEVER seen diagrams like this and I saw a lot of different diagram types. Can someone, who understand them, explain me even what kind of diagram are they for starter and then what each symbol means? I've already ask few analytics and even them did not know the answer. I've got some ideas what some parts of diagrams could depict, but that's not enough.

thanks in advance
alfonz.