This week's book giveaway is in the OCP forum. We're giving away four copies of OCP Java SE 8 Programmer II Exam Study Guide and have Kathy Sierra, Bert Bates, & Elizabeth Robson on-line! See this thread for details.
The book says that Using reflection API shold be avoided to ensure bean portability across all EJB 2.0 containers.
I think the question is not clear, and strictly speaking it is wrong. Reading the spec I understand that you should not use reflection API in case you want to access information that the security rules of Java language make unavailable (see pg. 495).
But if I have a value bean, who's attributes are changing quite ofent, I see no reason why should't I use reflection to get it's public accessor methods.