On Wed, Oct 3, 2018 at 7:53 PM Sergey Bylokhov <sergey.bylok...@oracle.com> wrote: > Hi, Sean. > One question related to SecurityManager and performance, is it possible > to provide a special version of AccessController.doPrivileged which will > be noop if SecurityManager is not present?
TBH that method (at least, the no-arg variant) should *always* have been a no-op. All it really accomplishes, in practice, is to place a mark on the stack where the stack crawl to build the access control context should stop (plus one frame), and this effect is something that is already a natural consequence of a method being called in the JVM. The doPrivileged variant that accepts an ACC parameter should likewise always have been no-op other than stashing the nested ACC into some sort of thread-local (or better, a field on Thread) which can be referred to by the aforementioned stack crawl. The pure-java AccessController I prototyped late last year relies on these ideas, among other things. -- - DML
