WildFly security manager use deprecated API for getting of caller.
Currently only public API to look at the call stack as Class instances, which will not be removed in future, is SecurityManager.getClassContext(), which is inefficient to use in performance critical parts.

Efficient replacement of this API not exist yet, should be added in Java 9:
https://bugs.openjdk.java.net/browse/JDK-8043814

This task can be resolved only after resolving JDK-8043814.

When mentioned enhancement proposial will be implemented, it shoudl replace current SecurityManager.getClassContext() fallback. But this new API only replace current fallback for Java 9 - deprecated API must stay for Java 8.

This issue is related to following build warning: (mentioned for search)

WildFlySecurityManager.java:[117,32] getCallerClass(int) in sun.reflect.Reflection has been deprecated