jpa/subsystem/src/main/java/org/jboss/as/jpa/container/SFSBCallStack.java
public static Map<String, ExtendedEntityManager> currentSFSBCallStackInvocation() {
        ArrayList<Map<String, ExtendedEntityManager>> stack = CURRENT.get().invocationStack;
        if ( stack != null && stack.size() > 0) {
            return stack.get(stack.size() - 1);
        }
        return null;
    }
public static Map<String, ExtendedEntityManager> currentSFSBCallStackInvocation() {
        ArrayList<Map<String, ExtendedEntityManager>> stack = CURRENT.get().invocationStack;
        if ( stack != null && stack.size() > 0) {
            return stack.get(stack.size() - 1);
        }
        return null;
    }
return for just the current entity manager invocation

@return