public static boolean isPotentialFutureLocalUser(final JID user) {
        return ALLOW_FUTURE_USERS.getValue() && XMPPServer.getInstance().isLocal(user) && !SessionManager.getInstance().isAnonymousClientSession(user);
    }
Checks if the provided address belongs to a locally registered user that potentially has not registered yet.

This method is intended to be used in use-cases where data addressed at a local user is processed, prior to that
user having received a representation in the user manager. This can occur when users are created on ad-hoc basis,
such as through the result of external authentication.

When the feature that allows future users to be considered is disabled, this method will always return false.

@param user The address of a user
@return True if the address could be used for a locally registered user, potentially not having registered yet.
xmppserver/src/main/java/org/jivesoftware/openfire/user/UserManager.java