public void setRegistrationEnabled(boolean registrationEnabled) {
        this.registrationEnabled = registrationEnabled;
    }
Sets if users are allowed to register with the room. By default, room registration
is enabled. A not_allowed error will be returned if a user tries to register with the room
and this feature is disabled.

@param registrationEnabled if users are allowed to register with the room.
xmppserver/src/main/java/org/jivesoftware/openfire/muc/MUCRoom.java