Collection<MUCRoom> getAll()
    {
        return ROOM_CACHE.values();
    }
Makes available the current state of the provided MUCRoom instance to all nodes in the Openfire cluster (if the
local server is part of such a cluster). This method should be used whenever a MUCRoom instance has been changed.

@param room The room for which to persist state changes across the Openfire cluster.
xmppserver/src/main/java/org/jivesoftware/openfire/muc/spi/LocalMUCRoomManager.java