@Override
    public void removeNode(Node.UniqueIdentifier nodeID) {
        nodes.remove(nodeID);
    }
Returns true if the service is available. Use {@link #setServiceEnabled(boolean)} to
enable or disable the service.

@return true if the MUC service is available.
xmppserver/src/main/java/org/jivesoftware/openfire/pubsub/PubSubModule.java