@Override
    public Set<DataForm> getExtendedInfos(String name, String node, JID senderJID) {
        if (name == null && node != null) {
            // Answer the extended info of a given node
            Node pubNode = getNode(node);
            Set<DataForm> dataForms = new HashSet<>();
            if (canDiscoverNode(pubNode)) {
                final Locale preferredLocale = SessionManager.getInstance().getLocaleForSession(senderJID);
                dataForms.add(pubNode.getMetadataForm(preferredLocale));
                // Get the metadata data form
                return dataForms;
            }
        }
        return new HashSet<>();
    }
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