protected List executeMessageLogic()

in server/extensions/xep0045-muc/src/main/java/org/apache/vysper/xmpp/modules/extension/xep0045_muc/handler/MUCMessageHandler.java [95:219]
85 lines of code
22 McCabe index (conditional complexity)

    protected List<Stanza> executeMessageLogic(MessageStanza stanza, ServerRuntimeContext serverRuntimeContext,
            SessionContext sessionContext, StanzaBroker stanzaBroker) {

        logger.debug("Received message for MUC");
        Entity from = stanza.getFrom();
        Entity roomWithNickJid = stanza.getTo();
        Entity roomJid = roomWithNickJid.getBareJID();

        MessageStanzaType type = stanza.getMessageType();
        if (type == MessageStanzaType.GROUPCHAT) {
            // groupchat, message to a room

            // must not have a nick
            if (roomWithNickJid.getResource() != null) {
                return createMessageErrorStanza(roomJid, from, stanza.getID(), StanzaErrorType.MODIFY,
                        StanzaErrorCondition.BAD_REQUEST, stanza);
            }

            logger.debug("Received groupchat message to {}", roomJid);
            Room room = conference.findRoom(roomJid);
            if (room == null) {
                return createMessageErrorStanza(moduleDomain, from, stanza.getID(), StanzaErrorType.MODIFY,
                        StanzaErrorCondition.ITEM_NOT_FOUND, stanza);
            }

            Occupant sendingOccupant = room.findOccupantByJID(from);

            // sender must be participant in room
            if (sendingOccupant == null) {
                return createMessageErrorStanza(room.getJID(), from, stanza.getID(), StanzaErrorType.MODIFY,
                        StanzaErrorCondition.NOT_ACCEPTABLE, stanza);
            }

            Entity roomAndSendingNick = new EntityImpl(room.getJID(), sendingOccupant.getNick());
            if (!sendingOccupant.hasVoice()) {
                return createMessageErrorStanza(room.getJID(), from, stanza.getID(), StanzaErrorType.MODIFY,
                        StanzaErrorCondition.FORBIDDEN, stanza);
            }

            // relay message to all occupants in room
            try {
                if (stanza.getSubjects() != null && !stanza.getSubjects().isEmpty()) {
                    // subject message
                    if (!room.isRoomType(RoomType.OpenSubject) && !sendingOccupant.isModerator()) {
                        // room only allows moderators to change the subject, and sender is not a
                        // moderator
                        return createMessageErrorStanza(room.getJID(), from, stanza.getID(), StanzaErrorType.AUTH,
                                StanzaErrorCondition.FORBIDDEN, stanza);
                    }
                }
            } catch (XMLSemanticError e) {
                // not a subject message, ignore exception
            }

            logger.debug("Relaying message to all room occupants");
            for (Occupant occupent : room.getOccupants()) {
                logger.debug("Relaying message to  {}", occupent);
                List<Attribute> replaceAttributes = new ArrayList<Attribute>();
                replaceAttributes.add(new Attribute("from", roomAndSendingNick.getFullQualifiedName()));
                replaceAttributes.add(new Attribute("to", occupent.getJid().getFullQualifiedName()));

                relayStanza(occupent.getJid(), StanzaBuilder.createClone(stanza, true, replaceAttributes).build(),
                        stanzaBroker);

            }

            // add to discussion history
            room.getHistory().append(stanza, sendingOccupant);
            room.updateLastActivity();
        } else if (type == null || type == MessageStanzaType.CHAT || type == MessageStanzaType.NORMAL) {
            // private message
            logger.debug("Received direct message to {}", roomWithNickJid);
            Room room = conference.findRoom(roomJid);
            if (room == null) {
                return createMessageErrorStanza(moduleDomain, from, stanza.getID(), StanzaErrorType.MODIFY,
                        StanzaErrorCondition.ITEM_NOT_FOUND, stanza);
            }

            room.updateLastActivity();

            Occupant sendingOccupant = room.findOccupantByJID(from);

            // sender must be participant in room
            if (roomWithNickJid.equals(roomJid)) {
                // check x element

                if (stanza.getVerifier().onlySubelementEquals("x", NamespaceURIs.JABBER_X_DATA)) {
                    // voice requests
                    logger.debug("Received voice request for room {}", roomJid);

                    handleVoiceRequest(from, sendingOccupant, room, stanza, stanzaBroker);
                } else if (stanza.getVerifier().onlySubelementEquals("x", NamespaceURIs.XEP0045_MUC_USER)) {
                    // invites/declines
                    return handleInvites(stanza, from, sendingOccupant, room, stanzaBroker);
                }
            } else if (roomWithNickJid.isResourceSet()) {
                if (sendingOccupant == null) {
                    // user must be occupant to send direct message
                    return createMessageErrorStanza(room.getJID(), from, stanza.getID(), StanzaErrorType.MODIFY,
                            StanzaErrorCondition.NOT_ACCEPTABLE, stanza);
                }

                // got resource, private message for occupant
                Occupant receivingOccupant = room.findOccupantByNick(roomWithNickJid.getResource());

                // must be sent to an existing occupant in the room
                if (receivingOccupant == null) {
                    // TODO correct error?
                    return createMessageErrorStanza(moduleDomain, from, stanza.getID(), StanzaErrorType.MODIFY,
                            StanzaErrorCondition.ITEM_NOT_FOUND, stanza);
                }

                Entity roomAndSendingNick = new EntityImpl(room.getJID(), sendingOccupant.getNick());
                logger.debug("Relaying message to  {}", receivingOccupant);
                List<Attribute> replaceAttributes = new ArrayList<Attribute>();
                replaceAttributes.add(new Attribute("from", roomAndSendingNick.getFullQualifiedName()));
                replaceAttributes.add(new Attribute("to", receivingOccupant.getJid().getFullQualifiedName()));

                relayStanza(receivingOccupant.getJid(),
                        StanzaBuilder.createClone(stanza, true, replaceAttributes).build(), stanzaBroker);
            }
        }

        return Collections.emptyList();
    }