protected Target pickBestBroker()

in activemq-partition/src/main/java/org/apache/activemq/partition/PartitionBroker.java [177:272]
81 lines of code
29 McCabe index (conditional complexity)

    protected Target pickBestBroker(ConnectionMonitor monitor) {

        if( getConfig() ==null )
            return null;

        if( getConfig().bySourceIp !=null && !getConfig().bySourceIp.isEmpty() ) {
            TransportConnection connection = (TransportConnection)monitor.context.getConnection();
            Transport transport = connection.getTransport();
            Socket socket = transport.narrow(Socket.class);
            if( socket !=null ) {
                SocketAddress address = socket.getRemoteSocketAddress();
                if( address instanceof InetSocketAddress) {
                    String ip = ((InetSocketAddress) address).getAddress().getHostAddress();
                    Target targetDTO = getConfig().bySourceIp.get(ip);
                    if( targetDTO!=null ) {
                        return targetDTO;
                    }
                }
            }
        }

        if( getConfig().byUserName !=null && !getConfig().byUserName.isEmpty() ) {
            String userName = monitor.context.getUserName();
            if( userName !=null ) {
                Target targetDTO = getConfig().byUserName.get(userName);
                if( targetDTO!=null ) {
                    return targetDTO;
                }
            }
        }

        if( getConfig().byClientId !=null && !getConfig().byClientId.isEmpty() ) {
            String clientId = monitor.context.getClientId();
            if( clientId!=null ) {
                Target targetDTO = getConfig().byClientId.get(clientId);
                if( targetDTO!=null ) {
                    return targetDTO;
                }
            }
        }

        if(
             (getConfig().byQueue !=null && !getConfig().byQueue.isEmpty())
          || (getConfig().byTopic !=null && !getConfig().byTopic.isEmpty())
          ) {

            // Collect the destinations the connection is consuming from...
            HashSet<ActiveMQDestination> dests = new HashSet<ActiveMQDestination>();
            for (SessionState session : monitor.context.getConnectionState().getSessionStates()) {
                for (ConsumerState consumer : session.getConsumerStates()) {
                    ActiveMQDestination destination = consumer.getInfo().getDestination();
                    if( destination.isComposite() ) {
                        dests.addAll(Arrays.asList(destination.getCompositeDestinations()));
                    } else {
                        dests.addAll(Collections.singletonList(destination));
                    }
                }
            }

            // Group them by the partitioning target for the destinations and score them..
            HashMap<Target, Score> targetScores = new HashMap<Target, Score>();
            for (ActiveMQDestination dest : dests) {
                Target target = getTarget(dest);
                if( target!=null ) {
                    Score score = targetScores.get(target);
                    if( score == null ) {
                        score = new Score();
                        targetScores.put(target, score);
                    }
                    score.value++;
                }
            }

            // The target with largest score wins..
            if (!targetScores.isEmpty()) {
                Target bestTarget = null;
                int bestScore = 0;
                for (Map.Entry<Target, Score> entry : targetScores.entrySet()) {
                    if (entry.getValue().value > bestScore) {
                        bestTarget = entry.getKey();
                        bestScore = entry.getValue().value;
                    }
                }
                return bestTarget;
            }

            // If we get here is because there were no consumers, or the destinations for those
            // consumers did not have an assigned destination..  So partition based on producer
            // usage.
            Target best = monitor.findBestProducerTarget(this);
            if( best!=null ) {
                return best;
            }
        }
        return null;
    }