Refactor to separate api from implementation

Change-Id: Ia3ff3eab719cd380f502d359367e65835693ce12
diff --git a/app/src/main/java/org/opencord/cordmcast/impl/CordMcast.java b/app/src/main/java/org/opencord/cordmcast/impl/CordMcast.java
new file mode 100644
index 0000000..e014b79
--- /dev/null
+++ b/app/src/main/java/org/opencord/cordmcast/impl/CordMcast.java
@@ -0,0 +1,725 @@
+/*
+ * Copyright 2016-present Open Networking Foundation
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.opencord.cordmcast.impl;
+
+import com.google.common.collect.ImmutableSet;
+import com.google.common.collect.Sets;
+import org.apache.commons.lang3.tuple.ImmutablePair;
+import org.onlab.packet.Ethernet;
+import org.onlab.packet.IpAddress;
+import org.onlab.packet.VlanId;
+import org.onlab.util.KryoNamespace;
+import org.onosproject.cfg.ComponentConfigService;
+import org.onosproject.cluster.ClusterService;
+import org.onosproject.cluster.LeadershipService;
+import org.onosproject.cluster.NodeId;
+import org.onosproject.core.ApplicationId;
+import org.onosproject.core.CoreService;
+import org.onosproject.mastership.MastershipService;
+import org.onosproject.mcast.api.McastEvent;
+import org.onosproject.mcast.api.McastListener;
+import org.onosproject.mcast.api.McastRoute;
+import org.onosproject.mcast.api.MulticastRouteService;
+import org.onosproject.net.ConnectPoint;
+import org.onosproject.net.Device;
+import org.onosproject.net.DeviceId;
+import org.onosproject.net.HostId;
+import org.onosproject.net.PortNumber;
+import org.onosproject.net.config.ConfigFactory;
+import org.onosproject.net.config.NetworkConfigEvent;
+import org.onosproject.net.config.NetworkConfigListener;
+import org.onosproject.net.config.NetworkConfigRegistry;
+import org.onosproject.net.config.basics.McastConfig;
+import org.onosproject.net.config.basics.SubjectFactories;
+import org.onosproject.net.device.DeviceService;
+import org.onosproject.net.flow.DefaultTrafficSelector;
+import org.onosproject.net.flow.DefaultTrafficTreatment;
+import org.onosproject.net.flow.TrafficSelector;
+import org.onosproject.net.flowobjective.DefaultForwardingObjective;
+import org.onosproject.net.flowobjective.DefaultNextObjective;
+import org.onosproject.net.flowobjective.DefaultObjectiveContext;
+import org.onosproject.net.flowobjective.FlowObjectiveService;
+import org.onosproject.net.flowobjective.ForwardingObjective;
+import org.onosproject.net.flowobjective.NextObjective;
+import org.onosproject.net.flowobjective.Objective;
+import org.onosproject.net.flowobjective.ObjectiveContext;
+import org.onosproject.net.flowobjective.ObjectiveError;
+import org.onosproject.store.serializers.KryoNamespaces;
+import org.onosproject.store.service.ConsistentMap;
+import org.onosproject.store.service.Serializer;
+import org.onosproject.store.service.StorageService;
+import org.onosproject.store.service.Versioned;
+import org.opencord.cordmcast.CordMcastService;
+import org.opencord.cordmcast.CordMcastStatisticsService;
+import org.opencord.sadis.SadisService;
+import org.opencord.sadis.SubscriberAndDeviceInformation;
+import org.osgi.service.component.ComponentContext;
+import org.osgi.service.component.annotations.Activate;
+import org.osgi.service.component.annotations.Component;
+import org.osgi.service.component.annotations.Deactivate;
+import org.osgi.service.component.annotations.Modified;
+import org.osgi.service.component.annotations.Reference;
+import org.osgi.service.component.annotations.ReferenceCardinality;
+import org.slf4j.Logger;
+
+import java.util.Dictionary;
+import java.util.Map;
+import java.util.Objects;
+import java.util.Optional;
+import java.util.Properties;
+import java.util.Set;
+import java.util.concurrent.ExecutorService;
+import java.util.concurrent.locks.Lock;
+import java.util.concurrent.locks.ReentrantLock;
+
+import static com.google.common.base.Strings.isNullOrEmpty;
+import static java.util.concurrent.Executors.newSingleThreadScheduledExecutor;
+import static org.onlab.util.Tools.get;
+import static org.onlab.util.Tools.groupedThreads;
+import static org.opencord.cordmcast.impl.OsgiPropertyConstants.*;
+import static org.slf4j.LoggerFactory.getLogger;
+
+
+/**
+ * CORD multicast provisioning application. Operates by listening to
+ * events on the multicast rib and provisioning groups to program multicast
+ * flows on the dataplane.
+ */
+@Component(immediate = true,
+        property = {
+        VLAN_ENABLED + ":Boolean=" + DEFAULT_VLAN_ENABLED,
+        PRIORITY + ":Integer=" + DEFAULT_PRIORITY,
+})
+public class CordMcast implements CordMcastService {
+    private static final String APP_NAME = "org.opencord.mcast";
+
+    private final Logger log = getLogger(getClass());
+
+    private static final int DEFAULT_PRIORITY = 500;
+    private static final short DEFAULT_MCAST_VLAN = 4000;
+
+    @Reference(cardinality = ReferenceCardinality.MANDATORY)
+    protected MulticastRouteService mcastService;
+
+    @Reference(cardinality = ReferenceCardinality.MANDATORY)
+    protected FlowObjectiveService flowObjectiveService;
+
+    @Reference(cardinality = ReferenceCardinality.MANDATORY)
+    protected CoreService coreService;
+
+    @Reference(cardinality = ReferenceCardinality.MANDATORY)
+    protected ComponentConfigService componentConfigService;
+
+    @Reference(cardinality = ReferenceCardinality.MANDATORY)
+    protected NetworkConfigRegistry networkConfig;
+
+    @Reference(cardinality = ReferenceCardinality.MANDATORY)
+    protected StorageService storageService;
+
+    @Reference(cardinality = ReferenceCardinality.MANDATORY)
+    protected MastershipService mastershipService;
+
+    @Reference(cardinality = ReferenceCardinality.MANDATORY)
+    public DeviceService deviceService;
+
+    @Reference(cardinality = ReferenceCardinality.MANDATORY)
+    private ClusterService clusterService;
+
+    @Reference(cardinality = ReferenceCardinality.MANDATORY)
+    private LeadershipService leadershipService;
+
+    @Reference(cardinality = ReferenceCardinality.MANDATORY)
+    protected SadisService sadisService;
+
+    @Reference(cardinality = ReferenceCardinality.MANDATORY)
+    protected CordMcastStatisticsService cordMcastStatisticsService;
+
+    protected McastListener listener = new InternalMulticastListener();
+
+    private InternalNetworkConfigListener configListener =
+            new InternalNetworkConfigListener();
+
+    private ConsistentMap<NextKey, NextContent> groups;
+
+    private ApplicationId appId;
+    private ApplicationId coreAppId;
+    private short mcastVlan = DEFAULT_MCAST_VLAN;
+
+    /**
+     * Whether to use VLAN for multicast traffic.
+     **/
+    private boolean vlanEnabled = DEFAULT_VLAN_ENABLED;
+
+    /**
+     * Priority for multicast rules.
+     **/
+    private int priority = DEFAULT_PRIORITY;
+
+    private static final Class<McastConfig> CORD_MCAST_CONFIG_CLASS =
+            McastConfig.class;
+
+    private ConfigFactory<ApplicationId, McastConfig> cordMcastConfigFactory =
+            new ConfigFactory<ApplicationId, McastConfig>(
+                    SubjectFactories.APP_SUBJECT_FACTORY, CORD_MCAST_CONFIG_CLASS, "multicast") {
+                @Override
+                public McastConfig createConfig() {
+                    return new McastConfig();
+                }
+            };
+
+    // lock to synchronize local operations
+    private final Lock mcastLock = new ReentrantLock();
+    private void mcastLock() {
+        mcastLock.lock();
+    }
+    private void mcastUnlock() {
+        mcastLock.unlock();
+    }
+    private ExecutorService eventExecutor;
+
+    @Activate
+    public void activate(ComponentContext context) {
+        componentConfigService.registerProperties(getClass());
+        modified(context);
+
+        appId = coreService.registerApplication(APP_NAME);
+        coreAppId = coreService.registerApplication(CoreService.CORE_APP_NAME);
+
+        eventExecutor = newSingleThreadScheduledExecutor(groupedThreads("cord/mcast",
+                                                                        "events-mcast-%d", log));
+
+        KryoNamespace.Builder groupsKryo = new KryoNamespace.Builder()
+                .register(KryoNamespaces.API)
+                .register(NextKey.class)
+                .register(NextContent.class);
+        groups = storageService
+                .<NextKey, NextContent>consistentMapBuilder()
+                .withName("cord-mcast-groups-store")
+                .withSerializer(Serializer.using(groupsKryo.build("CordMcast-Groups")))
+                .build();
+
+        networkConfig.registerConfigFactory(cordMcastConfigFactory);
+        networkConfig.addListener(configListener);
+        mcastService.addListener(listener);
+
+        mcastService.getRoutes().stream()
+                .map(r -> new ImmutablePair<>(r, mcastService.sinks(r)))
+                .filter(pair -> pair.getRight() != null && !pair.getRight().isEmpty())
+                .forEach(pair -> pair.getRight().forEach(sink -> addSink(pair.getLeft(),
+                                                                          sink)));
+
+        McastConfig config = networkConfig.getConfig(coreAppId, CORD_MCAST_CONFIG_CLASS);
+        updateConfig(config);
+        log.info("Started");
+    }
+
+    @Modified
+    public void modified(ComponentContext context) {
+        Dictionary<?, ?> properties = context != null ? context.getProperties() : new Properties();
+
+        String s = get(properties, VLAN_ENABLED);
+        vlanEnabled = isNullOrEmpty(s) ? DEFAULT_VLAN_ENABLED : Boolean.parseBoolean(s.trim());
+
+        try {
+            s = get(properties, PRIORITY);
+            priority = isNullOrEmpty(s) ? DEFAULT_PRIORITY : Integer.parseInt(s.trim());
+        } catch (NumberFormatException ne) {
+            log.error("Unable to parse configuration parameter for priority", ne);
+            priority = DEFAULT_PRIORITY;
+        }
+        cordMcastStatisticsService.setVlanValue(assignedVlan());
+    }
+
+    @Deactivate
+    public void deactivate() {
+        componentConfigService.unregisterProperties(getClass(), false);
+        mcastService.removeListener(listener);
+        networkConfig.removeListener(configListener);
+        networkConfig.unregisterConfigFactory(cordMcastConfigFactory);
+        eventExecutor.shutdown();
+        clearGroups();
+        groups.destroy();
+        log.info("Stopped");
+    }
+
+    public void clearGroups() {
+        mcastLock();
+        try {
+            groups.keySet().forEach(groupInfo -> {
+                if (!isLocalLeader(groupInfo.getDevice())) {
+                    return;
+                }
+                NextContent next = groups.get(groupInfo).value();
+
+                if (next != null) {
+                    ObjectiveContext context = new DefaultObjectiveContext(
+                            (objective) -> log.debug("Successfully remove {}",
+                                                     groupInfo.group),
+                            (objective, error) -> log.warn("Failed to remove {}: {}",
+                                                           groupInfo.group, error));
+                    // remove the flow rule
+                    flowObjectiveService.forward(groupInfo.getDevice(), fwdObject(next.getNextId(),
+                                                                                  groupInfo.group).remove(context));
+                    // remove all ports from the group
+                    next.getOutPorts().stream().forEach(portNumber ->
+                        flowObjectiveService.next(groupInfo.getDevice(), nextObject(next.getNextId(),
+                                                                                    portNumber,
+                                                                                    NextType.RemoveFromExisting,
+                                                                                    groupInfo.group))
+                    );
+
+                }
+            });
+            groups.clear();
+        } finally {
+            mcastUnlock();
+        }
+    }
+
+    private VlanId multicastVlan() {
+        return VlanId.vlanId(mcastVlan);
+    }
+
+    protected VlanId assignedVlan() {
+        return vlanEnabled ? multicastVlan() : VlanId.NONE;
+    }
+
+    private class InternalMulticastListener implements McastListener {
+        @Override
+        public void event(McastEvent event) {
+            eventExecutor.execute(() -> {
+                switch (event.type()) {
+                    case ROUTE_ADDED:
+                    case ROUTE_REMOVED:
+                    case SOURCES_ADDED:
+                        break;
+                    case SINKS_ADDED:
+                        addSinks(event);
+                        break;
+                    case SINKS_REMOVED:
+                        removeSinks(event);
+                        break;
+                    default:
+                        log.warn("Unknown mcast event {}", event.type());
+                }
+            });
+        }
+    }
+
+    /**
+     * Processes previous, and new sinks then finds the sinks to be removed.
+     * @param prevSinks the previous sinks to be evaluated
+     * @param newSinks the new sinks to be evaluated
+     * @returnt the set of the sinks to be removed
+     */
+    private Set<ConnectPoint> getSinksToBeRemoved(Map<HostId, Set<ConnectPoint>> prevSinks,
+                                                  Map<HostId, Set<ConnectPoint>> newSinks) {
+        return getSinksToBeProcessed(prevSinks, newSinks);
+    }
+
+
+    /**
+     * Processes previous, and new sinks then finds the sinks to be added.
+     * @param newSinks the new sinks to be processed
+     * @param allPrevSinks all previous sinks
+     * @return the set of the sinks to be added
+     */
+    private Set<ConnectPoint> getSinksToBeAdded(Map<HostId, Set<ConnectPoint>> newSinks,
+                                                Map<HostId, Set<ConnectPoint>> allPrevSinks) {
+        return getSinksToBeProcessed(newSinks, allPrevSinks);
+    }
+
+    /**
+     * Gets single-homed sinks that are in set1 but not in set2.
+     * @param sinkSet1 the first sink map
+     * @param sinkSet2 the second sink map
+     * @return a set containing all the single-homed sinks found in set1 but not in set2
+     */
+    private Set<ConnectPoint> getSinksToBeProcessed(Map<HostId, Set<ConnectPoint>> sinkSet1,
+                                                    Map<HostId, Set<ConnectPoint>> sinkSet2) {
+        final Set<ConnectPoint> sinksToBeProcessed = Sets.newHashSet();
+        sinkSet1.forEach(((hostId, connectPoints) -> {
+            if (HostId.NONE.equals(hostId)) {
+                //assume all connect points associated with HostId.NONE are single homed sinks
+                sinksToBeProcessed.addAll(connectPoints);
+                return;
+            }
+        }));
+        Set<ConnectPoint> singleHomedSinksOfSet2 = sinkSet2.get(HostId.NONE) == null ?
+                Sets.newHashSet() :
+                sinkSet2.get(HostId.NONE);
+        return Sets.difference(sinksToBeProcessed, singleHomedSinksOfSet2);
+    };
+
+
+    private void removeSinks(McastEvent event) {
+        mcastLock();
+        try {
+            Set<ConnectPoint> sinksToBeRemoved = getSinksToBeRemoved(event.prevSubject().sinks(),
+                                                                     event.subject().sinks());
+            sinksToBeRemoved.forEach(sink -> removeSink(event.subject().route().group(), sink));
+        } finally {
+            mcastUnlock();
+        }
+    }
+
+    private void removeSink(IpAddress group, ConnectPoint sink) {
+        if (!isLocalLeader(sink.deviceId())) {
+            log.debug("Not the leader of {}. Skip sink_removed event for the sink {} and group {}",
+                      sink.deviceId(), sink, group);
+            return;
+        }
+
+        Optional<SubscriberAndDeviceInformation> oltInfo = getSubscriberAndDeviceInformation(sink.deviceId());
+
+        if (!oltInfo.isPresent()) {
+            log.warn("Unknown OLT device : {}", sink.deviceId());
+            return;
+        }
+
+        log.debug("Removing sink {} from the group {}", sink, group);
+
+        NextKey key = new NextKey(sink.deviceId(), group);
+        groups.computeIfPresent(key, (k, v) -> {
+            flowObjectiveService.next(sink.deviceId(), nextObject(v.getNextId(), sink.port(),
+                                                                  NextType.RemoveFromExisting, group));
+
+            Set<PortNumber> outPorts = Sets.newHashSet(v.getOutPorts());
+            outPorts.remove(sink.port());
+
+            if (outPorts.isEmpty()) {
+                // this is the last sink
+                ObjectiveContext context = new DefaultObjectiveContext(
+                        (objective) -> log.debug("Successfully remove {} on {}",
+                                                 group, sink),
+                        (objective, error) -> log.warn("Failed to remove {} on {}: {}",
+                                                       group, sink, error));
+                ForwardingObjective fwdObj = fwdObject(v.getNextId(), group).remove(context);
+                flowObjectiveService.forward(sink.deviceId(), fwdObj);
+            }
+            // remove the whole entity if no out port exists in the port list
+            return outPorts.isEmpty() ? null : new NextContent(v.getNextId(),
+                                                               ImmutableSet.copyOf(outPorts));
+        });
+    }
+
+    private void addSinks(McastEvent event) {
+        mcastLock();
+        try {
+            Set<ConnectPoint> sinksToBeAdded = getSinksToBeAdded(event.subject().sinks(),
+                                                                 event.prevSubject().sinks());
+            sinksToBeAdded.forEach(sink -> addSink(event.subject().route(), sink));
+        } finally {
+            mcastUnlock();
+        }
+    }
+
+    private void addSink(McastRoute route, ConnectPoint sink) {
+
+        if (!isLocalLeader(sink.deviceId())) {
+            log.debug("Not the leader of {}. Skip sink_added event for the sink {} and group {}",
+                      sink.deviceId(), sink, route.group());
+            return;
+        }
+
+        Optional<SubscriberAndDeviceInformation> oltInfo = getSubscriberAndDeviceInformation(sink.deviceId());
+
+        if (!oltInfo.isPresent()) {
+            log.warn("Unknown OLT device : {}", sink.deviceId());
+            return;
+        }
+
+        log.debug("Adding sink {} to the group {}", sink, route.group());
+
+        NextKey key = new NextKey(sink.deviceId(), route.group());
+        NextObjective newNextObj;
+
+        boolean theFirstSinkOfGroup = false;
+        if (!groups.containsKey(key)) {
+            // First time someone request this mcast group via this device
+            Integer nextId = flowObjectiveService.allocateNextId();
+            newNextObj = nextObject(nextId, sink.port(), NextType.AddNew, route.group());
+            // Store the new port
+            groups.put(key, new NextContent(nextId, ImmutableSet.of(sink.port())));
+            theFirstSinkOfGroup = true;
+        } else {
+            // This device already serves some subscribers of this mcast group
+            Versioned<NextContent> nextObj = groups.get(key);
+            if (nextObj.value().getOutPorts().contains(sink.port())) {
+                log.info("Group {} already serves the sink connected to {}", route.group(), sink);
+                return;
+            }
+            newNextObj = nextObject(nextObj.value().getNextId(), sink.port(),
+                                    NextType.AddToExisting, route.group());
+            // add new port to the group
+            Set<PortNumber> outPorts = Sets.newHashSet(nextObj.value().getOutPorts());
+            outPorts.add(sink.port());
+            groups.put(key, new NextContent(newNextObj.id(), ImmutableSet.copyOf(outPorts)));
+        }
+
+        ObjectiveContext context = new DefaultObjectiveContext(
+                (objective) -> log.debug("Successfully add {} on {}/{}, vlan {}",
+                                         route.group(), sink.deviceId(), sink.port().toLong(),
+                                         assignedVlan()),
+                (objective, error) -> {
+                    log.warn("Failed to add {} on {}/{}, vlan {}: {}",
+                             route.group(), sink.deviceId(), sink.port().toLong(), assignedVlan(),
+                             error);
+                });
+
+        flowObjectiveService.next(sink.deviceId(), newNextObj);
+
+        if (theFirstSinkOfGroup) {
+            // create the necessary flow rule if this is the first sink request for the group
+            // on this device
+            flowObjectiveService.forward(sink.deviceId(), fwdObject(newNextObj.id(),
+                                                                    route.group()).add(context));
+        }
+    }
+
+    /**
+     * Fetches device information associated with the device serial number from SADIS.
+     *
+     * @param serialNumber serial number of a device
+     * @return device information; an empty Optional otherwise.
+     */
+    private Optional<SubscriberAndDeviceInformation> getSubscriberAndDeviceInformation(String serialNumber) {
+        long start = System.currentTimeMillis();
+        try {
+            return Optional.ofNullable(sadisService.getSubscriberInfoService().get(serialNumber));
+        } finally {
+            if (log.isDebugEnabled()) {
+                // SADIS may call remote systems to fetch device data and this calls can take a long time.
+                // This measurement is just for monitoring these kinds of situations.
+                log.debug("Device fetched from SADIS. Elapsed {} msec", System.currentTimeMillis() - start);
+            }
+
+        }
+    }
+
+    /**
+     * Fetches device information associated with the device serial number from SADIS.
+     *
+     * @param deviceId device id
+     * @return device information; an empty Optional otherwise.
+     */
+    private Optional<SubscriberAndDeviceInformation> getSubscriberAndDeviceInformation(DeviceId deviceId) {
+        Device device = deviceService.getDevice(deviceId);
+        if (device == null || device.serialNumber() == null) {
+            return Optional.empty();
+        }
+        return getSubscriberAndDeviceInformation(device.serialNumber());
+    }
+
+    private class InternalNetworkConfigListener implements NetworkConfigListener {
+        @Override
+        public void event(NetworkConfigEvent event) {
+            eventExecutor.execute(() -> {
+                switch (event.type()) {
+
+                    case CONFIG_ADDED:
+                    case CONFIG_UPDATED:
+                        if (event.configClass().equals(CORD_MCAST_CONFIG_CLASS)) {
+                            McastConfig config = networkConfig.getConfig(coreAppId, CORD_MCAST_CONFIG_CLASS);
+                            if (config != null) {
+                                //TODO: Simply remove flows/groups, hosts will response period query
+                                // and re-sent IGMP report, so the flows can be rebuild.
+                                // However, better to remove and re-add mcast flow rules here
+                                if (mcastVlan != config.egressVlan().toShort() && vlanEnabled) {
+                                    clearGroups();
+                                }
+                                updateConfig(config);
+                            }
+                        }
+                        break;
+                    case CONFIG_REGISTERED:
+                    case CONFIG_UNREGISTERED:
+                    case CONFIG_REMOVED:
+                        break;
+                    default:
+                        break;
+                }
+            });
+        }
+    }
+
+    private void updateConfig(McastConfig config) {
+        if (config == null) {
+            return;
+        }
+        log.debug("multicast config received: {}", config);
+
+        if (config.egressVlan() != null) {
+            mcastVlan = config.egressVlan().toShort();
+        }
+    }
+
+    private class NextKey {
+        private DeviceId device;
+        private IpAddress group;
+
+        public NextKey(DeviceId deviceId, IpAddress groupAddress) {
+            device = deviceId;
+            group = groupAddress;
+        }
+
+        public DeviceId getDevice() {
+            return device;
+        }
+
+        public int hashCode() {
+            return Objects.hash(this.device, this.group);
+        }
+
+        public boolean equals(Object obj) {
+            if (this == obj) {
+                return true;
+            } else if (!(obj instanceof NextKey)) {
+                return false;
+            } else {
+                NextKey that = (NextKey) obj;
+                return this.getClass() == that.getClass() &&
+                        Objects.equals(this.device, that.device) &&
+                        Objects.equals(this.group, that.group);
+            }
+        }
+    }
+
+    private class NextContent {
+        private Integer nextId;
+        private Set<PortNumber> outPorts;
+
+        public NextContent(Integer nextId, Set<PortNumber> outPorts) {
+            this.nextId = nextId;
+            this.outPorts = outPorts;
+        }
+
+        public Integer getNextId() {
+            return nextId;
+        }
+
+        public Set<PortNumber> getOutPorts() {
+            return ImmutableSet.copyOf(outPorts);
+        }
+
+        public int hashCode() {
+            return Objects.hash(this.nextId, this.outPorts);
+        }
+
+        public boolean equals(Object obj) {
+            if (this == obj) {
+                return true;
+            } else if (!(obj instanceof NextContent)) {
+                return false;
+            } else {
+                NextContent that = (NextContent) obj;
+                return this.getClass() == that.getClass() &&
+                        Objects.equals(this.nextId, that.nextId) &&
+                        Objects.equals(this.outPorts, that.outPorts);
+            }
+        }
+    }
+
+    private enum NextType { AddNew, AddToExisting, Remove, RemoveFromExisting };
+
+    private NextObjective nextObject(Integer nextId, PortNumber port,
+                                     NextType nextType, IpAddress mcastIp) {
+
+        // Build the meta selector with the fwd objective info
+        TrafficSelector.Builder metadata = DefaultTrafficSelector.builder()
+                .matchIPDst(mcastIp.toIpPrefix());
+
+        if (vlanEnabled) {
+            metadata.matchVlanId(multicastVlan());
+        }
+
+        DefaultNextObjective.Builder build = DefaultNextObjective.builder()
+                .fromApp(appId)
+                .addTreatment(DefaultTrafficTreatment.builder().setOutput(port).build())
+                .withType(NextObjective.Type.BROADCAST)
+                .withId(nextId)
+                .withMeta(metadata.build());
+
+        ObjectiveContext content = new ObjectiveContext() {
+            @Override
+            public void onSuccess(Objective objective) {
+                log.debug("Next Objective {} installed", objective.id());
+            }
+
+            @Override
+            public void onError(Objective objective, ObjectiveError error) {
+                log.debug("Next Objective {} failed, because {}",
+                          objective.id(),
+                          error);
+            }
+        };
+
+        switch (nextType) {
+            case AddNew:
+                return build.add(content);
+            case AddToExisting:
+                return build.addToExisting(content);
+            case Remove:
+                return build.remove(content);
+            case RemoveFromExisting:
+                return build.removeFromExisting(content);
+            default:
+                return null;
+        }
+    }
+
+    private ForwardingObjective.Builder fwdObject(int nextId, IpAddress mcastIp) {
+        TrafficSelector.Builder mcast = DefaultTrafficSelector.builder()
+                .matchEthType(Ethernet.TYPE_IPV4)
+                .matchIPDst(mcastIp.toIpPrefix());
+
+        //build the meta selector
+        TrafficSelector.Builder metabuilder = DefaultTrafficSelector.builder();
+        if (vlanEnabled) {
+            metabuilder.matchVlanId(multicastVlan());
+        }
+
+        ForwardingObjective.Builder fwdBuilder = DefaultForwardingObjective.builder()
+                .fromApp(appId)
+                .nextStep(nextId)
+                .makePermanent()
+                .withFlag(ForwardingObjective.Flag.SPECIFIC)
+                .withPriority(priority)
+                .withSelector(mcast.build())
+                .withMeta(metabuilder.build());
+
+        return fwdBuilder;
+    }
+
+    // Custom-built function, when the device is not available we need a fallback mechanism
+    private boolean isLocalLeader(DeviceId deviceId) {
+        if (!mastershipService.isLocalMaster(deviceId)) {
+            // When the device is available we just check the mastership
+            if (deviceService.isAvailable(deviceId)) {
+                return false;
+            }
+            // Fallback with Leadership service - device id is used as topic
+            NodeId leader = leadershipService.runForLeadership(
+                    deviceId.toString()).leaderNodeId();
+            // Verify if this node is the leader
+            return clusterService.getLocalNode().id().equals(leader);
+        }
+        return true;
+    }
+
+}
+
+