public BasicNetworkConnectorTracker() 
{
        idToLocations = new HashMap< Object, Set< URI > >();
        nodeNameToLocations = new HashMap< String, Set< URI > >();
}

 public Set<URI> getConnectorURIs(Object deploymentId) throws NetworkConnectorTrackerException 
{
        Set< URI > locations;
        synchronized (idToLocations) {
            locations = idToLocations.get(deploymentId);
            if (null == locations) {
                throw new NetworkConnectorTrackerException("[" + deploymentId + "] is not registered");
            }
            locations = new HashSet< URI >(locations);
        }
        return locations;
}

 public  void registerNetworkConnectorLocations(Object deploymentId,
    String nodeName,
    Set<URI> locations) 
{
        synchronized (idToLocations) {
            Set< URI > allLocations = idToLocations.get(deploymentId);
            if (null == allLocations) {
                allLocations = new HashSet< URI >();
                idToLocations.put(deploymentId, allLocations);
            }
            allLocations.addAll(locations);
            allLocations = nodeNameToLocations.get(nodeName);
            if (null == allLocations) {
                allLocations = new HashSet< URI >();
                nodeNameToLocations.put(nodeName, allLocations);
            }
            allLocations.addAll(locations);
        }
}

 public  void unregisterNetworkConnectorLocations(String nodeName) 
{
        synchronized (idToLocations) {
            Set< URI > locationsToRemove = nodeNameToLocations.remove(nodeName);
            if (null == locationsToRemove) {
                return;
            }
            Map< Object, Set< URI > > clonedIdToLocations = new HashMap< Object, Set< URI > >(idToLocations);
            for (Map.Entry< Object, Set< URI > > entry : clonedIdToLocations.entrySet()) {
                Set< URI > allLocations = entry.getValue();
                allLocations.removeAll(locationsToRemove);
                if (allLocations.isEmpty()) {
                    idToLocations.remove(entry.getKey());
                }
            }
        }
}

 public  void unregisterNetworkConnectorLocations(Object deploymentId,
    String nodeName,
    Set<URI> locations) 
{
        synchronized (idToLocations) {
            Set< URI > allLocations = idToLocations.get(deploymentId);
            if (null == allLocations) {
                return;
            }
            allLocations.removeAll(locations);
            if (allLocations.isEmpty()) {
                idToLocations.remove(deploymentId);
            }
            allLocations = nodeNameToLocations.get(nodeName);
            allLocations.removeAll(locations);
            if (allLocations.isEmpty()) {
                nodeNameToLocations.remove(nodeName);
            }
        }
}