public Map<String,Integer> getNetworksIntersection(final Collection<Host> hosts) {
Optional<Map<String, Integer>> networksIntersection = Optional.absent();
for (final Host host : hosts) {
final HostNetworks hostNetworks = hostNetInterfacesByHost.get(host);
if (hostNetworks != null) {
networksIntersection = hostNetworks.getNetworksIntersection(networksIntersection);
}
}
return networksIntersection.or(new HashMap<String, Integer>());
}