}
final Set<Sponsor> sponsors = new HashSet<Sponsor>(detective.search(commitMessagesOf(buildData)));
if (sponsors.isEmpty()) {
for (String upstreamBuildUrl : buildData.upstreamBuildUrls()) {
sponsors.addAll(sponsorsOf(communicator.endpoint() + "/" + upstreamBuildUrl));
}
}
final Set<Sponsor> result = unmodifiableSet(sponsors);