protected Optional indexIfNeeded()

in src/main/java/com/ericsson/gerrit/plugins/highavailability/autoreindex/GroupReindexRunnable.java [71:121]
46 lines of code
5 McCabe index (conditional complexity)

  protected Optional<Timestamp> indexIfNeeded(GroupReference g, Timestamp sinceTs) {
    try {
      Optional<InternalGroup> internalGroup = groups.getGroup(g.getUUID());
      if (internalGroup.isPresent()) {
        InternalGroup group = internalGroup.get();
        Timestamp groupCreationTs = group.getCreatedOn();

        Repository allUsersRepo = repoManager.openRepository(allUsers);

        List<AccountGroupByIdAudit> subGroupMembersAud =
            groups.getSubgroupsAudit(allUsersRepo, g.getUUID());
        Stream<Timestamp> groupIdAudAddedTs =
            subGroupMembersAud.stream()
                .map(AccountGroupByIdAudit::addedOn)
                .filter(Objects::nonNull);
        Stream<Timestamp> groupIdAudRemovedTs =
            subGroupMembersAud.stream()
                .map(AccountGroupByIdAudit::removedOn)
                .filter(Optional<Timestamp>::isPresent)
                .map(Optional<Timestamp>::get);

        List<AccountGroupMemberAudit> groupMembersAud =
            groups.getMembersAudit(allUsersRepo, g.getUUID());
        Stream<Timestamp> groupMemberAudAddedTs =
            groupMembersAud.stream().map(AccountGroupMemberAudit::addedOn).filter(Objects::nonNull);
        Stream<Timestamp> groupMemberAudRemovedTs =
            groupMembersAud.stream()
                .map(AccountGroupMemberAudit::removedOn)
                .filter(Optional<Timestamp>::isPresent)
                .map(Optional<Timestamp>::get);

        Optional<Timestamp> groupLastTs =
            Streams.concat(
                    groupIdAudAddedTs,
                    groupIdAudRemovedTs,
                    groupMemberAudAddedTs,
                    groupMemberAudRemovedTs,
                    Stream.of(groupCreationTs))
                .max(Comparator.naturalOrder());

        if (groupLastTs.isPresent() && groupLastTs.get().after(sinceTs)) {
          log.atInfo().log("Index %s/%s/%s", g.getUUID(), g.getName(), groupLastTs.get());
          indexer.index(g.getUUID(), Operation.INDEX, Optional.empty());
          return groupLastTs;
        }
      }
    } catch (IOException | ConfigInvalidException e) {
      log.atSevere().withCause(e).log("Reindex failed");
    }
    return Optional.empty();
  }