docs: public void invalidateAll(Iterable<P> principals) {
          final Set<P> principalSet = Sets.of(principals);
          final Set<ImmutablePair<P, String>> keys = cache.asMap().keySet().stream()
                  .filter(cacheKey -> principalSet.contains(cacheKey.getLeft()))
                  .collect(Collectors.toSet());
          cache.invalidateAll(keys);
      }