private static void ensureInit() {
    if (cache != null) return;

    final Collection<NonCodeMembersContributor> allTypeContributors = new ArrayList<>();
    final MultiMap<String, NonCodeMembersContributor> contributorMap = new MultiMap<>();
    for (final NonCodeMembersContributor contributor : EP_NAME.getExtensions()) {
      Collection<String> fqns = contributor.getClassNames();
      if (fqns.isEmpty()) {
        allTypeContributors.add(contributor);
      }
      else {
        for (String fqn : fqns) {
          contributorMap.putValue(fqn, contributor);
        }
      }
    }
    cache = new Cache(contributorMap, allTypeContributors.toArray(new NonCodeMembersContributor[0]));
  }
private static void ensureInit()