List<String> (@NotNull Set<String> existingFields) { LinkedHashSet<String> result = new LinkedHashSet<>(); for (YamlMetaType next : myTypes) { if (next instanceof YamlScalarType) { continue; } List<String> nextMissing = next.computeMissingFields(existingFields); if (nextMissing.isEmpty()) { return Collections.emptyList(); } result.addAll(nextMissing); } return new LinkedList<>(result); }