String field = settings.array().get(SuggestSettings.DefaultKeys.SUPPORTED_FIELDS)[0];

        Map<String, Object> document = new HashMap<>();
        document.put(field, "Sing the Supercalifragilisticexpialidocious for Honorificabilitudinitatibus");
        suggester.indexer().indexFromDocument(new Map[] { document });
        suggester.refresh();