code: public static JsonNode getFieldValue(JsonNode doc, String field) {
          StringTokenizer tkz = new StringTokenizer(field, ". ");
          JsonNode trc = doc;
          while (tkz.hasMoreTokens() && trc != null) {
              String tok = tkz.nextToken();
              trc = trc.get(tok);
          }
          return trc;
      }
docs: Ooes not do array index lookup!