docs: public static String maskString(String input, String key) {
          String output = input;
          Map<String, Object> stringConfig = (Map<String, Object>) config.get(MASK_TYPE_STRING);
          if (stringConfig != null) {
              Map<String, Object> keyConfig = (Map<String, Object>) stringConfig.get(key);
              if (keyConfig != null) {
                  Set<String> patterns = keyConfig.keySet();
                  for (String pattern : patterns) {
                      output = output.replaceAll(pattern, (String) keyConfig.get(pattern));
                  }
              }
          }
          return output;
      }