code: public void addConverters(Converter converter, String... tags) {
          for (String tag : tags) {
              if (tag.startsWith("!")) {
                  notConverters.put(tag.substring(1), converter);
              } else {
                  converters.put(tag, converter);
              }
          }
      }
docs: Add the converter which should be used for a specific tag.
  
  @param tags tags for which the converter applies
  @param converter converter for the tag