static <T> T getOrCreateConverterInstance(Class<T> clazz) {
    //noinspection unchecked
    return (T)DomImplementationClassEP.CONVERTER_EP_NAME.computeIfAbsent(ConverterManagerImpl.class, () -> new MyClassValue()).get(clazz);
  }
static <T> T getOrCreateConverterInstance(Class<T> clazz)