code: public final <S, T> void registerConverter(Class<S> input, Class<T> output, Converter<S, T> converter) {
          Class<? extends Annotation> scope = matchImplementationToScope(converter.getClass());
          registerConverter(new ConverterKey<S,T>(input, output, scope == null ? DefaultBinding.class : scope), converter);
      }
docs: Register a Converter with the given input and output classes. Instances of the input class can be converted into
  instances of the output class
  @param input The input class
  @param output The output class
  @param converter The Converter to be registered