public void testFrom() {
    Function<String, Integer> forward =
        new Function<String, Integer>() {
          @Override
          public Integer apply(String input) {
            return Integer.parseInt(input);
          }
        };
    Function<Object, String> backward = toStringFunction();

    Converter<String, Number> converter = Converter.<String, Number>from(forward, backward);

  public void testFrom() {
    Function<String, Integer> forward =
        new Function<String, Integer>() {
          @Override
          public Integer apply(String input) {
            return Integer.parseInt(input);
          }
        };
    Function<Object, String> backward = toStringFunction();

    Converter<String, Number> converter = Converter.<String, Number>from(forward, backward);