IntegerTypeConverter implements TypeConverter<String, Integer> { @Override public Integer convert(final String value) { Utils.checkArgument(value != null, "Value to convert must not be null"); Utils.checkArgument(!value.isEmpty(), "Value to convert must not be empty"); return Double.valueOf(value).intValue(); }  @Override Integer convert(final String value);  }
@Test public void whenInputIsLegalValue_ThenShouldReturnInteger() { assertThat(converter.convert("5")).isNotNull(); assertThat(converter.convert("5")).isEqualTo(5); assertThat(converter.convert("5.0")).isEqualTo(5); }