@Test
 public void constructFromRomanNumeral() {
   // Given
   RomanNumeral romanNumeral = new RomanNumeral("IV");
   // Then
   assertThat(romanNumeral.getNumericValue(), is(equalTo(4)));
   assertThat(romanNumeral.getRoman(), is(equalTo("IV")));
 }
 @Test
 public void constructFromIntegerString() {
   RomanNumeral romanNumeral = new RomanNumeral("4");
   assertThat(romanNumeral.getRoman(), is(equalTo("IV")));
   assertThat(romanNumeral.getNumericValue(), is(equalTo(4)));
 }