  @Test
  public void testAdd() {

    // Let Java add it up
    long result = 10 + 23 + (-1) + 16;
    // Compare that to what the Matherator gives us
    assertEquals(result, classUnderTest.add(10, 23, -1, 16));

    result = 100 + 102;
    assertEquals(result, classUnderTest.add(100 + 102));

    result = 0;
    assertEquals(result, classUnderTest.add(0));

  }