Parking { public boolean unparkCar(final int index) { throw new NotImplementedException("TODO"); }  int getAvailableBays(); int parkCar(final char carType); boolean unparkCar(final int index); @Override String toString();  }
@Test public void testUnparkCar() { final int firstCarBayIndex = parking.parkCar('C'); assertTrue(parking.unparkCar(firstCarBayIndex)); assertEquals(23, parking.getAvailableBays()); assertFalse(parking.unparkCar(firstCarBayIndex)); final int secondCarBayIndex = parking.parkCar('D'); assertTrue(parking.unparkCar(secondCarBayIndex)); assertEquals(23, parking.getAvailableBays()); assertFalse(parking.unparkCar(secondCarBayIndex)); assertFalse(parking.unparkCar(FIRSTUPEDESTRIANUEXITUINDEX)); }