@Test
public void testEqualsContract() {
IBAN x = IBAN.parse(VALID_IBAN);
IBAN y = IBAN.parse(VALID_IBAN);
IBAN z = IBAN.parse(VALID_IBAN);
assertFalse("No object equals null", x.equals(null));
assertTrue("An object equals itself", x.equals(x));
assertTrue("Equality is symmetric", x.equals(y) && y.equals(x));
assertTrue("Equality is transitive", x.equals(y) && y.equals(z) && x.equals(z));
assertEquals("Equal objects have the same hash code", x.hashCode(), y.hashCode());
}
