for (String spec : GOOD_DOMAINS) {
      assertGood(spec);
    }
  }

  public void testBadDomains() {
    for (String spec : BAD_DOMAINS) {
      assertBad(spec);
    }
  }

  public void testEquality() {
    new EqualsTester()
        .addEqualityGroup(spec("1.2.3.4"), spec("1.2.3.4"))
        .addEqualityGroup(spec("2001:db8::1"), spec("2001:db8::1"), spec("[2001:db8::1]"))
        .addEqualityGroup(spec("2001:db8::2"))