System.setProperty("java.version", "15.0.1");

        String[] args = new String[] { "8-:-Xms512m", // From Java 8 onwards
                "11-:-Xmx2g", // From Java 11 onwards
                "17-:-XX:+UseG1GC", // From Java 17 onwards
                "21-:-XX:+UseZGC" // From Java 21 onwards
        };

        String[] result = JvmUtil.filterJvmOptions(args);
        assertEquals(2, result.length);

    return publicSuffixIndex() == 1;
  }

  /**
   * Returns the portion of this domain name that is one level beneath the {@linkplain
   * #isPublicSuffix() public suffix}. For example, for {@code x.adwords.google.co.uk} it returns
   * {@code google.co.uk}, since {@code co.uk} is a public suffix. Similarly, for {@code
   * myblog.blogspot.com} it returns the same domain, {@code myblog.blogspot.com}, since {@code

  }

  @Test
  fun topPrivateDomain() {
    assertThat("https://google.com".toHttpUrl().topPrivateDomain())
      .isEqualTo("google.com")
    assertThat("https://adwords.google.co.uk".toHttpUrl().topPrivateDomain())
      .isEqualTo("google.co.uk")
    assertThat("https://栃.栃木.jp".toHttpUrl().topPrivateDomain())
      .isEqualTo("xn--ewv.xn--4pvxs.jp")

    long rem = p - q * div; // equals p % q

    if (rem == 0) {
      return div;
    }

    /*
     * Normal Java division rounds towards 0, consistently with RoundingMode.DOWN. We just have to
     * deal with the cases where rounding towards 0 is wrong, which typically depends on the sign of
     * p / q.
     *
     * signum is 1 if p and q are both nonnegative or both negative, and -1 otherwise.
     */