private fun decodeIpv6(input: String): ByteArray? = decodeIpv6(input, 0, input.length)

  @Test
  fun testToCanonicalHost() {
    // IPv4
    assertThat("127.0.0.1".toCanonicalHost()).isEqualTo("127.0.0.1")
    assertThat("1.2.3.4".toCanonicalHost()).isEqualTo("1.2.3.4")

    // IPv6
    assertThat("::1".toCanonicalHost()).isEqualTo("::1")
    assertThat("2001:db8::1".toCanonicalHost()).isEqualTo("2001:db8::1")

     * @return IP address
     */
    public InetAddress getAddress() {
        return address;
    }

    /**
     * Check if this is an IPv6 address
     *
     * @return true if IPv6, false if IPv4
     */
    public boolean isIpv6() {
        return ipv6;
    }

    /**
     * Check if RSS is supported
     *
     * @return true if RSS capable
     */
    public boolean isRssCapable() {

    /** Kerberos protocol version */
    String KERBEROS_VERSION = "5";

    /** Kerberos AP-REQ message type */
    String KERBEROS_AP_REQ = "14";

    /** Address family: Internet (IPv4) */
    int AF_INTERNET = 2;
    /** Address family: CHANET */
    int AF_CHANET = 5;
    /** Address family: XNS */
    int AF_XNS = 6;
    /** Address family: ISO */
    int AF_ISO = 7;

 * [system DNS service][SYSTEM], which is the default. Some applications may provide their own
 * implementation to use a different DNS server, to prefer IPv6 addresses, to prefer IPv4 addresses,
 * or to force a specific known IP address.
 *
 * Implementations of this interface must be safe for concurrent use.
 */
fun interface Dns {
  /**

        IdnDnsResolver resolver = new IdnDnsResolver();

        // Test IPv6 loopback address with brackets
        String host = "[::1]";
        InetAddress[] addresses = resolver.resolve(host);
        assertNotNull(addresses);
        assertTrue(addresses.length > 0);
        // IPv6 loopback can be represented as ::1 or 0:0:0:0:0:0:0:1
        String hostAddress = addresses[0].getHostAddress();

  # Docker on Windows doesn't support the `host` networking mode, and so
  # port-forwarding is required for the container to detect it's running on GCE.
  export IP_ADDR=$(powershell -command "(Get-NetIPAddress -AddressFamily IPv4 -InterfaceAlias 'vEthernet (nat)').IPAddress")
  netsh interface portproxy add v4tov4 listenaddress=$IP_ADDR listenport=80 connectaddress=169.254.169.254 connectport=80
  # A local firewall rule for the container is added in

FESS_JAVA_OPTS="$FESS_JAVA_OPTS -Djava.awt.headless=true"

# maximum # keep-alive connections to maintain at once
FESS_JAVA_OPTS="$FESS_JAVA_OPTS -Dhttp.maxConnections=20"

# Force the JVM to use IPv4 stack
if [ "x$FESS_USE_IPV4" != "x" ]; then
  FESS_JAVA_OPTS="$FESS_JAVA_OPTS -Djava.net.preferIPv4Stack=true"
fi

# proxy
if [ "x$FESS_PROXY_HOST" != "x" ]; then

    /**
     * Checks if EPSV command should be used with IPv4.
     *
     * @return True if EPSV with IPv4 is enabled, false otherwise
     */
    public boolean isUseEPSVwithIPv4() {
        return useEPSVwithIPv4;
    }

    /**
     * Sets whether EPSV command should be used with IPv4.
     *
     * @param useEPSVwithIPv4 True to enable EPSV with IPv4, false to disable
     */

# Docker on Windows doesn't support the `host` networking mode, and so
# port-forwarding is required for the container to detect it's running on GCE.
export IP_ADDR=$(powershell -command "(Get-NetIPAddress -AddressFamily IPv4 -InterfaceAlias 'vEthernet (nat)').IPAddress")
netsh interface portproxy add v4tov4 listenaddress=$IP_ADDR listenport=80 connectaddress=169.254.169.254 connectport=80
# A local firewall rule for the container is added in

set FESS_JAVA_OPTS=%FESS_JAVA_OPTS% -Djava.awt.headless=true

REM maximum # keep-alive connections to maintain at once
set FESS_JAVA_OPTS=%FESS_JAVA_OPTS% -Dhttp.maxConnections=20

REM Force the JVM to use IPv4 stack
if NOT "%FESS_USE_IPV4%" == "" (
set FESS_JAVA_OPTS=%FESS_JAVA_OPTS% -Djava.net.preferIPv4Stack=true
)

REM proxy
if NOT "%FESS_PROXY_HOST%" == "" (