/*
 * Copyright (c) 2000, 2018, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 *
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 *
 */

package java.net;

import java.io.IOException;
import java.io.InvalidObjectException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.io.ObjectStreamField;
import java.util.Enumeration;
import java.util.Arrays;

/**
 * This class represents an Internet Protocol version 6 (IPv6) address.
 * Defined by <a href="http://www.ietf.org/rfc/rfc2373.txt">
 * <i>RFC&nbsp;2373: IP Version 6 Addressing Architecture</i></a>.
 *
 * <h3> <a id="format">Textual representation of IP addresses</a> </h3>
 *
 * Textual representation of IPv6 address used as input to methods
 * takes one of the following forms:
 *
 * <ol>
 * <li><p> <a id="lform">The preferred form</a> is x:x:x:x:x:x:x:x,
 * where the 'x's are
 * the hexadecimal values of the eight 16-bit pieces of the
 * address. This is the full form. For example,
 *
 * <blockquote><ul style="list-style-type:none">
 * <li>{@code .&checktime(1080,0,0,':'):0:8:800:200C:417A}</li>
 * </ul></blockquote>
 *
 * <p> Note that it is not necessary to write the leading zeros in
 * an individual field. However, there must be at least one numeral
 * in every field, except as described below.</li>
 *
 * <li><p> Due to some methods of allocating certain styles of IPv6
 * addresses, it will be common for addresses to contain long
 * strings of zero bits. In order to make writing addresses
 * containing zero bits easier, a special syntax is available to
 * compress the zeros. The use of "::" indicates multiple groups
 * of 16-bits of zeros. The "::" can only appear once in an address.
 * The "::" can also be used to compress the leading and/or trailing
 * zeros in an address. For example,
 *
 * <blockquote><ul style="list-style-type:none">
 * <li>{@code 1080::8:800:200C:417A}</li>
 * </ul></blockquote>
 *
 * <li><p> An alternative form that is sometimes more convenient
 * when dealing with a mixed environment of IPv4 and IPv6 nodes is
 * x:x:x:x:x:x:d.d.d.d, where the 'x's are the hexadecimal values
 * of the six high-order 16-bit pieces of the address, and the 'd's
 * are the decimal values of the four low-order 8-bit pieces of the
 * standard IPv4 representation address, for example,
 *
 * <blockquote><ul style="list-style-type:none">
 * <li>{@code ::FFFF:129.144.52.38}</li>
 * <li>{@code ::129.144.52.38}</li>
 * </ul></blockquote>
 *
 * <p> where "::FFFF:d.d.d.d" and "::d.d.d.d" are, respectively, the
 * general forms of an IPv4-mapped IPv6 address and an
 * IPv4-compatible IPv6 address. Note that the IPv4 portion must be
 * in the "d.d.d.d" form. The following forms are invalid:
 *
 * <blockquote><ul style="list-style-type:none">
 * <li>{@code ::FFFF:d.d.d}</li>
 * <li>{@code ::FFFF:d.d}</li>
 * <li>{@code ::d.d.d}</li>
 * <li>{@code ::d.d}</li>
 * </ul></blockquote>
 *
 * <p> The following form:
 *
 * <blockquote><ul style="list-style-type:none">
 * <li>{@code ::FFFF:d}</li>
 * </ul></blockquote>
 *
 * <p> is valid, however it is an unconventional representation of
 * the IPv4-compatible IPv6 address,
 *
 * <blockquote><ul style="list-style-type:none">
 * <li>{@code ::255.255.0.d}</li>
 * </ul></blockquote>
 *
 * <p> while "::d" corresponds to the general IPv6 address
 * "0:0:0:0:0:0:0:d".</li>
 * </ol>
 *
 * <p> For methods that return a textual representation as output
 * value, the full form is used. Inet6Address will return the full
 * form because it is unambiguous when used in combination with other
 * textual data.
 *
 * <h4> Special IPv6 address </h4>
 *
 * <blockquote>
 * <table class="borderless">
 * <caption style="display:none">Description of IPv4-mapped address</caption>
 * <tr><th style="vertical-align:top; padding-right:2px"><i>IPv4-mapped address</i></th>
 * <td>Of the form ::ffff:w.x.y.z, this IPv6 address is used to
 * represent an IPv4 address. It allows the native program to
 * use the same address data structure and also the same
 * socket when communicating with both IPv4 and IPv6 nodes.
 *
 * <p>In InetAddress and Inet6Address, it is used for internal
 * representation; it has no functional role. Java will never
 * return an IPv4-mapped address. These classes can take an
 * IPv4-mapped address as input, both in byte array and text
 * representation. However, it will be converted into an IPv4
 * address.</td></tr>
 * </table></blockquote>
 *
 * <h4><a id="scoped">Textual representation of IPv6 scoped addresses</a></h4>
 *
 * <p> The textual representation of IPv6 addresses as described above can be
 * extended to specify IPv6 scoped addresses. This extension to the basic
 * addressing architecture is described in [draft-ietf-ipngwg-scoping-arch-04.txt].
 *
 * <p> Because link-local and site-local addresses are non-global, it is possible
 * that different hosts may have the same destination address and may be
 * reachable through different interfaces on the same originating system. In
 * this case, the originating system is said to be connected to multiple zones
 * of the same scope. In order to disambiguate which is the intended destination
 * zone, it is possible to append a zone identifier (or <i>scope_id</i>) to an
 * IPv6 address.
 *
 * <p> The general format for specifying the <i>scope_id</i> is the following:
 *
 * <blockquote><i>IPv6-address</i>%<i>scope_id</i></blockquote>
 * <p> The IPv6-address is a literal IPv6 address as described above.
 * The <i>scope_id</i> refers to an interface on the local system, and it can be
 * specified in two ways.
 * <ol><li><i>As a numeric identifier.</i> This must be a positive integer
 * that identifies the particular interface and scope as understood by the
 * system. Usually, the numeric values can be determined through administration
 * tools on the system. Each interface may have multiple values, one for each
 * scope. If the scope is unspecified, then the default value used is zero.</li>
 * <li><i>As a string.</i> This must be the exact string that is returned by
 * {@link java.net.NetworkInterface#getName()} for the particular interface in
 * question. When an Inet6Address is created in this way, the numeric scope-id
 * is determined at the time the object is created by querying the relevant
 * NetworkInterface.</li></ol>
 *
 * <p> Note also, that the numeric <i>scope_id</i> can be retrieved from
 * Inet6Address instances returned from the NetworkInterface class. This can be
 * used to find out the current scope ids configured on the system.
 * @since 1.4
 */

public final
class Inet6Address extends InetAddress {
 static final int INADDRSZ = 16;

 /*
 * cached scope_id - for link-local address use only.
 */
 private transient int cached_scope_id; // 0

 private class Inet6AddressHolder {

 private Inet6AddressHolder() {
 ipaddress = new byte[INADDRSZ];
 }

 private Inet6AddressHolder(
 byte[] ipaddress, int scope_id, boolean scope_id_set,
 NetworkInterface ifname, boolean scope_ifname_set)
 {
 this.ipaddress = ipaddress;
 this.scope_id = scope_id;
 this.scope_id_set = scope_id_set;
 this.scope_ifname_set = scope_ifname_set;
 this.scope_ifname = ifname;
 }

 /**
 * Holds a 128-bit (16 bytes) IPv6 address.
 */
 byte[] ipaddress;

 /**
 * scope_id. The scope specified when the object is created. If the object
 * is created with an interface name, then the scope_id is not determined
 * until the time it is needed.
 */
 int scope_id; // 0

 /**
 * This will be set to true when the scope_id field contains a valid
 * integer scope_id.
 */
 boolean scope_id_set; // false

 /**
 * scoped interface. scope_id is derived from this as the scope_id of the first
 * address whose scope is the same as this address for the named interface.
 */
 NetworkInterface scope_ifname; // null

 /**
 * set if the object is constructed with a scoped
 * interface instead of a numeric scope id.
 */
 boolean scope_ifname_set; // false;

 void setAddr(byte addr[]) {
 if (addr.length == INADDRSZ) { // normal IPv6 address
 System.arraycopy(addr, 0, ipaddress, 0, INADDRSZ);
 }
 }

 void init(byte addr[], int scope_id) {
 setAddr(addr);

 if (scope_id >= 0) {
 this.scope_id = scope_id;
 this.scope_id_set = true;
 }
 }

 void init(byte addr[], NetworkInterface nif)
 throws UnknownHostException
 {
 setAddr(addr);

 if (nif != null) {
 this.scope_id = deriveNumericScope(ipaddress, nif);
 this.scope_id_set = true;
 this.scope_ifname = nif;
 this.scope_ifname_set = true;
 }
 }

 String getHostAddress() {
 String s = numericToTextFormat(ipaddress);
 if (scope_ifname != null) { /* must check this first */
 s = s + "%" + scope_ifname.getName();
 } else if (scope_id_set) {
 s = s + "%" + scope_id;
 }
 return s;
 }

 public boolean equals(Object o) {
 if (! (o instanceof Inet6AddressHolder)) {
 return false;
 }
 Inet6AddressHolder that = (Inet6AddressHolder)o;

 return Arrays.equals(this.ipaddress, that.ipaddress);
 }

 public int hashCode() {
 if (ipaddress != null) {

 int hash = 0;
 int i=0;
 while (i<INADDRSZ) {
 int j=0;
 int component=0;
 while (j<4 && i<INADDRSZ) {
 component = (component << 8) + ipaddress[i];
 j++;
 i++;
 }
 hash += component;
 }
 return hash;

 } else {
 return 0;
 }
 }

 boolean isIPv4CompatibleAddress() {
 if ((ipaddress[0] == 0x00) && (ipaddress[1] == 0x00) &&
 (ipaddress[2] == 0x00) && (ipaddress[3] == 0x00) &&
 (ipaddress[4] == 0x00) && (ipaddress[5] == 0x00) &&
 (ipaddress[6] == 0x00) && (ipaddress[7] == 0x00) &&
 (ipaddress[8] == 0x00) && (ipaddress[9] == 0x00) &&
 (ipaddress[10] == 0x00) && (ipaddress[11] == 0x00)) {
 return true;
 }
 return false;
 }

 boolean isMulticastAddress() {
 return ((ipaddress[0] & 0xff) == 0xff);
 }

 boolean isAnyLocalAddress() {
 byte test = 0x00;
 for (int i = 0; i < INADDRSZ; i++) {
 test |= ipaddress[i];
 }
 return (test == 0x00);
 }

 boolean isLoopbackAddress() {
 byte test = 0x00;
 for (int i = 0; i < 15; i++) {
 test |= ipaddress[i];
 }
 return (test == 0x00) && (ipaddress[15] == 0x01);
 }

 boolean isLinkLocalAddress() {
 return ((ipaddress[0] & 0xff) == 0xfe
 && (ipaddress[1] & 0xc0) == 0x80);
 }


 boolean isSiteLocalAddress() {
 return ((ipaddress[0] & 0xff) == 0xfe
 && (ipaddress[1] & 0xc0) == 0xc0);
 }

 boolean isMCGlobal() {
 return ((ipaddress[0] & 0xff) == 0xff
 && (ipaddress[1] & 0x0f) == 0x0e);
 }

 boolean isMCNodeLocal() {
 return ((ipaddress[0] & 0xff) == 0xff
 && (ipaddress[1] & 0x0f) == 0x01);
 }

 boolean isMCLinkLocal() {
 return ((ipaddress[0] & 0xff) == 0xff
 && (ipaddress[1] & 0x0f) == 0x02);
 }

 boolean isMCSiteLocal() {
 return ((ipaddress[0] & 0xff) == 0xff
 && (ipaddress[1] & 0x0f) == 0x05);
 }

 boolean isMCOrgLocal() {
 return ((ipaddress[0] & 0xff) == 0xff
 && (ipaddress[1] & 0x0f) == 0x08);
 }
 }

 private final transient Inet6AddressHolder holder6;

 private static final long serialVersionUID = 6880410070516793377L;

 // Perform native initialization
 static { init(); }

 Inet6Address() {
 super();
 holder.init(null, IPv6);
 holder6 = new Inet6AddressHolder();
 }

 /* checking of value for scope_id should be done by caller
 * scope_id must be >= 0, or -1 to indicate not being set
 */
 Inet6Address(String hostName, byte addr[], int scope_id) {
 holder.init(hostName, IPv6);
 holder6 = new Inet6AddressHolder();
 holder6.init(addr, scope_id);
 }

 Inet6Address(String hostName, byte addr[]) {
 holder6 = new Inet6AddressHolder();
 try {
 initif (hostName, addr, null);
 } catch (UnknownHostException e) {} /* cant happen if ifname is null */
 }

 Inet6Address (String hostName, byte addr[], NetworkInterface nif)
 throws UnknownHostException
 {
 holder6 = new Inet6AddressHolder();
 initif (hostName, addr, nif);
 }

 Inet6Address (String hostName, byte addr[], String ifname)
 throws UnknownHostException
 {
 holder6 = new Inet6AddressHolder();
 initstr (hostName, addr, ifname);
 }

 /**
 * Create an Inet6Address in the exact manner of {@link
 * InetAddress#getByAddress(String,byte[])} except that the IPv6 scope_id is
 * set to the value corresponding to the given interface for the address
 * type specified in {@code addr}. The call will fail with an
 * UnknownHostException if the given interface does not have a numeric
 * scope_id assigned for the given address type (eg. link-local or site-local).
 * See <a href="Inet6Address.html#scoped">here</a> for a description of IPv6
 * scoped addresses.
 *
 * @param host the specified host
 * @param addr the raw IP address in network byte order
 * @param nif an interface this address must be associated with.
 * @return an Inet6Address object created from the raw IP address.
 * @throws UnknownHostException
 * if IP address is of illegal length, or if the interface does not
 * have a numeric scope_id assigned for the given address type.
 *
 * @since 1.5
 */
 public static Inet6Address getByAddress(String host, byte[] addr,
 NetworkInterface nif)
 throws UnknownHostException
 {
 if (host != null && host.length() > 0 && host.charAt(0) == '[') {
 if (host.charAt(host.length()-1) == ']') {
 host = host.substring(1, host.length() -1);
 }
 }
 if (addr != null) {
 if (addr.length == Inet6Address.INADDRSZ) {
 return new Inet6Address(host, addr, nif);
 }
 }
 throw new UnknownHostException("addr is of illegal length");
 }

 /**
 * Create an Inet6Address in the exact manner of {@link
 * InetAddress#getByAddress(String,byte[])} except that the IPv6 scope_id is
 * set to the given numeric value. The scope_id is not checked to determine
 * if it corresponds to any interface on the system.
 * See <a href="Inet6Address.html#scoped">here</a> for a description of IPv6
 * scoped addresses.
 *
 * @param host the specified host
 * @param addr the raw IP address in network byte order
 * @param scope_id the numeric scope_id for the address.
 * @return an Inet6Address object created from the raw IP address.
 * @throws UnknownHostException if IP address is of illegal length.
 *
 * @since 1.5
 */
 public static Inet6Address getByAddress(String host, byte[] addr,
 int scope_id)
 throws UnknownHostException
 {
 if (host != null && host.length() > 0 && host.charAt(0) == '[') {
 if (host.charAt(host.length()-1) == ']') {
 host = host.substring(1, host.length() -1);
 }
 }
 if (addr != null) {
 if (addr.length == Inet6Address.INADDRSZ) {
 return new Inet6Address(host, addr, scope_id);
 }
 }
 throw new UnknownHostException("addr is of illegal length");
 }

 private void initstr(String hostName, byte addr[], String ifname)
 throws UnknownHostException
 {
 try {
 NetworkInterface nif = NetworkInterface.getByName (ifname);
 if (nif == null) {
 throw new UnknownHostException ("no such interface " + ifname);
 }
 initif (hostName, addr, nif);
 } catch (SocketException e) {
 throw new UnknownHostException ("SocketException thrown" + ifname);
 }
 }

 private void initif(String hostName, byte addr[], NetworkInterface nif)
 throws UnknownHostException
 {
 int family = -1;
 holder6.init(addr, nif);

 if (addr.length == INADDRSZ) { // normal IPv6 address
 family = IPv6;
 }
 holder.init(hostName, family);
 }

 /* check the two Ipv6 addresses and return false if they are both
 * non global address types, but not the same.
 * (ie. one is sitelocal and the other linklocal)
 * return true otherwise.
 */

 private static boolean isDifferentLocalAddressType(
 byte[] thisAddr, byte[] otherAddr) {

 if (Inet6Address.isLinkLocalAddress(thisAddr) &&
 !Inet6Address.isLinkLocalAddress(otherAddr)) {
 return false;
 }
 if (Inet6Address.isSiteLocalAddress(thisAddr) &&
 !Inet6Address.isSiteLocalAddress(otherAddr)) {
 return false;
 }
 return true;
 }

 private static int deriveNumericScope (byte[] thisAddr, NetworkInterface ifc) throws UnknownHostException {
 Enumeration<InetAddress> addresses = ifc.getInetAddresses();
 while (addresses.hasMoreElements()) {
 InetAddress addr = addresses.nextElement();
 if (!(addr instanceof Inet6Address)) {
 continue;
 }
 Inet6Address ia6_addr = (Inet6Address)addr;
 /* check if site or link local prefixes match */
 if (!isDifferentLocalAddressType(thisAddr, ia6_addr.getAddress())){
 /* type not the same, so carry on searching */
 continue;
 }
 /* found a matching address - return its scope_id */
 return ia6_addr.getScopeId();
 }
 throw new UnknownHostException ("no scope_id found");
 }

 private int deriveNumericScope (String ifname) throws UnknownHostException {
 Enumeration<NetworkInterface> en;
 try {
 en = NetworkInterface.getNetworkInterfaces();
 } catch (SocketException e) {
 throw new UnknownHostException ("could not enumerate local network interfaces");
 }
 while (en.hasMoreElements()) {
 NetworkInterface ifc = en.nextElement();
 if (ifc.getName().equals (ifname)) {
 return deriveNumericScope(holder6.ipaddress, ifc);
 }
 }
 throw new UnknownHostException ("No matching address found for interface : " +ifname);
 }

 /**
 * @serialField ipaddress byte[]
 * @serialField scope_id int
 * @serialField scope_id_set boolean
 * @serialField scope_ifname_set boolean
 * @serialField ifname String
 */

 private static final ObjectStreamField[] serialPersistentFields = {
 new ObjectStreamField("ipaddress", byte[].class),
 new ObjectStreamField("scope_id", int.class),
 new ObjectStreamField("scope_id_set", boolean.class),
 new ObjectStreamField("scope_ifname_set", boolean.class),
 new ObjectStreamField("ifname", String.class)
 };

 private static final jdk.internal.misc.Unsafe UNSAFE
 = jdk.internal.misc.Unsafe.getUnsafe();
 private static final long FIELDS_OFFSET = UNSAFE.objectFieldOffset(
 Inet6Address.class, "holder6");

 /**
 * restore the state of this object from stream
 * including the scope information, only if the
 * scoped interface name is valid on this system
 */
 private void readObject(ObjectInputStream s)
 throws IOException, ClassNotFoundException {
 NetworkInterface scope_ifname = null;

 if (getClass().getClassLoader() != null) {
 throw new SecurityException ("invalid address type");
 }

 ObjectInputStream.GetField gf = s.readFields();
 byte[] ipaddress = (byte[])gf.get("ipaddress", new byte[0]);
 int scope_id = gf.get("scope_id", -1);
 boolean scope_id_set = gf.get("scope_id_set", false);
 boolean scope_ifname_set = gf.get("scope_ifname_set", false);
 String ifname = (String)gf.get("ifname", null);

 if (ifname != null && !"".equals (ifname)) {
 try {
 scope_ifname = NetworkInterface.getByName(ifname);
 if (scope_ifname == null) {
 /* the interface does not exist on this system, so we clear
 * the scope information completely */
 scope_id_set = false;
 scope_ifname_set = false;
 scope_id = 0;
 } else {
 scope_ifname_set = true;
 try {
 scope_id = deriveNumericScope (ipaddress, scope_ifname);
 } catch (UnknownHostException e) {
 // typically should not happen, but it may be that
 // the machine being used for deserialization has
 // the same interface name but without IPv6 configured.
 }
 }
 } catch (SocketException e) {}
 }

 /* if ifname was not supplied, then the numeric info is used */

 ipaddress = ipaddress.clone();

 // Check that our invariants are satisfied
 if (ipaddress.length != INADDRSZ) {
 throw new InvalidObjectException("invalid address length: "+
 ipaddress.length);
 }

 if (holder.getFamily() != IPv6) {
 throw new InvalidObjectException("invalid address family type");
 }

 Inet6AddressHolder h = new Inet6AddressHolder(
 ipaddress, scope_id, scope_id_set, scope_ifname, scope_ifname_set
 );

 UNSAFE.putObject(this, FIELDS_OFFSET, h);
 }

 /**
 * default behavior is overridden in order to write the
 * scope_ifname field as a String, rather than a NetworkInterface
 * which is not serializable
 */
 private synchronized void writeObject(ObjectOutputStream s)
 throws IOException
 {
 String ifname = null;

 if (holder6.scope_ifname != null) {
 ifname = holder6.scope_ifname.getName();
 holder6.scope_ifname_set = true;
 }
 ObjectOutputStream.PutField pfields = s.putFields();
 pfields.put("ipaddress", holder6.ipaddress);
 pfields.put("scope_id", holder6.scope_id);
 pfields.put("scope_id_set", holder6.scope_id_set);
 pfields.put("scope_ifname_set", holder6.scope_ifname_set);
 pfields.put("ifname", ifname);
 s.writeFields();
 }

 /**
 * Utility routine to check if the InetAddress is an IP multicast
 * address. 11111111 at the start of the address identifies the
 * address as being a multicast address.
 *
 * @return a {@code boolean} indicating if the InetAddress is an IP
 * multicast address
 */
 @Override
 public boolean isMulticastAddress() {
 return holder6.isMulticastAddress();
 }

 /**
 * Utility routine to check if the InetAddress is a wildcard address.
 *
 * @return a {@code boolean} indicating if the Inetaddress is
 * a wildcard address.
 */
 @Override
 public boolean isAnyLocalAddress() {
 return holder6.isAnyLocalAddress();
 }

 /**
 * Utility routine to check if the InetAddress is a loopback address.
 *
 * @return a {@code boolean} indicating if the InetAddress is a loopback
 * address; or false otherwise.
 */
 @Override
 public boolean isLoopbackAddress() {
 return holder6.isLoopbackAddress();
 }

 /**
 * Utility routine to check if the InetAddress is an link local address.
 *
 * @return a {@code boolean} indicating if the InetAddress is a link local
 * address; or false if address is not a link local unicast address.
 */
 @Override
 public boolean isLinkLocalAddress() {
 return holder6.isLinkLocalAddress();
 }

 /* static version of above */
 static boolean isLinkLocalAddress(byte[] ipaddress) {
 return ((ipaddress[0] & 0xff) == 0xfe
 && (ipaddress[1] & 0xc0) == 0x80);
 }

 /**
 * Utility routine to check if the InetAddress is a site local address.
 *
 * @return a {@code boolean} indicating if the InetAddress is a site local
 * address; or false if address is not a site local unicast address.
 */
 @Override
 public boolean isSiteLocalAddress() {
 return holder6.isSiteLocalAddress();
 }

 /* static version of above */
 static boolean isSiteLocalAddress(byte[] ipaddress) {
 return ((ipaddress[0] & 0xff) == 0xfe
 && (ipaddress[1] & 0xc0) == 0xc0);
 }

 /**
 * Utility routine to check if the multicast address has global scope.
 *
 * @return a {@code boolean} indicating if the address has is a multicast
 * address of global scope, false if it is not of global scope or
 * it is not a multicast address
 */
 @Override
 public boolean isMCGlobal() {
 return holder6.isMCGlobal();
 }

 /**
 * Utility routine to check if the multicast address has node scope.
 *
 * @return a {@code boolean} indicating if the address has is a multicast
 * address of node-local scope, false if it is not of node-local
 * scope or it is not a multicast address
 */
 @Override
 public boolean isMCNodeLocal() {
 return holder6.isMCNodeLocal();
 }

 /**
 * Utility routine to check if the multicast address has link scope.
 *
 * @return a {@code boolean} indicating if the address has is a multicast
 * address of link-local scope, false if it is not of link-local
 * scope or it is not a multicast address
 */
 @Override
 public boolean isMCLinkLocal() {
 return holder6.isMCLinkLocal();
 }

 /**
 * Utility routine to check if the multicast address has site scope.
 *
 * @return a {@code boolean} indicating if the address has is a multicast
 * address of site-local scope, false if it is not of site-local
 * scope or it is not a multicast address
 */
 @Override
 public boolean isMCSiteLocal() {
 return holder6.isMCSiteLocal();
 }

 /**
 * Utility routine to check if the multicast address has organization scope.
 *
 * @return a {@code boolean} indicating if the address has is a multicast
 * address of organization-local scope, false if it is not of
 * organization-local scope or it is not a multicast address
 */
 @Override
 public boolean isMCOrgLocal() {
 return holder6.isMCOrgLocal();
 }
 /**
 * Returns the raw IP address of this {@code InetAddress} object. The result
 * is in network byte order: the highest order byte of the address is in
 * {@code getAddress()[0]}.
 *
 * @return the raw IP address of this object.
 */
 @Override
 public byte[] getAddress() {
 return holder6.ipaddress.clone();
 }

 /**
 * Returns the numeric scopeId, if this instance is associated with
 * an interface. If no scoped_id is set, the returned value is zero.
 *
 * @return the scopeId, or zero if not set.
 *
 * @since 1.5
 */
 public int getScopeId() {
 return holder6.scope_id;
 }

 /**
 * Returns the scoped interface, if this instance was created with
 * with a scoped interface.
 *
 * @return the scoped interface, or null if not set.
 * @since 1.5
 */
 public NetworkInterface getScopedInterface() {
 return holder6.scope_ifname;
 }

 /**
 * Returns the IP address string in textual presentation. If the instance
 * was created specifying a scope identifier then the scope id is appended
 * to the IP address preceded by a "%" (per-cent) character. This can be
 * either a numeric value or a string, depending on which was used to create
 * the instance.
 *
 * @return the raw IP address in a string format.
 */
 @Override
 public String getHostAddress() {
 return holder6.getHostAddress();
 }

 /**
 * Returns a hashcode for this IP address.
 *
 * @return a hash code value for this IP address.
 */
 @Override
 public int hashCode() {
 return holder6.hashCode();
 }

 /**
 * Compares this object against the specified object. The result is {@code
 * true} if and only if the argument is not {@code null} and it represents
 * the same IP address as this object.
 *
 * <p> Two instances of {@code InetAddress} represent the same IP address
 * if the length of the byte arrays returned by {@code getAddress} is the
 * same for both, and each of the array components is the same for the byte
 * arrays.
 *
 * @param obj the object to compare against.
 *
 * @return {@code true} if the objects are the same; {@code false} otherwise.
 *
 * @see java.net.InetAddress#getAddress()
 */
 @Override
 public boolean equals(Object obj) {
 if (obj == null || !(obj instanceof Inet6Address))
 return false;

 Inet6Address inetAddr = (Inet6Address)obj;

 return holder6.equals(inetAddr.holder6);
 }

 /**
 * Utility routine to check if the InetAddress is an
 * IPv4 compatible IPv6 address.
 *
 * @return a {@code boolean} indicating if the InetAddress is an IPv4
 * compatible IPv6 address; or false if address is IPv4 address.
 */
 public boolean isIPv4CompatibleAddress() {
 return holder6.isIPv4CompatibleAddress();
 }

 // Utilities

 private static final int INT16SZ = 2;

 /**
 * Convert IPv6 binary address into presentation (printable) format.
 *
 * @param src a byte array representing the IPv6 numeric address
 * @return a String representing an IPv6 address in
 * textual representation format
 */
 static String numericToTextFormat(byte[] src) {
 StringBuilder sb = new StringBuilder(39);
 for (int i = 0; i < (INADDRSZ / INT16SZ); i++) {
 sb.append(Integer.toHexString(((src[i<<1]<<8) & 0xff00)
 | (src[(i<<1)+1] & 0xff)));
 if (i < (INADDRSZ / INT16SZ) -1 ) {
 sb.append(":");
 }
 }
 return sb.toString();
 }

 /**
 * Perform class load-time initializations.
 */
 private static native void init();
}