Inet6Address

public final class Inet6Address
extends InetAddress

This class represents an Internet Protocol version 6 (IPv6) address. Defined by RFC 2373: IP Version 6 Addressing Architecture.

Textual representation of IP addresses

1. The preferred form 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,

   1080:0:0:0:8:800:200C:417A

   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.

2. 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,

   1080::8:800:200C:417A

3. 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,

   ::FFFF:129.144.52.38
   ::129.144.52.38

   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:

   ::FFFF:d.d.d
   ::FFFF:d.d
   ::d.d.d
   ::d.d

   The following form:

   ::FFFF:d

   is valid, however it is an unconventional representation of the IPv4-compatible IPv6 address,

   ::255.255.0.d

   while "::d" corresponds to the general IPv6 address "0:0:0:0:0:0:0:d".

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.

Special IPv6 address

IPv4-mapped address

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. 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.

Textual representation of IPv6 scoped addresses

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].

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 scope_id) to an IPv6 address.

The general format for specifying the scope_id is the following:

IPv6-address%scope_id

The IPv6-address is a literal IPv6 address as described above. The scope_id refers to an interface on the local system, and it can be specified in two ways.

1. As a numeric identifier. 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.
2. As a string. This must be the exact string that is returned by 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.

Note also, that the numeric scope_id 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.

Summary

Inherited methods
From class java.net.InetAddress boolean equals(Object obj) Compares this object against the specified object. byte[] getAddress() Returns the raw IP address of this InetAddress object. static InetAddress[] getAllByName(String host) Given the name of a host, returns an array of its IP addresses, based on the configured name service on the system. static InetAddress getByAddress(byte[] addr) Returns an InetAddress object given the raw IP address . static InetAddress getByAddress(String host, byte[] addr) Creates an InetAddress based on the provided host name and IP address. static InetAddress getByName(String host) Determines the IP address of a host, given the host's name. String getCanonicalHostName() Gets the fully qualified domain name for this IP address. String getHostAddress() Returns the IP address string in textual presentation. String getHostName() Gets the host name for this IP address. static InetAddress getLocalHost() Returns the address of the local host. static InetAddress getLoopbackAddress() Returns the loopback address. int hashCode() Returns a hashcode for this IP address. boolean isAnyLocalAddress() Utility routine to check if the InetAddress in a wildcard address. boolean isLinkLocalAddress() Utility routine to check if the InetAddress is an link local address. boolean isLoopbackAddress() Utility routine to check if the InetAddress is a loopback address. boolean isMCGlobal() Utility routine to check if the multicast address has global scope. boolean isMCLinkLocal() Utility routine to check if the multicast address has link scope. boolean isMCNodeLocal() Utility routine to check if the multicast address has node scope. boolean isMCOrgLocal() Utility routine to check if the multicast address has organization scope. boolean isMCSiteLocal() Utility routine to check if the multicast address has site scope. boolean isMulticastAddress() Utility routine to check if the InetAddress is an IP multicast address. boolean isReachable(int timeout) Test whether that address is reachable. boolean isReachable(NetworkInterface netif, int ttl, int timeout) Test whether that address is reachable. boolean isSiteLocalAddress() Utility routine to check if the InetAddress is a site local address. String toString() Converts this IP address to a String.
From class java.lang.Object Object clone() Creates and returns a copy of this object. boolean equals(Object obj) Indicates whether some other object is "equal to" this one. void finalize() Called by the garbage collector on an object when garbage collection determines that there are no more references to the object. final Class<?> getClass() Returns the runtime class of this Object. int hashCode() Returns a hash code value for the object. final void notify() Wakes up a single thread that is waiting on this object's monitor. final void notifyAll() Wakes up all threads that are waiting on this object's monitor. String toString() Returns a string representation of the object. final void wait(long millis, int nanos) Causes the current thread to wait until another thread invokes the notify() method or the notifyAll() method for this object, or some other thread interrupts the current thread, or a certain amount of real time has elapsed. final void wait(long millis) Causes the current thread to wait until either another thread invokes the notify() method or the notifyAll() method for this object, or a specified amount of time has elapsed. final void wait() Causes the current thread to wait until another thread invokes the notify() method or the notifyAll() method for this object.

Public methods

boolean equals (Object obj)

byte[] getAddress ()

Inet6Address getByAddress (String host, 
                byte[] addr, 
                int scope_id)

Inet6Address getByAddress (String host, 
                byte[] addr, 
                NetworkInterface nif)

String getHostAddress ()

int getScopeId ()

NetworkInterface getScopedInterface ()

int hashCode ()

boolean isAnyLocalAddress ()

boolean isIPv4CompatibleAddress ()

boolean isLinkLocalAddress ()

boolean isLoopbackAddress ()

boolean isMCGlobal ()

boolean isMCLinkLocal ()

boolean isMCNodeLocal ()

boolean isMCOrgLocal ()

boolean isMCSiteLocal ()

boolean isMulticastAddress ()

boolean isSiteLocalAddress ()