com.peterphi.std.net

Class IpHelper

java.lang.Object

com.peterphi.std.net.IpHelper

public class IpHelper
extends Object

Field Summary

Fields

Modifier and Type	Field and Description
static Inet4Address	BROADCAST_ADDRESS The IPv4 broadcast address: 255.255.255.255
static Inet6Address	IPV6_ZERO The IPv6 equivalent of the "Quad Zero" IPv4 address (0.0.0.0).
static Inet4Address	QUAD_ZERO The "Quad Zero" IPv4 address: 0.0.0.0

Method Summary

Modifier and Type	Method and Description
static int	aton(byte[] addr) Converts an InetAddress' byte[] representation to a numeric address This only works for IPv4 (obviously)
static int	aton(Inet4Address ip) Converts an InetAddress to a numeric address
static int	aton(InetAddress ip) Converts an InetAddress to a numeric address only in the case of IPv4 (Inet4Address) addresses.
static int	aton(String ip) An equivalent of the C inet_aton function
static NetworkInterface	getInterfaceForLocalIp(InetAddress addr) Given a local IP address, returns the Interface it corresponds to
static String	getLocalhost() Gets the hostname of localhost
static String	getLocalIp() Gets the local IP address
static InetAddress	getLocalIpAddress() Returns the primary InetAddress of localhost
static InetAddress	getLocalIpAddress(String iface) Returns the IP address associated with iface
static List<InetAddress>	getLocalIpAddresses() Returns a list of local InetAddresses for this machine
static List<InetAddress>	getLocalIpAddresses(boolean pruneSiteLocal) Returns a list of local InetAddresses for this machine
static List<InetAddress>	getLocalIpAddresses(boolean pruneSiteLocal, boolean pruneDown) Returns a list of local InetAddresses for this machine
static List<InetAddress>	getLocalIpAddresses(String ifaceName, boolean pruneSiteLocal)
static String	getMacFor(NetworkInterface iface) Given a network interface, determines its mac address
static String	getMacForLocalIp(InetAddress addr) Given an InetAddress, determines the MAC Address (hardware address) of the corresponding interface
static boolean	isLocalAddress(InetAddress addr) Determines if a specified host or IP refers to the local machine
static boolean	isLocalAddress(String addr) Determines if a specified host or IP refers to the local machine
static boolean	isPublicallyRoutable(InetAddress addrIP) Deprecated. use isPubliclyRoutable(java.net.InetAddress)
static boolean	isPubliclyRoutable(InetAddress addrIP) Determines whether a particular IP address is publicly routable on the internet
static boolean	isValidCiscoWildcard(InetAddress wildcard) Determines if a specified address is a valid Cisco Wildcard (cisco's representation of a netmask)
static boolean	isValidNetmask(byte[] segments) Validates a netmask
static boolean	isValidNetmask(InetAddress netmask) Validates a netmask
static boolean	isValidNetmask(String netmask) Validates a netmask
static int	netmaskToPrefix(InetAddress netmask) Determines the prefix for a given netmask (ie.
static InetAddress	ntoa(byte[] addr)
static InetAddress	ntoa(int address) Converts numeric address to an InetAddress
static InetAddress	parse(String ip) Parses an IP address, throwing an IllegalArgumentException (rather than an UnknownHostException) if it is invalid
static String	physicalAddressToString(byte[] addr)
static int	prefixToMask(int prefix) Turns an IPv4 prefix into a numeric mask (the equivalent of running IpHelper.aton(prefixToNetmask(prefix)) but significantly faster)
static InetAddress	prefixToNetmask(int prefix) Turns an IPv4 prefix into a netmask
static InetAddress	stoa(String ip) Parses an IP address, returning it as an InetAddress This method exists to prevent code which is handling valid IP addresses from having to catch UnknownHostException excessively (when there is often no choice but to totally fail out anyway)

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

QUAD_ZERO

public static final Inet4Address QUAD_ZERO

The "Quad Zero" IPv4 address: 0.0.0.0

BROADCAST_ADDRESS

public static final Inet4Address BROADCAST_ADDRESS

The IPv4 broadcast address: 255.255.255.255

IPV6_ZERO

public static final Inet6Address IPV6_ZERO

The IPv6 equivalent of the "Quad Zero" IPv4 address (0.0.0.0). This is the Inet6Address ::

Method Detail

getLocalhost

public static String getLocalhost()
                           throws RuntimeException

Gets the hostname of localhost

Returns:

String

Throws:

RuntimeException - When we cannot determine the local machine's hostname

getLocalIp

public static String getLocalIp()
                         throws RuntimeException

Gets the local IP address

Returns:

String the local ip address's HostAddress

Throws:

RuntimeException - On error (eg. when the local host cannot be determined)

getLocalIpAddress

public static InetAddress getLocalIpAddress()
                                     throws RuntimeException

Returns the primary InetAddress of localhost

Returns:

InetAddress The InetAddress of the local host

Throws:

RuntimeException - On any error

Since:

1.0

getLocalIpAddress

public static InetAddress getLocalIpAddress(String iface)
                                     throws RuntimeException

Returns the IP address associated with iface

Parameters:

iface - The interface name

Returns:

InetAddress The InetAddress of the interface (or null if none found)

Throws:

RuntimeException - On any error

Since:

1.0

getLocalIpAddresses

public static List<InetAddress> getLocalIpAddresses()
                                             throws RuntimeException

Returns a list of local InetAddresses for this machine

Returns:

List[InetAddress] The list of IP addresses

Throws:

RuntimeException - If there is an error retrieving the InetAddresses

Since:

1.2

getLocalIpAddresses

public static List<InetAddress> getLocalIpAddresses(boolean pruneSiteLocal)
                                             throws RuntimeException

Returns a list of local InetAddresses for this machine

Parameters:

pruneSiteLocal - boolean Set to true if site local (10/8, for example) addresses should be pruned

Returns:

List[InetAddress] The list of addresses

Throws:

RuntimeException - If there is an error retrieving the InetAddresses

Since:

IpHelper.java 1.2

getLocalIpAddresses

public static List<InetAddress> getLocalIpAddresses(boolean pruneSiteLocal,
                                                    boolean pruneDown)
                                             throws RuntimeException

Returns a list of local InetAddresses for this machine

Parameters:

pruneSiteLocal - boolean Set to true if site local (10/8, for example) addresses should be pruned

pruneDown - boolean Set to true to prune out interfaces whose .isUp() return false

Returns:

List[InetAddress] The list of addresses

Throws:

RuntimeException - If there is an error retrieving the InetAddresses

Since:

IpHelper.java 2007-11-22

getMacForLocalIp

public static String getMacForLocalIp(InetAddress addr)
                               throws SocketException,
                                      NoMacAddressException,
                                      NoInterfaceException

Given an InetAddress, determines the MAC Address (hardware address) of the corresponding interface

Parameters:

addr - The IP address

Returns:

The MAC Address

Throws:

SocketException - If we couldn't get the interface

NoMacAddressException - If the interface doesn't have a mac address specified

NoInterfaceException

getMacFor

public static String getMacFor(NetworkInterface iface)
                        throws SocketException,
                               NoMacAddressException

Given a network interface, determines its mac address

Parameters:

iface - the interface

Returns:

The MAC address formatted in lower-case colon-delimited hexidecimal bytes (aa:ab:ac)

Throws:

SocketException

NoMacAddressException - If the interface doesn't have a mac address

getInterfaceForLocalIp

public static NetworkInterface getInterfaceForLocalIp(InetAddress addr)
                                               throws SocketException,
                                                      NoInterfaceException

Given a local IP address, returns the Interface it corresponds to

Parameters:

addr - The address

Returns:

The interface, or null if no interface corresponds to that address

Throws:

SocketException

NoInterfaceException - If there's no corresponding interface for the given IP

physicalAddressToString

public static String physicalAddressToString(byte[] addr)

getLocalIpAddresses

public static List<InetAddress> getLocalIpAddresses(String ifaceName,
                                                    boolean pruneSiteLocal)
                                             throws RuntimeException

Throws:

RuntimeException

isValidNetmask

public static boolean isValidNetmask(String netmask)

Validates a netmask

Parameters:

netmask - String A netmask to test

Returns:

boolean True if it validates, otherwise false

isValidNetmask

public static boolean isValidNetmask(InetAddress netmask)

Validates a netmask

Parameters:

netmask - InetAddress A netmask to test

Returns:

boolean True if it validates, otherwise false

isValidNetmask

public static boolean isValidNetmask(byte[] segments)

Validates a netmask

Parameters:

segments - byte[] A signed byte array whose binary values represent the address

Returns:

boolean True if valid, otherwise false

netmaskToPrefix

public static int netmaskToPrefix(InetAddress netmask)

Determines the prefix for a given netmask (ie. turns 255.255.255.0 into 24)
Returns the number of contiguous 1 bits. Throws an IllegalArgumentException if the address is an invalid netmask

Parameters:

netmask - An IP netmask (eg. 255.255.252.0)

Returns:

A prefix length (the number of 1-bits in the netmask)

Throws:

IllegalArgumentException - if an invalid netmask is passed

prefixToNetmask

public static InetAddress prefixToNetmask(int prefix)

Turns an IPv4 prefix into a netmask

Parameters:

prefix -

Returns:

prefixToMask

public static int prefixToMask(int prefix)

Turns an IPv4 prefix into a numeric mask (the equivalent of running IpHelper.aton(prefixToNetmask(prefix)) but significantly faster)

Parameters:

prefix -

Returns:

isValidCiscoWildcard

public static boolean isValidCiscoWildcard(InetAddress wildcard)

Determines if a specified address is a valid Cisco Wildcard (cisco's representation of a netmask)

Parameters:

wildcard - InetAddress

Returns:

boolean

isLocalAddress

public static boolean isLocalAddress(String addr)

Determines if a specified host or IP refers to the local machine

Parameters:

addr - String The host/IP

Returns:

boolean True if the input points to the local machine, otherwise false

isLocalAddress

public static boolean isLocalAddress(InetAddress addr)

Determines if a specified host or IP refers to the local machine

Parameters:

addr - String The host/IP

Returns:

boolean True if the input points to the local machine, otherwise false Checks by enumerating the NetworkInterfaces available to Java.

stoa

public static InetAddress stoa(String ip)

Parses an IP address, returning it as an InetAddress
This method exists to prevent code which is handling valid IP addresses from having to catch UnknownHostException excessively (when there is often no choice but to totally fail out anyway)

Parameters:

ip - a valid IP address (IPv4 or IPv6)

Returns:

the resulting InetAddress for that ip; this is equivalent to calling InetAddress.getByName on the IP (but without having to catch UnknownHostException)

Throws:

IllegalArgumentException - if the IP address is invalid (eg. null, an empty string or otherwise not in the valid IP address format)

aton

public static int aton(String ip)

An equivalent of the C inet_aton function

Parameters:

ip -

Returns:

aton

public static int aton(InetAddress ip)

Converts an InetAddress to a numeric address only in the case of IPv4 (Inet4Address) addresses. Other addresses will result in an Error being thrown

Parameters:

ip -

Returns:

aton

public static int aton(Inet4Address ip)

Converts an InetAddress to a numeric address

Parameters:

ip -

Returns:

aton

public static int aton(byte[] addr)

Converts an InetAddress' byte[] representation to a numeric address
This only works for IPv4 (obviously)

Parameters:

addr -

Returns:

ntoa

public static InetAddress ntoa(byte[] addr)

ntoa

public static InetAddress ntoa(int address)

Converts numeric address to an InetAddress

Parameters:

address -

Returns:

parse

public static InetAddress parse(String ip)

Parses an IP address, throwing an IllegalArgumentException (rather than an UnknownHostException) if it is invalid

Parameters:

ip - the IP - must not be null or an empty string. should be a valid IP address (eg. 1.2.3.4)

Returns:

an InetAddress

isPublicallyRoutable

@Deprecated
public static boolean isPublicallyRoutable(InetAddress addrIP)

Deprecated. use isPubliclyRoutable(java.net.InetAddress)

Determines whether a particular IP address is publicly routable on the internet

Parameters:

addrIP -

Returns:

isPubliclyRoutable

public static boolean isPubliclyRoutable(InetAddress addrIP)

Determines whether a particular IP address is publicly routable on the internet

Parameters:

addrIP -

Returns: