IpHelper (stdlib 10.0.0 API)

java.lang.Object
- com.peterphi.std.net.IpHelper

```
public class IpHelper
extends Object
```

Field Summary

Fields
Modifier and Type	Field	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

All Methods Static Methods Concrete Methods Deprecated Methods
Modifier and Type	Method	Description
`static int`	`aton(byte[] addr)`	Converts an InetAddress' byte[] representation to a numeric address This only works for IPv4 (obviously)
`static int`	`aton(String ip)`	An equivalent of the C `inet_aton` function
`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 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(String addr)`	Determines if a specified host or IP refers to the local machine
`static boolean`	`isLocalAddress(InetAddress 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(String netmask)`	Validates a netmask
`static boolean`	`isValidNetmask(InetAddress 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:

Class IpHelper

Field Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

QUAD_ZERO

BROADCAST_ADDRESS

IPV6_ZERO

Method Detail

getLocalhost

getLocalIp

getLocalIpAddress

getLocalIpAddress

getLocalIpAddresses

getLocalIpAddresses

getLocalIpAddresses

getMacForLocalIp

getMacFor

getInterfaceForLocalIp

physicalAddressToString

getLocalIpAddresses

isValidNetmask

isValidNetmask

isValidNetmask

netmaskToPrefix

prefixToNetmask

prefixToMask

isValidCiscoWildcard

isLocalAddress

isLocalAddress

stoa

aton

aton

aton

aton

ntoa

ntoa

parse

isPublicallyRoutable

isPubliclyRoutable