com.hp.util.ip

Class MacPrefix

java.lang.Object

com.hp.util.cache.CacheableDataType

com.hp.util.ip.MacPrefix

All Implemented Interfaces:

Serializable, Comparable<MacPrefix>

public final class MacPrefix
extends CacheableDataType
implements Comparable<MacPrefix>

Represents a MAC address prefix; that is to say, the top N bytes of the address are fixed (where N is 1 to 5) and the remaining bytes are unspecified.

Instances of this class are created using the valueOf(byte[]) factory methods.

A string specification may be used to define the fixed bytes (with either colon or hyphen as the delimiter):

 {byte} [ : {byte} [ : ... ] ]    or    {byte} [ - {byte} [ - ... ] ]
 

where byte represents a hex value in the range 00 to FF.

For example, the specification "FE:00:45" declares a MAC prefix where the top 3 bytes are FE, 00, and 45, and the bottom three bytes may be any value.

Another example, the specification "FE-00-45-12-AB" declares a MAC prefix where the top 5 bytes are FE, 00, 45, 12, and AB, and the bottom byte may be any value.

Alternatively, a byte array may be used to specify the prefix. The byte arrays to produce the prefixes equivalent to the above examples are:

 final int B = 256; // makes it easier to read the declared byte arrays
 byte[] b1 = { 0xfe-B, 00, 0x45 };
 byte[] b2 = { 0xfe-B, 00, 0x45, 0x12, 0xab-B };
 

Author:

Simon Hunt

See Also:

Serialized Form

Method Summary

Modifier and Type	Method and Description
int	compareTo(MacPrefix o) Implements the Comparable interface, to return prefixes in natural order.
boolean	equals(Object o)
int	hashCode()
boolean	prefixes(MacAddress mac) Returns true if this MAC prefix applies to the specified MAC address.
int	size() Returns the number of bytes in this prefix.
String	toString()
static MacPrefix	valueOf(byte[] prefixBytes) Returns an object that represents the value of the MAC prefix defined by the specified MAC prefix bytes.
static MacPrefix	valueOf(String prefixStr) Returns an object that represents the value of the MAC prefix defined by the specified string.

Methods inherited from class com.hp.util.cache.CacheableDataType

getRefQ, keyFromBytes

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Method Detail

toString

public String toString()

Overrides:

toString in class Object

compareTo

public int compareTo(MacPrefix o)

Implements the Comparable interface, to return prefixes in natural order.

Specified by:

compareTo in interface Comparable<MacPrefix>

Parameters:

o - the other MAC prefix

Returns:

an integer value indicating the relative ordering

See Also:

Comparable.compareTo(T)

equals

public boolean equals(Object o)

Overrides:

equals in class Object

hashCode

public int hashCode()

Overrides:

hashCode in class Object

size

public int size()

Returns the number of bytes in this prefix.

Returns:

the number of bytes in the prefix

prefixes

public boolean prefixes(MacAddress mac)

Returns true if this MAC prefix applies to the specified MAC address.

Parameters:

mac - the address to examine

Returns:

true if this is a prefix of the given MAC address

valueOf

public static MacPrefix valueOf(byte[] prefixBytes)

Returns an object that represents the value of the MAC prefix defined by the specified MAC prefix bytes. Note that the bytes are presumed to be in network byte order; that is, the highest order byte of the prefix is at index 0. The array length is expected to be 1 to 5. An exception is thrown if it is not.

Parameters:

prefixBytes - the prefix bytes

Returns:

a MacPrefix instance

Throws:

NullPointerException - if prefixBytes is null

IllegalArgumentException - if prefixBytes is not an acceptable length

valueOf

public static MacPrefix valueOf(String prefixStr)

Returns an object that represents the value of the MAC prefix defined by the specified string. Both uppercase and lowercase hex digits are allowed. Acceptable input formats are:

• "XX"
• "XX:XX" or "XX-XX"
• "XX:XX:XX" or "XX-XX-XX"
• "XX:XX:XX:XX" or "XX-XX-XX-XX"
• "XX:XX:XX:XX:XX" or "XX-XX-XX-XX-XX"

where each "X" represents a hex digit

Parameters:

prefixStr - the string representation of the MAC prefix

Returns:

a MacPrefix instance

Throws:

NullPointerException - if prefixStr is null

IllegalArgumentException - if prefixStr is not an acceptable format