org.apache.cassandra.utils
Class UUIDGen

java.lang.Object
  org.apache.cassandra.utils.UUIDGen

public class UUIDGen
extends java.lang.Object

The goods are here: www.ietf.org/rfc/rfc4122.txt.

Method Summary

static byte[]	decompose(java.util.UUID uuid) decomposes a uuid into raw bytes.
static long	getAdjustedTimestamp(java.util.UUID uuid) Returns a milliseconds-since-epoch value for a type-1 UUID.
static byte[]	getTimeUUIDBytes() Returns a 16 byte representation of a type 1 UUID (a time-based UUID), based on the current system time.
static byte[]	getTimeUUIDBytes(long timeMillis) Converts a milliseconds-since-epoch timestamp into the 16 byte representation of a type 1 UUID (a time-based UUID).
static java.util.UUID	getUUID(java.nio.ByteBuffer raw) creates a type 1 uuid from raw bytes.
static java.util.UUID	makeType1UUIDFromHost(java.net.InetAddress addr) Creates a type 1 UUID (time-based UUID) that substitutes a hash of an IP address in place of the MAC (unavailable to Java).

Methods inherited from class java.lang.Object

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

Method Detail

makeType1UUIDFromHost

public static java.util.UUID makeType1UUIDFromHost(java.net.InetAddress addr)

Creates a type 1 UUID (time-based UUID) that substitutes a hash of an IP address in place of the MAC (unavailable to Java).

Parameters:

addr - the host address to use

Returns:

a UUID instance

getUUID

public static java.util.UUID getUUID(java.nio.ByteBuffer raw)

creates a type 1 uuid from raw bytes.

decompose

public static byte[] decompose(java.util.UUID uuid)

decomposes a uuid into raw bytes.

getTimeUUIDBytes

public static byte[] getTimeUUIDBytes()

Returns a 16 byte representation of a type 1 UUID (a time-based UUID), based on the current system time.

Returns:

a type 1 UUID represented as a byte[]

getTimeUUIDBytes

public static byte[] getTimeUUIDBytes(long timeMillis)

Converts a milliseconds-since-epoch timestamp into the 16 byte representation of a type 1 UUID (a time-based UUID).

Warning: This method is not guaranteed to return unique UUIDs; Multiple invocations using identical timestamps will result in identical UUIDs.

Parameters:

timeMillis -

Returns:

a type 1 UUID represented as a byte[]

getAdjustedTimestamp

public static long getAdjustedTimestamp(java.util.UUID uuid)

Returns a milliseconds-since-epoch value for a type-1 UUID.

Parameters:

uuid - a type-1 (time-based) UUID

Returns:

the number of milliseconds since the unix epoch

Throws:

InvalidArgumentException - if the UUID is not version 1