com.eaio.uuid

Class UUIDGen

java.lang.Object

com.eaio.uuid.UUIDGen

public final class UUIDGen
extends Object

This class contains methods to generate UUID fields. These methods have been refactored out of UUID.

Starting with version 2, this implementation tries to obtain the MAC address of the network card. Under Microsoft Windows, the ifconfig command is used which may pop up a command window in Java Virtual Machines prior to 1.4 once this class is initialized. The command window is closed automatically.

The MAC address code has been tested extensively in Microsoft Windows, Linux, Solaris 8, HP-UX 11, but should work in MacOS X and BSDs, too.

If you use JDK 6 or later, the code in InterfaceAddress will be used.

Version:

$Id: UUIDGen.java 4714 2012-03-16 11:43:28Z johann $

Author:

Johann Burkard

See Also:

UUID, UUID

Constructor Summary

Constructors

Constructor and Description
UUIDGen()

Method Summary

Modifier and Type	Method and Description
static long	createTime(long currentTimeMillis) Creates a new time field from the given timestamp.
static long	getClockSeqAndNode() Returns the current clockSeqAndNode value.
static String	getMACAddress() Returns the MAC address.
static long	newTime() Generates a new time field.

Methods inherited from class java.lang.Object

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

Constructor Detail

UUIDGen

public UUIDGen()

Method Detail

getClockSeqAndNode

public static long getClockSeqAndNode()

Returns the current clockSeqAndNode value.

Returns:

the clockSeqAndNode value

See Also:

UUID.getClockSeqAndNode()

newTime

public static long newTime()

Generates a new time field. Each time field is unique and larger than the previously generated time field.

Returns:

a new time value

See Also:

UUID.getTime()

createTime

public static long createTime(long currentTimeMillis)

Creates a new time field from the given timestamp. Note that even identical values of currentTimeMillis will produce different time fields.

Parameters:

currentTimeMillis - the timestamp

Returns:

a new time value

See Also:

UUID.getTime()

getMACAddress

public static String getMACAddress()

Returns the MAC address. Not guaranteed to return anything.

Returns:

the MAC address, may be null