org.apache.commons.id.uuid
Class VersionOneGenerator

java.lang.Object
  org.apache.commons.id.uuid.VersionOneGenerator

All Implemented Interfaces:

IdentifierGenerator, Constants

public final class VersionOneGenerator
extends java.lang.Object
implements IdentifierGenerator, Constants

Class is responsible for generating version 1 UUID's per RFC 4122. This class attempts to locate the machine's node identifier first by attempting to loading the properties file UUID.properties from the system classpath. If the UUID.properties file does not exist then the generator will create a node identifier from random information as defined in the RFC 4122: A Universally Unique IDentifier (UUID) URN Namespace.

Version:

$Revision: 480488 $ $Date: 2006-11-29 08:57:26 +0000 (Wed, 29 Nov 2006) $

Author:

Commons-Id team

Field Summary

Fields inherited from interface org.apache.commons.id.uuid.Constants

CLOCK_SEQ_HI_AND_RESERVED_BYTE_8, FORMAT_POSITION1, FORMAT_POSITION2, FORMAT_POSITION3, FORMAT_POSITION4, MD5_ENCODING, SHA1_ENCODING, TIME_HI_AND_VERSION_BYTE_6, TIME_HI_BYTE_LEN, TIME_HI_START_POS, TIME_HI_TS_POS, TIME_LOW_BYTE_LEN, TIME_LOW_START_POS, TIME_LOW_TS_POS, TIME_MID_BYTE_LEN, TIME_MID_START_POS, TIME_MID_TS_POS, TOKEN_LENGTHS, TOKENS_IN_UUID, URN_PREFIX, UUID_BIT_LENGTH, UUID_BYTE_LENGTH, UUID_FORMATTED_LENGTH, UUID_UNFORMATTED_LENGTH, VARIANT_FUTURE, VARIANT_IETF_DRAFT, VARIANT_MS, VARIANT_NCS_COMPAT, VERSION_FIVE, VERSION_FOUR, VERSION_ONE, VERSION_THREE, VERSION_TWO, WRONG_VAR_VER_MSG

Method Summary

static VersionOneGenerator	getInstance() Returns the singleton instance of the version one UUID generator.
java.lang.Object	nextIdentifier() Gets the next identifier in the sequence.
UUID	nextUUID() Returns a new version 1 UUID.

Methods inherited from class java.lang.Object

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

Method Detail

getInstance

public static VersionOneGenerator getInstance()

Returns the singleton instance of the version one UUID generator.

Returns:

the singleton instance of the version one UUID generator.

nextIdentifier

public java.lang.Object nextIdentifier()

Description copied from interface: IdentifierGenerator

Gets the next identifier in the sequence.

Specified by:

nextIdentifier in interface IdentifierGenerator

Returns:

the next identifier in sequence

See Also:

IdentifierGenerator.nextIdentifier()

nextUUID

public UUID nextUUID()

Returns a new version 1 UUID. The method acts upons static variables and so should be sychronized.

Returns:

Returns a new version 1 UUID.