|
|||||||||
PREV CLASS NEXT CLASS | FRAMES NO FRAMES | ||||||||
SUMMARY: NESTED | FIELD | CONSTR | METHOD | DETAIL: FIELD | CONSTR | METHOD |
java.lang.Objectjava.util.UUID
public final class UUID
This class represents a 128-bit UUID value. There are several types of UUID, and while this class can be used to store them, only the Leach-Salz (variant 2) UUID specified in RFC-4122 will give meaningful results from the method calls. See: http://tools.ietf.org/html/4122 for the details The format of a Leach-Salz (variant 2) time-based (version 1) UUID is as follows: time_low - upper 32 bits of the most significant 64 bits, this is the least-significant part of the timestamp. time_mid - bits 16-31 of the most significant 64 bits, this is the middle portion of the timestamp. version - bits 8-15 of the most significant 64 bits. time_hi - bits 0-7 of the most significant 64 bits, the most significant portion of the timestamp. clock_and_reserved - bits 48-63 of the least significant 64 bits. a variable number of bits hold the variant (see the spec) node identifier - bits 0-47 of the least signficant 64 bits. These fields are valid only for version 1, in the remaining versions, only the version and variant fields are set, all others are used for data.
Constructor Summary | |
---|---|
UUID(long mostSigBits,
long leastSigBits)
Constructs a new UUID. |
Method Summary | |
---|---|
int |
clockSequence()
Returns the clock-sequence value of this UUID. |
int |
compareTo(UUID o)
Compare this UUID to another. |
boolean |
equals(Object obj)
Compare a (UUID) object to this one |
static UUID |
fromString(String name)
Creates a UUID object from a Sting representation. |
long |
getLeastSignificantBits()
Returns the least significant 64 bits of the UUID as a long . |
long |
getMostSignificantBits()
Returns the most significant 64 bits of the UUID as a long . |
int |
hashCode()
Returns a hash of this UUID. |
static UUID |
nameUUIDFromBytes(byte[] name)
Creates a UUID version 3 object (name based with MD5 hashing) from a series of bytes representing a name. |
long |
node()
Returns the 48-bit node value in a long. |
static UUID |
randomUUID()
Generate a Leach-Salz (Variant 2) randomly generated (version 4) UUID. |
long |
timestamp()
Returns the 60-bit timestamp value of the UUID in a long. |
String |
toString()
Returns a String representation of the UUID. |
int |
variant()
Returns the variant of the UUID This may be: 0 = Reserved for NCS backwards-compatibility 2 = Leach-Salz (supports the other methods in this class) 6 = Reserved for Microsoft backwards-compatibility 7 = (reserved for future use) |
int |
version()
Returns the version # of the UUID. |
Methods inherited from class java.lang.Object |
---|
clone, finalize, getClass, notify, notifyAll, wait, wait, wait |
Constructor Detail |
---|
public UUID(long mostSigBits, long leastSigBits)
Method Detail |
---|
public int clockSequence()
UnsupportedOperationException
- if the UUID type is not 1.public int compareTo(UUID o)
compareTo
in interface Comparable<UUID>
o
- the object to be compared
public boolean equals(Object obj)
equals
in class Object
obj
- the Object to compare to
Object.hashCode()
public static UUID fromString(String name)
toString()
public String toString()
toString
in class Object
Object.getClass()
,
Object.hashCode()
,
Class.getName()
,
Integer.toHexString(int)
public long getLeastSignificantBits()
long
.
public long getMostSignificantBits()
long
.
public int hashCode()
hashCode
in class Object
Object.equals(Object)
,
System.identityHashCode(Object)
public static UUID nameUUIDFromBytes(byte[] name)
public long node()
UnsupportedOperationException
- if the UUID type is not 1.public long timestamp()
UnsupportedOperationException
- if the UUID type is not 1.public static UUID randomUUID()
public int variant()
public int version()
|
|||||||||
PREV CLASS NEXT CLASS | FRAMES NO FRAMES | ||||||||
SUMMARY: NESTED | FIELD | CONSTR | METHOD | DETAIL: FIELD | CONSTR | METHOD |