org.jboss.util.id
Class UID

java.lang.Object
  org.jboss.util.id.UID

All Implemented Interfaces:

Serializable, Cloneable, ID

public class UID
extends Object
implements ID

A unique identifier (uniqueness only guarantied inside of the virtual machine in which it was created).

The identifier is composed of:

1. A long generated from the current system time (in milliseconds).
2. A long generated from a counter (which is the number of UID objects that have been created durring the life of the executing virtual machine).

    [ time ] - [ counter ]
 

Numbers are converted to radix(Character.MAX_RADIX) when converting to strings.

This should provide adequate uniqueness for most purposes.

Version:

$Revision: 1.4.6.4 $

Author:

Jason Dillon

See Also:

Serialized Form

Field Summary

protected static EDU.oswego.cs.dl.util.concurrent.SynchronizedLong	COUNTER A counter for generating identity values
protected long	id The identity portion of the UID
protected long	time The time portion of the UID

Constructor Summary

	UID() Construct a new UID.
protected	UID(UID uid) Copy a UID.

Method Summary

static String	asString() Returns a UID as a string.
Object	clone() Returns a copy of this UID.
boolean	equals(Object obj) Checks if the given object is equal to this UID.
long	getID() Get the identity portion of this UID.
long	getTime() Get the time portion of this UID.
int	hashCode() Return the hash code of this UID.
String	toString() Return a string representation of this UID.

Methods inherited from class java.lang.Object

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

Field Detail

COUNTER

protected static final EDU.oswego.cs.dl.util.concurrent.SynchronizedLong COUNTER

A counter for generating identity values

time

protected final long time

The time portion of the UID

id

protected final long id

The identity portion of the UID

Constructor Detail

UID

public UID()

Construct a new UID.

UID

protected UID(UID uid)

Copy a UID.

Method Detail

getTime

public final long getTime()

Get the time portion of this UID.

Returns:

The time portion of this UID.

getID

public final long getID()

Get the identity portion of this UID.

Returns:

The identity portion of this UID.

toString

public String toString()

Return a string representation of this UID.

Overrides:

toString in class Object

Returns:

A string representation of this UID.

hashCode

public int hashCode()

Return the hash code of this UID.

Overrides:

hashCode in class Object

Returns:

The hash code of this UID.

equals

public boolean equals(Object obj)

Checks if the given object is equal to this UID.

Overrides:

equals in class Object

Parameters:

obj - Object to test equality with.

Returns:

True if object is equal to this UID.

clone

public Object clone()

Returns a copy of this UID.

Overrides:

clone in class Object

Returns:

A copy of this UID.

asString

public static String asString()

Returns a UID as a string.

Returns:

UID as a string.