Package com.fasterxml.uuid.impl

Class RandomBasedGenerator

java.lang.Object

com.fasterxml.uuid.UUIDGenerator

com.fasterxml.uuid.NoArgGenerator

com.fasterxml.uuid.impl.RandomBasedGenerator

public class RandomBasedGenerator
extends NoArgGenerator

Implementation of UUID generator that uses generation method 4.

Note on random number generation when using SecureRandom for random number generation: the first time SecureRandom object is used, there is noticeable delay between calling the method and getting the reply. This is because SecureRandom has to initialize itself to reasonably random state. Thus, if you want to lessen delay, it may be be a good idea to either get the first random UUID asynchronously from a separate thread, or to use the other generateRandomBasedUUID passing a previously initialized SecureRandom instance.

Since:

3.0

Field Summary

Fields

Modifier and Type	Field	Description
protected final Random	_random	Random number generator that this generator uses.
protected final boolean	_secureRandom	Looks like SecureRandom implementation is more efficient using single call access (compared to basic Random), so let's use that knowledge to our benefit.

Constructor Summary

Constructors

Constructor	Description
RandomBasedGenerator(Random rnd)

Method Summary

Modifier and Type	Method	Description
UUID	generate()	Method for generating a UUID.
UUIDType	getType()	Accessor for determining type of UUIDs (version) that this generator instance will produce.

Methods inherited from class com.fasterxml.uuid.UUIDGenerator

_toInt, _toLong, _toShort

Methods inherited from class java.lang.Object

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

Field Details

_random

protected final Random _random

Random number generator that this generator uses.

_secureRandom

protected final boolean _secureRandom

Looks like SecureRandom implementation is more efficient using single call access (compared to basic Random), so let's use that knowledge to our benefit.

Constructor Details

RandomBasedGenerator

public RandomBasedGenerator(Random rnd)

Parameters:

rnd - Random number generator to use for generating UUIDs; if null, shared default generator is used. Note that it is strongly recommend to use a good (pseudo) random number generator; for example, JDK's SecureRandom.

Method Details

getType

public UUIDType getType()

Description copied from class: UUIDGenerator

Accessor for determining type of UUIDs (version) that this generator instance will produce.

Specified by:

getType in class UUIDGenerator

generate

public UUID generate()

Description copied from class: NoArgGenerator

Method for generating a UUID.

Specified by:

generate in class NoArgGenerator

Returns:

Newly generated UUID