Package util

Record Class Randomness

java.lang.Object

java.lang.Record

util.Randomness

Record Components:

seed - The seed of this source of randomness. Values derived from this source are deterministic for a given seed and ID.

public record Randomness(long seed)
extends Record

Provides random number generator seeds to support reproducible randomness that is robust to different compositions of submodels with unique string identifiers.

Field Summary

Fields

Modifier and Type	Field	Description
private final long	seed	The field for the seed record component.

Constructor Summary

Constructors

Constructor	Description
Randomness(long seed)	Creates an instance of a Randomness record class.

Method Summary

Modifier and Type	Method	Description
final boolean	equals(Object o)	Indicates whether some other object is "equal to" this one.
Random	generatorFor(String id)	Return a random number generator to be used by a submodel with ID `id`.
final int	hashCode()	Returns a hash code value for this object.
Randomness	next()	Return a new source of randomness that is next (after this one) in a deterministic sequence of randomness sources.
Randomness	randomnessFor(String id)	Return a new source of randomness to be used by a submodel with ID `id`.
long	seed()	Returns the value of the seed record component.
long	seedFor(String id)	Return an RNG seed to be used by a submodel with ID `id`.
final String	toString()	Returns a string representation of this record class.

Methods inherited from class java.lang.Object

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

Field Details

seed

private final long seed

The field for the seed record component.

Constructor Details

Randomness

public Randomness(long seed)

Creates an instance of a Randomness record class.

Parameters:

seed - the value for the seed record component

Method Details

next

public Randomness next()

Return a new source of randomness that is next (after this one) in a deterministic sequence of randomness sources. This should only be called once on a source, as returned values are identical. This is useful for programs that want to run a sequence of independent simulations that is reproducible from a single initial seed.

randomnessFor

public Randomness randomnessFor(String id)

Return a new source of randomness to be used by a submodel with ID `id`. This facilitates hierarchical submodels.

seedFor

public long seedFor(String id)

Return an RNG seed to be used by a submodel with ID `id`.

generatorFor

public Random generatorFor(String id)

Return a random number generator to be used by a submodel with ID `id`.

toString

public final String toString()

Returns a string representation of this record class. The representation contains the name of the class, followed by the name and value of each of the record components.

Specified by:

toString in class Record

Returns:

a string representation of this object

hashCode

public final int hashCode()

Returns a hash code value for this object. The value is derived from the hash code of each of the record components.

Specified by:

hashCode in class Record

Returns:

a hash code value for this object

equals

public final boolean equals(Object o)

Indicates whether some other object is "equal to" this one. The objects are equal if the other object is of the same class and if all the record components are equal. All components in this record class are compared with '=='.

Specified by:

equals in class Record

Parameters:

o - the object with which to compare

Returns:

true if this object is the same as the o argument; false otherwise.

seed

public long seed()

Returns the value of the seed record component.

Returns:

the value of the seed record component