org.apache.commons.rng.core

Class BaseProvider

java.lang.Object

org.apache.commons.rng.core.BaseProvider

All Implemented Interfaces:

RestorableUniformRandomProvider, UniformRandomProvider

Direct Known Subclasses:

IntProvider, LongProvider

public abstract class BaseProvider
extends Object
implements RestorableUniformRandomProvider

Base class with default implementation for common methods.

Constructor Summary

Constructors

Constructor and Description
BaseProvider()

Method Summary

Modifier and Type	Method and Description
protected void	checkIndex(int min, int max, int index) Checks whether index is in the range [min, max].
protected void	checkStateSize(byte[] state, int expected) Checks that the state has the expected size.
protected void	fillState(int[] state, int[] seed) Simple filling procedure.
protected void	fillState(long[] state, long[] seed) Simple filling procedure.
protected byte[]	getStateInternal() Creates a snapshot of the RNG state.
int	nextInt(int n)
long	nextLong(long n)
void	restoreState(RandomProviderState state)
RandomProviderState	saveState()
protected void	setStateInternal(byte[] state) Resets the RNG to the given state.
String	toString()

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.apache.commons.rng.UniformRandomProvider

nextBoolean, nextBytes, nextBytes, nextDouble, nextFloat, nextInt, nextLong

Constructor Detail

BaseProvider

public BaseProvider()

Method Detail

nextInt

public int nextInt(int n)

Specified by:

nextInt in interface UniformRandomProvider

nextLong

public long nextLong(long n)

Specified by:

nextLong in interface UniformRandomProvider

saveState

public RandomProviderState saveState()

Specified by:

saveState in interface RestorableUniformRandomProvider

restoreState

public void restoreState(RandomProviderState state)

Specified by:

restoreState in interface RestorableUniformRandomProvider

toString

public String toString()

Overrides:

toString in class Object

getStateInternal

protected byte[] getStateInternal()

Creates a snapshot of the RNG state.

Returns:

the internal state.

Throws:

UnsupportedOperationException - if not implemented.

setStateInternal

protected void setStateInternal(byte[] state)

Resets the RNG to the given state.

Parameters:

state - State (previously obtained by a call to getStateInternal()).

Throws:

UnsupportedOperationException - if not implemented.

See Also:

checkStateSize(byte[],int)

fillState

protected void fillState(int[] state,
                         int[] seed)

Simple filling procedure. It will

1. fill the beginning of state by copying min(seed.length, state.length) elements from seed,
2. set all remaining elements of state with non-zero values (even if seed.length < state.length).

Parameters:

state - State. Must be allocated.

seed - Seed. Cannot be null.

fillState

protected void fillState(long[] state,
                         long[] seed)

Simple filling procedure. It will

1. fill the beginning of state by copying min(seed.length, state.length) elements from seed,
2. set all remaining elements of state with non-zero values (even if seed.length < state.length).

Parameters:

state - State. Must be allocated.

seed - Seed. Cannot be null.

checkStateSize

protected void checkStateSize(byte[] state,
                              int expected)

Checks that the state has the expected size.

Parameters:

state - State.

expected - Expected length of state array.

Throws:

IllegalArgumentException - if state.length != expected.

checkIndex

protected void checkIndex(int min,
                          int max,
                          int index)

Checks whether index is in the range [min, max].

Parameters:

min - Lower bound.

max - Upper bound.

index - Value that must lie within the [min, max] interval.

Throws:

IndexOutOfBoundsException - if index is not within the [min, max] interval.