Package it.unimi.dsi.sux4j.mph

Class ZFastTrieDistributorMonotoneMinimalPerfectHashFunction<T>

java.lang.Object

it.unimi.dsi.fastutil.objects.AbstractObject2LongFunction<K>

it.unimi.dsi.sux4j.mph.AbstractHashFunction<T>

it.unimi.dsi.sux4j.mph.ZFastTrieDistributorMonotoneMinimalPerfectHashFunction<T>

All Implemented Interfaces:

Function<T,Long>, Object2LongFunction<T>, Size64, Serializable, Function<T,Long>, ToLongFunction<T>

public class ZFastTrieDistributorMonotoneMinimalPerfectHashFunction<T>
extends AbstractHashFunction<T>
implements Serializable

A monotone minimal perfect hash implementation based on fixed-size bucketing that uses a z-fast trie as a distributor.

See the package overview for a comparison with other implementations. Similarly to a GOV3Function, an instance of this class may be signed.

See Also:

• Serialized Form

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	ZFastTrieDistributorMonotoneMinimalPerfectHashFunction.Builder<T>	A builder class for ZFastTrieDistributorMonotoneMinimalPerfectHashFunction.

Field Summary

Fields

Modifier and Type	Field	Description
static final long	serialVersionUID
protected final long	signatureMask	The mask to compare signatures, or zero for no signatures.
protected final LongBigList	signatures	The signatures.

Fields inherited from class it.unimi.dsi.fastutil.objects.AbstractObject2LongFunction

defRetValue

Constructor Summary

Constructors

Modifier	Constructor	Description
protected	ZFastTrieDistributorMonotoneMinimalPerfectHashFunction(Iterable<? extends T> keys, TransformationStrategy<? super T> transform, int log2BucketSize, int signatureWidth, File tempDir)	Creates a new monotone minimal perfect hash function based on a z-fast trie distributor using the given keys, transformation strategy and bucket size.

Method Summary

Modifier and Type	Method	Description
long	getLong(Object o)
static void	main(String[] arg)
long	numBits()
long	size64()

Methods inherited from class it.unimi.dsi.sux4j.mph.AbstractHashFunction

containsKey, size

Methods inherited from class it.unimi.dsi.fastutil.objects.AbstractObject2LongFunction

defaultReturnValue, defaultReturnValue

Methods inherited from class java.lang.Object

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

Methods inherited from interface it.unimi.dsi.fastutil.Function

apply, clear

Methods inherited from interface java.util.function.Function

compose

Methods inherited from interface it.unimi.dsi.fastutil.objects.Object2LongFunction

andThen, andThenByte, andThenChar, andThenDouble, andThenFloat, andThenInt, andThenLong, andThenObject, andThenReference, andThenShort, applyAsLong, composeByte, composeChar, composeDouble, composeFloat, composeInt, composeLong, composeObject, composeReference, composeShort, get, getOrDefault, getOrDefault, put, put, remove, removeLong

Field Details

serialVersionUID

public static final long serialVersionUID

See Also:

• Constant Field Values

signatureMask

protected final long signatureMask

The mask to compare signatures, or zero for no signatures.

signatures

protected final LongBigList signatures

The signatures.

Constructor Details

ZFastTrieDistributorMonotoneMinimalPerfectHashFunction

protected ZFastTrieDistributorMonotoneMinimalPerfectHashFunction(Iterable<? extends T> keys,
 TransformationStrategy<? super T> transform,
 int log2BucketSize,
 int signatureWidth,
 File tempDir)
                                                          throws IOException

Creates a new monotone minimal perfect hash function based on a z-fast trie distributor using the given keys, transformation strategy and bucket size.

Parameters:

keys - the keys among which the trie must be able to rank.

transform - a transformation strategy that must turn the keys into a list of distinct, prefix-free, lexicographically increasing (in iteration order) bit vectors.

log2BucketSize - the logarithm of the bucket size, or -1 for the default value.

signatureWidth - a signature width, or 0 for no signature.

tempDir - a temporary directory for the store files, or null for the standard temporary directory.

Throws:

IOException

Method Details

getLong

public long getLong(Object o)

Specified by:

getLong in interface Object2LongFunction<T>

size64

public long size64()

Specified by:

size64 in interface Size64

Overrides:

size64 in class AbstractHashFunction<T>

numBits

public long numBits()

main

public static void main(String[] arg)
                 throws NoSuchMethodException,
IOException,
JSAPException

Throws:

NoSuchMethodException

IOException

JSAPException