com.gigaspaces.internal.utils

Class BloomFilter

java.lang.Object

com.gigaspaces.internal.utils.BloomFilter

public class BloomFilter
extends Object

Method Summary

Modifier and Type	Method and Description
void	add(byte[] key)
void	add(String key)
static BloomFilter	alwaysMatchingBloomFilter()
void	clear()
static BloomFilter	getFilter(long numElements, double maxFalsePosProbability)
static BloomFilter	getFilter(long numElements, int targetBucketsPerElem)
int[]	getHashBuckets(byte[] key)
int[]	getHashBuckets(String key)
boolean	isPresent(byte[] key)
boolean	isPresent(String key)
String	toString()

Methods inherited from class java.lang.Object

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

Method Detail

getHashBuckets

public int[] getHashBuckets(String key)

getHashBuckets

public int[] getHashBuckets(byte[] key)

getFilter

public static BloomFilter getFilter(long numElements,
                                    int targetBucketsPerElem)

Returns:

A BloomFilter with the lowest practical false positive probability for the given number of elements.

getFilter

public static BloomFilter getFilter(long numElements,
                                    double maxFalsePosProbability)

Returns:

The smallest BloomFilter that can provide the given false positive probability rate for the given number of elements. Asserts that the given probability can be satisfied using this filter.

clear

public void clear()

isPresent

public boolean isPresent(String key)

isPresent

public boolean isPresent(byte[] key)

add

public void add(String key)

add

public void add(byte[] key)

toString

public String toString()

Overrides:

toString in class Object

alwaysMatchingBloomFilter

public static BloomFilter alwaysMatchingBloomFilter()

Returns:

a BloomFilter that always returns a positive match, for testing