Package org.apache.lucene.codecs.bloom

Class DefaultBloomFilterFactory

java.lang.Object

org.apache.lucene.codecs.bloom.BloomFilterFactory

org.apache.lucene.codecs.bloom.DefaultBloomFilterFactory

public class DefaultBloomFilterFactory
extends BloomFilterFactory

Default policy is to allocate a bitset with 10% saturation given a unique term per document. Bits are set via MurmurHash2 hashing function.

WARNING: This API is experimental and might change in incompatible ways in the next release.

Constructor Summary

Constructors

Constructor	Description
DefaultBloomFilterFactory()

Method Summary

Modifier and Type	Method	Description
FuzzySet	getSetForField(SegmentWriteState state, FieldInfo info)
boolean	isSaturated(FuzzySet bloomFilter, FieldInfo fieldInfo)	Used to determine if the given filter has reached saturation and should be retired i.e.

Methods inherited from class org.apache.lucene.codecs.bloom.BloomFilterFactory

downsize

Methods inherited from class java.lang.Object

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

Constructor Detail

DefaultBloomFilterFactory

public DefaultBloomFilterFactory()

Method Detail

getSetForField

public FuzzySet getSetForField(SegmentWriteState state,
                               FieldInfo info)

Specified by:

getSetForField in class BloomFilterFactory

Parameters:

state - The content to be indexed

info - the field requiring a BloomFilter

Returns:

An appropriately sized set or null if no BloomFiltering required

isSaturated

public boolean isSaturated(FuzzySet bloomFilter,
                           FieldInfo fieldInfo)

Description copied from class: BloomFilterFactory

Used to determine if the given filter has reached saturation and should be retired i.e. not saved any more

Specified by:

isSaturated in class BloomFilterFactory

Parameters:

bloomFilter - The bloomFilter being tested

fieldInfo - The field with which this filter is associated

Returns:

true if the set has reached saturation and should be retired