org.elasticsearch.search.suggest.phrase

Class DirectCandidateGeneratorBuilder

java.lang.Object

org.elasticsearch.search.suggest.phrase.DirectCandidateGeneratorBuilder

All Implemented Interfaces:

Writeable, ToXContent, PhraseSuggestionBuilder.CandidateGenerator

public final class DirectCandidateGeneratorBuilder
extends java.lang.Object
implements PhraseSuggestionBuilder.CandidateGenerator

Nested Class Summary

Nested classes/interfaces inherited from interface org.elasticsearch.common.io.stream.Writeable

Writeable.Reader<V>, Writeable.Writer<V>

Nested classes/interfaces inherited from interface org.elasticsearch.common.xcontent.ToXContent

ToXContent.DelegatingMapParams, ToXContent.MapParams, ToXContent.Params

Field Summary

Fields

Modifier and Type	Field and Description
static ParseField	ACCURACY_FIELD
static ParseField	DIRECT_GENERATOR_FIELD
static ParseField	FIELDNAME_FIELD
static ParseField	MAX_EDITS_FIELD
static ParseField	MAX_INSPECTIONS_FIELD
static ParseField	MAX_TERM_FREQ_FIELD
static ParseField	MIN_DOC_FREQ_FIELD
static ParseField	MIN_WORD_LENGTH_FIELD
static ParseField	POSTFILTER_FIELD
static ParseField	PREFILTER_FIELD
static ParseField	PREFIX_LENGTH_FIELD
static ParseField	SIZE_FIELD
static ParseField	SORT_FIELD
static ParseField	STRING_DISTANCE_FIELD
static ParseField	SUGGESTMODE_FIELD

Fields inherited from interface org.elasticsearch.common.xcontent.ToXContent

EMPTY_PARAMS

Constructor Summary

Constructors

Constructor and Description
DirectCandidateGeneratorBuilder(StreamInput in) Read from a stream.
DirectCandidateGeneratorBuilder(java.lang.String field)

Method Summary

Modifier and Type	Method and Description
DirectCandidateGeneratorBuilder	accuracy(float accuracy) Sets how similar the suggested terms at least need to be compared to the original suggest text tokens.
org.elasticsearch.search.suggest.phrase.PhraseSuggestionContext.DirectCandidateGenerator	build(MapperService mapperService)
boolean	equals(java.lang.Object obj)
static DirectCandidateGeneratorBuilder	fromXContent(XContentParser parser)
java.lang.String	getType() gets the type identifier of this CandidateGenerator
int	hashCode()
DirectCandidateGeneratorBuilder	maxEdits(java.lang.Integer maxEdits) Sets the maximum edit distance candidate suggestions can have in order to be considered as a suggestion.
DirectCandidateGeneratorBuilder	maxInspections(java.lang.Integer maxInspections) A factor that is used to multiply with the size in order to inspect more candidate suggestions.
DirectCandidateGeneratorBuilder	maxTermFreq(float maxTermFreq) Sets a maximum threshold in number of documents a suggest text token can exist in order to be corrected.
DirectCandidateGeneratorBuilder	minDocFreq(float minDocFreq) Sets a minimal threshold in number of documents a suggested term should appear in.
DirectCandidateGeneratorBuilder	minWordLength(int minWordLength) The minimum length a suggest text term must have in order to be corrected.
DirectCandidateGeneratorBuilder	postFilter(java.lang.String postFilter) Sets a filter (analyzer) that is applied to each of the generated tokens before they are passed to the actual phrase scorer.
DirectCandidateGeneratorBuilder	preFilter(java.lang.String preFilter) Sets a filter (analyzer) that is applied to each of the tokens passed to this candidate generator.
DirectCandidateGeneratorBuilder	prefixLength(int prefixLength) Sets the number of minimal prefix characters that must match in order be a candidate suggestion.
DirectCandidateGeneratorBuilder	size(int size) Sets the maximum suggestions to be returned per suggest text term.
DirectCandidateGeneratorBuilder	sort(java.lang.String sort) Sets how to sort the suggest terms per suggest text token.
DirectCandidateGeneratorBuilder	stringDistance(java.lang.String stringDistance) Sets what string distance implementation to use for comparing how similar suggested terms are.
DirectCandidateGeneratorBuilder	suggestMode(java.lang.String suggestMode) The global suggest mode controls what suggested terms are included or controls for what suggest text tokens, terms should be suggested for.
java.lang.String	toString()
XContentBuilder	toXContent(XContentBuilder builder, ToXContent.Params params)
void	writeTo(StreamOutput out) Write this into the StreamOutput.

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.elasticsearch.common.xcontent.ToXContent

isFragment

Field Detail

DIRECT_GENERATOR_FIELD

public static final ParseField DIRECT_GENERATOR_FIELD

FIELDNAME_FIELD

public static final ParseField FIELDNAME_FIELD

PREFILTER_FIELD

public static final ParseField PREFILTER_FIELD

POSTFILTER_FIELD

public static final ParseField POSTFILTER_FIELD

SUGGESTMODE_FIELD

public static final ParseField SUGGESTMODE_FIELD

MIN_DOC_FREQ_FIELD

public static final ParseField MIN_DOC_FREQ_FIELD

ACCURACY_FIELD

public static final ParseField ACCURACY_FIELD

SIZE_FIELD

public static final ParseField SIZE_FIELD

SORT_FIELD

public static final ParseField SORT_FIELD

STRING_DISTANCE_FIELD

public static final ParseField STRING_DISTANCE_FIELD

MAX_EDITS_FIELD

public static final ParseField MAX_EDITS_FIELD

MAX_INSPECTIONS_FIELD

public static final ParseField MAX_INSPECTIONS_FIELD

MAX_TERM_FREQ_FIELD

public static final ParseField MAX_TERM_FREQ_FIELD

PREFIX_LENGTH_FIELD

public static final ParseField PREFIX_LENGTH_FIELD

MIN_WORD_LENGTH_FIELD

public static final ParseField MIN_WORD_LENGTH_FIELD

Constructor Detail

DirectCandidateGeneratorBuilder

public DirectCandidateGeneratorBuilder(java.lang.String field)

Parameters:

field - Sets from what field to fetch the candidate suggestions from.

DirectCandidateGeneratorBuilder

public DirectCandidateGeneratorBuilder(StreamInput in)
                                throws java.io.IOException

Read from a stream.

Throws:

java.io.IOException

Method Detail

writeTo

public void writeTo(StreamOutput out)
             throws java.io.IOException

Description copied from interface: Writeable

Write this into the StreamOutput.

Specified by:

writeTo in interface Writeable

Throws:

java.io.IOException

suggestMode

public DirectCandidateGeneratorBuilder suggestMode(java.lang.String suggestMode)

The global suggest mode controls what suggested terms are included or controls for what suggest text tokens, terms should be suggested for. Three possible values can be specified:

1. missing - Only suggest terms in the suggest text that aren't in the index. This is the default.
2. popular - Only suggest terms that occur in more docs then the original suggest text term.
3. always - Suggest any matching suggest terms based on tokens in the suggest text.

accuracy

public DirectCandidateGeneratorBuilder accuracy(float accuracy)

Sets how similar the suggested terms at least need to be compared to the original suggest text tokens. A value between 0 and 1 can be specified. This value will be compared to the string distance result of each candidate spelling correction.

Default is 0.5

size

public DirectCandidateGeneratorBuilder size(int size)

Sets the maximum suggestions to be returned per suggest text term.

sort

public DirectCandidateGeneratorBuilder sort(java.lang.String sort)

Sets how to sort the suggest terms per suggest text token. Two possible values:

1. score - Sort should first be based on score, then document frequency and then the term itself.
2. frequency - Sort should first be based on document frequency, then score and then the term itself.

What the score is depends on the suggester being used.

stringDistance

public DirectCandidateGeneratorBuilder stringDistance(java.lang.String stringDistance)

Sets what string distance implementation to use for comparing how similar suggested terms are. Four possible values can be specified:

1. internal - This is the default and is based on damerau_levenshtein, but highly optimized for comparing string distance for terms inside the index.
2. damerau_levenshtein - String distance algorithm based on Damerau-Levenshtein algorithm.
3. levenstein - String distance algorithm based on Levenstein edit distance algorithm.
4. jarowinkler - String distance algorithm based on Jaro-Winkler algorithm.
5. ngram - String distance algorithm based on character n-grams.

maxEdits

public DirectCandidateGeneratorBuilder maxEdits(java.lang.Integer maxEdits)

Sets the maximum edit distance candidate suggestions can have in order to be considered as a suggestion. Can only be a value between 1 and 2. Any other value result in an bad request error being thrown. Defaults to 2.

maxInspections

public DirectCandidateGeneratorBuilder maxInspections(java.lang.Integer maxInspections)

A factor that is used to multiply with the size in order to inspect more candidate suggestions. Can improve accuracy at the cost of performance. Defaults to 5.

maxTermFreq

public DirectCandidateGeneratorBuilder maxTermFreq(float maxTermFreq)

Sets a maximum threshold in number of documents a suggest text token can exist in order to be corrected. Can be a relative percentage number (e.g 0.4) or an absolute number to represent document frequencies. If an value higher than 1 is specified then fractional can not be specified. Defaults to 0.01.

This can be used to exclude high frequency terms from being suggested. High frequency terms are usually spelled correctly on top of this this also improves the suggest performance.

prefixLength

public DirectCandidateGeneratorBuilder prefixLength(int prefixLength)

Sets the number of minimal prefix characters that must match in order be a candidate suggestion. Defaults to 1. Increasing this number improves suggest performance. Usually misspellings don't occur in the beginning of terms.

minWordLength

public DirectCandidateGeneratorBuilder minWordLength(int minWordLength)

The minimum length a suggest text term must have in order to be corrected. Defaults to 4.

minDocFreq

public DirectCandidateGeneratorBuilder minDocFreq(float minDocFreq)

Sets a minimal threshold in number of documents a suggested term should appear in. This can be specified as an absolute number or as a relative percentage of number of documents. This can improve quality by only suggesting high frequency terms. Defaults to 0f and is not enabled. If a value higher than 1 is specified then the number cannot be fractional.

preFilter

public DirectCandidateGeneratorBuilder preFilter(java.lang.String preFilter)

Sets a filter (analyzer) that is applied to each of the tokens passed to this candidate generator. This filter is applied to the original token before candidates are generated.

postFilter

public DirectCandidateGeneratorBuilder postFilter(java.lang.String postFilter)

Sets a filter (analyzer) that is applied to each of the generated tokens before they are passed to the actual phrase scorer.

getType

public java.lang.String getType()

gets the type identifier of this CandidateGenerator

Specified by:

getType in interface PhraseSuggestionBuilder.CandidateGenerator

toXContent

public XContentBuilder toXContent(XContentBuilder builder,
                                  ToXContent.Params params)
                           throws java.io.IOException

Specified by:

toXContent in interface ToXContent

Throws:

java.io.IOException

fromXContent

public static DirectCandidateGeneratorBuilder fromXContent(XContentParser parser)
                                                    throws java.io.IOException

Throws:

java.io.IOException

build

public org.elasticsearch.search.suggest.phrase.PhraseSuggestionContext.DirectCandidateGenerator build(MapperService mapperService)
                                                                                               throws java.io.IOException

Specified by:

build in interface PhraseSuggestionBuilder.CandidateGenerator

Throws:

java.io.IOException

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object

hashCode

public int hashCode()

Overrides:

hashCode in class java.lang.Object

equals

public boolean equals(java.lang.Object obj)

Overrides:

equals in class java.lang.Object