Class AnalyzingInfixSuggester

Analyzes the input text and then suggests matches based on prefix matches to any tokens in the indexed text. This also highlights the tokens that match.

This suggester supports payloads. Matches are sorted only by the suggest weight; it would be nice to support blended score + weight sort in the future. This means this suggester best applies when there is a strong a-priori ranking of all the suggestions.

This suggester supports contexts, however the contexts must be valid utf8 (arbitrary binary terms will not work).

Note

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

Inheritance

object

Lookup

AnalyzingInfixSuggester

BlendedInfixSuggester

Implements

IDisposable

Inherited Members

Lookup.CHARSEQUENCE_COMPARER

Lookup.Build(IDictionary)

Lookup.Load(Stream)

Lookup.Store(Stream)

Lookup.DoLookup(string, bool, int)

object.Equals(object)

object.Equals(object, object)

object.GetHashCode()

object.GetType()

object.MemberwiseClone()

object.ReferenceEquals(object, object)

object.ToString()

Namespace: Lucene.Net.Search.Suggest.Analyzing

Assembly: Lucene.Net.Suggest.dll

Syntax

public class AnalyzingInfixSuggester : Lookup, IDisposable

Constructors

AnalyzingInfixSuggester(IAnalyzingInfixSuggesterIndexWriterConfigFactory, LuceneVersion, Directory, Analyzer, Analyzer, int, bool)

Create a new instance, loading from a previously built AnalyzingInfixSuggester directory, if it exists. This directory must be private to the infix suggester (i.e., not an external Lucene index). Note that Dispose() will also dispose the provided directory.

Declaration

public AnalyzingInfixSuggester(IAnalyzingInfixSuggesterIndexWriterConfigFactory indexWriterConfigFactory, LuceneVersion matchVersion, Directory dir, Analyzer indexAnalyzer, Analyzer queryAnalyzer, int minPrefixChars, bool commitOnBuild)

Parameters

Type	Name	Description
IAnalyzingInfixSuggesterIndexWriterConfigFactory	indexWriterConfigFactory	Factory for creating the Lucene.Net.Index.IndexWriterConfig.
LuceneVersion	matchVersion
Directory	dir
Analyzer	indexAnalyzer
Analyzer	queryAnalyzer
int	minPrefixChars	Minimum number of leading characters before Lucene.Net.Search.PrefixQuery is used (default 4). Prefixes shorter than this are indexed as character ngrams (increasing index size but making lookups faster).
bool	commitOnBuild	Call commit after the index has finished building. This would persist the suggester index to disk and future instances of this suggester can use this pre-built dictionary.

AnalyzingInfixSuggester(LuceneVersion, Directory, Analyzer)

Create a new instance, loading from a previously built AnalyzingInfixSuggester directory, if it exists. This directory must be private to the infix suggester (i.e., not an external Lucene index). Note that Dispose() will also dispose the provided directory.

Declaration

public AnalyzingInfixSuggester(LuceneVersion matchVersion, Directory dir, Analyzer analyzer)

Parameters

Type	Name	Description
LuceneVersion	matchVersion
Directory	dir
Analyzer	analyzer

AnalyzingInfixSuggester(LuceneVersion, Directory, Analyzer, Analyzer, int)

Create a new instance, loading from a previously built AnalyzingInfixSuggester directory, if it exists. This directory must be private to the infix suggester (i.e., not an external Lucene index). Note that Dispose() will also dispose the provided directory.

Declaration

public AnalyzingInfixSuggester(LuceneVersion matchVersion, Directory dir, Analyzer indexAnalyzer, Analyzer queryAnalyzer, int minPrefixChars)

Parameters

Type	Name	Description
LuceneVersion	matchVersion
Directory	dir
Analyzer	indexAnalyzer
Analyzer	queryAnalyzer
int	minPrefixChars	Minimum number of leading characters before Lucene.Net.Search.PrefixQuery is used (default 4). Prefixes shorter than this are indexed as character ngrams (increasing index size but making lookups faster).

AnalyzingInfixSuggester(LuceneVersion, Directory, Analyzer, Analyzer, int, bool)

Create a new instance, loading from a previously built AnalyzingInfixSuggester directory, if it exists. This directory must be private to the infix suggester (i.e., not an external Lucene index). Note that Dispose() will also dispose the provided directory.

Declaration

public AnalyzingInfixSuggester(LuceneVersion matchVersion, Directory dir, Analyzer indexAnalyzer, Analyzer queryAnalyzer, int minPrefixChars, bool commitOnBuild)

Parameters

Type	Name	Description
LuceneVersion	matchVersion
Directory	dir
Analyzer	indexAnalyzer
Analyzer	queryAnalyzer
int	minPrefixChars	Minimum number of leading characters before Lucene.Net.Search.PrefixQuery is used (default 4). Prefixes shorter than this are indexed as character ngrams (increasing index size but making lookups faster).
bool	commitOnBuild	Call commit after the index has finished building. This would persist the suggester index to disk and future instances of this suggester can use this pre-built dictionary.

Fields

CONTEXTS_FIELD_NAME

Field name used for the indexed context, as a Lucene.Net.Documents.StringField and a Lucene.Net.Documents.SortedSetDocValuesField, for filtering.

Declaration

protected const string CONTEXTS_FIELD_NAME = "contexts"

Field Value

Type	Description
string

DEFAULT_MIN_PREFIX_CHARS

Default minimum number of leading characters before PrefixQuery is used (4).

Declaration

public const int DEFAULT_MIN_PREFIX_CHARS = 4

Field Value

Type	Description
int

EXACT_TEXT_FIELD_NAME

Field name used for the indexed text, as a Lucene.Net.Documents.StringField, for exact lookup.

Declaration

protected const string EXACT_TEXT_FIELD_NAME = "exacttext"

Field Value

Type	Description
string

TEXT_FIELD_NAME

Field name used for the indexed text.

Declaration

protected const string TEXT_FIELD_NAME = "text"

Field Value

Type	Description
string

m_indexAnalyzer

Analyzer used at index time

Declaration

protected readonly Analyzer m_indexAnalyzer

Field Value

Type	Description
Analyzer

m_queryAnalyzer

Analyzer used at search time

Declaration

protected readonly Analyzer m_queryAnalyzer

Field Value

Type	Description
Analyzer

m_searcherMgr

Lucene.Net.Search.IndexSearcher used for lookups.

Declaration

protected SearcherManager m_searcherMgr

Field Value

Type	Description
SearcherManager

Properties

Count

Get the number of entries the lookup was built with

Declaration

public override long Count { get; }

Property Value

Type	Description
long	total number of suggester entries

Overrides

Lookup.Count

Methods

Add(BytesRef, IEnumerable<BytesRef>, long, BytesRef)

Adds a new suggestion. Be sure to use Update(BytesRef, IEnumerable<BytesRef>, long, BytesRef) instead if you want to replace a previous suggestion. After adding or updating a batch of new suggestions, you must call Refresh() in the end in order to see the suggestions in DoLookup(string, IEnumerable<BytesRef>, int, bool, bool)

Declaration

public virtual void Add(BytesRef text, IEnumerable<BytesRef> contexts, long weight, BytesRef payload)

Parameters

Type	Name	Description
BytesRef	text
IEnumerable<BytesRef>	contexts
long	weight
BytesRef	payload

AddNonMatch(StringBuilder, string)

Called while highlighting a single result, to append a non-matching chunk of text from the suggestion to the provided fragments list.

Declaration

protected virtual void AddNonMatch(StringBuilder sb, string text)

Parameters

Type	Name	Description
StringBuilder	sb	The StringBuilder to append to
string	text	The text chunk to add

AddPrefixMatch(StringBuilder, string, string, string)

Called while highlighting a single result, to append a matched prefix token, to the provided fragments list.

Declaration

protected virtual void AddPrefixMatch(StringBuilder sb, string surface, string analyzed, string prefixToken)

Parameters

Type	Name	Description
StringBuilder	sb	The StringBuilder to append to
string	surface	The fragment of the surface form (indexed during Build(IInputEnumerator), corresponding to this match
string	analyzed	The analyzed token that matched
string	prefixToken	The prefix of the token that matched

AddWholeMatch(StringBuilder, string, string)

Called while highlighting a single result, to append the whole matched token to the provided fragments list.

Declaration

protected virtual void AddWholeMatch(StringBuilder sb, string surface, string analyzed)

Parameters

Type	Name	Description
StringBuilder	sb	The StringBuilder to append to
string	surface	The surface form (original) text
string	analyzed	The analyzed token corresponding to the surface form text

Build(IInputEnumerator)

Builds up a new internal Lookup representation based on the given IInputEnumerator. The implementation might re-sort the data internally.

Declaration

public override void Build(IInputEnumerator enumerator)

Parameters

Type	Name	Description
IInputEnumerator	enumerator

Overrides

Lookup.Build(IInputEnumerator)

Commit()

Analyzes the input text and then suggests matches based on prefix matches to any tokens in the indexed text. This also highlights the tokens that match.

This suggester supports payloads. Matches are sorted only by the suggest weight; it would be nice to support blended score + weight sort in the future. This means this suggester best applies when there is a strong a-priori ranking of all the suggestions.

This suggester supports contexts, however the contexts must be valid utf8 (arbitrary binary terms will not work).

Note

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

Declaration

public void Commit()

CreateResults(IndexSearcher, TopFieldDocs, int, string, bool, ICollection<string>, string)

Create the results based on the search hits. Can be overridden by subclass to add particular behavior (e.g. weight transformation)

Declaration

protected virtual IList<Lookup.LookupResult> CreateResults(IndexSearcher searcher, TopFieldDocs hits, int num, string charSequence, bool doHighlight, ICollection<string> matchedTokens, string prefixToken)

Parameters

Type	Name	Description
IndexSearcher	searcher
TopFieldDocs	hits
int	num
string	charSequence
bool	doHighlight
ICollection<string>	matchedTokens
string	prefixToken

Returns

Type	Description
IList<Lookup.LookupResult>

Exceptions

Type	Condition
IOException	If there are problems reading fields from the underlying Lucene index.

Dispose()

Performs application-defined tasks associated with freeing, releasing, or resetting unmanaged resources.

Declaration

public void Dispose()

Dispose(bool)

Analyzes the input text and then suggests matches based on prefix matches to any tokens in the indexed text. This also highlights the tokens that match.

This suggester supports payloads. Matches are sorted only by the suggest weight; it would be nice to support blended score + weight sort in the future. This means this suggester best applies when there is a strong a-priori ranking of all the suggestions.

This suggester supports contexts, however the contexts must be valid utf8 (arbitrary binary terms will not work).

Note

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

Declaration

protected virtual void Dispose(bool disposing)

Parameters

Type	Name	Description
bool	disposing

DoLookup(string, IEnumerable<BytesRef>, bool, int)

Look up a key and return possible completion for this key.

Declaration

public override IList<Lookup.LookupResult> DoLookup(string key, IEnumerable<BytesRef> contexts, bool onlyMorePopular, int num)

Parameters

Type	Name	Description
string	key	lookup key. Depending on the implementation this may be a prefix, misspelling, or even infix.
IEnumerable<BytesRef>	contexts	contexts to filter the lookup by, or null if all contexts are allowed; if the suggestion contains any of the contexts, it's a match
bool	onlyMorePopular	return only more popular results
int	num	maximum number of results to return

Returns

Type	Description
IList<Lookup.LookupResult>	a list of possible completions, with their relative weight (e.g. popularity)

Overrides

Lookup.DoLookup(string, IEnumerable<BytesRef>, bool, int)

DoLookup(string, IEnumerable<BytesRef>, int, bool, bool)

Retrieve suggestions, specifying whether all terms must match (allTermsRequired) and whether the hits should be highlighted (doHighlight).

Declaration

public virtual IList<Lookup.LookupResult> DoLookup(string key, IEnumerable<BytesRef> contexts, int num, bool allTermsRequired, bool doHighlight)

Parameters

Type	Name	Description
string	key
IEnumerable<BytesRef>	contexts
int	num
bool	allTermsRequired
bool	doHighlight

Returns

Type	Description
IList<Lookup.LookupResult>

DoLookup(string, int, bool, bool)

Lookup, without any context.

Declaration

public virtual IList<Lookup.LookupResult> DoLookup(string key, int num, bool allTermsRequired, bool doHighlight)

Parameters

Type	Name	Description
string	key
int	num
bool	allTermsRequired
bool	doHighlight

Returns

Type	Description
IList<Lookup.LookupResult>

FinishQuery(BooleanQuery, bool)

Subclass can override this to tweak the Query before searching.

Declaration

protected virtual Query FinishQuery(BooleanQuery bq, bool allTermsRequired)

Parameters

Type	Name	Description
BooleanQuery	bq
bool	allTermsRequired

Returns

Type	Description
Query

GetDirectory(DirectoryInfo)

Subclass can override to choose a specific Lucene.Net.Store.Directory implementation.

Declaration

protected virtual Directory GetDirectory(DirectoryInfo path)

Parameters

Type	Name	Description
DirectoryInfo	path

Returns

Type	Description
Directory

GetLastTokenQuery(string)

This is called if the last token isn't ended (e.g. user did not type a space after it). Return an appropriate Lucene.Net.Search.Query clause to add to the Lucene.Net.Search.BooleanQuery.

Declaration

protected virtual Query GetLastTokenQuery(string token)

Parameters

Type	Name	Description
string	token

Returns

Type	Description
Query

GetSizeInBytes()

Get the size of the underlying lookup implementation in memory

Declaration

public override long GetSizeInBytes()

Returns

Type	Description
long	ram size of the lookup implementation in bytes

Overrides

Lookup.GetSizeInBytes()

GetTextFieldType()

Subclass can override this method to change the field type of the text field e.g. to change the index options

Declaration

protected virtual FieldType GetTextFieldType()

Returns

Type	Description
FieldType

Highlight(string, ICollection<string>, string)

Override this method to customize the Object representing a single highlighted suggestions; the result is set on each HighlightKey member.

Declaration

protected virtual object Highlight(string text, ICollection<string> matchedTokens, string prefixToken)

Parameters

Type	Name	Description
string	text
ICollection<string>	matchedTokens
string	prefixToken

Returns

Type	Description
object

Load(DataInput)

Discard current lookup data and load it from a previously saved copy. Optional operation.

Declaration

public override bool Load(DataInput @out)

Parameters

Type	Name	Description
DataInput	out

Returns

Type	Description
bool	true if completed successfully, false if unsuccessful or not supported.

Overrides

Lookup.Load(DataInput)

Exceptions

Type	Condition
IOException	when fatal IO error occurs.

Refresh()

Reopens the underlying searcher; it's best to "batch up" many additions/updates, and then call refresh once in the end.

Declaration

public virtual void Refresh()

Store(DataOutput)

Persist the constructed lookup data to a directory. Optional operation.

Declaration

public override bool Store(DataOutput @in)

Parameters

Type	Name	Description
DataOutput	in

Returns

Type	Description
bool	true if successful, false if unsuccessful or not supported.

Overrides

Lookup.Store(DataOutput)

Exceptions

Type	Condition
IOException	when fatal IO error occurs.

Update(BytesRef, IEnumerable<BytesRef>, long, BytesRef)

Updates a previous suggestion, matching the exact same text as before. Use this to change the weight or payload of an already added suggstion. If you know this text is not already present you can use Add(BytesRef, IEnumerable<BytesRef>, long, BytesRef) instead. After adding or updating a batch of new suggestions, you must call Refresh() in the end in order to see the suggestions in DoLookup(string, IEnumerable<BytesRef>, int, bool, bool)

Declaration

public virtual void Update(BytesRef text, IEnumerable<BytesRef> contexts, long weight, BytesRef payload)

Parameters

Type	Name	Description
BytesRef	text
IEnumerable<BytesRef>	contexts
long	weight
BytesRef	payload

Implements

IDisposable