TextIndexer class abstract

Interface for classes that construct and maintain a InvertedIndex for a collection of documents (corpus).

Text or documents can be indexed by calling the following methods:

• TextIndexer.indexJson indexes the fields in a Map<String, dynamic> document;
• TextIndexer.indexText indexes text from a text document;
• TextIndexer.indexTokens indexes text from a text document;
• TextIndexer.indexDocumentStream indexes documents emitted by a stream of {docId : document} map entries;
• TextIndexer.indexCollectionStream indexes the documents emitted by a JsonCollection stream; and
• indexCollection indexes the fields of all the documents in a Map<String, dynamic> document collection.

Implemented types

• InvertedIndex

Implementers

• TextIndexerMixin

Constructors

TextIndexer()

Properties

analyzer → TextAnalyzer

The text analyser that extracts tokens from text for the index.

no setter, inherited

hashCode → int

The hash code for this object.

no setter, inherited

k → int

The length of k-gram entries in the k-gram index.

no setter, inherited

nGramRange → NGramRange?

The minimum and maximum length of n-grams in the index.

no setter, inherited

runtimeType → Type

A representation of the runtime type of the object.

no setter, inherited

vocabularyLength → Future<Ft>

Returns the number of terms in the vocabulary (N).

no setter, inherited

zones → ZoneWeightMap

Maps zone names to their relative weight in the index.

no setter, inherited

Methods

dispose() → Future<void>

Cancels any stream all listeners.

getCollectionSize() → Future<int>

Asynchronously returns the total number of documents in the indexed collection.

inherited

getDictionary([Iterable<String>? terms]) → Future<DftMap>

Asynchronously retrieves a DftMap for the terms from a DftMap repository.

inherited

getKeywordPostings(Iterable<String> keywords) → Future<KeywordPostingsMap>

Asynchronously retrieves PostingsMapEntry entities for the terms from a PostingsMap repository.

inherited

getKGramIndex(Iterable<String> kGrams) → Future<KGramsMap>

Asynchronously retrieves a KGramsMap for the terms from a KGramsMap repository.

inherited

getPostings(Iterable<String> terms) → Future<PostingsMap>

Asynchronously retrieves PostingsMapEntry entities for the terms from a PostingsMap repository.

inherited

indexCollection(Map<String, Map<String, dynamic>> collection, {TokenFilter? tokenFilter}) → Future<void>

Indexes the InvertedIndex.zones of all the documents in collection.

indexCollectionStream(Stream<JsonCollection> collectionStream, {TokenFilter? tokenFilter}) → void

Indexes the documents emitted by collectionStream.

indexDocumentStream(Stream<MapEntry<String, JSON>> documentStream, {TokenFilter? tokenFilter}) → void

Indexes the documents emitted by documentStream.

indexJson(String docId, Map<String, dynamic> json, {TokenFilter? tokenFilter}) → Future<void>

Indexes the InvertedIndex.zones in a json document, returning a list of DocPostingsMapEntry.

indexText(String docId, String docText, {String? zone, TokenFilter? tokenFilter}) → Future<void>

Indexes a text document, returning a PostingsMap.

indexTokens(String docId, Iterable<Token> tokens) → Future<void>

Updates the index with the tokens for docId.

noSuchMethod(Invocation invocation) → dynamic

Invoked when a nonexistent method or property is accessed.

inherited

toString() → String

A string representation of this object.

inherited

updateIndexes(PostingsMap postings, KeywordPostingsMap keywordPostings, Iterable<Token> tokens) → Future<void>

The updateIndexes method updates the DftMap, PostingsMap, KeywordPostingsMap and KGramsMap.

upsertDictionary(DftMap values) → Future<void>

Inserts values into a DftMap repository, overwriting them if they already exist.

inherited

upsertKeywordPostings(KeywordPostingsMap values) → Future<void>

Inserts values into a PostingsMap repository, overwriting them if they already exist.

inherited

upsertKGramIndex(KGramsMap values) → Future<void>

Inserts values into a KGramsMap repository, overwriting any existing entries.

inherited

upsertPostings(PostingsMap values) → Future<void>

Inserts values into a PostingsMap repository, overwriting them if they already exist.

inherited

Operators

operator ==(Object other) → bool

The equality operator.

inherited