Namespace Lucene.Net.Codecs.BlockTerms

Pluggable term index / block terms dictionary implementations.

Classes

BlockTermsReader

Handles a terms dict, but decouples all details of doc/freqs/positions reading to an instance of Lucene.Net.Codecs.PostingsReaderBase. This class is reusable for codecs that use a different format for docs/freqs/positions (though codecs are also free to make their own terms dict impl).

This class also interacts with an instance of TermsIndexReaderBase, to abstract away the specific implementation of the terms dict index.

Note

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

BlockTermsWriter

Writes terms dict, block-encoding (column stride) each term's metadata for each set of terms between two index terms.

Note

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

FixedGapTermsIndexReader

TermsIndexReaderBase for simple every Nth terms indexes.

Note

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

FixedGapTermsIndexWriter

Selects every Nth term as and index term, and hold term bytes (mostly) fully expanded in memory. This terms index supports seeking by ord. See VariableGapTermsIndexWriter for a more memory efficient terms index that does not support seeking by ord.

Note

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

TermsIndexReaderBase

BlockTermsReader interacts with an instance of this class to manage its terms index. The writer must accept indexed terms (many pairs of Lucene.Net.Util.BytesRef text + long fileOffset), and then this reader must be able to retrieve the nearest index term to a provided term text.

Note

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

TermsIndexReaderBase.FieldIndexEnum

Similar to Lucene.Net.Index.TermsEnum, except, the only "metadata" it reports for a given indexed term is the long fileOffset into the main terms dictionary file.

TermsIndexWriterBase

Base class for terms index implementations to plug into BlockTermsWriter.

Note

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

TermsIndexWriterBase.FieldWriter

Terms index API for a single field.

VariableGapTermsIndexReader

See VariableGapTermsIndexWriter.

Note

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

VariableGapTermsIndexWriter

Selects index terms according to provided pluggable VariableGapTermsIndexWriter.IndexTermSelector, and stores them in a prefix trie that's loaded entirely in RAM stored as an Lucene.Net.Util.Fst.FST<T>. This terms index only supports unsigned byte term sort order (unicode codepoint order when the bytes are UTF8).

Note

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

VariableGapTermsIndexWriter.EveryNOrDocFreqTermSelector

Sets an index term when docFreq >= docFreqThresh, or every interval terms. This should reduce seek time to high docFreq terms.

VariableGapTermsIndexWriter.EveryNTermSelector

Pluggable term index / block terms dictionary implementations.

VariableGapTermsIndexWriter.IndexTermSelector

Hook for selecting which terms should be placed in the terms index.

NewField(FieldInfo) is called at the start of each new field, and IsIndexTerm(BytesRef, TermStats) for each term in that field.

Note

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