Class TermVectorsWriter

Codec API for writing term vectors:

  1. For every document, StartDocument(int) is called, informing the Codec how many fields will be written.
  2. StartField(FieldInfo, int, bool, bool, bool) is called for each field in the document, informing the codec how many terms will be written for that field, and whether or not positions, offsets, or payloads are enabled.
  3. Within each field, StartTerm(BytesRef, int) is called for each term.
  4. If offsets and/or positions are enabled, then AddPosition(int, int, int, BytesRef) will be called for each term occurrence.
  5. After all documents have been written, Finish(FieldInfos, int) is called for verification/sanity-checks.
  6. Finally the writer is disposed (Dispose(bool))

Note

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

Inheritance
object
TermVectorsWriter
CompressingTermVectorsWriter
Lucene40TermVectorsWriter
Implements
Inherited Members
Namespace: Lucene.Net.Codecs
Assembly: Lucene.Net.dll
Syntax
public abstract class TermVectorsWriter : IDisposable

Constructors

TermVectorsWriter()

Sole constructor. (For invocation by subclass constructors, typically implicit.)

Declaration
protected TermVectorsWriter()

Properties

Comparer

Return the IComparer{BytesRef} used to sort terms before feeding to this API.

Declaration
public abstract IComparer<BytesRef> Comparer { get; }
Property Value
Type Description
IComparer<BytesRef>

Methods

Abort()

Aborts writing entirely, implementation should remove any partially-written files, etc.

Declaration
public abstract void Abort()

AddAllDocVectors(Fields, MergeState)

Safe (but, slowish) default method to write every vector field in the document.

Declaration
protected void AddAllDocVectors(Fields vectors, MergeState mergeState)
Parameters
Type Name Description
Fields vectors
MergeState mergeState

AddPosition(int, int, int, BytesRef)

Adds a term position and offsets.

Declaration
public abstract void AddPosition(int position, int startOffset, int endOffset, BytesRef payload)
Parameters
Type Name Description
int position
int startOffset
int endOffset
BytesRef payload

AddProx(int, DataInput, DataInput)

Called by IndexWriter when writing new segments.

This is an expert API that allows the codec to consume positions and offsets directly from the indexer.

The default implementation calls AddPosition(int, int, int, BytesRef), but subclasses can override this if they want to efficiently write all the positions, then all the offsets, for example.

NOTE: this API is extremely expert and subject to change or removal!!!

Note

This API is for internal purposes only and might change in incompatible ways in the next release.

Declaration
public virtual void AddProx(int numProx, DataInput positions, DataInput offsets)
Parameters
Type Name Description
int numProx
DataInput positions
DataInput offsets

Dispose()

Disposes all resources used by this object.

Declaration
public void Dispose()

Dispose(bool)

Implementations must override and should dispose all resources used by this instance.

Declaration
protected abstract void Dispose(bool disposing)
Parameters
Type Name Description
bool disposing

Finish(FieldInfos, int)

Called before Dispose(bool), passing in the number of documents that were written. Note that this is intentionally redundant (equivalent to the number of calls to StartDocument(int), but a Codec should check that this is the case to detect the bug described in LUCENE-1282.

Declaration
public abstract void Finish(FieldInfos fis, int numDocs)
Parameters
Type Name Description
FieldInfos fis
int numDocs

FinishDocument()

Called after a doc and all its fields have been added.

Declaration
public virtual void FinishDocument()

FinishField()

Called after a field and all its terms have been added.

Declaration
public virtual void FinishField()

FinishTerm()

Called after a term and all its positions have been added.

Declaration
public virtual void FinishTerm()

Merge(MergeState)

Merges in the term vectors from the readers in mergeState. The default implementation skips over deleted documents, and uses StartDocument(int), StartField(FieldInfo, int, bool, bool, bool), StartTerm(BytesRef, int), AddPosition(int, int, int, BytesRef), and Finish(FieldInfos, int), returning the number of documents that were written. Implementations can override this method for more sophisticated merging (bulk-byte copying, etc).

Declaration
public virtual int Merge(MergeState mergeState)
Parameters
Type Name Description
MergeState mergeState
Returns
Type Description
int

StartDocument(int)

Called before writing the term vectors of the document. StartField(FieldInfo, int, bool, bool, bool) will be called numVectorFields times. Note that if term vectors are enabled, this is called even if the document has no vector fields, in this case numVectorFields will be zero.

Declaration
public abstract void StartDocument(int numVectorFields)
Parameters
Type Name Description
int numVectorFields

StartField(FieldInfo, int, bool, bool, bool)

Called before writing the terms of the field. StartTerm(BytesRef, int) will be called numTerms times.

Declaration
public abstract void StartField(FieldInfo info, int numTerms, bool positions, bool offsets, bool payloads)
Parameters
Type Name Description
FieldInfo info
int numTerms
bool positions
bool offsets
bool payloads

StartTerm(BytesRef, int)

Adds a term and its term frequency freq. If this field has positions and/or offsets enabled, then AddPosition(int, int, int, BytesRef) will be called freq times respectively.

Declaration
public abstract void StartTerm(BytesRef term, int freq)
Parameters
Type Name Description
BytesRef term
int freq

Implements