org.apache.lucene.codecs

Class PostingsConsumer

java.lang.Object

org.apache.lucene.codecs.PostingsConsumer

Direct Known Subclasses:

PostingsWriterBase

public abstract class PostingsConsumer
extends Object

Abstract API that consumes postings for an individual term.

The lifecycle is:

1. PostingsConsumer is returned for each term by TermsConsumer.startTerm(BytesRef).
2. startDoc(int, int) is called for each document where the term occurs, specifying id and term frequency for that document.
3. If positions are enabled for the field, then addPosition(int, BytesRef, int, int) will be called for each occurrence in the document.
4. finishDoc() is called when the producer is done adding positions to the document.

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

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	PostingsConsumer() Sole constructor.

Method Summary

Methods

Modifier and Type	Method and Description
abstract void	addPosition(int position, BytesRef payload, int startOffset, int endOffset) Add a new position & payload, and start/end offset.
abstract void	finishDoc() Called when we are done adding positions & payloads for each doc.
TermStats	merge(MergeState mergeState, FieldInfo.IndexOptions indexOptions, DocsEnum postings, FixedBitSet visitedDocs) Default merge impl: append documents, mapping around deletes
abstract void	startDoc(int docID, int freq) Adds a new doc in this term.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

PostingsConsumer

protected PostingsConsumer()

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

Method Detail

startDoc

public abstract void startDoc(int docID,
            int freq)
                       throws IOException

Adds a new doc in this term. freq will be -1 when term frequencies are omitted for the field.

Throws:

IOException

addPosition

public abstract void addPosition(int position,
               BytesRef payload,
               int startOffset,
               int endOffset)
                          throws IOException

Add a new position & payload, and start/end offset. A null payload means no payload; a non-null payload with zero length also means no payload. Caller may reuse the BytesRef for the payload between calls (method must fully consume the payload). startOffset and endOffset will be -1 when offsets are not indexed.

Throws:

IOException

finishDoc

public abstract void finishDoc()
                        throws IOException

Called when we are done adding positions & payloads for each doc.

Throws:

IOException

merge

public TermStats merge(MergeState mergeState,
              FieldInfo.IndexOptions indexOptions,
              DocsEnum postings,
              FixedBitSet visitedDocs)
                throws IOException

Default merge impl: append documents, mapping around deletes

Throws:

IOException