org.apache.lucene.codecs

Class NormsConsumer

java.lang.Object

org.apache.lucene.codecs.NormsConsumer

All Implemented Interfaces:

Closeable, AutoCloseable

public abstract class NormsConsumer
extends Object
implements Closeable

Abstract API that consumes normalization values. Concrete implementations of this actually do "something" with the norms (write it into the index in a specific format).

The lifecycle is:

1. NormsConsumer is created by NormsFormat.normsConsumer(SegmentWriteState).
2. addNormsField(org.apache.lucene.index.FieldInfo, java.lang.Iterable<java.lang.Number>) is called for each field with normalization values. The API is a "pull" rather than "push", and the implementation is free to iterate over the values multiple times (Iterable.iterator()).
3. After all fields are added, the consumer is Closeable.close()d.

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

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	NormsConsumer() Sole constructor.

Method Summary

Modifier and Type	Method and Description
abstract void	addNormsField(FieldInfo field, Iterable<Number> values) Writes normalization values for a field.
void	merge(MergeState mergeState) Merges in the fields from the readers in mergeState.
void	mergeNormsField(FieldInfo fieldInfo, MergeState mergeState, List<NumericDocValues> toMerge) Merges the norms from toMerge.

Methods inherited from class java.lang.Object

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

Methods inherited from interface java.io.Closeable

close

Constructor Detail

NormsConsumer

protected NormsConsumer()

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

Method Detail

addNormsField

public abstract void addNormsField(FieldInfo field,
                                   Iterable<Number> values)
                            throws IOException

Writes normalization values for a field.

Parameters:

field - field information

values - Iterable of numeric values (one for each document).

Throws:

IOException - if an I/O error occurred.

merge

public void merge(MergeState mergeState)
           throws IOException

Merges in the fields from the readers in mergeState. The default implementation calls mergeNormsField(org.apache.lucene.index.FieldInfo, org.apache.lucene.index.MergeState, java.util.List<org.apache.lucene.index.NumericDocValues>) for each field, filling segments with missing norms for the field with zeros. Implementations can override this method for more sophisticated merging (bulk-byte copying, etc).

Throws:

IOException

mergeNormsField

public void mergeNormsField(FieldInfo fieldInfo,
                            MergeState mergeState,
                            List<NumericDocValues> toMerge)
                     throws IOException

Merges the norms from toMerge.

The default implementation calls addNormsField(org.apache.lucene.index.FieldInfo, java.lang.Iterable<java.lang.Number>), passing an Iterable that merges and filters deleted documents on the fly.

Throws:

IOException