org.elasticsearch.search.rescore

Interface Rescorer

All Known Implementing Classes:

QueryRescorer

public interface Rescorer

A query rescorer interface used to re-rank the Top-K results of a previously executed search.

Method Summary

Methods

Modifier and Type	Method and Description
org.apache.lucene.search.Explanation	explain(int topLevelDocId, SearchContext context, RescoreSearchContext rescoreContext, org.apache.lucene.search.Explanation sourceExplanation) Executes an Explanation phase on the rescorer.
void	extractTerms(SearchContext context, RescoreSearchContext rescoreContext, Set<org.apache.lucene.index.Term> termsSet) Extracts all terms needed to exectue this Rescorer.
String	name() Returns the name of this rescorer
RescoreSearchContext	parse(XContentParser parser, SearchContext context) Parses the RescoreSearchContext for this impelementation
org.apache.lucene.search.TopDocs	rescore(org.apache.lucene.search.TopDocs topDocs, SearchContext context, RescoreSearchContext rescoreContext) Modifies the result of the previously executed search (TopDocs) in place based on the given RescoreSearchContext.

Method Detail

name

String name()

Returns the name of this rescorer

rescore

org.apache.lucene.search.TopDocs rescore(org.apache.lucene.search.TopDocs topDocs,
                                       SearchContext context,
                                       RescoreSearchContext rescoreContext)
                                         throws IOException

Modifies the result of the previously executed search (TopDocs) in place based on the given RescoreSearchContext.

Parameters:

topDocs - the result of the previously exectued search

context - the current SearchContext. This will never be null.

rescoreContext - the RescoreSearchContext. This will never be null

Throws:

IOException - if an IOException occurs during rescoring

explain

org.apache.lucene.search.Explanation explain(int topLevelDocId,
                                           SearchContext context,
                                           RescoreSearchContext rescoreContext,
                                           org.apache.lucene.search.Explanation sourceExplanation)
                                             throws IOException

Executes an Explanation phase on the rescorer.

Parameters:

topLevelDocId - the global / top-level document ID to explain

context - the explanation for the results being fed to this rescorer

rescoreContext - context for this rescorer

sourceExplanation - explanation of the source of the documents being fed into this rescore

Returns:

the explain for the given top level document ID.

Throws:

IOException - if an IOException occurs

parse

RescoreSearchContext parse(XContentParser parser,
                         SearchContext context)
                           throws IOException

Parses the RescoreSearchContext for this impelementation

Parameters:

parser - the parser to read the context from

context - the current search context

Returns:

the parsed RescoreSearchContext

Throws:

IOException - if an IOException occurs while parsing the context

extractTerms

void extractTerms(SearchContext context,
                RescoreSearchContext rescoreContext,
                Set<org.apache.lucene.index.Term> termsSet)

Extracts all terms needed to exectue this Rescorer. This method is executed in a distributed frequency collection roundtrip for SearchType.DFS_QUERY_AND_FETCH and SearchType.DFS_QUERY_THEN_FETCH