Package org.apache.lucene.search
Interface Collector
- All Known Implementing Classes:
CachingCollector
,FilterCollector
,MultiCollector
,PositiveScoresOnlyCollector
,SimpleCollector
,TimeLimitingCollector
,TopDocsCollector
,TopFieldCollector
,TopScoreDocCollector
,TotalHitCountCollector
public interface Collector
Expert: Collectors are primarily meant to be used to gather raw results from a search, and
implement sorting or custom result filtering, collation, etc.
Lucene's core collectors are derived from Collector
and SimpleCollector
.
Likely your application can use one of these classes, or subclass TopDocsCollector
,
instead of implementing Collector directly:
TopDocsCollector
is an abstract base class that assumes you will retrieve the top N docs, according to some criteria, after collection is done.TopScoreDocCollector
is a concrete subclassTopDocsCollector
and sorts according to score + docID. This is used internally by theIndexSearcher
search methods that do not take an explicitSort
. It is likely the most frequently used collector.TopFieldCollector
subclassesTopDocsCollector
and sorts according to a specifiedSort
object (sort by field). This is used internally by theIndexSearcher
search methods that take an explicitSort
.TimeLimitingCollector
, which wraps any other Collector and aborts the search if it's taken too much time.PositiveScoresOnlyCollector
wraps any other Collector and prevents collection of hits whose score is <= 0.0
- WARNING: This API is experimental and might change in incompatible ways in the next release.
-
Method Summary
Modifier and TypeMethodDescriptiongetLeafCollector
(LeafReaderContext context) Create a newcollector
to collect the given context.Indicates what features are required from the scorer.
-
Method Details
-
getLeafCollector
Create a newcollector
to collect the given context.- Parameters:
context
- next atomic reader context- Throws:
IOException
-
scoreMode
ScoreMode scoreMode()Indicates what features are required from the scorer.
-