Package org.apache.lucene.search

Class TotalHitCountCollectorManager

java.lang.Object

org.apache.lucene.search.TotalHitCountCollectorManager

All Implemented Interfaces:

CollectorManager<TotalHitCountCollector,Integer>

public class TotalHitCountCollectorManager
extends Object
implements CollectorManager<TotalHitCountCollector,Integer>

Collector manager based on TotalHitCountCollector that allows users to parallelize counting the number of hits, expected to be used mostly wrapped in MultiCollectorManager. For cases when this is the only collector manager used, IndexSearcher.count(Query) should be called instead of IndexSearcher.search(Query, CollectorManager) as the former is faster whenever the count can be returned directly from the index statistics.

Constructor Summary

Constructors

Constructor	Description
TotalHitCountCollectorManager()

Method Summary

Modifier and Type	Method	Description
TotalHitCountCollector	newCollector()	Return a new Collector.
Integer	reduce(Collection<TotalHitCountCollector> collectors)	Reduce the results of individual collectors into a meaningful result.

Methods inherited from class java.lang.Object

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

Constructor Details

TotalHitCountCollectorManager

public TotalHitCountCollectorManager()

Method Details

newCollector

public TotalHitCountCollector newCollector()
                                    throws IOException

Description copied from interface: CollectorManager

Return a new Collector. This must return a different instance on each call.

Specified by:

newCollector in interface CollectorManager<TotalHitCountCollector,Integer>

Throws:

IOException

reduce

public Integer reduce(Collection<TotalHitCountCollector> collectors)
               throws IOException

Description copied from interface: CollectorManager

Reduce the results of individual collectors into a meaningful result. For instance a TopDocsCollector would compute the top docs of each collector and then merge them using TopDocs.merge(int, TopDocs[]). This method must be called after collection is finished on all provided collectors.

Specified by:

reduce in interface CollectorManager<TotalHitCountCollector,Integer>

Throws:

IOException