public class TermDistinctValuesCollector extends AbstractDistinctValuesCollector<TermDistinctValuesCollector.GroupCount>
AbstractDistinctValuesCollector
that relies
on SortedDocValues
to count the distinct values per group.Modifier and Type | Class and Description |
---|---|
static class |
TermDistinctValuesCollector.GroupCount
Holds distinct values for a single group.
|
Constructor and Description |
---|
TermDistinctValuesCollector(String groupField,
String countField,
Collection<SearchGroup<BytesRef>> groups)
Constructs
TermDistinctValuesCollector instance. |
Modifier and Type | Method and Description |
---|---|
void |
collect(int doc)
Called once for every document matching a query, with the unbased document
number.
|
protected void |
doSetNextReader(LeafReaderContext context)
This method is called before collecting
context . |
List<TermDistinctValuesCollector.GroupCount> |
getGroups()
Returns all unique values for each top N group.
|
boolean |
needsScores()
Indicates if document scores are needed by this collector.
|
getLeafCollector, setScorer
public TermDistinctValuesCollector(String groupField, String countField, Collection<SearchGroup<BytesRef>> groups)
TermDistinctValuesCollector
instance.groupField
- The field to group bycountField
- The field to count distinct values forgroups
- The top N groups, collected during the first phase searchpublic void collect(int doc) throws IOException
LeafCollector
Note: The collection of the current segment can be terminated by throwing
a CollectionTerminatedException
. In this case, the last docs of the
current LeafReaderContext
will be skipped and IndexSearcher
will swallow the exception and continue collection with the next leaf.
Note: This is called in an inner search loop. For good search performance,
implementations of this method should not call IndexSearcher.doc(int)
or
IndexReader.document(int)
on every hit.
Doing so can slow searches by an order of magnitude or more.
collect
in interface LeafCollector
collect
in class SimpleCollector
IOException
public List<TermDistinctValuesCollector.GroupCount> getGroups()
AbstractDistinctValuesCollector
getGroups
in class AbstractDistinctValuesCollector<TermDistinctValuesCollector.GroupCount>
protected void doSetNextReader(LeafReaderContext context) throws IOException
SimpleCollector
context
.doSetNextReader
in class SimpleCollector
IOException
public boolean needsScores()
Collector
true
if scores are needed.Copyright © 2000–2015 The Apache Software Foundation. All rights reserved.