org.elasticsearch.search.aggregations

Class AggregatorBase

java.lang.Object

org.elasticsearch.search.aggregations.BucketCollector

org.elasticsearch.search.aggregations.Aggregator

org.elasticsearch.search.aggregations.AggregatorBase

All Implemented Interfaces:

AutoCloseable, org.apache.lucene.search.Collector, Releasable

Direct Known Subclasses:

BucketsAggregator, MetricsAggregator, NonCollectingAggregator

public abstract class AggregatorBase
extends Aggregator

Base implementation for concrete aggregators.

Nested Class Summary

Nested classes/interfaces inherited from class org.elasticsearch.search.aggregations.Aggregator

Aggregator.Parser, Aggregator.SubAggCollectionMode

Field Summary

Fields

Modifier and Type	Field and Description
protected BucketCollector	collectableSubAggregators
protected AggregationContext	context
protected String	name
protected Aggregator	parent
protected Aggregator[]	subAggregators

Fields inherited from class org.elasticsearch.search.aggregations.BucketCollector

NO_OP_COLLECTOR

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	AggregatorBase(String name, AggregatorFactories factories, AggregationContext context, Aggregator parent, List<PipelineAggregator> pipelineAggregators, Map<String,Object> metaData) Constructs a new Aggregator.

Method Summary

Methods

Modifier and Type	Method and Description
protected InternalAggregations	buildEmptySubAggregations()
void	close() Called upon release of the aggregator.
AggregationContext	context() Return the AggregationContext attached with this Aggregator.
protected void	doClose() Release instance-specific data.
protected void	doPostCollection() Can be overriden by aggregator implementation to be called back when the collection phase ends.
protected void	doPreCollection() Can be overriden by aggregator implementation to be called back when the collection phase starts.
DeferringBucketCollector	getDeferringCollector()
LeafBucketCollector	getLeafCollector(org.apache.lucene.index.LeafReaderContext ctx)
protected abstract LeafBucketCollector	getLeafCollector(org.apache.lucene.index.LeafReaderContext ctx, LeafBucketCollector sub) Get a LeafBucketCollector for the given ctx, which should delegate to the given collector.
Map<String,Object>	metaData()
String	name() Return the name of this aggregator.
boolean	needsScores() Most aggregators don't need scores, make sure to extend this method if your aggregator needs them.
Aggregator	parent() Return the parent aggregator.
List<PipelineAggregator>	pipelineAggregators()
void	postCollection() Called after collection of all document is done.
void	preCollection() Pre collection callback.
protected void	runDeferredCollections(long... bucketOrds)
protected boolean	shouldDefer(Aggregator aggregator) This method should be overidden by subclasses that want to defer calculation of a child aggregation until a first pass is complete and a set of buckets has been pruned.
Aggregator	subAggregator(String aggName) Return the sub aggregator with the provided name.
Aggregator[]	subAggregators()
String	toString()

Methods inherited from class org.elasticsearch.search.aggregations.Aggregator

buildAggregation, buildEmptyAggregation, descendsFromBucketAggregator

Methods inherited from class org.elasticsearch.search.aggregations.BucketCollector

wrap

Methods inherited from class java.lang.Object

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

Field Detail

name

protected final String name

parent

protected final Aggregator parent

context

protected final AggregationContext context

subAggregators

protected final Aggregator[] subAggregators

collectableSubAggregators

protected BucketCollector collectableSubAggregators

Constructor Detail

AggregatorBase

protected AggregatorBase(String name,
              AggregatorFactories factories,
              AggregationContext context,
              Aggregator parent,
              List<PipelineAggregator> pipelineAggregators,
              Map<String,Object> metaData)
                  throws IOException

Constructs a new Aggregator.

Parameters:

name - The name of the aggregation

factories - The factories for all the sub-aggregators under this aggregator

context - The aggregation context

parent - The parent aggregator (may be null for top level aggregators)

metaData - The metaData associated with this aggregator

Throws:

IOException

Method Detail

needsScores

public boolean needsScores()

Most aggregators don't need scores, make sure to extend this method if your aggregator needs them.

metaData

public Map<String,Object> metaData()

pipelineAggregators

public List<PipelineAggregator> pipelineAggregators()

getLeafCollector

protected abstract LeafBucketCollector getLeafCollector(org.apache.lucene.index.LeafReaderContext ctx,
                                   LeafBucketCollector sub)
                                                 throws IOException

Get a LeafBucketCollector for the given ctx, which should delegate to the given collector.

Throws:

IOException

getLeafCollector

public final LeafBucketCollector getLeafCollector(org.apache.lucene.index.LeafReaderContext ctx)
                                           throws IOException

Specified by:

getLeafCollector in interface org.apache.lucene.search.Collector

Specified by:

getLeafCollector in class BucketCollector

Throws:

IOException

doPreCollection

protected void doPreCollection()
                        throws IOException

Can be overriden by aggregator implementation to be called back when the collection phase starts.

Throws:

IOException

preCollection

public final void preCollection()
                         throws IOException

Description copied from class: BucketCollector

Pre collection callback.

Specified by:

preCollection in class BucketCollector

Throws:

IOException

getDeferringCollector

public DeferringBucketCollector getDeferringCollector()

shouldDefer

protected boolean shouldDefer(Aggregator aggregator)

This method should be overidden by subclasses that want to defer calculation of a child aggregation until a first pass is complete and a set of buckets has been pruned. Deferring collection will require the recording of all doc/bucketIds from the first pass and then the sub class should call runDeferredCollections(long...) for the selected set of buckets that survive the pruning.

Parameters:

aggregator - the child aggregator

Returns:

true if the aggregator should be deferred until a first pass at collection has completed

runDeferredCollections

protected final void runDeferredCollections(long... bucketOrds)
                                     throws IOException

Throws:

IOException

name

public String name()

Description copied from class: Aggregator

Return the name of this aggregator.

Specified by:

name in class Aggregator

Returns:

The name of the aggregation.

parent

public Aggregator parent()

Description copied from class: Aggregator

Return the parent aggregator.

Specified by:

parent in class Aggregator

Returns:

The parent aggregator of this aggregator. The addAggregation are hierarchical in the sense that some can be composed out of others (more specifically, bucket addAggregation can define other addAggregation that will be aggregated per bucket). This method returns the direct parent aggregator that contains this aggregator, or null if there is none (meaning, this aggregator is a top level one)

subAggregators

public Aggregator[] subAggregators()

subAggregator

public Aggregator subAggregator(String aggName)

Description copied from class: Aggregator

Return the sub aggregator with the provided name.

Specified by:

subAggregator in class Aggregator

context

public AggregationContext context()

Description copied from class: Aggregator

Return the AggregationContext attached with this Aggregator.

Specified by:

context in class Aggregator

Returns:

The current aggregation context.

postCollection

public final void postCollection()
                          throws IOException

Called after collection of all document is done.

Specified by:

postCollection in class BucketCollector

Throws:

IOException

close

public void close()

Called upon release of the aggregator.

doClose

protected void doClose()

Release instance-specific data.

doPostCollection

protected void doPostCollection()
                         throws IOException

Can be overriden by aggregator implementation to be called back when the collection phase ends.

Throws:

IOException

buildEmptySubAggregations

protected final InternalAggregations buildEmptySubAggregations()

toString

public String toString()

Overrides:

toString in class Object