org.elasticsearch.search.aggregations

Class Aggregator

java.lang.Object

org.elasticsearch.search.aggregations.BucketCollector

org.elasticsearch.search.aggregations.Aggregator

All Implemented Interfaces:

AutoCloseable, Releasable, ReaderContextAware

Direct Known Subclasses:

BucketsAggregator, MetricsAggregator, NonCollectingAggregator

public abstract class Aggregator
extends BucketCollector
implements Releasable

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	Aggregator.BucketAggregationMode Defines the nature of the aggregator's aggregation execution when nested in other aggregators and the buckets they create.
static interface	Aggregator.Parser Parses the aggregation request and creates the appropriate aggregator factory for it.
static class	Aggregator.SubAggCollectionMode

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

BucketCollector.BucketAnalysisCollector

Field Summary

Fields

Modifier and Type	Field and Description
protected BigArrays	bigArrays
protected Aggregator.BucketAggregationMode	bucketAggregationMode
static ParseField	COLLECT_MODE
protected BucketCollector	collectableSubAggregators
protected AggregationContext	context
protected int	depth
protected long	estimatedBucketCount
protected AggregatorFactories	factories
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	Aggregator(String name, Aggregator.BucketAggregationMode bucketAggregationMode, AggregatorFactories factories, long estimatedBucketsCount, AggregationContext context, Aggregator parent) Constructs a new Aggregator.

Method Summary

Modifier and Type	Method and Description
Aggregator.BucketAggregationMode	bucketAggregationMode()
abstract InternalAggregation	buildAggregation(long owningBucketOrdinal)
abstract InternalAggregation	buildEmptyAggregation()
protected InternalAggregations	buildEmptySubAggregations()
void	close() Called upon release of the aggregator.
AggregationContext	context()
int	depth() Return the depth of this aggregator in the aggregation tree.
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.
long	estimatedBucketCount() Return the estimated number of buckets.
void	gatherAnalysis(BucketCollector.BucketAnalysisCollector results, long bucketOrdinal) Called post-collection to gather the results from surviving buckets.
static boolean	hasParentBucketAggregator(Aggregator parent) Returns whether any of the parent aggregators has Aggregator.BucketAggregationMode.PER_BUCKET as a bucket aggregation mode.
String	name()
Aggregator	parent()
void	postCollection() Called after collection of all document is done.
protected void	preCollection()
protected void	runDeferredCollections(long... bucketOrds)
abstract boolean	shouldCollect()
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)
Aggregator[]	subAggregators()

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

collect, wrap

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.elasticsearch.common.lucene.ReaderContextAware

setNextReader

Field Detail

COLLECT_MODE

public static final ParseField COLLECT_MODE

name

protected final String name

parent

protected final Aggregator parent

context

protected final AggregationContext context

bigArrays

protected final BigArrays bigArrays

depth

protected final int depth

estimatedBucketCount

protected final long estimatedBucketCount

bucketAggregationMode

protected final Aggregator.BucketAggregationMode bucketAggregationMode

factories

protected final AggregatorFactories factories

subAggregators

protected final Aggregator[] subAggregators

collectableSubAggregators

protected BucketCollector collectableSubAggregators

Constructor Detail

Aggregator

protected Aggregator(String name,
                     Aggregator.BucketAggregationMode bucketAggregationMode,
                     AggregatorFactories factories,
                     long estimatedBucketsCount,
                     AggregationContext context,
                     Aggregator parent)

Constructs a new Aggregator.

Parameters:

name - The name of the aggregation

bucketAggregationMode - The nature of execution as a sub-aggregator (see Aggregator.BucketAggregationMode)

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

estimatedBucketsCount - When served as a sub-aggregator, indicate how many buckets the parent aggregator will generate.

context - The aggregation context

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

Method Detail

hasParentBucketAggregator

public static boolean hasParentBucketAggregator(Aggregator parent)

Returns whether any of the parent aggregators has Aggregator.BucketAggregationMode.PER_BUCKET as a bucket aggregation mode.

preCollection

protected void preCollection()

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 void runDeferredCollections(long... bucketOrds)

name

public String name()

Returns:

The name of the aggregation.

estimatedBucketCount

public final long estimatedBucketCount()

Return the estimated number of buckets.

depth

public final int depth()

Return the depth of this aggregator in the aggregation tree.

parent

public Aggregator parent()

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)

context

public AggregationContext context()

Returns:

The current aggregation context.

bucketAggregationMode

public Aggregator.BucketAggregationMode bucketAggregationMode()

Returns:

The bucket aggregation mode of this aggregator. This mode defines the nature in which the aggregation is executed

See Also:

Aggregator.BucketAggregationMode

shouldCollect

public abstract boolean shouldCollect()

Returns:

Whether this aggregator is in the state where it can collect documents. Some aggregators can do their aggregations without actually collecting documents, for example, an aggregator that computes stats over unmapped fields doesn't need to collect anything as it knows to just return "empty" stats as the aggregation result.

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.

Specified by:

close in interface AutoCloseable

Specified by:

close in interface Releasable

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

buildAggregation

public abstract InternalAggregation buildAggregation(long owningBucketOrdinal)

Returns:

The aggregated & built aggregation

gatherAnalysis

public void gatherAnalysis(BucketCollector.BucketAnalysisCollector results,
                           long bucketOrdinal)

Description copied from class: BucketCollector

Called post-collection to gather the results from surviving buckets.

Specified by:

gatherAnalysis in class BucketCollector

buildEmptyAggregation

public abstract InternalAggregation buildEmptyAggregation()

buildEmptySubAggregations

protected final InternalAggregations buildEmptySubAggregations()