Package org.springframework.data.mongodb.core.aggregation

Class AggregationPipeline

java.lang.Object

org.springframework.data.mongodb.core.aggregation.AggregationPipeline

public class AggregationPipeline
extends Object

The AggregationPipeline holds the collection of aggregation stages.

Since:

3.0.2

Author:

Christoph Strobl, Mark Paluch

Constructor Summary

Constructors

Constructor	Description
AggregationPipeline()	Create an empty pipeline
AggregationPipeline(List<AggregationOperation> aggregationOperations)	Create a new pipeline with given stages.

Method Summary

Modifier and Type	Method	Description
AggregationPipeline	add(AggregationOperation aggregationOperation)	Append the given stage to the pipeline.
boolean	containsUnionWith()	Return whether this aggregation pipeline defines a $unionWith stage that may contribute documents from other collections.
List<AggregationOperation>	getOperations()	Get the list of aggregation stages.
boolean	isEmpty()
boolean	isOutOrMerge()
static AggregationPipeline	of(AggregationOperation... stages)

Methods inherited from class java.lang.Object

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

Constructor Details

AggregationPipeline

public AggregationPipeline()

Create an empty pipeline

AggregationPipeline

public AggregationPipeline(List<AggregationOperation> aggregationOperations)

Create a new pipeline with given stages.

Parameters:

aggregationOperations - must not be null.

Method Details

of

public static AggregationPipeline of(AggregationOperation... stages)

add

public AggregationPipeline add(AggregationOperation aggregationOperation)

Append the given stage to the pipeline.

Parameters:

aggregationOperation - must not be null.

Returns:

this.

getOperations

public List<AggregationOperation> getOperations()

Get the list of aggregation stages.

Returns:

never null.

isOutOrMerge

public boolean isOutOrMerge()

Returns:

true if the last aggregation stage is either $out or $merge.

containsUnionWith

public boolean containsUnionWith()

Return whether this aggregation pipeline defines a $unionWith stage that may contribute documents from other collections. Checking for presence of union stages is useful when attempting to determine the aggregation element type for mapping metadata computation.

Returns:

true the aggregation pipeline makes use of $unionWith.

Since:

3.1

isEmpty

public boolean isEmpty()

Returns:

true if the pipeline does not contain any stages.

Since:

3.1