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

Class BucketOperation

java.lang.Object

org.springframework.data.mongodb.core.aggregation.BucketOperationSupport<BucketOperation,BucketOperation.BucketOperationOutputBuilder>

org.springframework.data.mongodb.core.aggregation.BucketOperation

All Implemented Interfaces:

AggregationOperation, FieldsExposingAggregationOperation

public class BucketOperation
extends BucketOperationSupport<BucketOperation,BucketOperation.BucketOperationOutputBuilder>
implements FieldsExposingAggregationOperation

Encapsulates the aggregation framework $bucket-operation.
Bucket stage is typically used with Aggregation and $facet. Categorizes incoming documents into groups, called buckets, based on a specified expression and bucket boundaries.
We recommend to use the static factory method Aggregation.bucket(String) instead of creating instances of this class directly.

Since:

1.10

Author:

Mark Paluch

See Also:

• https://docs.mongodb.org/manual/reference/aggregation/bucket/
• BucketOperationSupport

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	BucketOperation.BucketOperationOutputBuilder	BucketOperationSupport.OutputBuilder implementation for BucketOperation.
static class	BucketOperation.ExpressionBucketOperationBuilder	BucketOperationSupport.ExpressionBucketOperationBuilderSupport implementation for BucketOperation using SpEL expression based BucketOperationSupport.Output.

Nested classes/interfaces inherited from class org.springframework.data.mongodb.core.aggregation.BucketOperationSupport

BucketOperationSupport.ExpressionBucketOperationBuilderSupport<B extends BucketOperationSupport.OutputBuilder<B,T>,T extends BucketOperationSupport<T,B>>, BucketOperationSupport.OperationOutput, BucketOperationSupport.Output, BucketOperationSupport.OutputBuilder<B extends BucketOperationSupport.OutputBuilder<B,T>,T extends BucketOperationSupport<T,B>>, BucketOperationSupport.Outputs

Nested classes/interfaces inherited from interface org.springframework.data.mongodb.core.aggregation.FieldsExposingAggregationOperation

FieldsExposingAggregationOperation.InheritsFieldsAggregationOperation

Constructor Summary

Constructors

Constructor	Description
BucketOperation(AggregationExpression groupByExpression)	Creates a new BucketOperation given a group-by expression.
BucketOperation(Field groupByField)	Creates a new BucketOperation given a group-by field.

Method Summary

Modifier and Type	Method	Description
BucketOperation.BucketOperationOutputBuilder	andOutput(String fieldName)	Creates a new BucketOperationSupport given fieldName to add an output field to the resulting bucket documents.
BucketOperation.BucketOperationOutputBuilder	andOutput(AggregationExpression expression)	Creates a new BucketOperationSupport given an AggregationExpression to add an output field to the resulting bucket documents.
BucketOperation.ExpressionBucketOperationBuilder	andOutputExpression(String expression, Object... params)	Creates a new BucketOperationSupport.ExpressionBucketOperationBuilderSupport given a SpEL expression and optional params to add an output field to the resulting bucket documents.
String	getOperator()	Return the MongoDB operator that is used for this AggregationOperation.
protected BucketOperation	newBucketOperation(BucketOperationSupport.Outputs outputs)	Implementation hook to create a new bucket operation.
org.bson.Document	toDocument(AggregationOperationContext context)	Turns the AggregationOperation into a Document by using the given AggregationOperationContext.
BucketOperation	withBoundaries(Object... boundaries)	Configures boundaries and return a new BucketOperation.
BucketOperation	withDefaultBucket(Object literal)	Configures a default bucket literal and return a new BucketOperation.

Methods inherited from class org.springframework.data.mongodb.core.aggregation.BucketOperationSupport

andOutput, andOutputCount, getFields

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.springframework.data.mongodb.core.aggregation.AggregationOperation

toPipelineStages

Methods inherited from interface org.springframework.data.mongodb.core.aggregation.FieldsExposingAggregationOperation

getFields, inheritsFields

Constructor Details

BucketOperation

public BucketOperation(Field groupByField)

Creates a new BucketOperation given a group-by field.

Parameters:

groupByField - must not be null.

BucketOperation

public BucketOperation(AggregationExpression groupByExpression)

Creates a new BucketOperation given a group-by expression.

Parameters:

groupByExpression - must not be null.

Method Details

toDocument

public org.bson.Document toDocument(AggregationOperationContext context)

Description copied from interface: AggregationOperation

Turns the AggregationOperation into a Document by using the given AggregationOperationContext.

Specified by:

toDocument in interface AggregationOperation

Overrides:

toDocument in class BucketOperationSupport<BucketOperation,BucketOperation.BucketOperationOutputBuilder>

Parameters:

context - the AggregationOperationContext to operate within. Must not be null.

Returns:

the Document

getOperator

public String getOperator()

Description copied from interface: AggregationOperation

Return the MongoDB operator that is used for this AggregationOperation. Aggregation operations should implement this method to avoid document rendering.

Specified by:

getOperator in interface AggregationOperation

Returns:

the operator used for this AggregationOperation.

withDefaultBucket

public BucketOperation withDefaultBucket(Object literal)

Configures a default bucket literal and return a new BucketOperation.

Parameters:

literal - must not be null.

Returns:

new instance of BucketOperation.

withBoundaries

public BucketOperation withBoundaries(Object... boundaries)

Configures boundaries and return a new BucketOperation. Existing boundaries are preserved and the new boundaries are appended.

Parameters:

boundaries - must not be null.

Returns:

new instance of BucketOperation.

newBucketOperation

protected BucketOperation newBucketOperation(BucketOperationSupport.Outputs outputs)

Description copied from class: BucketOperationSupport

Implementation hook to create a new bucket operation.

Specified by:

newBucketOperation in class BucketOperationSupport<BucketOperation,BucketOperation.BucketOperationOutputBuilder>

Parameters:

outputs - the outputs

Returns:

the new bucket operation.

andOutputExpression

public BucketOperation.ExpressionBucketOperationBuilder andOutputExpression(String expression,
 Object... params)

Description copied from class: BucketOperationSupport

Creates a new BucketOperationSupport.ExpressionBucketOperationBuilderSupport given a SpEL expression and optional params to add an output field to the resulting bucket documents.

Specified by:

andOutputExpression in class BucketOperationSupport<BucketOperation,BucketOperation.BucketOperationOutputBuilder>

Parameters:

expression - the SpEL expression, must not be null or empty.

params - must not be null

Returns:

new instance of BucketOperationSupport.ExpressionBucketOperationBuilderSupport to create BucketOperation.

andOutput

public BucketOperation.BucketOperationOutputBuilder andOutput(AggregationExpression expression)

Description copied from class: BucketOperationSupport

Creates a new BucketOperationSupport given an AggregationExpression to add an output field to the resulting bucket documents.

Specified by:

andOutput in class BucketOperationSupport<BucketOperation,BucketOperation.BucketOperationOutputBuilder>

Parameters:

expression - the SpEL expression, must not be null or empty.

Returns:

never null.

andOutput

public BucketOperation.BucketOperationOutputBuilder andOutput(String fieldName)

Description copied from class: BucketOperationSupport

Creates a new BucketOperationSupport given fieldName to add an output field to the resulting bucket documents. BucketOperationSupport exposes accumulation operations that can be applied to fieldName.

Specified by:

andOutput in class BucketOperationSupport<BucketOperation,BucketOperation.BucketOperationOutputBuilder>

Parameters:

fieldName - must not be null or empty.

Returns:

never null.