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

Class BucketAutoOperation

java.lang.Object

org.springframework.data.mongodb.core.aggregation.BucketOperationSupport<BucketAutoOperation,BucketAutoOperation.BucketAutoOperationOutputBuilder>

org.springframework.data.mongodb.core.aggregation.BucketAutoOperation

All Implemented Interfaces:

AggregationOperation, FieldsExposingAggregationOperation

public class BucketAutoOperation
extends BucketOperationSupport<BucketAutoOperation,BucketAutoOperation.BucketAutoOperationOutputBuilder>
implements FieldsExposingAggregationOperation

Encapsulates the aggregation framework $bucketAuto-operation.
Bucket stage is typically used with Aggregation and $facet. Categorizes incoming documents into a specific number of groups, called buckets, based on a specified expression. Bucket boundaries are automatically determined in an attempt to evenly distribute the documents into the specified number of buckets.
We recommend to use the static factory method Aggregation.bucketAuto(String, int) instead of creating instances of this class directly.

Since:

1.10

Author:

Mark Paluch, Christoph Strobl

See Also:

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

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	BucketAutoOperation.BucketAutoOperationOutputBuilder	BucketOperationSupport.OutputBuilder implementation for BucketAutoOperation.
static class	BucketAutoOperation.ExpressionBucketAutoOperationBuilder	BucketOperationSupport.ExpressionBucketOperationBuilderSupport implementation for BucketAutoOperation using SpEL expression based BucketOperationSupport.Output.
static enum	BucketAutoOperation.Granularities	Supported MongoDB granularities.
static interface	BucketAutoOperation.Granularity

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
BucketAutoOperation(AggregationExpression groupByExpression, int buckets)	Creates a new BucketAutoOperation given a group-by expression.
BucketAutoOperation(Field groupByField, int buckets)	Creates a new BucketAutoOperation given a group-by field.

Method Summary

Modifier and Type	Method	Description
BucketAutoOperation.BucketAutoOperationOutputBuilder	andOutput(String fieldName)	Creates a new BucketOperationSupport given fieldName to add an output field to the resulting bucket documents.
BucketAutoOperation.BucketAutoOperationOutputBuilder	andOutput(AggregationExpression expression)	Creates a new BucketOperationSupport given an AggregationExpression to add an output field to the resulting bucket documents.
BucketAutoOperation.ExpressionBucketAutoOperationBuilder	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 BucketAutoOperation	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.
BucketAutoOperation	withBuckets(int buckets)	Configures a number of bucket buckets and return a new BucketAutoOperation.
BucketAutoOperation	withGranularity(BucketAutoOperation.Granularity granularity)	Configures granularity that specifies the preferred number series to use to ensure that the calculated boundary edges end on preferred round numbers or their powers of 10 and return a new BucketAutoOperation.

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

BucketAutoOperation

public BucketAutoOperation(Field groupByField,
 int buckets)

Creates a new BucketAutoOperation given a group-by field.

Parameters:

groupByField - must not be null.

buckets - number of buckets, must be a positive integer.

BucketAutoOperation

public BucketAutoOperation(AggregationExpression groupByExpression,
 int buckets)

Creates a new BucketAutoOperation given a group-by expression.

Parameters:

groupByExpression - must not be null.

buckets - number of buckets, must be a positive integer.

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<BucketAutoOperation,BucketAutoOperation.BucketAutoOperationOutputBuilder>

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.

withBuckets

public BucketAutoOperation withBuckets(int buckets)

Configures a number of bucket buckets and return a new BucketAutoOperation.

Parameters:

buckets - must be a positive number.

Returns:

new instance of BucketAutoOperation.

withGranularity

public BucketAutoOperation withGranularity(BucketAutoOperation.Granularity granularity)

Configures granularity that specifies the preferred number series to use to ensure that the calculated boundary edges end on preferred round numbers or their powers of 10 and return a new BucketAutoOperation.
Use either predefined BucketAutoOperation.Granularities or provide a own one.

Parameters:

granularity - must not be null.

Returns:

new instance of BucketAutoOperation.

newBucketOperation

protected BucketAutoOperation newBucketOperation(BucketOperationSupport.Outputs outputs)

Description copied from class: BucketOperationSupport

Implementation hook to create a new bucket operation.

Specified by:

newBucketOperation in class BucketOperationSupport<BucketAutoOperation,BucketAutoOperation.BucketAutoOperationOutputBuilder>

Parameters:

outputs - the outputs

Returns:

the new bucket operation.

andOutputExpression

public BucketAutoOperation.ExpressionBucketAutoOperationBuilder 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<BucketAutoOperation,BucketAutoOperation.BucketAutoOperationOutputBuilder>

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 BucketAutoOperation.BucketAutoOperationOutputBuilder 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<BucketAutoOperation,BucketAutoOperation.BucketAutoOperationOutputBuilder>

Parameters:

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

Returns:

never null.

andOutput

public BucketAutoOperation.BucketAutoOperationOutputBuilder 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<BucketAutoOperation,BucketAutoOperation.BucketAutoOperationOutputBuilder>

Parameters:

fieldName - must not be null or empty.

Returns:

never null.