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

Class GroupOperation

java.lang.Object

org.springframework.data.mongodb.core.aggregation.GroupOperation

All Implemented Interfaces:

AggregationOperation, FieldsExposingAggregationOperation

public class GroupOperation
extends Object
implements FieldsExposingAggregationOperation

Encapsulates the aggregation framework $group-operation.

We recommend to use the static factory method Aggregation.group(Fields) instead of creating instances of this class directly.

Since:

1.3

Author:

Sebastian Herold, Thomas Darimont, Oliver Gierke, Gustavo de Geus, Christoph Strobl, Mark Paluch, Sergey Shcherbakov

See Also:

• MongoDB Aggregation Framework: $group

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static final class	GroupOperation.GroupOperationBuilder	Builder for GroupOperations on a field.

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

FieldsExposingAggregationOperation.InheritsFieldsAggregationOperation

Constructor Summary

Constructors

Modifier	Constructor	Description
	GroupOperation(Fields fields)	Creates a new GroupOperation including the given Fields.
protected	GroupOperation(GroupOperation groupOperation)	Creates a new GroupOperation from the given GroupOperation.

Method Summary

Modifier and Type	Method	Description
GroupOperation.GroupOperationBuilder	accumulate(ScriptOperators.Accumulator accumulator)	Generates an GroupOperation.GroupOperationBuilder for an $accumulator-expression.
GroupOperation.GroupOperationBuilder	addToSet(Object value)	Generates an GroupOperation.GroupOperationBuilder for an $add_to_set-expression for the given value.
GroupOperation.GroupOperationBuilder	addToSet(String reference)	Generates an GroupOperation.GroupOperationBuilder for an $add_to_set-expression for the given field-reference.
GroupOperation	and(String fieldName, AggregationExpression expression)	Adds a computed field to the GroupOperation.
protected GroupOperation	and(org.springframework.data.mongodb.core.aggregation.GroupOperation.Operation operation)	Creates a new GroupOperation from the current one adding the given GroupOperation.Operation.
GroupOperation.GroupOperationBuilder	avg(String reference)	Generates an GroupOperation.GroupOperationBuilder for an $avg-expression for the given field-reference.
GroupOperation.GroupOperationBuilder	avg(AggregationExpression expr)	Generates an GroupOperation.GroupOperationBuilder for an $avg-expression for the given AggregationExpression.
GroupOperation.GroupOperationBuilder	count()	Generates an GroupOperation.GroupOperationBuilder for a $sum-expression.
GroupOperation.GroupOperationBuilder	first(String reference)	Generates an GroupOperation.GroupOperationBuilder for a $first-expression for the given field-reference.
GroupOperation.GroupOperationBuilder	first(AggregationExpression expr)	Generates an GroupOperation.GroupOperationBuilder for a $first-expression for the given AggregationExpression.
ExposedFields	getFields()	Returns the fields exposed by the AggregationOperation.
String	getOperator()	Return the MongoDB operator that is used for this AggregationOperation.
GroupOperation.GroupOperationBuilder	last(String reference)	Generates an GroupOperation.GroupOperationBuilder for an $last-expression for the given field-reference.
GroupOperation.GroupOperationBuilder	last(AggregationExpression expr)	Generates an GroupOperation.GroupOperationBuilder for an $last-expression for the given AggregationExpression.
GroupOperation.GroupOperationBuilder	max(String reference)	Generates an GroupOperation.GroupOperationBuilder for an $max-expression that for the given field-reference.
GroupOperation.GroupOperationBuilder	max(AggregationExpression expr)	Generates an GroupOperation.GroupOperationBuilder for an $max-expression that for the given AggregationExpression.
GroupOperation.GroupOperationBuilder	min(String reference)	Generates an GroupOperation.GroupOperationBuilder for an $min-expression that for the given field-reference.
GroupOperation.GroupOperationBuilder	min(AggregationExpression expr)	Generates an GroupOperation.GroupOperationBuilder for an $min-expression that for the given AggregationExpression.
GroupOperation.GroupOperationBuilder	push(Object value)	Generates an GroupOperation.GroupOperationBuilder for an $push-expression for the given value.
GroupOperation.GroupOperationBuilder	push(String reference)	Generates an GroupOperation.GroupOperationBuilder for an $push-expression for the given field-reference.
GroupOperation.GroupOperationBuilder	stdDevPop(String reference)	Generates an GroupOperation.GroupOperationBuilder for an $stdDevPop-expression that for the given field-reference.
GroupOperation.GroupOperationBuilder	stdDevPop(AggregationExpression expr)	Generates an GroupOperation.GroupOperationBuilder for an $stdDevPop-expression that for the given AggregationExpression.
GroupOperation.GroupOperationBuilder	stdDevSamp(String reference)	Generates an GroupOperation.GroupOperationBuilder for an $stdDevSamp-expression that for the given field-reference.
GroupOperation.GroupOperationBuilder	stdDevSamp(AggregationExpression expr)	Generates an GroupOperation.GroupOperationBuilder for an $stdDevSamp-expression that for the given AggregationExpression.
GroupOperation.GroupOperationBuilder	sum(String reference)	Generates an GroupOperation.GroupOperationBuilder for a $sum-expression for the given field-reference.
GroupOperation.GroupOperationBuilder	sum(AggregationExpression expr)	Generates an GroupOperation.GroupOperationBuilder for an $sum-expression for the given AggregationExpression.
org.bson.Document	toDocument(AggregationOperationContext context)	Turns the AggregationOperation into a Document by using the given AggregationOperationContext.

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

inheritsFields

Constructor Details

GroupOperation

public GroupOperation(Fields fields)

Creates a new GroupOperation including the given Fields.

Parameters:

fields - must not be null.

GroupOperation

protected GroupOperation(GroupOperation groupOperation)

Creates a new GroupOperation from the given GroupOperation.

Parameters:

groupOperation - must not be null.

Method Details

and

protected GroupOperation and(org.springframework.data.mongodb.core.aggregation.GroupOperation.Operation operation)

Creates a new GroupOperation from the current one adding the given GroupOperation.Operation.

Parameters:

operation - must not be null.

Returns:

count

public GroupOperation.GroupOperationBuilder count()

Generates an GroupOperation.GroupOperationBuilder for a $sum-expression.

Count expressions are emulated via $sum: 1.

Returns:

sum

public GroupOperation.GroupOperationBuilder sum(String reference)

Generates an GroupOperation.GroupOperationBuilder for a $sum-expression for the given field-reference.

Parameters:

reference -

Returns:

sum

public GroupOperation.GroupOperationBuilder sum(AggregationExpression expr)

Generates an GroupOperation.GroupOperationBuilder for an $sum-expression for the given AggregationExpression.

Parameters:

expr - must not be null.

Returns:

new instance of GroupOperation.GroupOperationBuilder. Never null.

Throws:

IllegalArgumentException - when expr is null.

Since:

1.10.8

addToSet

public GroupOperation.GroupOperationBuilder addToSet(String reference)

Generates an GroupOperation.GroupOperationBuilder for an $add_to_set-expression for the given field-reference.

Parameters:

reference -

Returns:

addToSet

public GroupOperation.GroupOperationBuilder addToSet(Object value)

Generates an GroupOperation.GroupOperationBuilder for an $add_to_set-expression for the given value.

Parameters:

value -

Returns:

last

public GroupOperation.GroupOperationBuilder last(String reference)

Generates an GroupOperation.GroupOperationBuilder for an $last-expression for the given field-reference.

Parameters:

reference -

Returns:

last

public GroupOperation.GroupOperationBuilder last(AggregationExpression expr)

Generates an GroupOperation.GroupOperationBuilder for an $last-expression for the given AggregationExpression.

Parameters:

expr -

Returns:

first

public GroupOperation.GroupOperationBuilder first(String reference)

Generates an GroupOperation.GroupOperationBuilder for a $first-expression for the given field-reference.

Parameters:

reference -

Returns:

first

public GroupOperation.GroupOperationBuilder first(AggregationExpression expr)

Generates an GroupOperation.GroupOperationBuilder for a $first-expression for the given AggregationExpression.

Parameters:

expr -

Returns:

avg

public GroupOperation.GroupOperationBuilder avg(String reference)

Generates an GroupOperation.GroupOperationBuilder for an $avg-expression for the given field-reference.

Parameters:

reference -

Returns:

avg

public GroupOperation.GroupOperationBuilder avg(AggregationExpression expr)

Generates an GroupOperation.GroupOperationBuilder for an $avg-expression for the given AggregationExpression.

Parameters:

expr -

Returns:

push

public GroupOperation.GroupOperationBuilder push(String reference)

Generates an GroupOperation.GroupOperationBuilder for an $push-expression for the given field-reference.

Parameters:

reference -

Returns:

push

public GroupOperation.GroupOperationBuilder push(Object value)

Generates an GroupOperation.GroupOperationBuilder for an $push-expression for the given value.

Parameters:

value -

Returns:

min

public GroupOperation.GroupOperationBuilder min(String reference)

Generates an GroupOperation.GroupOperationBuilder for an $min-expression that for the given field-reference.

Parameters:

reference -

Returns:

min

public GroupOperation.GroupOperationBuilder min(AggregationExpression expr)

Generates an GroupOperation.GroupOperationBuilder for an $min-expression that for the given AggregationExpression.

Parameters:

expr -

Returns:

max

public GroupOperation.GroupOperationBuilder max(String reference)

Generates an GroupOperation.GroupOperationBuilder for an $max-expression that for the given field-reference.

Parameters:

reference -

Returns:

max

public GroupOperation.GroupOperationBuilder max(AggregationExpression expr)

Generates an GroupOperation.GroupOperationBuilder for an $max-expression that for the given AggregationExpression.

Parameters:

expr -

Returns:

stdDevSamp

public GroupOperation.GroupOperationBuilder stdDevSamp(String reference)

Generates an GroupOperation.GroupOperationBuilder for an $stdDevSamp-expression that for the given field-reference.

Parameters:

reference - must not be null.

Returns:

never null.

Since:

1.10

stdDevSamp

public GroupOperation.GroupOperationBuilder stdDevSamp(AggregationExpression expr)

Generates an GroupOperation.GroupOperationBuilder for an $stdDevSamp-expression that for the given AggregationExpression.

Parameters:

expr - must not be null.

Returns:

never null.

Since:

1.10

stdDevPop

public GroupOperation.GroupOperationBuilder stdDevPop(String reference)

Generates an GroupOperation.GroupOperationBuilder for an $stdDevPop-expression that for the given field-reference.

Parameters:

reference - must not be null.

Returns:

never null.

Since:

1.10

stdDevPop

public GroupOperation.GroupOperationBuilder stdDevPop(AggregationExpression expr)

Generates an GroupOperation.GroupOperationBuilder for an $stdDevPop-expression that for the given AggregationExpression.

Parameters:

expr - must not be null.

Returns:

never null.

Since:

1.10

accumulate

public GroupOperation.GroupOperationBuilder accumulate(ScriptOperators.Accumulator accumulator)

Generates an GroupOperation.GroupOperationBuilder for an $accumulator-expression.

Parameters:

accumulator - must not be null.

Returns:

never null.

Since:

3.2

and

public GroupOperation and(String fieldName,
 AggregationExpression expression)

Adds a computed field to the GroupOperation.

Parameters:

expression - must not be null.

Returns:

never null.

Since:

4.0

getFields

public ExposedFields getFields()

Description copied from interface: FieldsExposingAggregationOperation

Returns the fields exposed by the AggregationOperation.

Specified by:

getFields in interface FieldsExposingAggregationOperation

Returns:

will never be null.

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

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.