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

Class LookupOperation

java.lang.Object

org.springframework.data.mongodb.core.aggregation.LookupOperation

All Implemented Interfaces:

AggregationOperation, FieldsExposingAggregationOperation, FieldsExposingAggregationOperation.InheritsFieldsAggregationOperation

public class LookupOperation
extends Object
implements FieldsExposingAggregationOperation, FieldsExposingAggregationOperation.InheritsFieldsAggregationOperation

Encapsulates the aggregation framework $lookup-operation. We recommend to use the builder provided via newLookup() instead of creating instances of this class directly.

Since:

1.9

Author:

Alessio Fachechi, Christoph Strobl, Mark Paluch, Sangyong Choi

See Also:

• MongoDB Aggregation Framework: $lookup

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static interface	LookupOperation.AsBuilder
static interface	LookupOperation.ForeignFieldBuilder
static interface	LookupOperation.FromBuilder
static interface	LookupOperation.LetBuilder
static interface	LookupOperation.LocalFieldBuilder
static final class	LookupOperation.LookupOperationBuilder	Builder for fluent LookupOperation creation.
static interface	LookupOperation.PipelineBuilder

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

FieldsExposingAggregationOperation.InheritsFieldsAggregationOperation

Constructor Summary

Constructors

Constructor	Description
LookupOperation(String from, Field localField, Field foreignField, VariableOperators.Let let, AggregationPipeline pipeline, Field as)	Creates a new LookupOperation for the given combination of Fields and pipeline.
LookupOperation(String from, VariableOperators.Let let, AggregationPipeline pipeline, Field as)	Creates a new LookupOperation for the given combination of Fields and pipeline.
LookupOperation(Field from, Field localField, Field foreignField, Field as)	Creates a new LookupOperation for the given Fields.

Method Summary

Modifier and Type	Method	Description
ExposedFields	getFields()	Returns the fields exposed by the AggregationOperation.
String	getOperator()	Return the MongoDB operator that is used for this AggregationOperation.
static LookupOperation.FromBuilder	newLookup()	Get a builder that allows creation of LookupOperation.
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.InheritsFieldsAggregationOperation

inheritsFields

Constructor Details

LookupOperation

public LookupOperation(Field from,
 Field localField,
 Field foreignField,
 Field as)

Creates a new LookupOperation for the given Fields.

Parameters:

from - must not be null.

localField - must not be null.

foreignField - must not be null.

as - must not be null.

LookupOperation

public LookupOperation(String from,
 @Nullable
 VariableOperators.Let let,
 AggregationPipeline pipeline,
 Field as)

Creates a new LookupOperation for the given combination of Fields and pipeline.

Parameters:

from - must not be null.

let - must not be null.

as - must not be null.

Since:

4.1

LookupOperation

public LookupOperation(String from,
 @Nullable
 Field localField,
 @Nullable
 Field foreignField,
 @Nullable
 VariableOperators.Let let,
 @Nullable
 AggregationPipeline pipeline,
 Field as)

Creates a new LookupOperation for the given combination of Fields and pipeline.

Parameters:

from - must not be null.

localField - can be null if pipeline is present.

foreignField - can be null if pipeline is present.

let - can be null if localField and foreignField are present.

as - must not be null.

Since:

4.1

Method Details

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.

newLookup

public static LookupOperation.FromBuilder newLookup()

Get a builder that allows creation of LookupOperation.

Returns:

never null.