Package dev.morphia.query

Class Projection

java.lang.Object

dev.morphia.query.Projection

public class Projection
extends Object

Defines a query projection

Method Summary

Modifier and Type	Method	Description
FindOptions	exclude(String... fields)	Adds a field to the projection clause.
FindOptions	include(String... fields)	Adds a field to the projection clause.
FindOptions	knownFields()	Configure the project to only return known, mapped fields
Document	map(Mapper mapper, Class<?> type)	Converts this to Document form
FindOptions	project(Meta meta)	Adds a metadata field to a projection.
FindOptions	project(String field, ArraySlice slice)	Adds an sliced array field to a projection.
String	toString()

Methods inherited from class java.lang.Object

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

Method Details

exclude

public FindOptions exclude(String... fields)

Adds a field to the projection clause. The _id field is always included unless explicitly suppressed.

Parameters:

fields - the fields to exclude

Returns:

this

See Also:

• Project Fields to Return from Query

include

public FindOptions include(String... fields)

Adds a field to the projection clause. The _id field is always included unless explicitly suppressed.

Parameters:

fields - the fields to include

Returns:

this

See Also:

• Project Fields to Return from Query

knownFields

public FindOptions knownFields()

Configure the project to only return known, mapped fields

Returns:

this

map

@Nullable
public Document map(Mapper mapper,
 Class<?> type)

Converts this to Document form

Parameters:

mapper - the Mapper to use

type - the entity type

Returns:

this

project

public FindOptions project(String field,
 ArraySlice slice)

Adds an sliced array field to a projection.

Parameters:

field - the field to project

slice - the options for projecting an array field

Returns:

this

See Also:

• Project Fields to Return from Query

MongoDB documentation

$slice

project

public FindOptions project(Meta meta)

Adds a metadata field to a projection.

Parameters:

meta - the metadata option for projecting

Returns:

this

See Also:

• Project Fields to Return from Query

MongoDB documentation

$meta

toString

public String toString()

Overrides:

toString in class Object