Package dev.morphia.aggregation.stages

Class Group

java.lang.Object

dev.morphia.aggregation.stages.Stage

dev.morphia.aggregation.stages.Group

public class Group
extends Stage

Groups input documents by the specified _id expression and for each distinct grouping, outputs a document.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	Group.GroupId	Defines a group ID

Constructor Summary

Constructors

Modifier	Constructor	Description
protected	Group()
protected	Group(Group.GroupId id)

Method Summary

Modifier and Type	Method	Description
Group	field(String name)	Adds a field to the group.
Group	field(String name, dev.morphia.aggregation.expressions.impls.Expression expression)	Adds a named field to the group with an expression giving the value.
dev.morphia.aggregation.expressions.impls.Fields<Group>	getFields()
Group.GroupId	getId()
static Group	group()	Creates a group stage with no ID definition
static Group	group(Group.GroupId id)	Creates a group stage with an ID definition
static Group.GroupId	id()	Creates an unnamed group ID
static Group.GroupId	id(dev.morphia.aggregation.expressions.impls.Expression name)	Creates a named group ID
static Group.GroupId	id(String name)	Creates a named group ID
static Group	of()	Deprecated, for removal: This API element is subject to removal in a future version. user group()
static Group	of(Group.GroupId id)	Deprecated, for removal: This API element is subject to removal in a future version. use group(GroupId)

Methods inherited from class dev.morphia.aggregation.stages.Stage

aggregation, stageName

Methods inherited from class java.lang.Object

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

Constructor Detail

Group

protected Group()

Group

protected Group(Group.GroupId id)

Method Detail

group

public static Group group(Group.GroupId id)

Creates a group stage with an ID definition

Parameters:

id - the group ID

Returns:

the new stage

Since:

2.2

group

public static Group group()

Creates a group stage with no ID definition

Returns:

the new stage

Since:

2.2

id

public static Group.GroupId id()

Creates an unnamed group ID

Returns:

the new groupID

id

public static Group.GroupId id(String name)

Creates a named group ID

Parameters:

name - the id name

Returns:

the new groupID

id

public static Group.GroupId id(dev.morphia.aggregation.expressions.impls.Expression name)

Creates a named group ID

Parameters:

name - the id name

Returns:

the new groupID

of

@Deprecated(forRemoval=true)
public static Group of(Group.GroupId id)

Deprecated, for removal: This API element is subject to removal in a future version.

use group(GroupId)

Creates a group stage with an ID definition

Parameters:

id - the group ID

Returns:

the new stage

of

@Deprecated(forRemoval=true)
public static Group of()

Deprecated, for removal: This API element is subject to removal in a future version.

user group()

Creates a group stage with no ID definition

Returns:

the new stage

field

public Group field(String name)

Adds a field to the group. This method is equivalent to calling field("name", Expression.field("name"))

Parameters:

name - the field name

Returns:

this

See Also:

field(String, Expression), Expressions.field(String)

field

public Group field(String name,
                   dev.morphia.aggregation.expressions.impls.Expression expression)

Adds a named field to the group with an expression giving the value.

Parameters:

name - the name of the field

expression - the expression giving the value

Returns:

this

getFields

@Nullable
@MorphiaInternal
public dev.morphia.aggregation.expressions.impls.Fields<Group> getFields()

Returns:

the fields

Developer note.

This is an internal item. Its function and presence are subject to change without warning. Its use is highly discouraged.

getId

@Nullable
@MorphiaInternal
public Group.GroupId getId()

Returns:

the ID

Developer note.

This is an internal item. Its function and presence are subject to change without warning. Its use is highly discouraged.