Package org.neo4j.cypherdsl.core

Class RelationshipBase<S extends NodeBase<?>,E extends NodeBase<?>,SELF extends RelationshipBase<S,E,SELF>>

java.lang.Object

org.neo4j.cypherdsl.core.RelationshipBase<S,E,SELF>

Type Parameters:

S - The type at the start of the relationship

E - The type at the pointy end of the relationship

SELF - The type of the persistent relationship itself

All Implemented Interfaces:

ExposesProperties<Relationship>, ExposesRelationships<RelationshipChain>, Named, PatternElement, PropertyContainer, Relationship, RelationshipPattern, Visitable

@API(status=EXPERIMENTAL,
     since="2021.1.0")
public abstract class RelationshipBase<S extends NodeBase<?>,E extends NodeBase<?>,SELF extends RelationshipBase<S,E,SELF>>
extends java.lang.Object
implements Relationship

This is the base class for all relationships. It can be used with generics, specifying valid start and end nodes. This is useful when using it as a base class for a static meta model.

Since:

2021.1.0

Author:

Michael J. Simons

Nested Class Summary

Nested classes/interfaces inherited from interface org.neo4j.cypherdsl.core.Relationship

Relationship.Details, Relationship.Direction

Constructor Summary

Constructors

Modifier	Constructor	Description
protected	RelationshipBase(SymbolicName symbolicName, Node start, java.lang.String type, Properties properties, Node end)	Always creates a relationship from start to end (left to right).
protected	RelationshipBase(S start, java.lang.String type, E end)	Always creates a relationship from start to end (left to right).

Method Summary

Modifier and Type	Method	Description
void	accept(Visitor visitor)	Accept a Visitor visiting this Visitable and its nested Visitables if applicable.
Condition	asCondition()	Transform this pattern into a condition.
Relationship.Details	getDetails()	The details contains the types, properties and cardinality.
Node	getLeft()
SymbolicName	getRequiredSymbolicName()
protected java.lang.String	getRequiredType()
Node	getRight()
java.util.Optional<SymbolicName>	getSymbolicName()
Relationship	inverse()	Creates a new relationship, inverting the direction but keeping the semantics intact ((a) --> (b) becomes (b) <-- (a)).
Relationship	length(java.lang.Integer minimum, java.lang.Integer maximum)	Creates a new relationship with a new length
Relationship	max(java.lang.Integer maximum)	Creates a new relationship with a new maximum length
Relationship	min(java.lang.Integer minimum)	Creates a new relationship with a new minimum length
Operation	mutate(MapExpression properties)	Creates an Operation mutating the properties of this container to a new value.
Operation	mutate(Parameter parameter)	Creates an Operation mutating the properties of this container to a new value.
SELF	named(java.lang.String newSymbolicName)	Creates a copy of this relationship with a new symbolic name.
abstract SELF	named(SymbolicName newSymbolicName)	This method needs to be implemented to provide new, type safe instances of this relationship.
MapProjection	project(java.lang.Object... entries)	Creates a map projection based on this container.
MapProjection	project(java.util.List<java.lang.Object> entries)	Unwraps the list of entries into an array before creating a projection out of it.
Property	property(java.lang.String name)	Creates a new Property associated with this property container.
Property	property(java.lang.String... names)
Property	property(Expression lookup)	Creates a new Property associated with this property container.
RelationshipChain	relationshipBetween(Node other, java.lang.String... types)	Starts building an undirected relationship between this node and the other.
RelationshipChain	relationshipFrom(Node other, java.lang.String... types)	Starts building an incoming relationship starting at the other node.
RelationshipChain	relationshipTo(Node other, java.lang.String... types)	Starts building an outgoing relationship to the other node.
Relationship	unbounded()	Creates a new relationship with an unbound length minimum length
SELF	withProperties(java.lang.Object... keysAndValues)	Creates a a copy of this property container with additional properties.
SELF	withProperties(java.util.Map<java.lang.String,java.lang.Object> newProperties)	Creates a a copy of this property container with additional properties.
abstract SELF	withProperties(MapExpression newProperties)	This method needs to be implemented to provide new, type safe instances of this relationship.

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.neo4j.cypherdsl.core.PropertyContainer

mutate, mutate, project, project, property, property, property

Constructor Detail

RelationshipBase

protected RelationshipBase(S start,
                           java.lang.String type,
                           E end)

Always creates a relationship from start to end (left to right).

Parameters:

start - start node

end - end node

type - type of the relationship

RelationshipBase

protected RelationshipBase(SymbolicName symbolicName,
                           Node start,
                           java.lang.String type,
                           Properties properties,
                           Node end)

Always creates a relationship from start to end (left to right).

Parameters:

symbolicName - an optional symbolic name

start - start node

properties - The properties for the relationship

end - end node

type - type of the relationship

Method Detail

named

public final SELF named(java.lang.String newSymbolicName)

Description copied from interface: Relationship

Creates a copy of this relationship with a new symbolic name.

Specified by:

named in interface Relationship

Specified by:

named in interface RelationshipPattern

Parameters:

newSymbolicName - the new symbolic name.

Returns:

The new relationship.

named

public abstract SELF named(SymbolicName newSymbolicName)

This method needs to be implemented to provide new, type safe instances of this relationship.

Specified by:

named in interface Relationship

Parameters:

newSymbolicName - the new symbolic name.

Returns:

A new relationship

withProperties

public final SELF withProperties(java.lang.Object... keysAndValues)

Description copied from interface: ExposesProperties

Creates a a copy of this property container with additional properties. Creates a property container without properties when no properties are passed to this method.

Specified by:

withProperties in interface ExposesProperties<S extends NodeBase<?>>

Parameters:

keysAndValues - A list of key and values. Must be an even number, with alternating String and Expression.

Returns:

The new property container.

withProperties

public final SELF withProperties(java.util.Map<java.lang.String,java.lang.Object> newProperties)

Description copied from interface: ExposesProperties

Creates a a copy of this property container with additional properties.

Specified by:

withProperties in interface ExposesProperties<S extends NodeBase<?>>

Parameters:

newProperties - A map with the new properties

Returns:

The new property container.

withProperties

public abstract SELF withProperties(MapExpression newProperties)

This method needs to be implemented to provide new, type safe instances of this relationship.

Specified by:

withProperties in interface ExposesProperties<S extends NodeBase<?>>

Parameters:

newProperties - the new properties (can be null to remove exiting properties).

Returns:

A new relationship

getLeft

public final Node getLeft()

Specified by:

getLeft in interface Relationship

getRequiredType

protected final java.lang.String getRequiredType()

getRight

public final Node getRight()

Specified by:

getRight in interface Relationship

getDetails

public final Relationship.Details getDetails()

Description copied from interface: Relationship

The details contains the types, properties and cardinality.

Specified by:

getDetails in interface Relationship

Returns:

A wrapper around the details of this relationship.

unbounded

public final Relationship unbounded()

Description copied from interface: Relationship

Creates a new relationship with an unbound length minimum length

Specified by:

unbounded in interface Relationship

Returns:

the new relationship

min

public final Relationship min(java.lang.Integer minimum)

Description copied from interface: Relationship

Creates a new relationship with a new minimum length

Specified by:

min in interface Relationship

Parameters:

minimum - the new minimum

Returns:

the new relationship

max

public final Relationship max(java.lang.Integer maximum)

Description copied from interface: Relationship

Creates a new relationship with a new maximum length

Specified by:

max in interface Relationship

Parameters:

maximum - the new maximum

Returns:

the new relationship

length

public final Relationship length(java.lang.Integer minimum,
                                 java.lang.Integer maximum)

Description copied from interface: Relationship

Creates a new relationship with a new length

Specified by:

length in interface Relationship

Parameters:

minimum - the new minimum

maximum - the new maximum

Returns:

the new relationship

inverse

public final Relationship inverse()

Description copied from interface: Relationship

Creates a new relationship, inverting the direction but keeping the semantics intact ((a) --> (b) becomes (b) <-- (a)). A symbolic name will be removed from this relationship if any, as the it wouldn't be the same pattern to match against.

Specified by:

inverse in interface Relationship

Returns:

the new relationship

getSymbolicName

public final java.util.Optional<SymbolicName> getSymbolicName()

Specified by:

getSymbolicName in interface Named

Returns:

An optional symbolic name.

getRequiredSymbolicName

public final SymbolicName getRequiredSymbolicName()

Specified by:

getRequiredSymbolicName in interface Named

Returns:

A symbolic name

relationshipTo

public final RelationshipChain relationshipTo(Node other,
                                              java.lang.String... types)

Description copied from interface: ExposesRelationships

Starts building an outgoing relationship to the other node.

Specified by:

relationshipTo in interface ExposesRelationships<S extends NodeBase<?>>

Parameters:

other - The other end of the outgoing relationship

types - The types to match

Returns:

An ongoing relationship definition, that can be used to specify the type

relationshipFrom

public final RelationshipChain relationshipFrom(Node other,
                                                java.lang.String... types)

Description copied from interface: ExposesRelationships

Starts building an incoming relationship starting at the other node.

Specified by:

relationshipFrom in interface ExposesRelationships<S extends NodeBase<?>>

Parameters:

other - The source of the incoming relationship

types - The types to match

Returns:

An ongoing relationship definition, that can be used to specify the type

relationshipBetween

public final RelationshipChain relationshipBetween(Node other,
                                                   java.lang.String... types)

Description copied from interface: ExposesRelationships

Starts building an undirected relationship between this node and the other.

Specified by:

relationshipBetween in interface ExposesRelationships<S extends NodeBase<?>>

Parameters:

other - The other end of the relationship

types - The types to match

Returns:

An ongoing relationship definition, that can be used to specify the type

asCondition

public final Condition asCondition()

Description copied from interface: RelationshipPattern

Transform this pattern into a condition. All names of the patterns must be known upfront in the final statement, as PatternExpressions are not allowed to introduce new variables.

Specified by:

asCondition in interface RelationshipPattern

Returns:

A condition based on this pattern.

accept

public final void accept(Visitor visitor)

Description copied from interface: Visitable

Accept a Visitor visiting this Visitable and its nested Visitables if applicable.

Specified by:

accept in interface Visitable

Parameters:

visitor - the visitor to notify, must not be null.

property

public final Property property(java.lang.String name)

Description copied from interface: PropertyContainer

Creates a new Property associated with this property container. This property can be used as a lookup in other expressions. It does not add a value to the property.

Note: The property container does not track property creation and there is no possibility to enumerate all properties that have been created for this property container.

Specified by:

property in interface PropertyContainer

Parameters:

name - property name, must not be null or empty.

Returns:

a new Property associated with this named container

property

public final Property property(java.lang.String... names)

Specified by:

property in interface PropertyContainer

property

public final Property property(Expression lookup)

Description copied from interface: PropertyContainer

Creates a new Property associated with this property container. This property can be used as a lookup in other expressions. It does not add a value to the property.

The new Property object is a dynamic lookup, based on the expression passed to this method. The expression can be example another property, a function result or a Cypher parameter. A property defined in such a way will render as p[expression].

Note: The property container does not track property creation and there is no possibility to enumerate all properties that have been created for this property container.

Specified by:

property in interface PropertyContainer

Parameters:

lookup - the expression that is evaluated to lookup this property.

Returns:

a new Property associated with this named container

mutate

public final Operation mutate(Parameter parameter)

Description copied from interface: PropertyContainer

Creates an Operation mutating the properties of this container to a new value. The container does not track the operations created with this method.

Specified by:

mutate in interface PropertyContainer

Parameters:

parameter - the new properties

Returns:

A new operation.

mutate

public final Operation mutate(MapExpression properties)

Description copied from interface: PropertyContainer

Creates an Operation mutating the properties of this container to a new value. The container does not track the operations created with this method.

Specified by:

mutate in interface PropertyContainer

Parameters:

properties - the new properties

Returns:

A new operation.

project

public final MapProjection project(java.util.List<java.lang.Object> entries)

Description copied from interface: PropertyContainer

Unwraps the list of entries into an array before creating a projection out of it.

Specified by:

project in interface PropertyContainer

Parameters:

entries - A list of entries for the projection

Returns:

A map projection.

See Also:

SymbolicName.project(List)

project

public final MapProjection project(java.lang.Object... entries)

Description copied from interface: PropertyContainer

Creates a map projection based on this container. The container needs a symbolic name for this to work.

Specified by:

project in interface PropertyContainer

Parameters:

entries - A list of entries for the projection

Returns:

A map projection.

See Also:

SymbolicName.project(Object...)