Package org.apache.tinkerpop.gremlin.process.traversal.step.map

Class MergeEdgeStep<S>

java.lang.Object

org.apache.tinkerpop.gremlin.process.traversal.step.util.AbstractStep<S,E>

org.apache.tinkerpop.gremlin.process.traversal.step.map.FlatMapStep<S,E>

org.apache.tinkerpop.gremlin.process.traversal.step.map.MergeStep<S,Edge,Object>

org.apache.tinkerpop.gremlin.process.traversal.step.map.MergeEdgeStep<S>

All Implemented Interfaces:

Serializable, AutoCloseable, Cloneable, Iterator<Traverser.Admin<Edge>>, Step<S,Edge>, Configuring, Mutating<Event>, Parameterizing, TraversalOptionParent<Merge,S,Object>, TraversalParent

public class MergeEdgeStep<S>
extends MergeStep<S,Edge,Object>

Implementation for the mergeE() step covering both the start step version and the one used mid-traversal.

See Also:

Serialized Form

Field Summary

Fields inherited from class org.apache.tinkerpop.gremlin.process.traversal.step.map.MergeStep

callbackRegistry, first, isStart, mergeTraversal, onCreateTraversal, onMatchTraversal

Fields inherited from class org.apache.tinkerpop.gremlin.process.traversal.step.util.AbstractStep

id, labels, nextEnd, nextStep, previousStep, starts, traversal, traverserStepIdAndLabelsSetByChild

Constructor Summary

Constructors

Constructor	Description
MergeEdgeStep(Traversal.Admin traversal, boolean isStart)
MergeEdgeStep(Traversal.Admin traversal, boolean isStart, Map merge)
MergeEdgeStep(Traversal.Admin traversal, boolean isStart, Traversal.Admin<S,Map> mergeTraversal)

Method Summary

Modifier and Type	Method	Description
void	addChildOption(Merge token, Traversal.Admin<S,Object> traversalOption)	The child as defined by the token it takes, like Pick or Merge.
MergeEdgeStep<S>	clone()	Cloning is used to duplicate steps for the purpose of traversal optimization and OLTP replication.
protected Iterator<Edge>	flatMap(Traverser.Admin<S> traverser)
protected Set	getAllowedTokens()
Traversal.Admin<S,Object>	getInVTraversal()	Gets the traversal that will be used to provide the Map that will be used to identify the Direction.IN vertex during merge.
<S,C> List<Traversal.Admin<S,C>>	getLocalChildren()
Traversal.Admin<S,Object>	getOutVTraversal()	Gets the traversal that will be used to provide the Map that will be used to identify the Direction.OUT vertex during merge.
int	hashCode()
protected Map	onCreateMap(Traverser.Admin<S> traverser, Map unresolvedMergeMap, Map mergeMap)
void	reset()	Reset the state of the step such that it has no incoming starts.
protected Vertex	resolveVertex(Object arg)
protected void	resolveVertex(Merge token, Direction direction, Map map, Traverser.Admin<S> traverser, Traversal.Admin<S,Object> traversal)
protected Vertex	resolveVertex(Traverser.Admin<S> traverser, Traversal.Admin<S,Object> traversal)
protected Map<?,?>	resolveVertices(Map map, Traverser.Admin<S> traverser)
protected CloseableIterator<Edge>	searchEdges(Map search)	Translate the Map into search criteria.
void	setTraversal(Traversal.Admin<?,?> parentTraversal)	Set the Traversal that this step is contained within.
String	toString()
protected Vertex	tryAttachVertex(Vertex v)	Tries to attach a Vertex to its host Graph of the traversal.
static void	validateMapInput(Map map, boolean ignoreTokens)

Methods inherited from class org.apache.tinkerpop.gremlin.process.traversal.step.map.MergeStep

configure, getCallbackRegistry, getGraph, getMergeTraversal, getMutatingCallbackRegistry, getOnCreateTraversal, getOnMatchTraversal, getParameters, getRequirements, isFirst, isStart, materializeMap, processNextStart, validate, validate, validateNoOverrides

Methods inherited from class org.apache.tinkerpop.gremlin.process.traversal.step.map.FlatMapStep

closeIterator

Methods inherited from class org.apache.tinkerpop.gremlin.process.traversal.step.util.AbstractStep

addLabel, addStart, addStarts, equals, getId, getLabels, getNextStep, getPreviousStep, getStarts, getTraversal, hasNext, hasStarts, isTraverserStepIdAndLabelsSetByChild, next, prepareTraversalForNextStep, removeLabel, setId, setNextStep, setPreviousStep

Methods inherited from class java.lang.Object

finalize, getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface java.util.Iterator

forEachRemaining, remove

Methods inherited from interface org.apache.tinkerpop.gremlin.process.traversal.Step

equals

Methods inherited from interface org.apache.tinkerpop.gremlin.process.traversal.step.TraversalParent

addGlobalChild, addLocalChild, asStep, close, getGlobalChildren, getSelfAndChildRequirements, integrateChild, removeGlobalChild, removeLocalChild, replaceLocalChild

Constructor Detail

MergeEdgeStep

public MergeEdgeStep(Traversal.Admin traversal,
                     boolean isStart)

MergeEdgeStep

public MergeEdgeStep(Traversal.Admin traversal,
                     boolean isStart,
                     Map merge)

MergeEdgeStep

public MergeEdgeStep(Traversal.Admin traversal,
                     boolean isStart,
                     Traversal.Admin<S,Map> mergeTraversal)

Method Detail

validateMapInput

public static void validateMapInput(Map map,
                                    boolean ignoreTokens)

getOutVTraversal

public Traversal.Admin<S,Object> getOutVTraversal()

Gets the traversal that will be used to provide the Map that will be used to identify the Direction.OUT vertex during merge.

getInVTraversal

public Traversal.Admin<S,Object> getInVTraversal()

Gets the traversal that will be used to provide the Map that will be used to identify the Direction.IN vertex during merge.

addChildOption

public void addChildOption(Merge token,
                           Traversal.Admin<S,Object> traversalOption)

Description copied from interface: TraversalOptionParent

The child as defined by the token it takes, like Pick or Merge. This traversal may be of local or global scope depending on the step implementation that works with option().

Specified by:

addChildOption in interface TraversalOptionParent<Merge,S,Object>

Overrides:

addChildOption in class MergeStep<S,Edge,Object>

getLocalChildren

public <S,C> List<Traversal.Admin<S,C>> getLocalChildren()

Specified by:

getLocalChildren in interface TraversalParent

Overrides:

getLocalChildren in class MergeStep<S,Edge,Object>

hashCode

public int hashCode()

Overrides:

hashCode in class MergeStep<S,Edge,Object>

reset

public void reset()

Description copied from interface: Step

Reset the state of the step such that it has no incoming starts. Internal states are to be reset, but any sideEffect data structures are not to be recreated.

Specified by:

reset in interface Step<S,Edge>

Overrides:

reset in class MergeStep<S,Edge,Object>

toString

public String toString()

Overrides:

toString in class MergeStep<S,Edge,Object>

setTraversal

public void setTraversal(Traversal.Admin<?,?> parentTraversal)

Description copied from interface: Step

Set the Traversal that this step is contained within.

Specified by:

setTraversal in interface Step<S,Edge>

Overrides:

setTraversal in class MergeStep<S,Edge,Object>

Parameters:

parentTraversal - the new traversal for this step

clone

public MergeEdgeStep<S> clone()

Description copied from interface: Step

Cloning is used to duplicate steps for the purpose of traversal optimization and OLTP replication. When cloning a step, it is important that the steps, the cloned step is equivalent to the state of the step when Step.reset() is called. Moreover, the previous and next steps should be set to EmptyStep.

Specified by:

clone in interface Step<S,Edge>

Overrides:

clone in class MergeStep<S,Edge,Object>

Returns:

The cloned step

getAllowedTokens

protected Set getAllowedTokens()

Specified by:

getAllowedTokens in class MergeStep<S,Edge,Object>

searchEdges

protected CloseableIterator<Edge> searchEdges(Map search)

Translate the Map into search criteria. Default implementation is to translate the Map into a g.E() or g.V().out/inE() traversal. Graph providers will presumably optimize this traversal to use whatever indices are present and appropriate for efficiency. Callers are responsible for closing this iterator when finished.

resolveVertices

protected Map<?,?> resolveVertices(Map map,
                                         Traverser.Admin<S> traverser)

resolveVertex

protected void resolveVertex(Merge token,
                             Direction direction,
                             Map map,
                             Traverser.Admin<S> traverser,
                             Traversal.Admin<S,Object> traversal)

flatMap

protected Iterator<Edge> flatMap(Traverser.Admin<S> traverser)

Specified by:

flatMap in class MergeStep<S,Edge,Object>

onCreateMap

protected Map onCreateMap(Traverser.Admin<S> traverser,
                          Map unresolvedMergeMap,
                          Map mergeMap)

resolveVertex

protected Vertex resolveVertex(Traverser.Admin<S> traverser,
                               Traversal.Admin<S,Object> traversal)

resolveVertex

protected Vertex resolveVertex(Object arg)

tryAttachVertex

protected Vertex tryAttachVertex(Vertex v)

Tries to attach a Vertex to its host Graph of the traversal. If the Vertex cannot be found then an IllegalArgumentException is expected.