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

Class SumGlobalStep<S extends Number>

java.lang.Object

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

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

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

All Implemented Interfaces:

Serializable, Cloneable, Iterator<Traverser.Admin<S>>, Step<S,S>, Barrier<S>, Generating<S,S>, MemoryComputing<S>

public final class SumGlobalStep<S extends Number>
extends ReducingBarrierStep<S,S>

Author:

Marko A. Rodriguez (http://markorodriguez.com)

See Also:

• Serialized Form

Nested Class Summary

Nested classes/interfaces inherited from class org.apache.tinkerpop.gremlin.process.traversal.step.util.ReducingBarrierStep

ReducingBarrierStep.NonEmittingSeed

Field Summary

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

hasProcessedOnce, NON_EMITTING_SEED, reducingBiOperator, seedSupplier

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
SumGlobalStep(Traversal.Admin traversal)

Method Summary

Modifier and Type	Method	Description
protected S	generateSeedFromStarts()	Advances the starts until a non-null value is found or simply returns null.
Set<TraverserRequirement>	getRequirements()	Provide the necessary TraverserRequirement that must be met by the traverser in order for the step to function properly.
void	processAllStarts()	Process all left traversers by do not yield the resultant output.
S	projectTraverser(Traverser.Admin<S> traverser)

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

addBarrier, clone, done, getBiOperator, getEmptyBarrier, getMemoryComputeKey, getSeedSupplier, hasNextBarrier, nextBarrier, processNextStart, reset, setReducingBiOperator, setSeedSupplier

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

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

Methods inherited from class java.lang.Object

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

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

generateFinalResult

Methods inherited from interface java.util.Iterator

forEachRemaining, remove

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

equals

Constructor Details

SumGlobalStep

public SumGlobalStep(Traversal.Admin traversal)

Method Details

generateSeedFromStarts

protected S generateSeedFromStarts()

Advances the starts until a non-null value is found or simply returns null. In this way, an all null stream will result in null.

Overrides:

generateSeedFromStarts in class ReducingBarrierStep<S extends Number,S extends Number>

processAllStarts

public void processAllStarts()

Description copied from interface: Barrier

Process all left traversers by do not yield the resultant output. This method is useful for steps like ReducingBarrierStep, where traversers can be processed "on the fly" and thus, reduce memory consumption.

Specified by:

processAllStarts in interface Barrier<S extends Number>

Overrides:

processAllStarts in class ReducingBarrierStep<S extends Number,S extends Number>

projectTraverser

public S projectTraverser(Traverser.Admin<S> traverser)

Specified by:

projectTraverser in class ReducingBarrierStep<S extends Number,S extends Number>

getRequirements

public Set<TraverserRequirement> getRequirements()

Description copied from interface: Step

Provide the necessary TraverserRequirement that must be met by the traverser in order for the step to function properly. The provided default implements returns an empty set.

Returns:

the set of requirements