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

Class CallStepPlaceholder<S,E>

java.lang.Object

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

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

All Implemented Interfaces:

Serializable, AutoCloseable, Cloneable, Iterator<Traverser.Admin<E>>, Step<S,E>, Configuring, GValueHolder<S,E>, CallStepContract<S,E>, Parameterizing, PopContaining, TraversalParent

public final class CallStepPlaceholder<S,E>
extends AbstractStep<S,E>
implements CallStepContract<S,E>, GValueHolder<S,E>

Reference implementation for service calls via the ServiceRegistry and Service APIs. This step can be used to start a traversal or it can be used mid-traversal with one at a time or barrier execution.

Author:

Mike Personick (http://github.com/mikepersonick)

See Also:

• Serialized Form

Nested Class Summary

Nested classes/interfaces inherited from interface org.apache.tinkerpop.gremlin.process.traversal.step.PopContaining

PopContaining.PopInstruction

Field Summary

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

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

Fields inherited from interface org.apache.tinkerpop.gremlin.process.traversal.step.map.CallStepContract

CONCRETE_STEPS

Constructor Summary

Constructors

Constructor	Description
CallStepPlaceholder(Traversal.Admin traversal, boolean isStart)
CallStepPlaceholder(Traversal.Admin traversal, boolean isStart, String service)
CallStepPlaceholder(Traversal.Admin traversal, boolean isStart, String service, GValue<Map<?,?>> staticParams)
CallStepPlaceholder(Traversal.Admin traversal, boolean isStart, String service, GValue<Map<?,?>> staticParams, Traversal.Admin<S,Map<?,?>> mapTraversal)

Method Summary

Modifier and Type	Method	Description
CallStep<S,E>	asConcreteStep()
CallStepPlaceholder<S,E>	clone()	Cloning is used to duplicate steps for the purpose of traversal optimization and OLTP replication.
void	configure(Object... keyValues)	Accept a configuration to the Step.
boolean	equals(Object o)
Collection<GValue<?>>	getGValues()
<S, E> List<Traversal.Admin<S,E>>	getLocalChildren()	Gets a list of all "local" child traversals for this step.
Map	getMergedParams()
protected Map	getMergedParams(Traverser.Admin<S> traverser)
Parameters	getParameters()	Gets the parameters on the step.
Set<TraverserRequirement>	getRequirements()	Provide the necessary TraverserRequirement that must be met by the traverser in order for the step to function properly.
String	getServiceName()
ServiceRegistry	getServiceRegistry()
Map	getStaticParams()
GValue<Map>	getStaticParamsAsGValue()
int	hashCode()
boolean	isParameterized()
protected Traverser.Admin<E>	processNextStart()
void	reset()	Reset the state of the step such that it has no incoming starts.
Service<S,E>	service()
Service<S,E>	serviceGValueSafe()
void	setTraversal(Traversal.Admin<?,?> parentTraversal)	Set the Traversal that this step is contained within.
String	toString()
void	updateVariable(String name, Object value)

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

addLabel, addStart, addStarts, clearLabels, 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 org.apache.tinkerpop.gremlin.process.traversal.step.GValueHolder

reduce

Methods inherited from interface java.util.Iterator

forEachRemaining, hasNext, next, remove

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

addLabel, addStart, addStarts, clearLabels, equals, getId, getLabels, getNextStep, getPreviousStep, getTraversal, hasStarts, removeLabel, setId, setNextStep, setPreviousStep

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

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

Constructor Details

CallStepPlaceholder

public CallStepPlaceholder(Traversal.Admin traversal,
 boolean isStart)

CallStepPlaceholder

public CallStepPlaceholder(Traversal.Admin traversal,
 boolean isStart,
 String service)

CallStepPlaceholder

public CallStepPlaceholder(Traversal.Admin traversal,
 boolean isStart,
 String service,
 GValue<Map<?,?>> staticParams)

CallStepPlaceholder

public CallStepPlaceholder(Traversal.Admin traversal,
 boolean isStart,
 String service,
 GValue<Map<?,?>> staticParams,
 Traversal.Admin<S,Map<?,?>> mapTraversal)

Method Details

service

public Service<S,E> service()

Specified by:

service in interface CallStepContract<S,E>

serviceGValueSafe

public Service<S,E> serviceGValueSafe()

Specified by:

serviceGValueSafe in interface CallStepContract<S,E>

getServiceName

public String getServiceName()

Specified by:

getServiceName in interface CallStepContract<S,E>

processNextStart

protected Traverser.Admin<E> processNextStart()

Specified by:

processNextStart in class AbstractStep<S,E>

getStaticParams

public Map getStaticParams()

Specified by:

getStaticParams in interface CallStepContract<S,E>

getStaticParamsAsGValue

public GValue<Map> getStaticParamsAsGValue()

Specified by:

getStaticParamsAsGValue in interface CallStepContract<S,E>

getMergedParams

public Map getMergedParams()

Specified by:

getMergedParams in interface CallStepContract<S,E>

getMergedParams

protected Map getMergedParams(Traverser.Admin<S> traverser)

getServiceRegistry

public ServiceRegistry getServiceRegistry()

Specified by:

getServiceRegistry in interface CallStepContract<S,E>

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 CallStepContract<S,E>

Specified by:

reset in interface Step<S,E>

Overrides:

reset in class AbstractStep<S,E>

getLocalChildren

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

Description copied from interface: TraversalParent

Gets a list of all "local" child traversals for this step. A "local" traversal is one which is evaluated independently for each incoming traverser to the parent step. This is typically used in cases where the child is used to process or augment each traverser individually. See LocalStep or ByModulating as examples.

Specified by:

getLocalChildren in interface TraversalParent

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,E>

Overrides:

setTraversal in class AbstractStep<S,E>

Parameters:

parentTraversal - the new traversal for this step

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.

Specified by:

getRequirements in interface Step<S,E>

Returns:

the set of requirements

toString

public String toString()

Overrides:

toString in class AbstractStep<S,E>

equals

public boolean equals(Object o)

Overrides:

equals in class AbstractStep<S,E>

hashCode

public int hashCode()

Overrides:

hashCode in class AbstractStep<S,E>

clone

public CallStepPlaceholder<S,E> 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,E>

Overrides:

clone in class AbstractStep<S,E>

Returns:

The cloned step

configure

public void configure(Object... keyValues)

Description copied from interface: Configuring

Accept a configuration to the Step. Note that this interface extends Parameterizing and so there is an expectation that the Step implementation will have a Parameters instance that will house any values passed to this method. Storing these configurations in Parameters is not a requirement however, IF the configuration is an expected option for the step and can be stored on a member field that can be accessed on the step by more direct means (i.e. like a getter method).

Specified by:

configure in interface Configuring

getParameters

public Parameters getParameters()

Description copied from interface: Parameterizing

Gets the parameters on the step.

Specified by:

getParameters in interface Parameterizing

asConcreteStep

public CallStep<S,E> asConcreteStep()

Specified by:

asConcreteStep in interface GValueHolder<S,E>

isParameterized

public boolean isParameterized()

Specified by:

isParameterized in interface GValueHolder<S,E>

updateVariable

public void updateVariable(String name,
 Object value)

Specified by:

updateVariable in interface GValueHolder<S,E>

getGValues

public Collection<GValue<?>> getGValues()

Specified by:

getGValues in interface GValueHolder<S,E>