Traverser.Admin (Apache TinkerPop 3.5.4 API)

All Superinterfaces:

org.apache.tinkerpop.gremlin.structure.util.Attachable<T>, Cloneable, Comparable<Traverser<T>>, Serializable, Traverser<T>

Enclosing interface:

Traverser<T>
```
public static interface Traverser.Admin<T>
extends Traverser<T>, org.apache.tinkerpop.gremlin.structure.util.Attachable<T>
```
The methods in System.Traverser are useful to underlying Step and Traversal implementations. They should not be accessed by the user during lambda-based manipulations.

Nested Class Summary
- Nested classes/interfaces inherited from interface org.apache.tinkerpop.gremlin.process.traversal.Traverser
  Traverser.Admin<T>
- Nested classes/interfaces inherited from interface org.apache.tinkerpop.gremlin.structure.util.Attachable
  org.apache.tinkerpop.gremlin.structure.util.Attachable.Exceptions, org.apache.tinkerpop.gremlin.structure.util.Attachable.Method

Field Summary

Fields
Modifier and Type Field and Description

static String HALT

Fields
Modifier and Type	Field and Description
`static String`	`HALT`

Method Summary

All Methods Instance Methods Abstract Methods Default Methods
Modifier and Type	Method and Description
`void`	`addLabels(Set<String> labels)`
`T`	`attach(Function<org.apache.tinkerpop.gremlin.structure.util.Attachable<T>,T> method)` Regenerate the detached traverser given its location at a particular vertex.
`Traverser.Admin<T>`	`detach()` Prepare the traverser for migration across a JVM boundary.
`void`	`dropLabels(Set<String> labels)` Drop all path information associated with specified labels.
`void`	`dropPath()` Drop the path of the traverser.
`TraversalSideEffects`	`getSideEffects()` Get the sideEffects associated with the traversal of the traverser.
`String`	`getStepId()` Get the step id of where the traverser is located.
`Set<String>`	`getTags()` Get the tags associated with the traverser.
`void`	`incrLoops()` Increment the number of times the traverser has gone through a looping section of traversal.
`void`	`initialiseLoops(String stepLabel, String loopName)` Initialise a loop by setting up the looping construct.
`default boolean`	`isHalted()` If the traverser has "no future" then it is done with its lifecycle.
`void`	`keepLabels(Set<String> labels)` Drop all path information not associated with specified labels.
`void`	`merge(Traverser.Admin<?> other)` When two traversers are have equality with each other, then they can be merged.
`void`	`resetLoops()` Set the number of times the traverser has gone through a loop back to 0.
`void`	`set(T t)` Set the current object location of the traverser.
`void`	`setBulk(long count)` Set the number of traversers represented by this traverser.
`void`	`setSideEffects(TraversalSideEffects sideEffects)` Set the sideEffects of the `Traversal`.
`void`	`setStepId(String stepId)` Set the step id of where the traverser is located.
`Traverser.Admin<T>`	`split()` Generate a sibling traverser of the current traverser with a full copy of all state within the sibling.
`<R> Traverser.Admin<R>`	`split(R r, Step<T,R> step)` Generate a child traverser of the current traverser for current as step and new object location.

Methods inherited from interface org.apache.tinkerpop.gremlin.process.traversal.Traverser
asAdmin, bulk, clone, compareTo, get, loops, loops, path, path, path, sack, sack, sideEffects, sideEffects

Methods inherited from interface org.apache.tinkerpop.gremlin.structure.util.Attachable
get

- Field Detail
  - HALT
```
static final String HALT
```
    See Also:
    
    Constant Field Values
- Method Detail
  - merge
```
void merge(Traverser.Admin<?> other)
```
    When two traversers are have equality with each other, then they can be merged. This method is used to merge the traversers into a single traverser. This is used for optimization where instead of enumerating all traversers, they can be counted.
    
    Parameters:
    
    other - the other traverser to merge into this traverser. Once merged, the other can be garbage collected.
  - split
```
<R> Traverser.Admin<R> split(R r,
                             Step<T,R> step)
```
    Generate a child traverser of the current traverser for current as step and new object location. The child has the path history, future, and loop information of the parent. The child extends that path history with the current as and provided R-object.
    
    Type Parameters:
    
    R - The current object type of the child
    
    Parameters:
    
    r - The current object of the child
    
    step - The step yielding the split
    
    Returns:
    
    The split traverser
  - split
```
Traverser.Admin<T> split()
```
    Generate a sibling traverser of the current traverser with a full copy of all state within the sibling.
    
    Returns:
    
    The split traverser
  - addLabels
```
void addLabels(Set<String> labels)
```
  - keepLabels
```
void keepLabels(Set<String> labels)
```
    Drop all path information not associated with specified labels. This is an optimization method that allows a traverser to save memory and increase the likelihood of bulking.
    
    Parameters:
    
    labels - the labels to keep path information for.
  - dropLabels
```
void dropLabels(Set<String> labels)
```
    Drop all path information associated with specified labels. This is an optimization method that allows a traverser to save memory and increase the likelihood of bulking.
    
    Parameters:
    
    labels - the labels to drop path information for.
  - dropPath
```
void dropPath()
```
    Drop the path of the traverser. This is an optimization method that allows a traverser to save memory and increase the likelihood of bulking.
  - set
```
void set(T t)
```
    Set the current object location of the traverser.
    
    Parameters:
    
    t - The current object of the traverser
  - initialiseLoops
```
void initialiseLoops(String stepLabel,
                     String loopName)
```
    Initialise a loop by setting up the looping construct. The step label is important to create a stack of loop counters when within a nested context. If the provided label is not the same as the current label on the stack, add a new loop counter. The loopName can be used to refer to the loops counter via the LoopsStep
    
    Parameters:
    
    stepLabel - the label of the step that is being set-up.
    
    loopName - the user defined name for referencing the loop counter or null if not set
  - incrLoops
```
void incrLoops()
```
    Increment the number of times the traverser has gone through a looping section of traversal.
  - resetLoops
```
void resetLoops()
```
    Set the number of times the traverser has gone through a loop back to 0. When a traverser exits a looping construct, this method should be called. In a nested loop context, the highest stack loop counter should be removed.
  - getStepId
```
String getStepId()
```
    Get the step id of where the traverser is located. This is typically used in multi-machine systems that require the movement of traversers between different traversal instances.
    
    Returns:
    
    The future step for the traverser
  - setStepId
```
void setStepId(String stepId)
```
    Set the step id of where the traverser is located. If the future is HALT, then isHalted() is true.
    
    Parameters:
    
    stepId - The future step of the traverser
  - isHalted
```
default boolean isHalted()
```
    If the traverser has "no future" then it is done with its lifecycle. This does not mean that the traverser is "dead," only that it has successfully passed through a Traversal.
    
    Returns:
    
    Whether the traverser is done executing or not
  - setBulk
```
void setBulk(long count)
```
    Set the number of traversers represented by this traverser.
    
    Parameters:
    
    count - the number of traversers
  - detach
```
Traverser.Admin<T> detach()
```
    Prepare the traverser for migration across a JVM boundary.
    
    Returns:
    
    The deflated traverser
  - attach
```
T attach(Function<org.apache.tinkerpop.gremlin.structure.util.Attachable<T>,T> method)
```
    Regenerate the detached traverser given its location at a particular vertex.
    
    Specified by:
    
    attach in interface org.apache.tinkerpop.gremlin.structure.util.Attachable<T>
    
    Parameters:
    
    method - The method by which to attach a Traverser to an vertex.
    
    Returns:
    
    The inflated traverser
  - setSideEffects
```
void setSideEffects(TraversalSideEffects sideEffects)
```
    Set the sideEffects of the Traversal. Given that traversers can move between machines, it may be important to re-set this when the traverser crosses machine boundaries.
    
    Parameters:
    
    sideEffects - the sideEffects of the traversal.
  - getSideEffects
```
TraversalSideEffects getSideEffects()
```
    Get the sideEffects associated with the traversal of the traverser.
    
    Returns:
    
    the traversal sideEffects of the traverser
  - getTags
```
Set<String> getTags()
```
    Get the tags associated with the traverser. Tags are used to categorize historic behavior of a traverser. The returned set is mutable.
    
    Returns:
    
    the set of tags associated with the traverser.

Interface Traverser.Admin<T>

Nested Class Summary

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

Nested classes/interfaces inherited from interface org.apache.tinkerpop.gremlin.structure.util.Attachable

Field Summary

Method Summary

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

Methods inherited from interface org.apache.tinkerpop.gremlin.structure.util.Attachable

Field Detail

HALT

Method Detail

merge

split

split

addLabels

keepLabels

dropLabels

dropPath

set

initialiseLoops

incrLoops

resetLoops

getStepId

setStepId

isHalted

setBulk

detach

attach

setSideEffects

getSideEffects

getTags