Grouping (Apache TinkerPop 3.6.3 API)

All Known Implementing Classes:

GroupSideEffectStep, GroupStep
```
public interface Grouping<S,K,V>
```
An interface for common functionality of GroupStep and GroupSideEffectStep.

Method Summary

All Methods Instance Methods Abstract Methods Default Methods
Modifier and Type	Method	Description
`default Traversal.Admin<S,V>`	`convertValueTraversal(Traversal.Admin<S,V> valueTraversal)`
`default Barrier`	`determineBarrierStep(Traversal.Admin<S,V> traversal)`	Determines the first non-local `Barrier` step in the provided traversal.
`default Map<K,V>`	`doFinalReduction(Map<K,Object> map, Traversal.Admin<S,V> valueTraversal)`	When there is a `Barrier` detected by `determineBarrierStep(Traversal.Admin)` it is processed in full up to that point and then the remainder of the traversal that follows it is completed.
`Traversal.Admin<S,K>`	`getKeyTraversal()`	Determines if the provided traversal is equal to the key traversal that the `Grouping` has.
`Traversal.Admin<S,V>`	`getValueTraversal()`	Determines if the provided traversal is equal to the value traversal that the `Grouping` has.
`default boolean`	`hasBarrierInValueTraversal()`	Checks if there is a non-local `Barrier` in the value traversal.

- Method Detail
  - getKeyTraversal
```
Traversal.Admin<S,K> getKeyTraversal()
```
    Determines if the provided traversal is equal to the key traversal that the Grouping has.
  - getValueTraversal
```
Traversal.Admin<S,V> getValueTraversal()
```
    Determines if the provided traversal is equal to the value traversal that the Grouping has.
  - hasBarrierInValueTraversal
```
default boolean hasBarrierInValueTraversal()
```
    Checks if there is a non-local Barrier in the value traversal.
  - determineBarrierStep
```
default Barrier determineBarrierStep(Traversal.Admin<S,V> traversal)
```
    Determines the first non-local Barrier step in the provided traversal. This method is used by GroupStep and GroupSideEffectStep to ultimately determine the reducing bi-operator.
    
    Parameters:
    
    traversal - The traversal to inspect.
    
    Returns:
    
    The first non-local barrier step or null if no such step was found.
  - convertValueTraversal
```
default Traversal.Admin<S,V> convertValueTraversal(Traversal.Admin<S,V> valueTraversal)
```
  - doFinalReduction
```
default Map<K,V> doFinalReduction(Map<K,Object> map,
                                        Traversal.Admin<S,V> valueTraversal)
```
    When there is a Barrier detected by determineBarrierStep(Traversal.Admin) it is processed in full up to that point and then the remainder of the traversal that follows it is completed.