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

Class SideEffectBarrierStep<S>

java.lang.Object
org.apache.tinkerpop.gremlin.process.traversal.step.util.AbstractStep<S,S>
org.apache.tinkerpop.gremlin.process.traversal.step.sideEffect.SideEffectBarrierStep<S>
All Implemented Interfaces:
Serializable, Cloneable, Iterator<Traverser.Admin<S>>, Step<S,S>, Barrier<TraverserSet<S>>, LocalBarrier<S>, MemoryComputing<TraverserSet<S>>
Direct Known Subclasses:
GroupCountSideEffectStep, GroupSideEffectStep, SubgraphStep, TreeSideEffectStep
public abstract class SideEffectBarrierStep<S> extends AbstractStep<S,S> implements LocalBarrier<S>
See Also:

  • Field Details

  • Constructor Details

    • SideEffectBarrierStep

      public SideEffectBarrierStep(Traversal.Admin traversal)

  • Method Details

    • sideEffect

      protected abstract void sideEffect(Traverser.Admin<S> traverser)

    • processNextStart

      protected Traverser.Admin<S> processNextStart()
      Specified by:
      processNextStart in class AbstractStep<S,S>

    • 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>

    • hasNextBarrier

      public boolean hasNextBarrier()
      Description copied from interface: Barrier
      Whether or not the step has an accessible barrier.
      Specified by:
      hasNextBarrier in interface Barrier<S>
      Returns:
      whether a barrier exists or not

    • nextBarrier

      public TraverserSet<S> nextBarrier() throws NoSuchElementException
      Description copied from interface: Barrier
      Get the next barrier within this step. Barriers from parallel steps can be the be merged to create a single step with merge barriers.
      Specified by:
      nextBarrier in interface Barrier<S>
      Returns:
      the next barrier of the step
      Throws:
      NoSuchElementException

    • addBarrier

      public void addBarrier(TraverserSet<S> barrier)
      Description copied from interface: Barrier
      Add a barrier to the step. This typically happens when multiple parallel barriers need to become one barrier at a single step.
      Specified by:
      addBarrier in interface Barrier<S>
      Parameters:
      barrier - the barrier to merge in

    • 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,S>
      Overrides:
      reset in class AbstractStep<S,S>

    • clone

      public SideEffectBarrierStep<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,S>
      Overrides:
      clone in class AbstractStep<S,S>
      Returns:
      The cloned step