Examples with HasNextStep org.apache.tinkerpop.gremlin.process.traversal.step.map.HasNextStep used on opensource projects

Example 1 with HasNextStep

use of org.apache.tinkerpop.gremlin.process.traversal.step.map.HasNextStep in project sqlg by pietermartin.

the class SqlgChooseStepStrategy method apply.

@Override
public void apply(final Traversal.Admin<?, ?> traversal) {
    // noinspection OptionalGetWithoutIsPresent
    if (!(traversal.getGraph().get() instanceof SqlgGraph)) {
        return;
    }
    List<ChooseStep> chooseSteps = TraversalHelper.getStepsOfAssignableClass(ChooseStep.class, traversal);
    for (ChooseStep<S, E, M> chooseStep : chooseSteps) {
        Traversal.Admin<S, M> predicateTraversal = chooseStep.getLocalChildren().get(0);
        // The predicate branch step is a local traversal.
        // As such if it contains a ReducingBarrierStep the SqlgBranchStepBarrier will not work.
        List<ReducingBarrierStep> reducingBarrierSteps = TraversalHelper.getStepsOfAssignableClass(ReducingBarrierStep.class, predicateTraversal);
        if (!reducingBarrierSteps.isEmpty()) {
            continue;
        }
        if (predicateTraversal.getSteps().get(predicateTraversal.getSteps().size() - 1) instanceof HasNextStep) {
            predicateTraversal.removeStep(predicateTraversal.getSteps().get(predicateTraversal.getSteps().size() - 1));
        }
        SqlgBranchStepBarrier sqlgBranchStepBarrier = new SqlgChooseStepBarrier<>(traversal, predicateTraversal);
        for (String label : chooseStep.getLabels()) {
            sqlgBranchStepBarrier.addLabel(label);
        }
        try {
            Field traversalOptionsField = chooseStep.getClass().getSuperclass().getDeclaredField("traversalOptions");
            traversalOptionsField.setAccessible(true);
            Map<M, List<Traversal.Admin<S, E>>> traversalOptions = (Map<M, List<Traversal.Admin<S, E>>>) traversalOptionsField.get(chooseStep);
            for (Map.Entry<M, List<Traversal.Admin<S, E>>> entry : traversalOptions.entrySet()) {
                for (Traversal.Admin<S, E> admin : entry.getValue()) {
                    sqlgBranchStepBarrier.addGlobalChildOption(entry.getKey(), admin);
                }
            }
        } catch (NoSuchFieldException | IllegalAccessException e) {
            throw new RuntimeException(e);
        }
        TraversalHelper.replaceStep(chooseStep, sqlgBranchStepBarrier, chooseStep.getTraversal());
    }
}