public static void extractAggregateFunc()

in hugegraph-core/src/main/java/org/apache/hugegraph/traversal/optimize/TraversalUtil.java [269:310]
41 lines of code
16 McCabe index (conditional complexity)

    public static void extractAggregateFunc(Step<?, ?> newStep,
                                            Traversal.Admin<?, ?> traversal) {
        PropertiesStep<?> propertiesStep = null;
        Step<?, ?> step = newStep;
        do {
            step = step.getNextStep();
            if (step instanceof PropertiesStep) {
                PropertiesStep<?> propStep = (PropertiesStep<?>) step;
                if (propStep.getReturnType() == PropertyType.VALUE &&
                    propStep.getPropertyKeys().length == 1) {
                    propertiesStep = propStep;
                }
            } else if (propertiesStep != null &&
                       step instanceof ReducingBarrierStep) {
                Aggregate.AggregateFunc aggregateFunc;
                if (step instanceof CountGlobalStep) {
                    aggregateFunc = Aggregate.AggregateFunc.COUNT;
                } else if (step instanceof MaxGlobalStep) {
                    aggregateFunc = Aggregate.AggregateFunc.MAX;
                } else if (step instanceof MinGlobalStep) {
                    aggregateFunc = Aggregate.AggregateFunc.MIN;
                } else if (step instanceof MeanGlobalStep) {
                    aggregateFunc = Aggregate.AggregateFunc.AVG;
                } else if (step instanceof SumGlobalStep) {
                    aggregateFunc = Aggregate.AggregateFunc.SUM;
                } else {
                    aggregateFunc = null;
                }

                if (aggregateFunc != null) {
                    QueryHolder holder = (QueryHolder) newStep;
                    holder.setAggregate(aggregateFunc,
                                        propertiesStep.getPropertyKeys()[0]);
                    traversal.removeStep(step);
                    traversal.removeStep(propertiesStep);
                }
            }
        } while (step instanceof FilterStep ||
                 step instanceof PropertiesStep ||
                 step instanceof IdentityStep ||
                 step instanceof NoOpBarrierStep);
    }