private PlanEnumerator()

in wayang-commons/wayang-core/src/main/java/org/apache/wayang/core/optimizer/enumeration/PlanEnumerator.java [212:275]
51 lines of code
9 McCabe index (conditional complexity)

    private PlanEnumerator(Collection<Operator> startOperators,
                           OptimizationContext optimizationContext,
                           OperatorAlternative.Alternative enumeratedAlternative,
                           Map<OperatorAlternative, OperatorAlternative.Alternative> presettledAlternatives,
                           Map<ExecutionOperator, ExecutionTask> executedTasks,
                           Map<OutputSlot<?>, Collection<Channel>> openChannels) {

        this.optimizationContext = optimizationContext;
        this.enumeratedAlternative = enumeratedAlternative;
        this.presettledAlternatives = presettledAlternatives;
        this.executedTasks = executedTasks;
        this.openChannels = openChannels;


        // Set up start Operators.
        for (Operator startOperator : startOperators) {
            this.scheduleForEnumeration(startOperator, optimizationContext);
        }

        // Configure the enumeration.
        final Configuration configuration = this.optimizationContext.getConfiguration();
        this.isEnumeratingBranchesFirst = configuration.getBooleanProperty(
                "wayang.core.optimizer.enumeration.branchesfirst", true
        );

        // Configure the concatenations.
        final String priorityFunctionName = configuration.getStringProperty(
                "wayang.core.optimizer.enumeration.concatenationprio"
        );
        ToDoubleFunction<ConcatenationActivator> concatenationPriorityFunction;
        switch (priorityFunctionName) {
            case "slots":
                concatenationPriorityFunction = ConcatenationActivator::countNumOfOpenSlots;
                break;
            case "plans":
                concatenationPriorityFunction = ConcatenationActivator::estimateNumConcatenatedPlanImplementations;
                break;
            case "plans2":
                concatenationPriorityFunction = ConcatenationActivator::estimateNumConcatenatedPlanImplementations2;
                break;
            case "random":
                // Randomly generate a priority. However, avoid re-generate priorities, because that would increase
                // of a concatenation activator being processed, the longer it is in the queue (I guess).
                concatenationPriorityFunction = activator -> {
                    if (!Double.isNaN(activator.priority)) return activator.priority;
                    return Math.random();
                };
                break;
            case "none":
                concatenationPriorityFunction = activator -> 0d;
                break;
            default:
                throw new WayangException("Unknown concatenation priority function: " + priorityFunctionName);
        }

        boolean isInvertConcatenationPriorities = configuration.getBooleanProperty(
                "wayang.core.optimizer.enumeration.invertconcatenations", false
        );
        this.concatenationPriorityFunction = isInvertConcatenationPriorities ?
                activator -> -concatenationPriorityFunction.applyAsDouble(activator) :
                concatenationPriorityFunction;


    }