private AsyncDecider createDecider()

in src/main/java/com/amazonaws/services/simpleworkflow/flow/worker/AsyncDecisionTaskHandler.java [185:240]
51 lines of code
9 McCabe index (conditional complexity)

    private AsyncDecider createDecider(HistoryHelper historyHelper) throws Exception {
        PollForDecisionTaskResponse decisionTask = historyHelper.getDecisionTask();
        WorkflowType workflowType = fromSdkType(decisionTask.workflowType());
        if (log.isDebugEnabled()) {
            log.debug("WorkflowTask received: taskId=" + decisionTask.startedEventId() + ", taskToken="
                    + decisionTask.taskToken() + ", workflowExecution=" + decisionTask.workflowExecution());
        }
        WorkflowDefinitionFactory workflowDefinitionFactory = definitionFactoryFactory.getWorkflowDefinitionFactory(workflowType);
        if (workflowDefinitionFactory == null) {
            ThreadLocalMetrics.getMetrics().recordCount(MetricName.TYPE_NOT_FOUND.getName(), 1, MetricName.getWorkflowTypeDimension(workflowType));
            log.error("Received decision task for workflow type not configured with a worker: workflowType="
                    + decisionTask.workflowType() + ", taskToken=" + decisionTask.taskToken() + ", workflowExecution="
                    + decisionTask.workflowExecution());
            Iterable<WorkflowType> typesToRegister = definitionFactoryFactory.getWorkflowTypesToRegister();
            StringBuilder types = new StringBuilder();
            types.append("[");
            for (WorkflowType t : typesToRegister) {
                if (types.length() > 1) {
                    types.append(", ");
                }
                types.append(t);
            }
            types.append("]");
            throw new IncompatibleWorkflowDefinition("Workflow type \"" + workflowType
                    + "\" is not supported by the WorkflowWorker. "
                    + "Possible cause is workflow type version change without changing task list name. "
                    + "Workflow types registered by the worker are: " + types.toString());
        }
        // Check if we need to look for a cached decider
        if (affinityHelper != null && affinityHelper.isAffinityWorker()) {
            AsyncDecider decider = affinityHelper.getDeciderForDecisionTask(decisionTask);
            if (decider != null) {
                // Save the component versions and workflow context data of the history helper in the cached decider
                historyHelper.setComponentVersions(decider.getHistoryHelper().getComponentVersions());
                historyHelper.setWorkflowContextData(decider.getHistoryHelper().getWorkflowContextData());
                // Skip the DecisionTaskStarted event this cached decider has seen
                historyHelper.getSingleDecisionEvents();
                // Update the cached decider with new history events
                decider.setHistoryHelper(historyHelper);
                ThreadLocalMetrics.getMetrics().recordCount(MetricName.VALID_DECIDER_FOUND_IN_CACHE.getName(), 1,
                    MetricName.getWorkflowTypeDimension(fromSdkType(decisionTask.workflowType())));
                return decider;
            }
            // No valid decider is found in cache, so we need to replay using the entire history
            historyHelper = affinityHelper.createHistoryHelperForDecisionTask(decisionTask);
            ThreadLocalMetrics.getMetrics().recordCount(MetricName.VALID_DECIDER_FOUND_IN_CACHE.getName(), 0,
                MetricName.getWorkflowTypeDimension(fromSdkType(decisionTask.workflowType())));
        }
        DecisionsHelper decisionsHelper = new DecisionsHelper(decisionTask, childWorkflowIdHandler, clientConfig);
        WorkflowTypeImplementationOptions workflowImplementationOptions = workflowDefinitionFactory.getWorkflowImplementationOptions();
        if (workflowImplementationOptions != null) {
            List<WorkflowTypeComponentImplementationVersion> implementationComponentVersions = workflowImplementationOptions.getImplementationComponentVersions();
            historyHelper.getComponentVersions().setWorkflowImplementationComponentVersions(implementationComponentVersions);
        }
        return new AsyncDecider(workflowDefinitionFactory, historyHelper, decisionsHelper);
    }