private boolean processDefaultLogic()

in core/src/main/java/com/alibaba/smart/framework/engine/bpmn/behavior/gateway/ParallelGatewayBehavior.java [75:124]
23 lines of code
3 McCabe index (conditional complexity)

    private boolean processDefaultLogic(ExecutionContext context, PvmActivity pvmActivity, ParallelGateway parallelGateway) {


        Map<String, PvmTransition> incomeTransitions = pvmActivity.getIncomeTransitions();

        int inComeTransitionSize = incomeTransitions.size();

        if (CommonGatewayHelper.isForkGateway(pvmActivity)) {
            //fork
            super.enter(context, pvmActivity);

            // TUNE 这里不太优雅,本来应该在execute方法中返回false的,但是execute的返回值是void,大意了. 暂时先不改了,否则很可能影响现有的用户
            // 此外,目前这个类绕过了execute和leave的执行,后面有机会在优化 (并行网关这个类很特殊,既承担了fork又承担了join职责)
            context.getExecutionInstance().setActive(false);
            fireEvent(context,pvmActivity, EventConstant.ACTIVITY_START);

            Collection<PvmTransition> values = pvmActivity.getOutcomeTransitions().values();

            CommonGatewayHelper.leaveAndConcurrentlyForkIfNeeded(context, pvmActivity,values);

        } else if (CommonGatewayHelper.isJoinGateway(pvmActivity)) {

            ProcessInstance processInstance = context.getProcessInstance();

            //这个同步很关键,避免多线程同时进入临界区,然后在下面的逻辑里去创建新的 join ei,然后和countOfTheJoinLatch 进行比较
            synchronized (processInstance){

                super.enter(context, pvmActivity);

                Collection<PvmTransition> inComingPvmTransitions = incomeTransitions.values();

                //当前内存中的，新产生的 active ExecutionInstance

                //当前持久化介质中中，已产生的 active ExecutionInstance。
                List<ExecutionInstance> activeExecutionList =  executionInstanceStorage.findActiveExecution(processInstance.getInstanceId(), super.processEngineConfiguration);


                int countOfTheJoinLatch = inComingPvmTransitions.size();


                //Merge 数据库中和内存中的EI。如果是 custom模式，则可能会存在重复记录(因为custom也是从内存中查询)，所以这里需要去重。 如果是 DataBase 模式，则不会有重复的EI.
                return super.doa(context, parallelGateway, processInstance, activeExecutionList, countOfTheJoinLatch, null);
            }

        }else{
            throw new EngineException("Unexpected behavior: "+pvmActivity);
        }

        return true;
    }