...
public Processor createProcessor(RouteContext routeContext) throws Exception {
        Processor childProcessor = routeContext.createProcessor(this);
        if (aggregationStrategy == null) {
            aggregationStrategy = new UseLatestAggregationStrategy();
        }
        if (threadPoolExecutor == null) {
            threadPoolExecutor = new ThreadPoolExecutor(4, 16, 0L, TimeUnit.MILLISECONDS, new LinkedBlockingQueue());
        }
        return new Splitter(getExpression().createExpression(routeContext), childProcessor, aggregationStrategy,
                isParallelProcessing(), threadPoolExecutor, streaming);
    }
...