operatorFactories.add(inMemoryExchange.createSinkFactory(subContext.getNextOperatorId()));
DriverFactory driverFactory = new DriverFactory(subContext.isInputDriver(), false, operatorFactories);
context.addDriverFactory(driverFactory);
}
inMemoryExchange.noMoreSinkFactories();
// the main driver is not an input... the union sources are the input for the plan
context.setInputDriver(false);
// Fow now, we assume that subplans always produce one symbol per channel. TODO: remove this assumption