class StreamingRuntimeContext extends AbstractRuntimeUDFContext {

	@Override
	public <T> ReducingState<T> getReducingState(ReducingStateDescriptor<T> stateProperties) {
		KeyedStateStore keyedStateStore = checkPreconditionsAndGetKeyedStateStore(stateProperties);
		stateProperties.initializeSerializerUnlessSet(getExecutionConfig());
		return keyedStateStore.getReducingState(stateProperties);
	}

	@VisibleForTesting public  StreamingRuntimeContext(
			AbstractStreamOperator<?> operator,
			Environment env,
			Map<String, Accumulator<?, ?>> accumulators);
	public  StreamingRuntimeContext(
			Environment env,
			Map<String, Accumulator<?, ?>> accumulators,
			MetricGroup operatorMetricGroup,
			OperatorID operatorID,
			ProcessingTimeService processingTimeService,
			@Nullable KeyedStateStore keyedStateStore,
			ExternalResourceInfoProvider externalResourceInfoProvider);

}