@Override
    protected StateFactory<S> init(MetaStreamEvent metaStreamEvent, AbstractDefinition inputDefinition,
                                   ExpressionExecutor[] attributeExpressionExecutors,
                                   ConfigReader configReader, StreamEventClonerHolder streamEventClonerHolder,
                                   boolean outputExpectsExpiredEvents, boolean findToBeExecuted,
                                   SiddhiQueryContext siddhiQueryContext) {
        StateFactory<S> stateFactory = init(attributeExpressionExecutors, configReader, outputExpectsExpiredEvents,
                siddhiQueryContext);
        Attribute groupingKey = new Attribute("_hopingTimestamp", Attribute.Type.STRING);
        internalAttributes = new ArrayList<Attribute>(1);
        internalAttributes.add(groupingKey);
        metaStreamEvent.addData(groupingKey);
        return stateFactory;
    }
Performs event processing in a hopping manner

@param <S> current state of the processor
modules/siddhi-core/src/main/java/io/siddhi/core/query/processor/stream/window/HopingWindowProcessor.java