public Collection<StreamEvent> findEvents(StateEvent matchingEvent, IndexedEventHolder indexedEventHolder) {
        if (operator == Compare.Operator.NOT_EQUAL) {
            //for not equal trigger sequential scan
            return null;
        }
        return indexedEventHolder.findEvents(attribute, operator, valueExpressionExecutor.execute(matchingEvent));
    }
Implementation of {@link CollectionExecutor} which handle compare condition.
modules/siddhi-core/src/main/java/io/siddhi/core/util/collection/executor/CompareCollectionExecutor.java