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/**
* {@code CogroupedKStream} is an abstraction of multiple <i>grouped</i> record streams of {@link KeyValue} pairs.
* It is an intermediate representation of one or more {@link KStream}s in order to apply one or more aggregation
* operations on the original {@link KStream} records.
* <p>
* It is an intermediate representation after a grouping of {@link KStream}s, before the aggregations are applied to
* the new partitions resulting in a {@link KTable}.
* <p>
* A {@code CogroupedKStream} must be obtained from a {@link KGroupedStream} via 
* {@link KGroupedStream#cogroup(Initializer, Aggregator, org.apache.kafka.common.serialization.Serde, String) cogroup(...)}.
*
* @param <K> Type of keys
* @param <RK> Type of key in the table, either K or Windowed&ltK&gt
* @param <V> Type of aggregate values
*/
public interface CogroupedKStream<K, V> {
    <T> CogroupedKStream<K, V> cogroup(final KGroupedStream<K, T> groupedStream,
                                       final Aggregator<? super K, ? super T, V> aggregator);

    KTable<K, V> aggregate(final Initializer<V> initializer,
                           final Serde<V> valueSerde,
                           final String storeName);
    
    KTable<K, V> aggregate(final Initializer<V> initializer,
                           final StateStoreSupplier<KeyValueStore> storeSupplier);

    KTable<Windowed<K>, V> aggregate(final Initializer<V> initializer,
                                     final Merger<? super K, V> sessionMerger,
                                     final SessionWindows sessionWindows,
                                     final Serde<V> valueSerde,
                                     final String storeName);

    KTable<Windowed<K>, V> aggregate(final Initializer<V> initializer,
                                     final Merger<? super K, V> sessionMerger,
                                     final SessionWindows sessionWindows,
                                     final StateStoreSupplier<SessionStore> storeSupplier);

    <W extends Window> KTable<Windowed<K>, V> aggregate(final Initializer<V> initializer,
                                                        final Windows<W> windows,
                                                        final Serde<V> valueSerde,
                                                        final String storeName);

    <W extends Window> KTable<Windowed<K>, V> aggregate(final Initializer<V> initializer,
                                                        final Windows<W> windows,
                                                        final StateStoreSupplier<WindowStore> storeSupplier);
}