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public class Grouped<K, V> {
 	protected final Serde<K> keySerde;
 	protected final Serde<V> valueSerde;
 	protected final String name;
	protected final Integer numPartitions; // new

	public static <K, V> Grouped<K, V> with(final String name,
    	                                    final Serde<K> keySerde,
        	                                final Serde<V> valueSerde,
											final Integer numPartitions);
}

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Proposed Changes

When configured number of partitions,  KStream application will first issue the topic lookup request and check whether the target topic is already up and running. If the target topic already exists, KStream application will log the error for topic creation failure, and still continue the initialization.

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This is a pure KStream library change that shouldn't affect previous previously setup applications. 

Rejected Alternatives

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