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We will add a merge() method to the KStream interface.

<K,V> KStream<K,V> merge(KStream<K,V> streamsstream);

Proposed Changes

Originally, the method merge() was defined in StreamsBuilder. Through a series of calls, it called a merge() method in KStreamImpl seperate from the one we are adding. 

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In the new structure, we will add a  method override with merge():

@Override

public static <KKStream<K,V> KStream<K,V> merge(KStream<K,V> stream){

    return this.builder.merge(stream); //builder (type:InternalStreamsBuilder) was defined in the AbstractStream superclass

}

We will no longer use several variable arguments in one call, rather there will only be one stream that is taken as an input argument.

Compatibility, Deprecation, and Migration Plan

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