Status

Current state: Under DiscussionDiscarded (duplicated by KIP-160)

Discussion thread:

JIRA: here

Please keep the discussion on the mailing list rather than commenting on the wiki (wiki discussions get unwieldy fast).

Motivation

As for now, KStream#print leads to a predefined output where key and value are printed with comma separation:

...

"[" + this.streamName + "]: " + mapper.apply(keyToPrint, valueToPrint)

Public Interfaces

The affected interface is KStream, which needs to be extended with another overloaded version of print:

void print(final Serde<K> keySerde,
           final Serde<V> valSerde,
           final String streamName,
           final KeyValueMapper<K, V, String> mapper);

Proposed Changes

Apart from the extension of the interface, the previous implementation of print will be call a new overloaded version thereof. In case no KeyValuemapper is set, null serves as the indicator to use the default output:

...