Kafka Streams KStream.count metodu

Giriş

Açıklaması şöyle

count is such a commonly used form of aggregation that it is offered as a first-class operation. Once you have the stream records grouped by key (KGroupedStream), you can count the number of records of a specific key by using this operation.

The aggregate way of doing things can be replaced by a single method call!

Örnek

Şöyle yaparız

StreamsBuilder builder = new StreamsBuilder();
KStream<String, String> stream = builder.stream(INPUT_TOPIC);
stream.groupByKey().count();