java - How to print the frequency of a number from a kafka topic?

Question

I am using this code to print the frequency of each number coming from test_topic_3. I ran consumer to get CSV data in test_topic_3.

       KStream<String,String> inputTopic=builder.stream("test_topic_3");
        KTable<String, Long> filtered = inputTopic
                .selectKey((k, v) ->
                {
                    System.out.println("key:"+k+"|| value:"+v.split(",")[1]);
                    return v.split(",")[1];
                }
                )
                .groupByKey()
                .count();

        System.out.println("-------");
        filtered.toStream().foreach((k,v)-> System.out.println(k+"|"+v));
        System.out.println("-------");

Answer 1

等待大神答复