X-Git-Url: https://juplo.de/gitweb/?a=blobdiff_plain;f=src%2Fmain%2Fjava%2Fde%2Fjuplo%2Fkafka%2Fwordcount%2Fcounter%2FCounterStreamProcessor.java;h=d64eb682d3433a163f7b7f0616270b01e1a313e2;hb=refs%2Ftags%2Fcounter-1.2.3;hp=b19502dbd5507a69f8a50fc9c2b496d271ffddc0;hpb=f8f9b6397ba0096bffa463e09a2db93277a3f9cf;p=demos%2Fkafka%2Fwordcount diff --git a/src/main/java/de/juplo/kafka/wordcount/counter/CounterStreamProcessor.java b/src/main/java/de/juplo/kafka/wordcount/counter/CounterStreamProcessor.java index b19502d..d64eb68 100644 --- a/src/main/java/de/juplo/kafka/wordcount/counter/CounterStreamProcessor.java +++ b/src/main/java/de/juplo/kafka/wordcount/counter/CounterStreamProcessor.java @@ -1,14 +1,15 @@ package de.juplo.kafka.wordcount.counter; -import com.fasterxml.jackson.core.JsonProcessingException; import com.fasterxml.jackson.databind.ObjectMapper; import lombok.extern.slf4j.Slf4j; +import org.apache.kafka.common.serialization.Serdes; import org.apache.kafka.streams.KafkaStreams; import org.apache.kafka.streams.KeyValue; import org.apache.kafka.streams.StreamsBuilder; +import org.apache.kafka.streams.Topology; import org.apache.kafka.streams.kstream.KStream; -import org.apache.kafka.streams.kstream.Materialized; import org.apache.kafka.streams.state.KeyValueBytesStoreSupplier; +import org.apache.kafka.streams.kstream.*; import java.util.Properties; @@ -25,30 +26,40 @@ public class CounterStreamProcessor Properties properties, KeyValueBytesStoreSupplier storeSupplier, ObjectMapper mapper) + { + Topology topology = CounterStreamProcessor.buildTopology( + inputTopic, + outputTopic, + storeSupplier, + mapper); + + streams = new KafkaStreams(topology, properties); + } + + static Topology buildTopology( + String inputTopic, + String outputTopic, + KeyValueBytesStoreSupplier storeSupplier, + ObjectMapper mapper) { StreamsBuilder builder = new StreamsBuilder(); - KStream source = builder.stream(inputTopic); + KStream source = builder.stream( + inputTopic, + Consumed.with(Serdes.String(), null)); + source - .map((username, word) -> - { - try - { - String key = mapper.writeValueAsString(Key.of(username, word)); - return new KeyValue<>(key, word); - } - catch (JsonProcessingException e) - { - throw new RuntimeException(e); - } - }) + .map((key, word) -> new KeyValue<>(word, word)) .groupByKey() .count(Materialized.as(storeSupplier)) - .mapValues(value->Long.toString(value)) .toStream() + .map((word, count) -> new KeyValue<>(word, WordCount.of(word, count))) .to(outputTopic); - streams = new KafkaStreams(builder.build(), properties); + Topology topology = builder.build(); + log.info("\n\n{}", topology.describe()); + + return topology; } public void start()