import lombok.extern.slf4j.Slf4j;
import org.apache.kafka.streams.*;
-import org.apache.kafka.streams.kstream.KStream;
+import org.apache.kafka.streams.kstream.Consumed;
import org.apache.kafka.streams.kstream.Materialized;
import org.apache.kafka.streams.state.KeyValueBytesStoreSupplier;
import org.apache.kafka.streams.state.QueryableStoreTypes;
import org.apache.kafka.streams.state.ReadOnlyKeyValueStore;
+import org.springframework.kafka.support.serializer.JsonSerde;
import java.util.Properties;
{
StreamsBuilder builder = new StreamsBuilder();
- KStream<User, Word> source = builder.stream(inputTopic);
-
- source
+ builder
+ .stream(
+ inputTopic,
+ Consumed.with(
+ new JsonSerde<>(User.class),
+ new JsonSerde<>(Word.class)))
.map((key, word) -> new KeyValue<>(word, word))
.groupByKey()
- .count(Materialized.as(storeSupplier))
+ .count(
+ Materialized
+ .<Word, Long>as(storeSupplier)
+ .withKeySerde(new JsonSerde<>().copyWithType(Word.class).forKeys()))
.toStream()
.map((word, counter) -> new KeyValue<>(word, WordCounter.of(word, counter)))
.to(outputTopic);