top10: 1.2.1 - The name of the state-store is an internal detail

[demos/kafka/wordcount] / src / main / java / de / juplo / kafka / wordcount / top10 / Top10StreamProcessor.java

diff --git a/src/main/java/de/juplo/kafka/wordcount/top10/Top10StreamProcessor.java b/src/main/java/de/juplo/kafka/wordcount/top10/Top10StreamProcessor.java
index d3846d8..70ead87 100644 (file)
--- a/src/main/java/de/juplo/kafka/wordcount/top10/Top10StreamProcessor.java
+++ b/src/main/java/de/juplo/kafka/wordcount/top10/Top10StreamProcessor.java
@@ -1,10 +1,11 @@
 package de.juplo.kafka.wordcount.top10;
 
 import lombok.extern.slf4j.Slf4j;
-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.*;
+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 java.util.Properties;
 
@@ -12,24 +13,29 @@ import java.util.Properties;
 @Slf4j
 public class Top10StreamProcessor
 {
+       public static final String STORE_NAME= "top10";
+
        public final KafkaStreams streams;
 
 
        public Top10StreamProcessor(
                        String inputTopic,
                        String outputTopic,
-                       Properties props)
+                       Properties props,
+                       KeyValueBytesStoreSupplier storeSupplier)
        {
                Topology topology = Top10StreamProcessor.buildTopology(
                                inputTopic,
-                               outputTopic);
+                               outputTopic,
+                               storeSupplier);
 
                streams = new KafkaStreams(topology, props);
        }
 
        static Topology buildTopology(
                        String inputTopic,
-                       String outputTopic)
+                       String outputTopic,
+                       KeyValueBytesStoreSupplier storeSupplier)
        {
                StreamsBuilder builder = new StreamsBuilder();
 
@@ -39,7 +45,8 @@ public class Top10StreamProcessor
                                .groupByKey()
                                .aggregate(
                                                () -> new Ranking(),
-                                               (user, entry, ranking) -> ranking.add(entry))
+                                               (user, entry, ranking) -> ranking.add(entry),
+                                               Materialized.as(storeSupplier))
                                .toStream()
                                .to(outputTopic);
 
@@ -49,6 +56,11 @@ public class Top10StreamProcessor
                return topology;
        }
 
+       ReadOnlyKeyValueStore<User, Ranking> getStore()
+       {
+               return streams.store(StoreQueryParameters.fromNameAndType(STORE_NAME, QueryableStoreTypes.keyValueStore()));
+       }
+
        public void start()
        {
                log.info("Starting Stream-Processor");