From f0468349c45f374123bfe8d28eaff81cf684ed9f Mon Sep 17 00:00:00 2001
From: Kai Moritz <kai@juplo.de>
Date: Fri, 22 Apr 2022 17:53:41 +0200
Subject: [PATCH] Refactor: `EndlessConsumer` ist selbst ein
 `ConsumerRebalanceListener`
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* Vorbereitung für die Übernahme der Funktionalität in der springifizierten
  Version.
---
 .../java/de/juplo/kafka/EndlessConsumer.java  | 88 +++++++++----------
 1 file changed, 44 insertions(+), 44 deletions(-)

diff --git a/src/main/java/de/juplo/kafka/EndlessConsumer.java b/src/main/java/de/juplo/kafka/EndlessConsumer.java
index b173b12..8802df9 100644
--- a/src/main/java/de/juplo/kafka/EndlessConsumer.java
+++ b/src/main/java/de/juplo/kafka/EndlessConsumer.java
@@ -19,7 +19,7 @@ import java.util.concurrent.locks.ReentrantLock;
 
 @Slf4j
 @RequiredArgsConstructor
-public class EndlessConsumer<K, V> implements Runnable
+public class EndlessConsumer<K, V> implements ConsumerRebalanceListener, Runnable
 {
   private final ExecutorService executor;
   private final String id;
@@ -37,55 +37,55 @@ public class EndlessConsumer<K, V> implements Runnable
   private final Map<Integer, Long> offsets = new HashMap<>();
 
 
+  @Override
+  public void onPartitionsRevoked(Collection<TopicPartition> partitions)
+  {
+    partitions.forEach(tp ->
+    {
+      Integer partition = tp.partition();
+      Long newOffset = consumer.position(tp);
+      Long oldOffset = offsets.remove(partition);
+      log.info(
+          "{} - removing partition: {}, consumed {} records (offset {} -> {})",
+          id,
+          partition,
+          newOffset - oldOffset,
+          oldOffset,
+          newOffset);
+      Map<String, Long> removed = seen.remove(partition);
+      for (String key : removed.keySet())
+      {
+        log.info(
+            "{} - Seen {} messages for partition={}|key={}",
+            id,
+            removed.get(key),
+            partition,
+            key);
+      }
+    });
+  }
+
+  @Override
+  public void onPartitionsAssigned(Collection<TopicPartition> partitions)
+  {
+    partitions.forEach(tp ->
+    {
+      Integer partition = tp.partition();
+      Long offset = consumer.position(tp);
+      log.info("{} - adding partition: {}, offset={}", id, partition, offset);
+      offsets.put(partition, offset);
+      seen.put(partition, new HashMap<>());
+    });
+  }
+
+
   @Override
   public void run()
   {
     try
     {
       log.info("{} - Subscribing to topic {}", id, topic);
-      consumer.subscribe(Arrays.asList(topic), new ConsumerRebalanceListener()
-      {
-        @Override
-        public void onPartitionsRevoked(Collection<TopicPartition> partitions)
-        {
-          partitions.forEach(tp ->
-          {
-            Integer partition = tp.partition();
-            Long newOffset = consumer.position(tp);
-            Long oldOffset = offsets.remove(partition);
-            log.info(
-                "{} - removing partition: {}, consumed {} records (offset {} -> {})",
-                id,
-                partition,
-                newOffset - oldOffset,
-                oldOffset,
-                newOffset);
-            Map<String, Long> removed = seen.remove(partition);
-            for (String key : removed.keySet())
-            {
-              log.info(
-                  "{} - Seen {} messages for partition={}|key={}",
-                  id,
-                  removed.get(key),
-                  partition,
-                  key);
-            }
-          });
-        }
-
-        @Override
-        public void onPartitionsAssigned(Collection<TopicPartition> partitions)
-        {
-          partitions.forEach(tp ->
-          {
-            Integer partition = tp.partition();
-            Long offset = consumer.position(tp);
-            log.info("{} - adding partition: {}, offset={}", id, partition, offset);
-            offsets.put(partition, offset);
-            seen.put(partition, new HashMap<>());
-          });
-        }
-      });
+      consumer.subscribe(Arrays.asList(topic), this);
 
       while (true)
       {
-- 
2.20.1