KAFKA-14247: add handler impl to the prototype (apache#12775)

Minor revision for KAFKA-14247. Added how the handler is called and constructed to the prototype code path.

Reviewers: John Roesler <[email protected]>, Kirk True <[email protected]>

Author: philipnee

clients/src/main/java/org/apache/kafka/clients/consumer/internals/DefaultBackgroundThread.java

@@ -64,27 +64,6 @@ public class DefaultBackgroundThread extends KafkaThread {
     private final AtomicReference<Optional<RuntimeException>> exception =
         new AtomicReference<>(Optional.empty());
 
-    public DefaultBackgroundThread(final ConsumerConfig config,
-                                   final LogContext logContext,
-                                   final BlockingQueue<ApplicationEvent> applicationEventQueue,
-                                   final BlockingQueue<BackgroundEvent> backgroundEventQueue,
-                                   final SubscriptionState subscriptions,
-                                   final ConsumerMetadata metadata,
-                                   final ConsumerNetworkClient networkClient,
-                                   final Metrics metrics) {
-        this(
-            Time.SYSTEM,
-            config,
-            logContext,
-            applicationEventQueue,
-            backgroundEventQueue,
-            subscriptions,
-            metadata,
-            networkClient,
-            metrics
-        );
-    }
-
     public DefaultBackgroundThread(final Time time,
                                    final ConsumerConfig config,
                                    final LogContext logContext,

clients/src/main/java/org/apache/kafka/clients/consumer/internals/DefaultEventHandler.java

@@ -35,6 +35,7 @@
 import java.util.List;
 import java.util.Optional;
 import java.util.concurrent.BlockingQueue;
+import java.util.concurrent.LinkedBlockingQueue;
 
 /**
  * An {@code EventHandler} that uses a single background thread to consume {@code ApplicationEvent} and produce
@@ -46,6 +47,24 @@ public class DefaultEventHandler implements EventHandler {
     private final BlockingQueue<BackgroundEvent> backgroundEventQueue;
     private final DefaultBackgroundThread backgroundThread;
 
+    public DefaultEventHandler(final ConsumerConfig config,
+                               final LogContext logContext,
+                               final SubscriptionState subscriptionState,
+                               final ApiVersions apiVersions,
+                               final Metrics metrics,
+                               final ClusterResourceListeners clusterResourceListeners,
+                               final Sensor fetcherThrottleTimeSensor) {
+        this(Time.SYSTEM,
+                config,
+                logContext,
+                new LinkedBlockingQueue<>(),
+                new LinkedBlockingQueue<>(),
+                subscriptionState,
+                apiVersions,
+                metrics,
+                clusterResourceListeners,
+                fetcherThrottleTimeSensor);
+    }
 
     public DefaultEventHandler(final Time time,
                                final ConsumerConfig config,
@@ -95,14 +114,13 @@ public DefaultEventHandler(final Time time,
             logContext
         );
         final ConsumerNetworkClient networkClient = new ConsumerNetworkClient(
-            logContext,
-            netClient,
-            metadata,
-            time,
-            config.getInt(ConsumerConfig.RETRY_BACKOFF_MS_CONFIG),
-            config.getInt(ConsumerConfig.REQUEST_TIMEOUT_MS_CONFIG),
-            config.getInt(ConsumerConfig.HEARTBEAT_INTERVAL_MS_CONFIG)
-        );
+                logContext,
+                netClient,
+                metadata,
+                time,
+                config.getLong(ConsumerConfig.RETRY_BACKOFF_MS_CONFIG),
+                config.getInt(ConsumerConfig.REQUEST_TIMEOUT_MS_CONFIG),
+                config.getInt(ConsumerConfig.HEARTBEAT_INTERVAL_MS_CONFIG));
         this.backgroundThread = new DefaultBackgroundThread(
             time,
             config,