simplifying, using correct listener

Author: masseyke

x-pack/plugin/migrate/src/main/java/org/elasticsearch/xpack/migrate/task/ReindexDataStreamPersistentTaskExecutor.java

@@ -28,6 +28,7 @@
 import org.elasticsearch.cluster.service.ClusterService;
 import org.elasticsearch.common.settings.Setting;
 import org.elasticsearch.core.Nullable;
+import org.elasticsearch.core.Strings;
 import org.elasticsearch.core.TimeValue;
 import org.elasticsearch.index.Index;
 import org.elasticsearch.persistent.AllocatedPersistentTask;
@@ -44,7 +45,6 @@
 import java.util.List;
 import java.util.Map;
 import java.util.NoSuchElementException;
-import java.util.function.BiConsumer;
 
 import static org.elasticsearch.xpack.core.deprecation.DeprecatedIndexPredicate.getReindexRequiredPredicate;
 
@@ -221,31 +221,31 @@ private void maybeProcessNextIndex(
             l -> client.execute(
                 ReindexDataStreamIndexAction.INSTANCE,
                 reindexDataStreamIndexRequest,
-                l.delegateResponse(new BiConsumer<ActionListener<ReindexDataStreamIndexAction.Response>, Exception>() {
-                    @Override
-                    public void accept(ActionListener<ReindexDataStreamIndexAction.Response> responseActionListener, Exception e) {
-                        IndexMetadata sourceIndex = clusterService.state().getMetadata().index(index.getName());
-                        if (sourceIndex == null) {
-                            /*
-                             * One possible cause of exception here is that the source index no longer exists. This can happen if ILM
-                             * performs certain actions while reindex is happening, or if a user manually deletes it. In this case we don't
-                             * want to fail the task. We treat it as a success and move on. The updateDataStreamOrCleanup method will make
-                             * an attempt at deleting the destination index if it has been created.
-                             */
-                            logger.debug(
+                l.delegateResponse((responseActionListener, e) -> {
+                    IndexMetadata sourceIndex = clusterService.state().getMetadata().index(index.getName());
+                    if (sourceIndex == null) {
+                        /*
+                         * One possible cause of exception here is that the source index no longer exists. This can happen if ILM
+                         * performs certain actions while reindex is happening, or if a user manually deletes it. In this case we don't
+                         * want to fail the task. We treat it as a success and move on. The updateDataStreamOrCleanup method will make
+                         * an attempt at deleting the destination index if it has been created.
+                         */
+                        logger.debug(
+                            () -> Strings.format(
                                 "The source index {} in the data stream {} was removed during processing",
                                 index.getName(),
                                 sourceDataStream
-                            );
-                            // We need the destination index name in the response so that updateDataStreamOrCleanup can delete it
-                            l.onResponse(
-                                new ReindexDataStreamIndexAction.Response(
-                                    ReindexDataStreamIndexTransportAction.generateDestIndexName(index.getName())
-                                )
-                            );
-                        } else {
-                            l.onFailure(e);
-                        }
+                            ),
+                            e
+                        );
+                        // We need the destination index name in the response so that updateDataStreamOrCleanup can delete it
+                        responseActionListener.onResponse(
+                            new ReindexDataStreamIndexAction.Response(
+                                ReindexDataStreamIndexTransportAction.generateDestIndexName(index.getName())
+                            )
+                        );
+                    } else {
+                        responseActionListener.onFailure(e);
                     }
                 })
             )